In a follow up report, anti-Tn-PS A1 sera containing the Tn specific IgG3 antibody was analyzed for the ability to recognize cancer cells using flow cytometry (FACS) [93] and it was revealed that the IgG3 antibody binds to Tn expressed on human tumor cell lines such as MCF 7, MDA-231, Jurkat (leukemia) and Panc-1 (pancreas). The gene discussed is IGHG3; the disease is cancer.