Abstract: | The dependence of the production of antibody-forming cells (AFC) and non-specific immunoglobulin-forming cells (nIFC) on the doses of T-dependent (sheep red blood cells, SRBC) and T-independent (polyvinylpyrrolidone, PVP and pneumococcal polysaccharide SSS III) antigens was investigated. The immunization of BALB/c mice with immunogenic or subimmunogenic doses of SRBC and PVP induced a marked increase in the number of antigen-dependent nIFC. In contrast, the injection of any SSS III doses did not influence the amount of nIFC, although a specific immune response to SSS III was quite obvious. Thus, two T-independent antigens, type II, differ in their ability to induce non-specific immune reactions. The experiments on simultaneous administration of monoclonal anti-Thy-1.2 antibodies and PVP or SSS III to mice have demonstrated that these differences were not related to T-suppressor activity. The possible role of T helpers in the immune response to T-independent antigens is discussed. |