Synthetic antigens III. Antigen-binding cells to interpolymer of styrene and maleic acid PSM and sheep red blood cells in mice immunized with PSM.

Studies on the immune response in mice to a new synthetic antigen interpolymer of styrene and maleic acid (PSM) are described. The immune response was measured by determination of antigen binding cells by means of rosette test with PSM-coated SRBC, An unexpected effect was observed--besides rosette-forming cells for PSM, rosette-forming cells and agglutinating antibodies for sheep red cells were found. The results presented in this paper suggest that PSM is acting both as an immunogen and a polyclonal B-cell activator. As a polyclonal B-cell activator, PSM might stimulate the immune response to sheep red blood cells. However, in the case of PSM, in contrast to other polyclonal B-cell activators, this response is suppressed and delayed. The suppression may be caused by suppressor T-cells generated by PSM or by blockade by PSM of antigen-binding cells and antibody-forming cells for sheep red blood cells. The mechanism of the effect observed is discussed.