Interferons suppress antibody responses

All three studies used lymphocytic choriomeningitis virus (LCMV) clone 13, which causes a non-cytopathic chronic infection with delayed and weak neutralizing antibody responses in mice. The course of infection was compared with vesicular stomatitis virus (VSV), which is an acute cytopathic virus that triggers a rapid neutralizing antibody response. To ensure that the B cell responses were not due to defects in antigen-specific precursor B cells, the studies used KL25 mice containing an immunoglobulin heavy-chain knock-in and a transgenic light-chain specific for the LCMV glycoprotein.

All three studies found that KL25 B cells adoptively transferred into mice before LCMV infection rapidly (after a few days) declined in number. As LCMV infection is known to be associated with prolonged type I IFN responses, the three groups investigated whether IFN signalling could have a role in suppressing early KL25 B cell responses. Indeed, blocking type I IFN receptor (IFNAR) signalling improved the survival and expansion of KL25 B cells and avoided a biased, unsustainable plasmablast differentiation after LCMV infection.