Immunogenicity of a soluble membrane antigen from adenovirus-12 induced tumor cells demonstrated in inbred hamsters (PD-4)

Abstract

A soluble antigen was isolated from the cell-membrane fraction of a transplantable adenovirus-12 tumor which had been induced and carried in inbred hamsters for more than 4 years. In this same inbred strain, an immunizing dose–response relationship was determined. As little as 60 μg of the soluble antigen, Ad-12 tumor-specific transplantation antigen (TSTA) given intraperitoneally without adjuvant led to protection of about 50% of challenged hamsters. A single intraperitoneal injection of 90 to 120 μg of Ad-12 TSTA protein, with or without adjuvant, led to protection of inbred hamsters to an inoculum of Ad-12 tumor cells which yielded tumors in 80 to 90% of nonimmunized hamsters. Immunized hamsters did not resist a challenge of 104 SV₄₀-induced tumor cells.