Effect of TKD-activated NK cells on tumor growth inhibition of human pancreatic carcinoma in nude mice / 中国免疫学杂志

ABSTRACT

Objective:To investigate the antitumor effect of TKD-activated NK cells on tumor growth inhibition of human pancreatic carcinoma in nude mice .Methods:CD3-CD56+NK cells were obtained from human peripheral blood mononuclear ( PBMC) in stem cell growth medium SCGM , 2 μg/ml TKD was added to the medium on day 10.The activating receptor CD 94/NKG2C expression levels on NK cells was detected with FAC after 4 days.The cytolytic activity of TKD-activated NK cells against human pancreatic carcinoma subline with HSP 70 expression on their cell surface was analyzed by MTT assay .Established a new model of orthotopic-transplantation tumor of human pancreas .NK cells were injected i.v.into the tail vein of tumor-bearing mice on day 15,the antitumor activity of the NK were evaluated .The capacity to infiltrate Colo 357 tumors in SCID/beige mice was detected with Immunohis-tochemistry.Results:Flow cytometry analysis showed that CD3-CD56+NK cells could expanded in SCGM medium ,and the average percentage of NK cell was (87.50 ±1.35 )%.CD94 expression levels on NK cells increased obviously ,the mean fluorescence intensity of CD94 was(220.56±1.82),compared to (68.72±1.85)of control group cell.The cytolytic activity against HSP70 membrane-positive pancreatic carcinoma sublines Colo 357 cells was high and there was significantly statistical difference between TKD-activated NK cells and unactivated NK cells.The cytolytic activity was(68.72±2.55)%when ratio of effector cells and target cell was 401.TKD-activated NK cells had a stronger suppressive effect on tumor growth in BALB /c nude mice bearing Colo 357 cells in vivo ,Median inhibitory rates was ( 61.3 ±1.5 )% .There was significant statistical difference compare to control group ( P <0.01 ) .The result of Immunohistochemistry indicated that predominantly NK cells induced with TKD had the capacity to infiltrate Colo 357 tumors in SCID/beige mice.Conclusion: TKD-activated NK cells are highly efficient cytolytic effector cells which have a stronger significant suppression against pancreatic carcinoma growth in vivo .