Immunologic Responses in Hamsters to Homologous Tumor Antigens Measured in vivo and in vitro

Abstract

Cell mediated immunity against homologous SV₄₀ tumor cells was demonstrable in the homologous in vivo hamster system but not in cell culture. The effectiveness of exudate cells from immunized hamsters was clearly influenced by the ratio of target cells to immune cells and by the age of test hamsters used with protective effect demonstrable in adult but not in 1 week-old hamsters. High levels of immunity against homologous tumor were also demonstrable by direct subcutaneous challenge. The latter system was desirable for assay of vaccine potency because of simplicity and rapidity of obtaining results.