IgM Participation in Tumor Rejection by Immunized MICE

Abstract

IgG and IgM participation in tumor rejection was studied in DBA/2 mice immunized against L1210 leukemia and in Swiss mice immunized against Ehrlich adenocarcinoma. In both the systems, IgM globulins seem to be implicated and are present on the cell surface of macrophages, lymphocytes and cancer cells, while IgG globulins are present only on some lymphocytes. IgM are also present in the peritoneal washing fluids (obtained 24 h after the injection of viable tumor cells) of both previously immunized mice and those of the control group. In the former group, protein content is about three times higher than that in the control group, while the relative amount of heavy proteins (18 S) and light proteins (7 S) is quite similar. These observations are discussed, as is the possibility that some complement components as C'3 may participate in the reaction.