[Alloreactive NK cells enhance the effect of donor lymphocyte infusion in the management of relapsed lung cancer after haploidentical hematopoietic stem cell transplantation].

This study was aimed to study the potential effects of alloreactive NK cells (allo-NKs) in therapy of relapsed lung cancer after haploidentical hematopoietic stem cell transplantation using donor lymphocyte infusion (DLI). The F1 donors derived-NK cells were purified with MACS magnetic separation system, in which the proportion of the alloreactive Ly49A(+) cells was detected by flowcytometry and alloreactivity was measured by LDH method. The relapse model of lung cancer after haploidentical-HSCT was established. The distribution kinetic of infused donor lymphocytes in vivo was analyzed. The inhibition of relapse tumor, infiltration of lymphocytes in situ and fluctuation of 22 kinds of cytokines in serum after DLI were compared among different groups. The results showed that the infused donor cells of allo-NK group were accumulated mostly in lung, spleen and kidney for more than 48 hours with considerable higher levels according to the distribution kinetic curve. The sizes of relapse tumors between chemotherapy + PBS group and chemotherapy + DLI group showed no difference. However, the relapsed tumors in allo-NK + DLI group were significantly smaller than that in chemotherapy + DLI group or allo-NK + PBS group, in which increased infiltration of lymphocytes were defined in situ. The levels of cytokines such as MCP-1, IL-17, IL-12 and MCP-5 in serum of allo-NK + DLI group ascended compared with control group, though the level of IL-10 declined simultaneously. It is concluded that allo-NKs prolong the survival time of infused donor lymphocytes in vivo, promote the secretion of inflammatory cytokines and Th1-type of cytokines, and further improve the antitumor effects of DLI against relapse after transplantation.