An investigation of the T cell requirements of in vitro antibody forming B cells detected by the ELISPOT assay and a comparison with antibody synthesis.

ABSTRACT

We have studied the primate cellular requirements in the antibody forming cell (AFC) assay, using a 185,000 molecular mass streptococcal antigen. Cultures of B cells alone stimulated with the antigen were unable to develop into AFC. Reconstitution of B cells with T cells resulted in a significant increase in the number of AFC. However, CD4 cells were more efficient than T cells in helping the antibody response and CD8 cells failed to induce B cells to synthesise antibody. A comparison between the specific IgG antibody synthesis and the number of AFC detected by the ELISPOT method showed a highly significant correlation between the number of AFC and the amount of specific IgG antibody. We suggest that the AFC (ELISPOT) assay can be readily used to investigate B cell interactions with T cell subsets.