[Selective expansion of human natural killer cells].

BACKGROUND & OBJECTIVE: Natural killer (NK) cells have strong potential of killing tumor cells, but it is difficult to expand sufficient NK cells to satisfy the treatment of tumor. This study was to explore the feasibility of efficiently expand NK cells through co-culturing peripheral blood mononuclear cells (PBMCs) and Wilms tumor cell line HFWT.

METHODS

PBMCs and HFWT cells were co-cultured to expand NK cells. The cytotoxicity of NK cells was measured using 51Cr release assay and crystal violet (CV) staining. The proportions of CD3(+), CD4(+), CD8(+), CD16(+), and CD56(+) cells were detected using flow cytometry.

RESULTS

When PBMCs were co-cultured with irradiated HFWT cells for 10-21 days, NK cells were selectively expanded; the proportion of CD56(+)/CD16(+) cells was over 50%. The NK cells killed more than 80% of fresh HFWT cells at an effector/target ratio of 2. The expansion of NK cells required continuous stimulation of PBMCs by HFWT cells.

CONCLUSION

HFWT cells can effectively stimulating PBMCs to sensitively expand human NK cells for adoptive immunotherapy of human tumors.