Effect of a B cell mitogen extracted from a fungus Peziza vesiculosa on antibody production in mice.

Abstract

The effect of Vesiculogen (a hot-water extracted B cell mitogen from Peziza vesiculosa) on antibody production in mouse spleens was studied. The number of plaque-forming cells (PFC) elicited by injection with Vesiculogen and/or 2,4,6-trinitrophenyl substituted sheep red blood cells (TNP-SRBC) were comparatively assayed. In the mice injected with 100 micrograms of Vesiculogen (i.p.), an obvious increase in the numbers of anti-SRBC and anti-TNP SRBC PEC in spleens was observed after 2 d of injection, and the numbers of PFC reached a maximum on day 3. Injections to 1-1000 micrograms of Vesiculogen were effective. This effect was shown when Vesiculogen was administered by i.p. or i.v. injections. In some cases, the numbers of PFC in mice injected with Vesiculogen and antigen exceeded the sum of each number of PFC elicited by polyclonal B cell activation activity of Vesiculogen and by antigenic stimulation of TNP-SRBC. Pretreatment with Vesiculogen within 4 d before immunization markedly reduced the PFC response. These results suggest that the effect of Vesiculogen on antibody response in mice attributes to its activities as a polyclonal B cell activator and adjuvant.