摘要:
Objective To observe the effect of immunotherapy on hepatocellular carcinoma (HCC) by melanoma-associated antigen-A3 (MAGE-A3) activated dendritic cells (DC)-induced antigen-specific CD8+ cytotoxic T lymphocytes (CTL) and offer help to HCC treatment.Methods After MAGE-A3 activated DC biomarkers, interleukin (IL)-12, and IL-10 in DC were tested.MAGE-A3-DC was used to induce antigen-specific CD8+ CTL.The apoptosis of L02 cells and HepG2 cells was detected after treatment with CD8+ CTL.Interferon (IFN)-γ of CD8+ CTL was detected by enzyme-linked immunospot assay (ELISPOT).Subcutaneous tumor model of mouse HCC was established.The tumor volume of different groups was measured.Tumor tissue was further observed by pathological sections.Results MAGE-A3 protein stimulation significantly increased the levels of Human leukocyte antigen-DR (HLA-DR), DC83, DC86 and DC80 markers on the surface of DC (97.45±2.58 vs.48.33±1.68, 92.81±2.36 vs.52.92±1.90, 94.00±3.01 vs.53.97±2.05, 92.16±1.87 vs.34.13±1.32;t=35.680,P=0.013;t=29.440,P=0.021;t=24.580,P=0.012;t=56.690,P=0.009).The IL-12 level of MAGE-A3-DC was significantly higher than that of DC [(338.44±18.15) pg/ml vs.(243.23±16.56) pg/ml;t=8.670,P=0.005], but IL-10 level of MAGE-A3-DC was significantly lower than that of DC [(207.21±10.89) pg/ml vs.(327.58±14.36) pg/ml;t=14.930, P=0.009].The apoptosis of L02 cells treated with MAGE-A3-DC-CD8+ CTL was similar to that after treatment with DC-CD8+ CTL [(9.10±1.40)% vs.(9.71±1.58)%;t=0.650, P=0.120].The apoptostic rate of HepG2 cells treated with MAGE-A3-DC-CD8+ CTL was significantly higher than that after treatment with DC-CD8+ CTL [(58.84±5.27)% vs.(9.63±1.61)%;t=19.970, P=0.008].After therapy, tumor sizes V/V0 in MAGE-A3-DC-CD8+CTL group decreased significantly as compared with those of phosphate buffer (PBS) group and DC-CD8+ CTL group (5.43±1.22 vs.21.81±2.01 vs.22.85±2.40;t=22.030, P=0.010;t=20.460, P=0.012).Hematoxylin and eosin (HE) staining showed that nuclear condensation, increased cell gap, vacuoles, and edema were observed in tumor tissues after treatment with MAGE-A3-DC-CD8+ CTL, but pathological changes of tumor tissues were not observed in PBS group and DC-CD8+ CTL group.Conclusion MAGE-A3 protein can stimulate the maturation of DC that induce the production of MAGE-A3 specific CD8+CTL.MAGE-A3-DC-CD8+CTL have specific tumor killing ability.%目的 探讨黑色素瘤相关抗原-A3(MAGE-A3)蛋白激活树突状细胞(DC),然后诱导产生CD8+细胞毒T淋巴细胞(CTL)进行免疫治疗肝细胞癌(简称肝癌)的效果.方法 利用MAGE-A3蛋白诱导DC成熟并检测DC表面标志物及白细胞介素(IL)-10、IL-12表达,然后利用成熟的MAGE-A3-DC诱导MAGE-A3特异性CD8+CTL,并检测MAGE-A3-DC-CD8+CTL 对正常肝细胞L02和肝癌细胞HepG2的杀伤作用.建立BALB/c-nuu肝癌模型,检测MAGE-A3-DC-CD8+CTL对小鼠肿瘤的抑制作用,并通过病理学切片观察肿瘤组织变化.结果 MAGE-A3蛋白刺激能够显著上调DC表面标志物DC80、DC83、DC86和人类白细胞抗原DR基因(HLA-DR)水平(97.45±2.58 比48.33±1.68,92.81±2.36比52.92±1.90,94.00±3.01比53.97±2.05,92.16±1.87比34.13±1.32;t=35.680,P=0.013;t=29.440,P=0.021;t=24.580,P=0.012;t=56.690,P=0.009);与磷酸盐缓冲液(PBS)刺激的DC比较,MAGE-A3蛋白能够显著促进DC释放IL-12[(338.44±18.15)pg/ml 比(243.23±16.56)pg/ml;t=8.670,P=0.005]和显著抑制IL-10的释放[(207.21±10.89)pg/ml比(327.58±14.36)pg/ml;t=14.930,P=0.009].MAGE-A3-DC-CD8+CTL和DC-CD8+CTL展示了相近的L02细胞杀伤效果[(9.10±1.40)%比(9.71±1.58)%;t=0.650,P=0.120],与DC-CD8+CTL 比较,MAGE-A3-DC-CD8+CTL展示了显著的HepG2细胞杀伤效果[(58.84±5.27)%比(9.63±1.61)%;t=19.970,P=0.008].BALB/c-nuu肝癌小鼠经过MAGE-A3-DC-CD8+CTL治疗后,肿瘤体积比显著低于PBS组和DC-CD8+CTL组(5.43±1.22比21.81±2.01比22.85±2.40;t=22.030,P=0.010;t=20.460,P=0.012).苏木素-伊红(HE)染色结果显示,经过MAGE-A3-DC-CD8+CTL处理的肿瘤组织细胞核固缩,细胞间隙增大,出现空泡和水肿现象,而PBS组和DC-CD8+CTL组肿瘤组织无病理学改变.结论 MAGE-A3蛋白能够刺激DC细胞成熟并诱导产生MAGE-A3蛋白特异性CD8+CTL,MAGE-A3-DC-CD8+CTL具有特异性的肿瘤杀伤能力.