Search

Objective: To explore the killing effect of CAR (CD138-CD28-CD3ζ)-NK cells on myeloma cells through construction of CAR(CD138-CD28-CD3)-NK cells., Methods: The antiCD138scFv-CD28-CD3 zeta plasmid pcDNA3.1 was constructed, which then together with 3 plasmid lentiviral packaging system were transfected into 293T cells, the virus was collected. Furthermore, in order to get the stably transfected cell line, the NK92MI cell line was infected by the virus, then the positive cells were screened by puromycin. The expression of the CARNK cells were verified by RT-PCR and Western blot. At last the ability of secreting cytokine CD107a was detected by flow cytometry, and the statistical analysis was carried out to verify the anti-myeloma effect of CAR-NK cells., Results: Gene fragment of the CAR(antiCD138scFv-CD28-CD3ζ) was constructed successfully by gene engineering technique in vitro, and the gene sequence was verified to be correct by sequencing. By virus packaging technology, the virus expressing the protein of the CAR was obtained. PCR and Western blot verified the expression of CAR fusion protein on the sufurce of NK cells. The cell killing experiment confirmed that the CAR-NK cells possessed the ability to secrete cytokine CD107a superior to control cells and showed the obvious killing effect on multiple myeloma cells., Conclusion: The CAR can be constructed in vitro, and express on NK92 cells. The CAR-NK cells can kill the multiple myeloma cells expressing CD138 antigen, thereby plays an antimyeloma effect.

Natural killer (NK) cells can suppress the development of graft vs host disease (GVHD) while retaining antitumor response in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Sphingosine-1-phosphate receptor 5 (S1PR5) can regulate NK cell migration and distribution in vivo by interacting with sphingosine-1-phosphate (S1P). This study was aimed to investigate S1PR5 expression change of NK cells in allo-HSCT and to explore the relationship between S1PR5 change and frequency of acute/chronic graft-versus-host disease (aGVHD/cGVHD). The S1PR5 expression was detected by real time quantitative PCR in the RNA extracted from blood NK cells of 17 couples of donor and recipient one month after allo-HSCT. The results showed that S1PR5 mRNA level variations in NK cells of donors and recipients post-allo-HSCT were not statistically significant (0.235 ± 0.191 vs 0.330 ± 0.261, P > 0.05). S1PR5 expression of NK cells was significantly lower in patients with aGVHD than those in patient without aGVHD (0.973 ± 0.834 vs 6.166 ± 5.32, P < 0.05). Compared with the corresponding donor, S1PR5 expression levels of patient declined by more than 10 that caused the high incidence of aGVHD. No significant correlation was found between S1PR5 expression of NK cells and cGVHD (3.401 ± 2.324 vs 2.762 ± 1.972, P > 0.05). It is concluded that the decreased expression level of NK cells S1PR5 is associated with aGVHD occurrence. Possible mechanism is due to S1PR5 low expression affecting distribution of NK cells in vivo, so affecting the regulation of NK cells for aGVHD.