Both irradiated and non-irradiated tumour-bearing mice showed an increased quantity of kappa IgG2a (65 ±46 pg/mL) as compared to kappa IgG1 (14 ±26 pg/mL), IgG2b (12 ±22 pg/mL) and IgM (17 ±14 pg/mL). The gene discussed is CD40LG; the disease is neoplasm.