Spontaneous mouse mammary tumor cell lysates induce IgG production in spleen mononuclear cells of healthy and tumor-bearing mice

ABSTRACT Background. We hypothesized that Tumor cell lysate (TCL) prepared from spontaneous mouse mammary tumor (SMMT) may elicit IgG production by spleen mononuclear cells (SMCs) in ex vivo. Methods. The SMCs from healthy mice (HM, n = 6) and four-week SMMT-bearing mice (TBM, n = 6) was cultured in presence of TCL and mitogen for 42 hr at 37°C, separately. Serum and SMCs culture supernatant levels of IFNγ, IL-4, and total IgG were measured using special ELISA kits. Results. Serum IgG level of TBM was significantly higher than that of HM group (P = 0.019), while serum IFNγ and IL-4 did not differ between two groups (P > 0.05). Mitogen significantly induced ex vivo production of both IFNγ (P = 0.013) and IL-4 (P = 0.015) by SMCs from HM group, and only IL-4 (P = 0.049) by SMCs from TBM group. In contrast, TCL increased ex vivo production of IgG by SMCs from both HM (P = 0.034) and TBM (P = 0.016) groups. The ex vivo IgG revealed a moderate positive correlation with tumor size (r = 0.578, P = 0.422). Conclusion. It seems that TCL prepared from SMMT are potent inducers of IgG production. This may propose TCL as a potential tool for monitoring of humoral immunity in animal models.