The mode of action of mycobacterial adjuvants. III. The clonal nature of antibody formation and the effect of mycobacterial adjuvant on antibody-forming cell clones.

Localization of 19S and 7S plaque forming cells detected by Jerne plaque technique were examined in the spleens of irradiated recipient mice transferred with a limiting number of spleen cells and SRBC. All the plaques within a single colony were homogeneous in size and appearance. This supports the clonal nature of antibody formation. An addition of a mycobacterial adjuvant, wax D, to the sensitizing antigen, SRBC, caused an increase in the number of clones (colonies) developing large plaques. It is suggested that there may be normally available competent precursors for clones developing large plaques and the precursors may specifically increase in number in the presence of the adjuvant.