异种黑色素瘤相关抗原诱发抗肿瘤免疫伴发自身免疫性损伤

目的探讨腺病毒载体(Ad)介导异种黑色素瘤相关抗原酪氨酸酶相关蛋白2(TRP2)诱发抗肿瘤免疫与自身免疫性损伤的关系。方法用Ad编码的人或小鼠TRP2(AdhTRP2或AdmTRP2)皮内免疫C57BL/6小鼠,将小鼠分为正常对照组(d1703)、AdhTRP2和AdmTRP2免疫组。体内细胞毒性T淋巴细胞(CTL)杀伤试验和细胞内干扰素γ(IFNγ)染色(ICS)分析CTL杀伤活性和IFN-γ的产生(每组3只小鼠);皮下接种B16.F10黑色素瘤细胞(每组10只小鼠),观察荷瘤小鼠成活情况。结果AdhTRP2诱发小鼠CTL杀伤活性与免疫时间相关,免疫后1周活性达到最大,随后逐渐降低;AdhTRP2诱导的CTL杀伤活性具有剂量效应关系。AdhTRP2免疫小鼠1周其6hCTL杀伤率为94%±5%,脾脏产生IFNγ的CD8+T细胞占总CD8+T细胞的0.87%±0.12%,而相应地AdmTRP2分别为22%±8%和0.15%±0.05%。接种1×106B16.F10细胞,AdhTRP2免疫的小鼠观察3个月100%无瘤生长,但在病毒注射部位有白癜风形成;而接种1×105B16.F10细胞的AdmTRP2免疫小鼠3个月只有20%的成活率,并不伴局部白癜风形成。结论用Ad介导异种TRP2能有效地打破对自身TRP2的免疫耐受,诱发强烈的抗原特异性细胞免疫反应,同时伴发自身免疫性损伤。

Xenogeneic melanoma-related antigen elicits anti-tumor immune response, companied by autoimmune injury

OBJECTIVE: To investigate the relationship between anti-tumor immune response and autoimmunity elicited by adenovirus-mediated xenogeneic melanoma-related antigen tyrosinase-related protein 2 (TRP2). METHODS: Mice divided into three groups were intradermally immunized by dl 70-3 (control group), Ad hTRP2, and Ad hTRP2 respectively. Analysis of the killing activity and production of interferon (IFN) gamma of tumor-specific cytotoxia T lymphocytes (CTL) from the C57BL/6 mice (3 mice per group) immunized with adenoviral vector encoding human or murine TRP2 (Ad hTRP2 or Ad mTRP2) were made using in vivo CTL and intracellular staining of IFN-gamma respectively. Additionally, the survival of mice (10 mice per group) immunized with Ad hTRP2 or Ad mTRP2 was checked after the subcutaneous inoculation with mouse melanoma B16.F10 cells. RESULTS: The CTL lysis activity elicited by Ad hTRP2 was related to the duration of immunization, which increased up to peak one week after the immunization and subsequently decreased. Moreover, the Ad hTRP2-elicited CTL lysis was dose-dependent. The 6 h CTL killing and spleen IFN-gamma-producing CD8(+) T cells in total CD8(+) T cells by one week's immunization with Ad hTRP2 were 94% +/- 5% and 0.87% +/- 0.12%, respectively, whereas the 6 h CTL killing and spleen IFN-gamma-producing CD8(+) T cells by Ad mTRP2 were 22% +/- 8% and 0.15% +/- 0.05% respectively. On the other hand, 80%of the mice inoculated with 1 x 10(6) B16.F10 cells a week after the immunization with Ad hTRP2 were tumor-free for three months, but companied by formation of vitiligo in the Ad injection sites. However, only 20% of the Ad mTRP2-immunized mice inoculated with 1 x 10(5) B16.F10 cells survived, and no vitiligo was formatted. CONCLUSION: Adenovirus-mediated xenogeneic melanoma-related antigen TRP2 effectively breaks immune tolerance, thus inducing strong antigen-specific cytotoxic T cell response, simultaneously companied by obvious autoimmune injury.