[Anti-tumor mechanisms of Sp2/0 tumor vaccine transfected with mIL-21 gene in mice].

Aim: To explore the anti-tumor mechanism of Sp2/0-mIL-21 tumor vaccine in mice.

Methods: The molecules of MHC-I and CD80 on the surface of Sp2/0-mIL-21 tumor vaccine were detected by flow cytometry (FCM) respectively. A flow cytometric CFSE-7-AAD cytotoxicity assay was used to detect the cytotoxic activities of NK cells and CTLs. The expression of I-TAC in the tumor tissue was tested by RT-PCR.

Results: The expression of MHC-I molecule on the surface of tumor vaccine was up-regulated obviously. The cytotoxic activities of NK cells and CTLs were significantly enhanced in the mice inoculated with Sp2/0-mIL-21 tumor vaccine compared with the mice inoculated with Sp2/0 tumor cell in control group. The expression of I-TAC in the tumor tissue was up-regulated. The histopathologic section analysis showed more lymphocytes were infiltrated in the tumor tissue.

Conclusion: Sp2/0-mIL-21 tumor vaccine can induce strong cell-mediated immune response to tumor cells after it was inoculated s.c into mice. The anti-tumor mechanisms induced by Sp2/0 tumor cell vaccine are associated with the proliferation and activation of T lymphocyte, the differentiation and maturity of NK cell, the infiltration of lymphocytes in tumor tissue, and the enharuement of cytotoxic activities of NK cells and CTLs.