Suppression of anti-hapten (TNP) antibody response by suppressor T cells and their product. The role of macrophages.

The effect of the lymphocytes from picryl sulfonic acid treatment animals on primary and secondary humoral immune response to TNP hapten was investigated. These cells known to inhibit contract sensitivity reactions were also able to depress primary IgM response. When peritoneal exudate cells from normal mice incubated in suppressor supernatant were transferred into primed mice the suppression of IgM but no IgM secondary response was observed. In contrast peritoneal exudate cells incubated in control supernatant augmented IgM but didn't affect IgG response. It is postulated that normal peritoneal exudate cells (presumably macrophages) can stimulate IgM response. This enhancing activity could be partially blocked by soluble suppressor factor.