The experimental study of the biological activity and anti-tumor effects of CD_3AK cells in human umbilical cord blood
Wei Xucang1, Xing Peini1, Zhao Wenli1, Zhai Xinhui1, Li Meisheng1, Guo Liang2 (1. Department of Hematology Shaanxi Provincial People's Hospital, Xi'an 710068; 2.Division of Hematology, Xi'an Central Hospital, Xi'an 710003, China)
Objective To induce human mononuclear cell of cord blood into CD 3 activating killing (CD 3AK) cells with anti-CD 3 monoclonal antibody (CD 3McAb) and recombinant human interleukin-2 (rhIL-2), so that their proliferative activity, activity of killing action, phenotypes and level of secretory cytokines can be observed dynamically. Methods The increase of the number of cells was counted by Tapan-blue staining. The killing action can be measured by using methyl -thiazolyl-tetrazolium-array. The phenotypes of cells were analysed by using indirect immunofluorescence assay. The levels of IL-6, interferon-γ (IFN-γ) and tumor necrotic factor-α (TNF-α)in culture supernatants were analysed by using enzyme-linked irnmunosorbent assay(ELISA). Results The increase of the number of CD 3AK cells from cord blood was the highest amounting to 78.56 times in the second week. The killing action reached the peak on day 12, and all target cells (malignant cell lines) could be killed significantly. The heterogeneous phenotypes of CD 3AK cells showed that the number of cells with CD 3+, CD 8+, CD 25+, CD 38+, CD 16+ and CD 56+ increased significantly on day 7,14 compared with those of pre-culture (P 0.01). The levels of IL-6, IFN-γ and TNF-α in CD 3AK cells in culture supernatants increased noticeably on day 3. Conclusion CD 3AK cells from cord blood are very strong proliferative immune cells with wide-spectrum killing activities of tumor cells. The research provides theoretical and experimental basis for the immunotherapy of CD 3AK cells in cord blood.