The use of three co-stimulatory molecules (B7.1, ICAM-1, and LFA-3) in a carcinoembryonic antigen (CEA) recombinant viral vaccine (called TRICOM) was shown to enhance T cell proliferation and confer an overall survival advantage in CEA+ tumor-bearing mice compared to vaccination with only one or none of these molecules [147]. The gene discussed is CEACAM5; the disease is neoplasm.