[Establishment of a novel culture system for specific expansion of human gamma delta T cell and study of its biological properties]

Abstract

Objective: To study the specific expansion method of human gamma delta T cell and the molecular mechanism against tumor cells.

Methods: The peripheral blood mononuclear cells were co-cultured with XG-7 cells as stimulating cells and activated for the expansion of gamma delta T cells. Immunophonotype was analysed by IIFA and FACS. The cytotoxicity of gamma delta T cell against tumor cells was measured by 51Cr four hour release assay.

Results: When this novel culture system was used, gamma delta T cells mainly expressing V gamma 9/V delta 2 encoded TCR were selected and expanded rapidly from 4.8 +/- 3.4% to 46.2 +/- 8.3%. With exogenous interleukin-2, gamma delta T cells were expanded in large quantity 10(10) within 3 weeks. gamma delta T cells mediated strong cytotoxic activity to different tumor cells including K562, Daudi, XG-7 cell lines, but no cytotoxic activity to normal cells was observed. XG-7 cells expressed HSP molecules and anti-HSP in mAB blocked the proliferation of gamma delta T cells.

Conclusion: The method shows unique biological properties: brief, rapid, well-repeating and wide cytotoxic activity against tumor cells. So gamma delta T cells are of value in tumor adoptive immunotherapy.