Abstract
Tumor-specific immunity mediated by thymus-derived lymphocytes (T cells) was established in C3H/He mice against syngeneic X5563 plasmacytoma. Splenic T cells from mice, which exhibited resistance to tumor challenge, revealed a potent in vivo tumor-neutralizing activity as well as in vitro cytotoxicity. In contrast, spleen cells from mice 7 days after tumor cell inoculation (7-day tumor-bearing mice) exhibited no protective activity when assayed by in vivo tumor-neutralization test, whereas these cells exhibited almost comparable in vitro cytotoxic activity to that from the tumor-resistant mice. Any suppressor cell activity was not detected in 7-day tumor-bearing animals. While a slight in vivo protective activity was observed in the spleen cells from 14-day tumor-bearing mice, this activity was still significantly weaker than that of spleen cells from mice similarly inoculated with tumor 14 days before but whose tumor had been removed 7 days before the assay. The development of in vivo protective immunity in tumor-resected mice was suppressed by intravenous inoculation with 7000 R X-irradiated tumor cells. These results indicate that in vitro reactivity of immune T lymphocyte population is not always correlated with in vivo protective immunity, but there is a substantial decrease in in vivo immune capability of T cells from tumor-bearing animals, and that this suppression may be ascribed to the presence of a large amount of tumor-associated transplantation antigens rather than to suppressor cell activity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.