JP4481116B2 - Method for producing test liquid for measuring microorganism concentration in oral cavity - Google Patents

Description

  The present invention relates to a method for producing a test liquid for measuring microorganisms in the oral cavity.

  Microbiological testing is an important test item in medical testing, food testing, and environmental measurement.

  A wide variety of microorganisms exist in the oral cavity, and it is known that microorganisms that cause infections may exist among these microorganisms. For example, it is known that caries-related bacteria and periodontal disease-related bacteria are strongly involved in the occurrence of caries and periodontal disease. In recent years, it has been clarified that microorganisms present in the oral cavity may be involved in the development of diseases that have not been related to infectious diseases, such as heart disease, gastric ulcer, and cancer. Microbiological examinations are important not only in the dental field but also in the medical field.

  Among bacteria present in the oral cavity, bacteria belonging to mutans streptococci, bacteria belonging to the genus Lactobacillus, bacteria belonging to the genus Actinomyces are known to correlate with caries development. It is known that there is a correlation between the number of caries-related bacteria and the occurrence of caries. In particular, among the caries-related bacteria, the number of mutans streptococci has a strong correlation with the occurrence of caries. Caries is a disease in which decalcification under the surface of the enamel progresses due to acid produced and accumulated in the plaque by the caries-related bacteria, and the caries risk in the oral cavity of humans is determined by examining the number of caries-related bacteria. be able to.

  Until now, a plurality of kits for measuring caries-related bacteria concentration using a subject containing dental plaque and / or saliva have been commercially available. As a performance required for a kit for measuring caries-related bacteria concentration, it is of course possible to easily and quickly measure caries-related bacteria concentration, but it is also important that specimens are easily collected and have high reproducibility. It is.

  Stimulated saliva is most often used as a subject. This can be collected by chewing a test subject such as paraffin pellets and discharging the secreted saliva. The reason why the stimulated saliva is often used is that it is easy to collect, but it is also said that one of the reasons is that the measurement error due to the collection of the subject is small. And when measuring the caries related microbe density | concentration using stimulated saliva, it is based on the idea that the caries related microbe density | concentration in stimulated saliva reflects the caries related microbe density | concentration in dental plaque. However, caries-related bacteria in stimulated saliva, especially mutans streptococci, have been peeled off from the tooth surface, and mutans streptococci with strong cariogenic properties are firmly attached to the tooth surface and difficult to peel off. Therefore, it is better to use dental plaque as a subject to measure the bacterial concentration more accurately.

  Actually, comparing the stimulated saliva and plaque as the subject and examining the correlation between the number of mutans streptococci in the subject and the caries risk, a higher correlation was obtained in the subject containing dental plaque, The importance of using dental plaque in the determination of caries risk has been pointed out (Non-patent Document 1).

  As a method for collecting plaque, a method of wiping the tooth surface several times using a cotton swab is known. However, plaque tends to collect between teeth, but with a cotton swab it is difficult to collect plaque between teeth, and furthermore, the method of collecting plaque with such a cotton swab wipes all the tooth surfaces evenly every time. Since this is extremely difficult, there is a problem that the reproducibility of the measurement result is poor because the amount of collected plaque tends to vary. There is also a method of measuring dental caries-related bacteria in the plaque after scraping the plaque on the tooth surface using a toothpick, cotton swab, spatula, etc., and weighing the collected plaque. In the case of this method, reproducibility can be obtained by making the measurement result a value per unit plaque weight, but it has a problem that it is difficult to accurately and conveniently weigh a small amount of collected plaque. Yes.

  Recently, Fukushima reported a method for collecting plaque suspension by brushing (Non-Patent Document 2, Non-Patent Document 3). The method involves brushing the entire tooth surface with a toothbrush for about 1 minute, collecting buffer solution and collecting plaque suspension, and can collect plaque with better reproducibility than the entire tooth surface including the interdental part. In addition, the location of mutans streptococci in stimulated saliva and plaque varies from oral cavity to oral cavity, and stimulated saliva is inappropriate as a sample to evaluate individual caries risk, collected by brushing treatment It was suggested that the plaque suspension is useful for risk assessment.

  Among the above plaque collection methods, when healthy boys and adults are subjects, plaque suspension by brushing is a method that can be collected easily and with good reproducibility, but oral function is immature, or It is extremely difficult to collect dental plaque suspension with brushing treatment with high reproducibility when targeting oral subjects whose oral function is low and difficult to gargle (for example, infants, elderly people, care recipients, etc.) For this reason, the number of caries-related bacteria cannot be measured with good reproducibility. There has been a demand for a method for measuring oral microorganisms in dental plaque with good reproducibility even in subjects who have immature or decreased oral function as described above.

Takei Tsutomu, Osaka University Dental Journal, 35, 93-109, 1990 Kazuo Fukushima, Clinical Biology of Streptococcus mutans (Quisetens Publishing, supervised by Nobuhiro Hanada), 1st edition, pp. 62-82, 2003 Daisuke Iitate, Journal of Oral Hygiene, 52, 332-333, 2002

  The present invention has been made in view of the above circumstances, and when measuring oral microorganisms using a specimen containing dental plaque, fluctuations in the number of oral microorganisms in the specimen depending on the method of collecting plaque are measured. It is an object of the present invention to provide a method for producing a test liquid capable of measuring an oral microbial concentration that can be carried out accurately and with good reproducibility even in a subject whose oral cavity function is immature or reduced.

  The present inventors have intensively studied to solve the above problems. As a result, it was found that oral microorganisms can be measured accurately and with good reproducibility even using only the plaque adhered to the toothbrush used for brushing. Further studies have been made and the present invention has been completed.

That is, the present invention provides: (1) A toothbrush whose entire tooth surface is brushed is brought into contact with a liquid, and plaque and saliva adhering to the toothbrush are dispersed and / or dissolved in the liquid to obtain a test liquid. (2) The test liquid is filtered by a filtration device provided with a negative pressure means upstream of the filtrate supply chamber, in which the filtrate supply chamber and the filtrate discharge port communicate with each other through a filtration membrane. Then, the microorganisms present in the test liquid are captured on the filtration membrane, and then (3) the inside of the filtration device is made negative pressure by the negative pressure means, and the extraction solution is sucked from the filtrate outlet. Thus, the method for producing an antigen extract for measuring the concentration of oral microorganisms is characterized in that the inside of the filtration device is made to flow backward and the extract of the microorganism antigen is stored in the filtrate supply chamber .

  By the method for measuring microorganisms in the oral cavity according to the present invention, subjects whose oral function has been immature or deteriorated, for which it has been extremely difficult to obtain a sample having good reproducibility for conventional measurement (for example, infants, elderly people, nursing care required) Even in the case of subjects such as those who are subjects, it is possible to accurately measure oral microorganisms with good reproducibility. Even when healthy boys and adults are targeted, it is not necessary to include gargle after brushing, so the oral microbial concentration can be measured more easily.

  In the present invention, the test liquid is produced by bringing a toothbrush whose entire tooth surface is brushed into contact with a liquid, and dispersing and / or dissolving plaque and saliva adhering to the toothbrush in the liquid.

  In the test liquid obtained by this method, oral microorganisms contained in the plaque and saliva are present. By making the size and shape (hereinafter referred to as shape) of the toothbrush constant, the plaque and saliva adhering to the toothbrush become almost constant, and the oral cavity derived from plaque and saliva present in the test liquid The amount of the internal microorganism can be correlated with the concentration actually present in the oral cavity. Therefore, by measuring the amount of oral microorganisms in the test liquid, the concentration of microorganisms such as caries-causing bacteria in the oral cavity can be determined.

  In the present invention, oral microorganisms refer to bacteria present in the oral cavity, Rickettsiae, Chlamydia, Mycoplasma, and unicellular eukaryotes.

  In the present invention, examples of microorganisms that cause infections in the oral cavity to be measured include caries-related bacteria, periodontal disease-related bacteria, upper respiratory tract infection-causing bacteria, opportunistic infection bacteria, and the like. When specific examples are displayed for each, the caries-related bacteria include Streptococcus mutans, Streptococcus sobrinus, and other bacteria belonging to mutans streptococci, Lactobacillus, Bacteria belonging to the genus Actinomyces include porphyromonas gingivalis, actinomycetemcomitomitus Bacterium, and actinomycetem bacterium bacterium. ), Treponema denticola, Prevotella intermedia, Prevotella nigrescens, etc., and the upper respiratory tract-causing bacteria, A group of Streptococcus (Gr. (Micoplasma pneumoniae), Chlamydia pneumoniae, etc., and Candida sp., Staphylococcus aureus, and Pseudomonas (Pseudomonas) are examples of opportunistic infections.

  If the toothbrush used in the production method of the present invention can brush the entire tooth surface in the oral cavity and does not elute components that interfere with the measurement of oral microorganism concentration, the shape, material, etc. are particularly It is not limited and a known toothbrush may be used. Usually, a commercially available synthetic resin toothbrush is sufficient, but among them, a small one is preferable so that the entire tooth surface in the oral cavity can be easily brushed. The toothbrush may be washed and reused, but is preferably disposable. Furthermore, not only a manual thing but the use of an electric toothbrush is also possible.

  In the manufacturing method of the present invention, the toothbrush having a toothpaste or saliva adhered after brushing the entire tooth surface is used. Here, the total tooth surface refers to the bite surface (or cut edge), buccal side surface (or labial surface), and lingual surface of all teeth exposed in the oral cavity so that normal toothbrush hair does not reach. It does not include the surface of the interdental part. Of course, in order to measure more accurately, it is preferable to prepare a test liquid including plaque in the interdental portion. In order to obtain such interdental plaque, an interdental brush or dental floss may be used.

  The method of brushing the entire tooth surface using the toothbrush is not particularly limited, and a conventionally known brushing method can be used without any limitation. Examples of such brushing methods include a horizontal method, a vertical method, a Forzen method, a bus method, a scraping method, a Stillman method, a Charters method, and a rolling method. Among the above brushing methods, the forge method, the bath method, and the scraping method are particularly effective because they are effective in removing plaque. The brushing may be performed by the subject himself or by a third party such as a dental hygienist. When it is difficult for the subject to brush by himself (for example, an infant), it is preferable that the test is performed by a third party. In addition, a method of using a conventionally known plaque stain containing iodine or a pigment as a component for the purpose of confirming whether or not plaque has been removed on the entire tooth surface, the component contained in the plaque stain is the oral cavity of the present invention. It can be used as long as it does not affect the method for measuring microorganisms in the body. The use of a dentifrice can also be employed as long as it does not affect the method for measuring oral microorganisms of the present invention. The strength and frequency of brushing are not particularly limited as long as plaque can be sufficiently removed, but it is preferable to perform brushing for 30 seconds to 10 minutes in order to brush the entire tooth surface evenly.

Toothbrushes whose entire tooth surfaces have been brushed by the above-described method have a substantially constant amount of plaque and saliva adhering to them depending on the shape and the like. In addition, by using a toothbrush whose entire tooth surface is brushed, the plaque and saliva adhering to the toothbrush become a mixture of average plaque and saliva in the oral cavity, which depends on the difference in partial concentration. The manufacturing method of the present invention makes it possible to prepare a test liquid that can measure the oral microbial concentration with good reproducibility. Dissolved plaque and / or dissolved in the liquid. The liquid is not particularly limited as long as it does not contain a substance that interferes with the measurement when measuring the oral microorganism concentration contained in the test liquid produced by the method of the present invention. Absent. Although it depends on the method of measuring the oral microorganism concentration, in general, water-based liquids such as purified water, physiological saline, or each conventionally known buffer solution such as phosphate buffer and citrate buffer are suitable. Can be used. For such an aqueous liquid, saliva dissolves and plaque is dispersed.

  The amount of the liquid used is preferably 2 to 10 ml in order to reliably recover plaque from the toothbrush. The method of dispersing and / or dissolving the plaque adhering to the toothbrush in the liquid is not particularly limited, but it is usually carried out by immersing the flocked portion of the toothbrush completely in the liquid and swinging the toothbrush about 3 to 20 times. it can. The prepared liquid containing plaque and saliva can be used as it is, but it can be subjected to a conventionally known dispersion treatment such as sonication or mixing with glass beads or the like and stirring.

  By measuring the microbial concentration in the oral cavity in the test liquid containing plaque and saliva thus obtained, the microbial concentration in the oral cavity can be calculated.

  The method for measuring the oral microorganism concentration is not particularly limited, and examples thereof include biochemical methods, gene detection methods, culture methods, and immunological methods.

  As the biochemical method, a conventionally known biochemical test method whose biochemical activity depends on the number of microorganisms in the oral cavity can be used without any limitation. As such a biochemical test method, an ATP test can be used. Etc. are exemplified. As a gene detection method, a conventionally known gene test method such as a DNA probe method or a PCR method can be used without any limitation.

  The culture method is a method for examining the viable count of oral microorganisms in a subject, and a conventionally known culture method can be used without any limitation. There are a method of accurately quantifying the number of viable bacteria by measuring the number of colonies generated using a solid medium plate and a method of measuring semi-quantitatively after enrichment using a liquid medium. When non-selective medium is used as a culture method, it is difficult to identify oral microorganisms, so smear inspection such as Gram staining, colony morphology observation, antibiotic susceptibility test and the above various biochemical inspection methods, GC content The test and the above-described genetic test method, or the colony blot method and the above-described immunological test method are appropriately combined to identify and identify the target oral microorganism. A method of culturing by appropriately combining various selective media and various culturing methods is preferable because it facilitates identification of oral microorganisms. For example, as a method for measuring the number of mutans streptococci of caries-associated bacteria using a selective medium, a test sample is appropriately diluted, and a Mitis salivaus medium plate (also referred to as “MS medium plate”) and / or Mitis salivaus is used. An example is a method of adding to a bacitracin medium plate (also referred to as “MSB medium plate”), anaerobically culturing at 37 ° C. for 24-48 hours, and then counting the number of colonies generated. Since the number of colonies generated on the MSB medium plate is approximately equal to the number of mutans streptococci, it can be measured by multiplying the number of colonies by the dilution factor. In addition, the above various identification / identification methods can be used together to separate and identify mutans streptococcal colonies from the MS and / or MSB medium plates to accurately measure the number of viable bacteria.

  As the immunological method, conventionally known immunological methods can be used without any limitation, and as such immunological methods, aggregation methods such as latex method, radioimmunoassay method, enzyme immunoassay method, labeled antibody And various immunoblotting methods such as Western blotting and immunochromatography. (Nakajima Atsushi et al. (1988): Extraction, purification and analysis I. New basic biochemistry experiment method 2. Maruzen Co., Ltd., Nakajima Atsushi et al. (1988): Extraction, purification and analysis II. New basic biochemistry experiment Method 2. Maruzen Co., Ltd., Toshiaki Osawa et al. (1992): Molecular Immunology III. New Chemistry Experiment Course 12. Tokyo Chemical Co., Ltd.).

  A particularly preferred method as a method for measuring the concentration of oral microorganisms is that the test liquid obtained by the above-described production method is such that the filtrate supply chamber and the filtrate discharge port communicate with each other via a filtration membrane. Filtration by a filtration device equipped with a negative pressure means upstream of the supply chamber to capture microorganisms present in the test liquid on the filtration membrane, and then the negative pressure means creates a negative pressure inside the filtration device, The extraction solution is sucked from the filtrate outlet, and the inside of the filtration device is made to flow backward. The extract of the microbial antigen is stored in the filtrate supply chamber to produce the antigen extract, and then the extract in the extract is supplied. In this method, the antigen concentration is measured by an immunoassay. Hereinafter, caries-related bacteria, which are representative examples of oral microorganisms measured using the test liquid produced by the production method of the present invention, are targeted, and the caries-related substances are obtained by the above method (hereinafter abbreviated as negative pressure filtration method). A method for producing an antigen extract derived from bacteria will be described in detail.

Many caries-related bacteria are microorganisms having sugar chain antigens (serotype polysaccharide antigens), but are contained only in trace amounts of about 10 ⁴ to 10 ⁷ cells / ml in saliva and plaque. Furthermore, since it usually exists in an aggregated state covered with insoluble glucan, the method for directly analyzing the caries-associated bacteria is limited. Under such circumstances, the negative pressure filtration method can be applied as a method for extracting a sugar chain antigen when analyzing caries-related bacteria present in such saliva and plaque with high accuracy.

  The negative pressure filtration method is performed using a filtration device in which a filtrate supply chamber and a filtrate discharge port communicate with each other through a filtration membrane and a negative pressure means is provided upstream of the filtrate supply chamber. . The filtration device will be described below with reference to the drawings. FIG. 1 is a perspective view showing a typical embodiment of a filtration device used in a printing pressure filtration method and an enlarged view of a tip of a filtrate discharge port.

  The filtration device includes a filtrate supply main chamber 1 and a filtrate discharge port 2. The filtration membrane 3 is housed in a filtration membrane housing portion 4, and the filtrate supply main chamber 1 is connected to the filtration membrane housing portion 4 by a connecting portion 5. Therefore, the filtrate supply main chamber 1 and the filtrate discharge port 2 are structured to communicate with each other via the filtration membrane 3. This apparatus is a closed system with no other openings except for the filtrate discharge port 2 and a connection port to the negative pressure means provided upstream of the filtrate supply main chamber 1 described later.

  In the filtration apparatus used in the negative pressure filtration method, the filtrate supply chamber refers to all of the voids provided upstream of the filtration membrane and storing a certain amount of filtrate. Accordingly, a small space 6 is provided in the upper part of the filtration membrane 3 in the filtration membrane storage unit 4 to temporarily store the analyte liquid flowing into the filtration membrane storage unit. This constitutes a part of the filtrate supply chamber in the present invention.

  On the other hand, in the filtration device used in the negative pressure filtration method, the filtrate outlet 2 is preferably formed as a convex part such as a tube from the viewpoint of discharging the filtrate and the operability of absorbing liquid such as an extraction solution described later. .

  A negative pressure means including a syringe 9 composed of a syringe outer cylinder 7 and a plunger 8 is provided upstream of the filtrate supply main chamber 1. Any negative pressure means may be used as long as it has a function of making the inside of the apparatus have a negative pressure. However, a syringe having a pressure function like the syringe 9 enables efficient filtration by pressure filtration. It is more preferable because it can be made.

  In the method for producing an antigen extract by the negative pressure filtration method, the test liquid obtained by the above-described production method of the present invention is first supplied to the filtrate supply main chamber 1 using the filtration apparatus having the above structure. This supply operation may be appropriately performed by removing the connection portion with the syringe 9 from the filtrate supply main chamber 1 and then supplying it to the filtrate supply main chamber 1 using an instrument such as a pipette.

  Next, the analyte liquid is flowed down to the filtration membrane 3 and subjected to pressure filtration by natural filtration or by pressing the plunger 8 in the syringe 9 to pressurize the inside of the apparatus. By this filtration, the caries-related bacteria contained in the liquid are captured by the upper surface of the filtration membrane 3 and the internal pores. On the other hand, the filtrate that has passed through the filtration membrane 3 and separated from the caries-related bacteria is discharged from the filtrate outlet 2 to the outside of the apparatus. The caries-related bacteria captured on the filtration membrane 3 are washed with an appropriate washing solution (for example, pure water, buffer solution, acid solution, alkali solution, surfactant solution, etc.) as necessary. You can also. The cleaning may be performed by natural filtration or pressure filtration of the cleaning solution, or may be performed by sucking the liquid from the filtrate discharge port 2 and discharging it after flowing back through the filter device. .

  If the said filtration membrane 3 can hold | maintain oral microorganisms, such as a caries-related microbe which is a measuring object, the material, the hole diameter, a shape, etc. will not be specifically limited, A conventionally well-known filtration membrane can be used. . It is also possible to use a combination of a plurality of membranes having different pore diameters and materials so as to obtain a practically sufficient capture ability for caries-related bacteria in the test solution. In order to capture caries-related bacteria, the pore diameter is preferably 0.1 μm to 5 μm. The pore size is the pore size measured by the bubble point method (method described in JIS K3832) when the filtration membrane 3 is a porous membrane, and when the filtration membrane 3 is filter paper or the like. The retention particle diameter is measured by a method for obtaining a leakage particle size when natural filtration of barium sulfate or the like is performed (method described in JIS P 3801).

  The material of the filtration membrane 3 is glass fiber; polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polysulfone, polycarbonate, polyethylene, polypropylene, polyamide, etc. Plastics; celluloses such as cellulose, nitrocellulose, acetylcellulose, etc. can be used. Also, aggregates of glass fiber filter paper strips or activated carbon can be used.

  The shape of the filtration membrane housing 4 is not particularly limited, and may be appropriately selected according to the shape of the filtration membrane 3. The material of the filtration membrane housing 4 is not particularly limited, and plastic materials such as polypropylene and polyethylene can be used in consideration of ease of mass production and chemical resistance. For the purpose of preventing deformation or breakage of the filtration membrane 3 during liquid absorption or filtration, a plate-like structure having various pattern structures such as radial, grid, and dot on the upper or lower surface of the filtration membrane 3; nylon A net-like material such as a net; a porous material; a fiber material such as glass fiber or polypropylene nonwoven fabric may be interposed. Moreover, a filter aid such as activated carbon or filter paper powder can be added to the upper surface of the filter membrane 3 for the purpose of facilitating filtration, or a prefilter such as a glass filter or polypropylene nonwoven fabric can be installed. .

  In the negative pressure filtration method, in the syringe 9, the plunger 8 is pulled to make the inside of the filtration device have a negative pressure, and an extraction solution having an action of extracting antigens from caries-related bacteria is sucked from the filtrate outlet 2. The liquid is made to flow backward in the filtration device. As a result, the extraction solution comes into contact with the caries-related bacteria captured by the filtration membrane 3 and the antigen is extracted, and the filtration membrane 3 is accompanied by the flow of the extraction solution flowing back through the filtration device. Most of the caries-related bacteria that have been trapped in the water are again sucked into the filtrate supply main chamber 1 through the small space 6. It is possible to prevent caries-related bacteria by leaving the flow in the reverse flow or in a state where it is stored in the filtrate supply main chamber 1 for a certain time, preferably within 1 hour, more preferably 10 seconds to 20 minutes. On the other hand, the extraction solution can sufficiently act. Therefore, according to the negative pressure filtration method, the antigen extraction efficiency can be greatly improved.

  In order to further increase the extraction efficiency, after the extraction solution is stored in the filtrate main supply chamber 1, the liquid supply main chamber 1 is vibrated for a certain period of time to generate a liquid flow in the extraction solution. May be.

  As the negative pressure means, any conventionally known negative pressure means can be used as long as it is a means capable of setting the inside of the filtration apparatus to a negative pressure state with respect to the outside of the apparatus. As such negative pressure means, various manual instruments such as a syringe, a dropper, and a rubber ball, and various devices such as a vacuum pump and an aspirator can be used. Among these, a syringe, a dropper, and the like are particularly useful because they can also function as a filtrate supply chamber as in the above-described filtration device of FIG. In the case where the filtration is performed under pressure, the pressure can be appropriately performed by an independent means different from the negative pressure means. Examples of such pressurizing means include a cylinder and a pressurizing pump.

  Further, by providing a small space 6 having an appropriate volume over the entire effective filtration surface of the filtration membrane 3, the entire filtration membrane 3 can be used effectively, so that the filtration efficiency of the liquid to be filtered is improved, or Since the washing solution and / or the extraction solution can be effectively applied to the entire surface of the filtration membrane 3, the washing efficiency and the extraction efficiency may be improved, which is preferable.

  In the case of extracting a sugar chain antigen of a caries-associated bacterium, it is preferable to use an extraction solution used in a so-called nitrite extraction method. The nitrite extraction method can extract highly specific sugar chain antigens such as serotype polysaccharide antigens from microorganisms in a short time and with high efficiency (Takei Tsutomu. Osaka University Medical Journal. 35: 93-109, 1990.). . However, in the method of adding and flowing down the nitrous acid solution on the filtration membrane capturing microorganisms, it is difficult to permeate the nitrous acid solution into the details of the filtration membrane, so that sufficient extraction efficiency may not be achieved, It is particularly suitable for applying negative pressure filtration.

  In the case of carrying out the above nitrous acid extraction method, a nitrous acid solution to be an extraction solution can be generally prepared by appropriately mixing a nitrite solution and an acid solution. As the nitrite solution, an aqueous solution such as sodium nitrite or potassium nitrite can be used, and as the acid solution, an organic acid aqueous solution such as acetic acid, propionic acid or citric acid, or an inorganic acid aqueous solution such as nitric acid or hydrochloric acid can be used. At the time of mixing the nitrite solution and the acid solution, the concentration of nitrite is 0.1 to 8M, and the concentration of acid is preferably 0.1 to 16M.

  The liquid temperature of the nitrous acid solution is usually preferably 10 to 60 ° C. Further, it is preferable that the time during which the nitrous acid solution and the caries-related bacteria are in contact with each other throughout the extraction operation is at least 0.5 minutes, preferably 0.5 to 10 minutes.

  In the negative pressure filtration method, the antigen extract stored in the filtrate supply main chamber 1 and sufficiently extracted with the antigen may be collected from the filtrate supply main chamber 1 and used as an analysis sample. good. In this sampling operation, the connecting portion 5 is removed from the filtration membrane housing portion 4 to discharge the extract, or the connecting portion with the syringe 9 is removed from the filtrate supply main chamber 1 and then a pipette or the like is used. What is necessary is just to carry out suitably by extract | collecting.

  In a method in which the extraction solution is passed through the filter membrane by a single suction operation from only one direction, these liquids contain contaminants such as sticky substances in addition to caries-related bacteria. However, the extraction solution may not sufficiently act on the caries-related bacteria clogged in the pores inside the filtration membrane 3. Accordingly, in such a case, the antigen extract stored in the filtrate supply main chamber 1 and the small space 6 is subjected to natural filtration or pressure filtration immediately after storage or after holding for a certain period of time. It is preferable to use the extract discharged from the filtrate outlet 2 as an analysis sample by applying a liquid flow from the direction. In addition, if the extract discharged from the filtrate outlet 2 is used as an analysis sample in this way, residues and contaminants of these retained substances after the antigen is extracted are removed by filtration. It is meaningful when there is a possibility of adversely affecting the antigen-antibody reaction at the time.

  Further, if the above operation does not allow satisfactory extraction, the extract discharged from the filtrate discharge port 2 is again sucked from the filtrate discharge port, and the inside of the filtration device is made to flow backward. The filtrate may be stored in the filtrate supply chamber 1, and in the negative pressure filtration method, the extraction and suction operations of the extract are required as many times as required until the desired extraction efficiency is achieved, usually 1 to 10 times. What is necessary is just to repeat a liquid 0-10 times.

  Furthermore, as another method, the extract of the antigen stored in the filtered liquid supply main chamber 1 and the small space 6 is naturally filtered or pressure-filtered, and the caries-related bacteria are again put on the filter membrane 3. After being captured, it can be left for a certain period of time, and sufficient extraction can be performed with the extract remaining in the membrane. In this case, the caries-related bacteria are trapped in the internal pores on the filtration membrane 3 in a state of being mixed with the extract, so that the caries-related bacteria are well immersed in the extract until those trapped in the fine parts. Thus, the extraction of the antigen proceeds effectively. The antigen extract contained in the filtration membrane 3 is (1) a recovery solution such as the same composition solution as the extraction solution used is supplied to the filtrate supply main chamber 1 for natural filtration and pressure filtration. It may be collected by absorbing the liquid from the filtrate outlet 2 and backflowing, or (2) disassembling the filtration membrane storage 4 and taking out the filtration membrane 3 and collecting the extract. . According to such a method, the amount of the extract can be minimized, or the composition of the extract can be appropriately adjusted by appropriately selecting the recovered solution. In the above method, the extraction solution can sufficiently act on the caries-related bacteria by leaving it to stand within 1 hour, more preferably 10 seconds to 20 minutes.

  Since the extract obtained by the nitrous acid extraction method is acidic due to the residual acid, when applying the extract to an immunological measurement method, etc., neutralize it with a basic solution as an analytical sample. It is preferable to use it. As the basic solution, aqueous solutions containing various bases such as sodium hydroxide aqueous solution and Tris aqueous solution, or various buffers such as Tris-HCl buffer can be used. These neutralizing solutions may be directly supplied to the filtrate supply chamber and mixed with the extract, or may be mixed in addition to the extract taken out from the filtration device. It is preferable to absorb and mix. In addition, as described above, when the caries-related bacteria are captured on the filtration membrane 3 and then sufficient extraction is performed with the extract remaining in the membrane, this neutralizing solution is used as a solution for recovering the extract. You can use as.

  The antigen concentration contained in the extract thus obtained is included in plaque and saliva by keeping the amount of extraction solution (and recovery solution used as necessary) constant. It has a correlation with the concentration of oral microorganisms.

  FIG. 2 is a schematic diagram showing another embodiment of the filtration device used in the negative pressure filtration method. In this filtration device, almost no space is formed above and below the filtration membrane 3 in the filtration membrane housing portion 4, and the tip of the syringe 9, which is a negative pressure means, is directly on the upper surface of the filtration membrane housing portion 4. The liquid supply chamber to be filtered is formed in the inner space of the syringe outer cylinder 7 so as to be detachable. Such an apparatus has a simple structure, and almost all of the absorbed antigen extract is stored in the inner space of the syringe outer cylinder 7, so that it can be used as an analysis sample. Is efficient in operation.

  1 and 2, the filtrate outlet in the filtration device is a hole and / or notch 11a or 11b (hereinafter also referred to as 11) that communicates the inner and outer surfaces with the filtrate outlet. It is also possible to use one having For example, when the entire amount of the extraction solution or the like is accurately absorbed, the absorption / drainage part 12 of the filtrate discharge port 2 is brought close to the bottom surface of the container containing the extraction solution or the like to absorb the liquid. In such a case, if there is no such hole and / or notch 11 in the filtrate outlet 2, when the extraction solution or the like is absorbed, the inlet / outlet portion 12 of the filtrate outlet 2 is used for extraction. It may stick to the bottom or the like of a container containing a solution or the like, or the gap between the suction / drainage part 12 of the filtrate outlet 2 and the bottom of the container containing an extraction solution may become too small. In such a case, it becomes impossible to absorb the entire amount of the extraction solution, etc., it is necessary to absorb the liquid while checking the amount of absorption, and the operation becomes complicated, or the liquid absorption speed becomes low and the time for the liquid absorption operation May occur. In addition, when a predetermined amount of extraction solution or the like cannot be absorbed, there may be a problem that the amount and concentration of the antigen in the extract obtained due to incomplete extraction vary from one measurer to another. . When the filtrate discharge port 2 is provided with a hole and / or a cut 11 that communicates the inner surface side and the outer surface side of the filtrate discharge port 2, the suction / discharge liquid part 12 of the filtrate discharge port 2 puts an extraction solution or the like. Even when it is close to the bottom of a container, it is possible to secure a flow path for liquid and air during liquid absorption, so even when the liquid volume is small, the entire amount of extraction solution etc. can be absorbed quickly, easily and reliably. can do. Therefore, an antigen extract can be produced quickly, simply and with good reproducibility. Therefore, a highly reproducible measurement result can be obtained, for example, when the amount and concentration of the antigen are measured after the antigen extract is manufactured.

  The shape, number, size, position, etc. of the hole and / or the cut 11 that communicates the inner surface side and the outer surface side of the filtrate discharge port 2 are close to the bottom of the container containing the extraction solution and the like. In this case as well, the flow path of liquid or air can be secured, and it may be appropriately set according to the shape of the bottom of the container containing the extraction solution or the like so that a desired amount of the extraction solution or the like can be absorbed. Examples of the shape of the hole and / or the notch 11 include a curved shape such as a circle, an ellipse, and a semicircle, a polygon such as a triangle and a quadrangle, and a shape such as a slit. Of course, the shape of the filtration device used in the negative pressure filtration method is not limited to that shown in FIGS.

  FIG. 3 illustrates an operation of using the container 13 and the filtration device of FIG. 2 to suck and discharge the extraction solution or the like previously added to the container 13. In the container 13, an extraction part 14 for storing and installing the filtration membrane storage part 4 and the like of the filtration device of FIG. 2 and a curved surface extraction solution having a depth equivalent to the length of the filtrate outlet 2. Etc. are provided with vessel parts 15a, 15b, 15c. The method of using the filtration device of the present invention and the container 13 as shown in FIG. 3 is preferable because a small amount of extraction solution or the like can be absorbed quickly, easily and reliably. In FIG. 3, assuming a method of adding a cleaning solution to the vessel portion 15a, an extraction solution to 15b, and a recovery solution to 15c, the container 13 having three vessel portions is illustrated. What is necessary is just to install required number according to the kind and number of the solutions to be used. Further, the volume, depth, and shape of the vessel portion 15 may be appropriately selected according to the amount of the solution to be absorbed and the length of the filtrate discharge port 2. When the filtration device of the present invention is used, even when the suction / discharge liquid part 12 is close to the container part 15, the hole and / or the notch 11 becomes a liquid or air flow path, so that the liquid can be reliably sucked. It becomes.

  In the description of the negative pressure filtration method described above, caries-related bacteria were measured, and antigen extraction by the nitrous acid extraction method was described as an example. Of course, if necessary, other oral microorganisms may be targeted, or different extracts Or antibodies may be extracted.

  The extraction solution used for the antigen or antibody retentate is described by Jun Nakajima et al. (1988): Extraction / Purification / Analysis I: 14-38. 1. New basic biochemical experiment method Maruzen Co., Ltd., Ogawa Tomoya et al. (1992): Glycotechnology: 282-321. Extraction solutions used in conventionally known solubilization methods and solvent extraction methods described in Sangyo Kenkyukai Co., Ltd. and other extraction solutions used in chemical or biological cutting / decomposition methods Can be used without limitation. Specifically, salt solutions such as magnesium chloride aqueous solution, sodium thiocyanate aqueous solution and guanidine hydrochloric acid aqueous solution used for solubilization and solvent extraction methods; acid solutions such as hydrochloric acid; alkali solutions such as sodium hydroxide aqueous solution; deoxychol Surfactant solution such as sodium acid aqueous solution, octyl glucoside aqueous solution, cetyltrimethylammonium bromide aqueous solution, 3-[(3-colamidopropyl) dimethylammonio] -1-propanesulfonic acid aqueous solution; organic solvent such as n-butanol; Buffer solutions such as glycine hydrochloride buffer, etc. also used for chemical or biological cleavage / degradation methods, nitrous acid aqueous solution; acid solution such as hydrochloric acid; alkaline solution such as sodium hydroxide aqueous solution, protease, phospholipase, etc. Examples thereof include solutions containing the above enzymes.

  The antigen or antibody extract obtained by the negative pressure filtration method has few contaminants, and the antigen or antibody concentration can be constant. Therefore, it is suitable as a sample for measuring the antigen concentration by an immunological method.

  Examples of the immunological method include, as described above, an aggregation method such as a latex method, a radioimmunoassay method, an enzyme immunoassay method, a labeled antibody method, various immunoblot methods such as a Western blot method, and an immunochromatography method. Either method may be used.

  Since the concentration of the antigen or antibody in the extract obtained by the immunological method is proportional to the amount of oral microorganisms that had the antigen or antibody, it adheres to the toothbrush from the concentration of the antigen or antibody. It is also possible to determine the amount of oral microorganisms contained in the plaque and saliva, and to determine the actual concentration in the oral cavity from the concentration.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by a following example.

Production Example 1 [Preparation of purified polyclonal antibody against Streptococcus mutans]
(1) [Preparation of cell sample suspension]
Brain Heart Infusion (hereinafter sometimes abbreviated as “BHI”) (DIFCO) (3.7 g) was dissolved in 100 ml of pure water and then autoclaved to prepare a BHI liquid medium. After culturing Ingbritt (Streptococcus mutans, serotype c) in 2 ml of BHI liquid medium under anaerobic conditions (N ₂ : H ₂ : CO ₂ = 80: 10: 10) at 37 ° C. for 5 hours, the culture solution Was centrifuged at 4000 g for 5 minutes, the medium components in the supernatant were removed, and the cell pellets were collected.

Subsequently, the precipitate was suspended in 5 ml of phosphate physiological saline buffer (pH 7.4) (hereinafter sometimes abbreviated as PBS), and the same centrifugation operation was performed three times to wash the precipitate. Thereafter, the obtained bacterial cell precipitate was suspended in PBS, adjusted to A ₆₀₀ = 1.0, and used as an Ingbritt cell sample suspension. In addition, after ultrasonically treating the bacterial cell sample suspension, it is appropriately diluted and then added to a BHI medium plate, and the number of colonies produced is counted and multiplied by the dilution factor of the bacterial cell sample suspension. The bacterial cell concentration of the sample suspension was determined to be about 1 × 10 ⁹ cells / ml.

(2) [Preparation of antiserum against Streptococcus mutans]
Immunization was performed as follows. That is, in the first week, 0.5 ml of Ingbritt cell sample suspension was injected into the auricular vein to the rabbit 5 times for 5 consecutive days. In the second week, 1.0 ml of the bacterial cell sample suspension was injected into the auricular vein into the rabbit 5 times for 5 consecutive days. In the third week, 2.0 ml of the cell sample suspension was injected into the ear vein of the rabbit 5 times for 5 consecutive days. The fourth week was immunized as in the third week. After confirming the increase in titer by the degree of agglutination reaction of the bacterial cells using a slide glass, blood was collected according to a standard method one week after the final immunization to obtain an antiserum against Streptococcus mutans.

(3) [Purification of polyclonal antibody against Streptococcus mutans]
Ingbritt was cultured at 37 ° C. for 12 hours under anaerobic conditions in 1 L of autoclaved BHI liquid medium. The culture solution was centrifuged at 4000 g for 5 minutes to remove the culture medium component of the supernatant and collect the bacterial cell precipitate. Next, the precipitate was suspended in 100 ml of PBS and subjected to the same centrifugation three times to wash the precipitate.

The Ingbritt cells were washed, suspended in 0.1 M Tris-HCl buffer (pH 8.0), and adjusted to A ₆₀₀ = 15. Pronase (Wako Pure Chemical Industries, Ltd.) was added to this so that it might become 5 mg / ml, and it heat-retained at 37 degreeC for 1 hour. After completion of the reaction, the mixture was centrifuged to collect the cell precipitate. Subsequently, the precipitate was suspended in 20 ml of PBS and subjected to the same centrifugation three times to wash the precipitate. Subsequently, it was washed 3 times with 20 ml of 0.1 M glycine hydrochloride buffer (pH 2.0), and further washed 3 times with 20 ml of PBS to prepare a protease-treated cell suspension (A ₆₀₀ = 12.5).

  Next, the protease-treated cell suspension and 0.5 ml of the antiserum prepared in (2) were mixed and reacted at 4 ° C. for 60 minutes. The mixed solution was centrifuged at 4000 g for 5 minutes to recover the cells. The cells were suspended in 10 ml of PBS and washed by performing the same centrifugation operation three times.

  Next, the cells are suspended in 0.5 ml of 0.1 M glycine hydrochloride buffer (pH 2.0), the adsorbed antibody is eluted, the supernatant is recovered by centrifugation, and 1 M Tris-HCl (pH 9.0) is collected. Was added to adjust the pH to 7.4. The same elution operation was performed 4 times, and the protein amount of each fraction was measured by absorbance at 280 nm.

Next, the eluate was added to a column packed with 1 ml of Protein A-Sepharose (Amersham Pharmacia Biotech) previously equilibrated with PBS, washed 5 ml, and then 5 ml of 0.1 M glycine-hydrochloric acid buffer (pH 3.0). 1M Tris-hydrochloric acid (pH 9.0) was immediately added to adjust to pH 7.4. The eluted fraction of IgG was confirmed by measuring _A280 .

  As a result, 1 mg of a polyclonal antibody obtained by purifying the antiserum (0.5 ml) with protease-treated cells was obtained.

Production Example 2 [Production of immunochromatographic test strip for measuring Streptococcus mutans]
(1) [Preparation of purified polyclonal antibody against Streptococcus mutans labeled with colloidal gold]
2 μl of 100 mM K ₂ CO ₃ was added to 10 ml of a commercially available gold colloid solution (British BioCell International) having a colloid particle size of 40 nm to adjust the pH to 9.0, followed by 0.22 μm filter treatment. The absorbance at 520 nm of the colloidal gold solution was measured and found to be A ₅₂₀ = 1.0.

Next, 64 μl of 2 mM borate buffer solution (pH 9.0) of the polyclonal antibody prepared in (3) of Production Example 1 adjusted to 1 mg / ml was added to the gold colloid solution with stirring, and left at room temperature for 5 minutes. did. Next, 1.1 ml of 10% skim milk-2 mM borate buffer (pH 9.0) was added with stirring (final concentration of skim milk 1%) and left at room temperature for 30 minutes. Next, the reaction solution was centrifuged at 10 ° C., 10000 g for 30 minutes, and after removing the supernatant, 2 ml of 2 mM PBS (pH 7.4) was added to resuspend the lower gold colloid fraction. When the absorbance at 520 nm of the resuspended fraction was measured, A ₅₂₀ = 4.9. The obtained gold colloid fraction (hereinafter sometimes referred to as “gold colloid-labeled antibody”) was stored at 4 ° C.

(2) [Preparation of immunochromatographic test strip]
According to the following method, the immunochromatographic test strips shown in FIGS. 4 and 5 were produced.

  On the detection site 20 and the control judgment site 21 on the nitrocellulose membrane 16 (MILLIPORE, Hi-Flow Plus Membrane, HF180, 25 mm × 6 mm), purified polyclonal prepared in (3) of Production Example 1 of 1 mg / ml, respectively. The antibody and 1 μl of anti-rabbit IgG (H + L) polyclonal antibody (ICN Pharmaceuticals) were spotted and dried in an incubator at 37 ° C. for 60 minutes to immobilize the antibody. The antibody-immobilized membrane 16 was shaken in a 1% skim milk-0.01% Triton X100 aqueous solution at room temperature for 5 minutes. Next, the membrane 16 was taken out in a 10 mM phosphate buffer solution (pH 7.4) at room temperature for 10 minutes and then taken out, and dried in a desiccator for 60 minutes while being sucked with a vacuum pump.

Further, conjugate pad 17 (MILLIPORE, 7.5 mm × 6 mm) was taken out after shaking for 1 minute in 0.5% PVA-0.5% aqueous sucrose solution, and taken out in a desiccator for 60 minutes while sucking with a vacuum pump. Dried. 25 μl of the gold colloid-labeled antibody prepared in (1) of Production Example 2 adjusted to A ₅₂₀ = 1.0 was added to the conjugate pad 17 and dried in a desiccator for 60 minutes while sucking with a vacuum pump. Further, the sample pad 18 (MILLIPORE, 17 mm × 6 mm) was removed after being shaken in a 1% Tween 20-PBS aqueous solution for 1 minute and dried in a desiccator for 60 minutes while being sucked with a vacuum pump. In addition, the absorption pad 19 (MILLIPORE, 20 mm × 6 mm) for holding the test solution after the completion of the development was used as it was untreated.

  Each component of the immunochromatographic test strip prepared as shown in FIG. 4 was placed on a plastic support, and the immunochromatographic test strip shown in FIG. 5 was assembled.

Example 1 [Preparation of antigen extract by negative pressure filtration from plaque suspension adhering to toothbrush after brushing and detection of Streptococcus mutans using immunochromatographic test strip (1)]
(1) [Preparation of specimen]
All tooth surfaces of four different infants (2-3 years old) were brushed with a toothbrush for 60 seconds. Brushing was performed by an adult operator before breakfast. The toothbrush was rinsed with 2 ml of sterilized physiological saline to suspend the plaque and saliva adhering to the toothbrush to prepare a plaque suspension. The plaque suspension was subjected to ultrasonic treatment at 60 W for 20 seconds to obtain a subject 1 containing plaque. The specimen was used immediately after ice cooling. In the same manner, the subject 2 (next day) and the subject 3 (next day) were collected from the same subject on the next day and the second day after the collection date of the subject 1, respectively.

(2) [Measurement of viable count of mutans streptococci in the subject by culture method]
The analyte 1, 2 and 3 prepared according to the method of (1) at each sterilized physiological saline and diluted 10 to 10 ^three times, and plated the dilution 50μl to MSB medium plate, 2 days Candle culture. The number of colonies produced was counted, and the concentration of Streptococcus mutans in the test sample (cfu / ml) was calculated by multiplying by the dilution factor. Streptococcus mutans and Streptococcus sobrinus and some oral bacteria grow on the MSB solid medium. For morphological classification of colonies and colonies that are morphologically indistinguishable, after the colonies are purely cultured, an immunological measurement method using a serotype-specific antibody of mutans streptococci and sugar fermentation Streptococcus mutans was distinguished from Streptococcus sobrinus and other oral bacteria by biochemical methods such as tests, and the concentration of Streptococcus mutans was measured. The results are shown in Table 1.

  The concentration of Streptococcus mutans in the oral cavity varies within the day, but the manner of variation is constant unless sterilization with an antibacterial agent (for example, chlorohexidine) is performed. Therefore, if conditions such as the time for collecting plaque are the same, the Streptococcus mutans concentration is also constant.

  As shown in Table 1, the concentration of Streptococcus mutans ascertained from the test solution obtained by the production method of the present invention is constant regardless of the date of collection and can be measured with good reproducibility. .

(3) [Preparation of antigen extract using filtration device]
The inner side and the outer side of the filtrate outlet as shown in FIG. 6 are communicated with the tip of the filtrate outlet 2 of a 13 mm syringe filter (Whatman, glass fiber filter paper GF / C, particle retention capacity 1.2 μm). The syringe filter 10 was produced by providing two 0.5 mm × 0.5 mm square cuts 11b. A syringe 9 (Terumo, 2.5 ml) was set on the syringe filter 10 to produce a filtration device having the structure of FIG.

  The container 13 shown in FIG. 3 was created. In order to absorb the entire amount of the liquid shown below, the container 13 was set to have a depth of the container portion 15 so that the suction / drainage liquid portion 12 was in contact with the bottom of the container portion 15.

  The plunger 8 is withdrawn from the filtration device, 1.95 ml of the sample collected in (1) of Example 1 is added into the syringe outer cylinder 7, and after the plunger 8 is attached, the plunger 8 is pressed down and pressurized. The saliva was filtered. The filtrate discharged from the filtrate outlet 2 was discarded.

  0.5 ml of 0.1 M NaOH aqueous solution was added to the vessel portion 15 a of the container 13. Similarly, 0.12 ml of 1M sodium nitrite-0.5M acetic acid aqueous solution was added to the vessel part 15b, and 0.38 ml of 0.5M Tris-hydrochloric acid buffer (pH 9.0) was added to the vessel part 15c.

  The syringe filter 10 is installed in the installation part 14 above the container part 15a so that the suction / exhaust liquid part 12 is in contact with the bottom of the container part 15a, and the filtrate of the syringe filter 10 is pulled up to a negative pressure. From the outlet 2, the solution in the vessel 15a was absorbed. The solution was allowed to flow into the syringe outer cylinder 7 as it was, and the plunger 8 was immediately pressed down and pressurized to perform filtration, and the filtrate was discarded. Subsequently, the solution in the vessel portion 15b was sucked in the same manner, and the solution flowing into the syringe outer cylinder 7 was kept as it was at room temperature for 2 minutes. Next, 0.38 ml of 0.5 M Tris-HCl buffer (pH 9.0) was similarly sucked from the filtrate outlet 2, and the extract (about 0.5 ml) was collected in the syringe outer cylinder 7. .

(4) [Measurement of Streptococcus mutans by immunochromatographic test strip]
The syringe filter 10 was removed from the syringe 9 used in (3) above. 0.1 ml of the extract in the syringe 9 is added to the sample pad 18 of the immunochromatographic test strip prepared in (2) of Production Example 2, and the detection site 20 and the control judgment site 21 are colored 10 minutes later. The presence or absence and strength were determined. In the determination, the color intensity of the detection site 20 was visually identified in four levels (++: strong color intensity, ++: medium color intensity, +: weak color intensity,-: no color development). In addition, when the control judgment site | part 21 did not color, it showed that the expansion | deployment of the gold colloid labeled antibody was unsatisfactory, Therefore It analyzed again. The results are shown in Table 2.

  As shown in Table 2, the Streptococcus mutans concentration measured by immunochromatography was also constant regardless of the date of collection. The result of the method was proportional to the result of the culture method. Furthermore, in the immunochromatography method, a result was obtained 15 minutes after the start of measurement, and the result was obtained more quickly than in the culture method.

Comparative Example 1 [Measurement of the number of mutans streptococci in a specimen prepared by brushing the entire tooth surface with a toothbrush and collecting the fallen plaque]
(1) [Preparation of specimen and measurement by culture method]
The teeth of the same subjects A and C as in Example 1 were brushed for 1 minute on the entire tooth surface using a toothbrush. Brushing was performed by an adult operator before breakfast. The test subject's mouth was filled with 5 ml of sterilized physiological saline, and the physiological saline containing the plaque was discharged and collected in a sterilized container. The toothbrush used for brushing was rubbed with the collected physiological saline, and the toothbrush was pressed against the container wall to collect the solution attached to the toothbrush. The physiological saline containing the collected plaque was sonicated at 60 W for 20 seconds to obtain a subject containing plaque. The specimen was cultured immediately after ice cooling by the same method as in Example 1 (2). Samples 5 and 6 were collected from the same subject on the next day and two days after the collection date of subject 4 according to the above method, and the number of mutans streptococci in these subjects was calculated in the same manner as described above. The results are shown in Table 3.
(2) [Measurement of Streptococcus mutans by immunochromatographic test strip]
Analyte extracted from 0.2 ml of the sample collected in (1) by the same method as in Example 1 (3) and analyzed by immunochromatography by the same method as in Example 1 (4) The results are shown in Table 4.

Comparative Example 2 [Measurement of the number of mutans streptococci in subjects prepared by collecting plaque with a cotton swab]
(1) [Preparation of specimen]
From the same subjects B and D as in Example 1, plaque was collected by rubbing the entire tooth surface with a sterilized cotton swab three times. The plaque-adhered swab was vibrated in 2 ml of sterilized physiological saline for 3 minutes to suspend the plaque adhering to the swab. The physiological saline containing dental plaque was subjected to ultrasonic treatment at 60 W for 20 seconds to obtain a subject 4 containing dental plaque. The specimen was used immediately after ice cooling. The specimen was cultured immediately after ice cooling by the same method as in Example 1 (2). Samples 5 and 6 were collected from the same subject on the next day and two days after the collection date of subject 4 according to the above method, and the number of mutans streptococci in these subjects was calculated in the same manner as described above. The results are shown in Table 3.
(2) [Measurement of Streptococcus mutans by immunochromatographic test strip]
An antigen extract was prepared from the specimen (1.95 ml) collected in (1) by the same method as in Example 1 (3), and analyzed by immunochromatography by the same method as in Example 1 (4). The results are shown in Table 4.

  As shown in Tables 3 and 4, Streptococcus mutans bacteria grasped from a specimen prepared by brushing the entire tooth surface with a toothbrush and collecting fallen plaque, or a specimen prepared using a cotton swab The concentration varies greatly depending on the date of collection in both the immunochromatography method and the culture method, and the reproducibility is poor. This is because (1) infants have immature oral function, and it is difficult to swallow the oral cavity without swallowing physiological saline, so the amount of plaque recovered has fluctuated. (2) As described above It is thought that the amount of plaque collected was blurred because it was extremely difficult to wipe all the tooth surfaces evenly with a cotton swab.

It is a perspective view which shows the typical aspect of the filtration apparatus used when extracting an antigen or an antibody from the test liquid obtained with the manufacturing method of this invention. It is a side view which shows another aspect of the filtration apparatus used when extracting an antigen or an antibody from the test liquid obtained with the manufacturing method of this invention. The side surface which shows one aspect | mode of the method of using the filtration apparatus used when extracting an antigen or an antibody from the test solution obtained with the manufacturing method of this invention in combination with the container which hold | maintains the solution for extraction, etc. FIG. It is the schematic of each member of the immunochromatography test strip used in the Example. 1 is a side view of an immunochromatographic test strip used in Examples. FIG. It is an enlarged view of the cut | notch part of the filtrate discharge port of the filtration apparatus used in the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Filtrate supply main chamber 2 ... Filtrate discharge port 3 ... Filtration membrane 4 ... Filtration membrane storage part 5 ... Connection part 6 ... Small space 7 ... Outside a syringe Tube 8 ... Plunger 9 ... Syringe 10 ... Syringe filter 11a ... Hole 11b ... Cut 12 ... Intake / exhaust liquid part 13 ... Container 14 ... Installation part 15a ... Instrument part 15b ... Instrument part 15c ... Instrument part 16 ... Nitrocellulose membrane 17 ... Conjugate pad 18 ... Sample pad 19 ... Absorption pad 20 ... Detection site 21 ... Control judgment part

Claims (1)

  (1) A toothbrush whose entire tooth surface is brushed is brought into contact with a liquid, and plaque and saliva adhering to the toothbrush are dispersed and / or dissolved in the liquid to obtain a test liquid. The test liquid is filtered by a filtration device having a negative pressure means upstream of the filtrate supply chamber, and the filtrate supply chamber and the filtrate outlet are in communication with each other via a filtration membrane. The microorganisms present therein are captured on the filtration membrane, and then (3) the inside of the filtration device is made negative pressure by the negative pressure means, and the extraction solution is sucked from the filtrate discharge port to evacuate the inside of the filtration device. A method for producing an antigen extract for measuring the concentration of microorganisms in the oral cavity, characterized in that the extract of microbial antigen is stored in a filtered liquid supply chamber.

Images