K562 Feeder Cells Promote The Expansion And Cytotoxicity Of INKT Cells

Invariant nature killer T cells(iNKT cells)play an important role in cancer adoptive cell immunotherapy,its curative effect is directly related to cell numbers and cytotoxicity.In order to study the effects of the genetic modified K562 cells overexpression of CD8a-IL21?CD 14?CD 19?CD86?CD 163 and CD 13 7L(hereinafter called the K562 feeder cell)on iNKT cell expansion and cytotoxicity.The peripheral blood mononuclear cells(PBMC)from healthy volunteers were isolated and stimulated with K562 feeder cells combined the traditional IL-2 and a-galactosylceramide.The cell culture without K562 feeder cell as control group.Proliferated cells were counted and the iNKT cell phenotype were determined by Flow cytometry analysis.Then the cytotoxicity of expanded iNKT cells to K562,PC3,A549,HepG2 cells was examined by CFSE/7-AAD assay.A PC3Fluc cell tumor mouse model was established and treated with iNKT cells adoptive immunotherapy,the therapeutic effect was observed by the IVIS Lumina Imaging System.After culturing for two weeks,the number of iNKT cells stimulated with K562 feeder cells was 22 times higher than control group;The purity of the iNKT cells increased from 1%to 98.5%;meanwhile the cytotoxicity to K562,PC3,A549,HepG2 cells was significantly enhanced;Animal experimental results showed that the iNKT cells stimulated with K562 feeder cells significantly improved the cure rate and survival rate of the tumor-bearing mice.In this study,we cultured iNKT cells with K562 feeder cells in order to get the cells have a large number,high purity and strong cytotoxicity,which was enough to meet the clinical requirement.