SOCS1拮抗物pJAK2多肽可增强树突状细胞的抗肿瘤作用

pJAK2 polypeptide,an antagonist of suppressors of cytokine signaling-1,can enhance the antitumor effect of dendritic cells

目的:探讨细胞因子信号转导抑制因子-1(suppressors of cytokine signaling1,SOCS1)拮抗物pJAK2多肽(氨基酸序列号为1001-1013)参与树突状细胞(dendritic cells,DCs)的体外诱导培养后对DCs抗肿瘤作用的影响。方法:采集健康人外周血,离心获得单个核细胞,用重组人粒细胞巨噬细胞集落刺激因子(recombinant human granulocyte-macrophage colony stimulating factor,rhGM-CSF)及重组人白细胞介素-4(recombinant human interleukin-4,rhIL-4)诱导DCs,第5天分为4组:单纯DCs培养(对照)组、抗原负载(Lysate-DCs)组、多肽修饰(pJAK2-DCs)组和抗原与多肽共培养(Lysate+pJAK2-DCs)组,第6天各组加入肿瘤坏死因子-α(tumor necrosis factor-alpha,TNF-α)促成熟。倒置显微镜下观察DCs形态;FCM法检测DCs表型;乳酸脱氢酶(lactate dehydrogenase,LDH)细胞毒实验检测各组细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)对胃癌细胞BGC-823的靶向杀伤作用;ELISA法检测白细胞介素-12(interleukin-12,IL-12)和γ干扰素(interferon-γ,IFN-γ)的水平。结果:与未加入诱导剂组相比,各组均成功诱导出成熟DCs,均高表达CD80、CD83、CD86和人类白细胞DR抗原(human leukocyte antigen DR,HLA-DR),但以Lysate+pJAK2-DCs组的表达水平最高。在10:1～30:1的效靶比范围内,CTL杀伤作用与效靶比呈正相关。当效靶比为30:1时,对照组的CTL杀伤率达(19.77±2.34)%,低于其他3组(P<0.01),而Lysate+pJAK2-DCs组较Lysate-DCs组及pJAK2-DCs组都高(P<0.05)。Lysate+pJAK2-DCs组培养上清液中IL-12及IFN-γ的分泌水平明显高于对照组(P<0.01)。结论:SOCS1拮抗物pJAK2多肽(1001-1013)可增强DCs对胃癌细胞的抗原递呈及特异性抗肿瘤作用。

To investigate the effect of pJAK2 polypeptide, an antagonist of SOCS1 （suppressors of cytokine signaling 1）, on antitumor effect of in vitro cultivation-induced DCs （dendritic cells）. Methods： Peripheral blood was collected from the healthy volunteers, and the PBMCs （peripheral blood mononuclear cells） were isolated. DCs were induced by rhGM-CSF （recombinant human granulocyte-macrophage colony-stimulating factor） and rhlL-4 （recombinant human interleukin-4）. On the fifth day, DCs were divided into four groups： control group, Lysate-DCs group, pJAK2-DCs group, and Lysate ＋ pJAK2 DCs group. On the sixth day, TNF-~ （tumor necrosis factor-alpha） was added into each group. The morphological features of DCs were observed under an inverted microscope; the phenotypes were detected by FCM （flow cytometry）; the killing effect of CTLs （cytotoxic T lymphocytes） on gastric cancer BGC-823 cells was evaluated by LDH （lactate dehydrogenase） cytotoxicity test; the concentrations of IL-12 （interleukin-12） and IFN-y （interferon-y） were detected by ELISA （enzyme-linked immuno sorbent assay）. Results： Mature DCs presented typically morphological and phenotypic features; the DCs in Lysate ＋ pJAK2-DCs group had the highest expression levels of CD80, CD83, CD86 and HLA-DR （human leukocyte antigen DR）. When the ratio of effectors to target cells ranged from 10 ： 1 to 30 ： 1, the killing activity of CTLs had a positive correlation with the ratio. When the ratio of effectors to target cells was 30 ： 1, the killing activity of CTLs in the control group was （1 9.77_＋2.34）%, which was lowest as compared with the other groups （P 〈 0.01）, meanwhile the killing activity of CTLs in Lysate ＋ pJAK2-DCs group was higher than those in Lysate-DCs and pJAK2-DCs groups （P 〈 0.05）. The levels of IL-12 and IFN-y secretion in Lysate ＋ pJAK2-DCs group were apparently higher than those in the control group （P 〈 0.O1）. Conclusion： An antagonist of SOCS1, pJAK2 polypeptide, can enhance the ability of antigen presentation and specific antitumor effect of DCs on gastric cancer cells.