Santin A D, Hermonat P L, Ravaggi A, Chiriva-Internati M, Zhan D, Pecorelli S, Parham G P, Cannon M J
Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Arkansas, Little Rock, Arkansas, USA.
J Virol. 1999 Jul;73(7):5402-10. doi: 10.1128/JVI.73.7.5402-5410.1999.
Human papillomavirus (HPV) type 16 (HPV 16) and HPV type 18 (HPV 18) are implicated in the induction and progression of the majority of cervical cancers. Since the E6 and E7 oncoproteins of these viruses are expressed in these lesions, such proteins might be potential tumor-specific targets for immunotherapy. In this report, we demonstrate that recombinant, full-length E7-pulsed autologous dendritic cells (DC) can elicit a specific CD8(+) cytotoxic T-lymphocyte (CTL) response against autologous tumor target cells in three patients with HPV 16- or HPV 18-positive cervical cancer. E7-specific CTL populations expressed strong cytolytic activity against autologous tumor cells, did not lyse autologous concanavalin A-treated lymphoblasts or autologous Epstein-Barr virus-transformed lymphoblastoid cell lines (LCL), and showed low levels of cytotoxicity against natural killer cell-sensitive K562 cells. Cytotoxicity against autologous tumor cells could be significantly blocked by anti-HLA class I (W6/32) and anti-CD11a/LFA-1 antibodies. Phenotypically, all CTL populations were CD3(+)/CD8(+), with variable levels of CD56 expression. CTL induced by E7-pulsed DC were also highly cytotoxic against an allogeneic HLA-A2(+) HPV 16-positive matched cell line (CaSki). In addition, we show that specific lymphoproliferative responses by autologous CD4(+) T cells can also be induced by E7-pulsed autologus DC. E7-specific CD4(+) T cells proliferated in response to E7-pulsed LCL but not unpulsed LCL, and this response could be blocked by anti-HLA class II antibody. Finally, with two-color flow cytometric analysis of intracellular cytokine expression at the single-cell level, a marked Th1-like bias (as determined by the frequency of gamma interferon- and interleukin 4-expressing cells) was observable for both CD8(+) and CD4(+) E7-specific lymphocyte populations. Taken together, these data demonstrate that full-length E7-pulsed DC can induce both E7-specific CD4(+) T-cell proliferative responses and strong CD8(+) CTL responses capable of lysing autologous naturally HPV-infected cancer cells in patients with cervical cancer. These results may have important implications for the treatment of cervical cancer patients with active or adoptive immunotherapy.
人乳头瘤病毒16型（HPV 16）和人乳头瘤病毒18型（HPV 18）与大多数宫颈癌的发生和发展有关。由于这些病毒的E6和E7癌蛋白在这些病变中表达，因此这类蛋白可能是免疫治疗潜在的肿瘤特异性靶点。在本报告中，我们证明重组的全长E7脉冲自体树突状细胞（DC）可在3例HPV 16或HPV 18阳性宫颈癌患者中引发针对自体肿瘤靶细胞的特异性CD8(+)细胞毒性T淋巴细胞（CTL）反应。E7特异性CTL群体对自体肿瘤细胞表现出强大的溶细胞活性，不裂解自体伴刀豆球蛋白A处理的淋巴母细胞或自体爱泼斯坦-巴尔病毒转化的淋巴母细胞系（LCL），并且对自然杀伤细胞敏感的K562细胞表现出低水平的细胞毒性。针对自体肿瘤细胞的细胞毒性可被抗HLA I类（W6/32）和抗CD11a/LFA-1抗体显著阻断。从表型上看，所有CTL群体均为CD3(+)/CD8(+)，CD56表达水平各异。由E7脉冲DC诱导的CTL对同种异体HLA-A2(+) HPV 16阳性匹配细胞系（CaSki）也具有高度细胞毒性。此外，我们表明E7脉冲自体DC也可诱导自体CD4(+) T细胞产生特异性淋巴细胞增殖反应。E7特异性CD4(+) T细胞对E7脉冲LCL有增殖反应，但对未脉冲的LCL无反应，且该反应可被抗HLA II类抗体阻断。最后，通过单细胞水平的细胞内细胞因子表达的双色流式细胞术分析，在CD8(+)和CD4(+) E7特异性淋巴细胞群体中均观察到明显的Th1样偏向（由表达γ干扰素和白细胞介素4的细胞频率确定）。综上所述，这些数据表明全长E7脉冲DC可诱导E7特异性CD4(+) T细胞增殖反应以及强大的CD8(+) CTL反应，后者能够裂解宫颈癌患者中自体天然HPV感染的癌细胞。这些结果可能对采用主动或过继免疫疗法治疗宫颈癌患者具有重要意义。
