[Studies of mouse interleukin-2 gene therapy for head, and neck sequamous cell carcinoma using polycationic liposome-mediated transduction].

OBJECTIVE

To investigate the immunological mechanism of mouse IL-2 gene therapy and the optimal lipid to DNA ratios of lipid-DNA complexed (lipoplexes) by using polycationic liposome-mediated Tumors were established in the transduction for head and neck squamous cell carcinoma (HNSCC).

METHODS

floor of mouth in C3H/HeJ immunocompetent mice with SCCVII cell line. Lipoplexes with various lipid to DNA ratios (L:D) and naked DNA were transducted in vivo by direct intratumoral gene transfer and in vitro. The supernatants of SCCVII cell and tumour tissues were collected for IL-2 expression by enzyme-linked immunosorbent assay. Natural killer (NK) cell activity and cytotoxic T-lymphocyte (CTL) activity were also The optimal L:D ratio for IL-2 expression in vitro was not assayed by lactate dehydrogenase method.

RESULTS

consistent with that in vivo. By use of lipoplexes with L:D = 3:1, higher IL-2 expression of tumor tissues and greater activities of NK cell and CTL of murine spleen were noted in the treated group as compared with those A comparison of naked plasmid and lipid-complexed found in naked DNA and empty plasmid (EP).

CONCLUSION

DNA revealed that lipoplexes were more effective for intratumoral gene transfer to HNSCC. The results indicate that the formulation and dosage of polycationic L:D complexes play a key role in determining the level of intratumoral transgene expression.