Bose Anamika, Chakraborty Krishnendu, Sarkar Koustav, Goswami Shyamal, Chakraborty Tathagata, Pal Smarajit, Baral Rathindranath
Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute, Kolkata, India.
J Immunother. 2009 Jan;32(1):42-53. doi: 10.1097/CJI.0b013e31818e997d.
We have demonstrated augmentation of the CD3-CD56+ natural killer (NK) and CD8+CD56_ T-cell-mediated tumor cell cytotoxicity by neem leaf glycoprotein (NLGP). These NK and T cells were isolated from the peripheral blood of head and neck squamous cell carcinoma patients with a state of immunosuppression. NLGP induces TCRalphabeta-associated cytotoxic T lymphocyte (CTL) reaction to kill oral cancer (KB) cells. This CTL reaction is assisted by NLGP-mediated up-regulation of CD28 on T cells and HLA-ABC, CD80/86 on monocytes. CTL-mediated killing of KB cells and NK-cell-mediated killing of K562 (erythroleukemic) cells are associated with activation of these cells by NLGP. This activation is evidenced by increased expression of early activation marker CD69 with altered expression of CD45RO/CD45RA. NLGP is a strong inducer of IFNgamma from both T and NK cells; however, IFNgamma regulates the T-cell-mediated cytotoxicity only without affecting NK-cell-mediated one. Reason of this differential regulation may lie within up-regulated expression of IFNgamma-receptor on T-cell surface, not on NK cells. This NLGP-induced cytotoxicity is dependent on up-regulated perforin/granzyme B expression in killer cells, which is again IFNgamma dependent in T cells and independent in NK cells. Although, FasL expression is increased by NLGP, it may not be truly linked with the cytotoxic functions, as brefeldin A could not block such NLGP-mediated cytotoxicity, like, concanamycin A, a perforin inhibitor. On the basis of these results, we conclude that NLGP might be effective to recover the suppressed cytotoxic functions of NK and T cells from head and neck squamous cell carcinoma patients.
我们已经证明，印楝叶糖蛋白（NLGP）可增强CD3-CD56+自然杀伤（NK）细胞和CD8+CD56_ T细胞介导的肿瘤细胞细胞毒性。这些NK细胞和T细胞是从处于免疫抑制状态的头颈部鳞状细胞癌患者的外周血中分离出来的。NLGP诱导与TCRalphabeta相关的细胞毒性T淋巴细胞（CTL）反应，以杀死口腔癌（KB）细胞。这种CTL反应由NLGP介导的T细胞上CD28以及单核细胞上HLA-ABC、CD80/86的上调所辅助。CTL介导的KB细胞杀伤和NK细胞介导的K562（红白血病）细胞杀伤与NLGP对这些细胞的激活有关。这种激活表现为早期激活标志物CD69表达增加，同时CD45RO/CD45RA表达改变。NLGP是T细胞和NK细胞产生IFNγ的强诱导剂；然而，IFNγ仅调节T细胞介导的细胞毒性，而不影响NK细胞介导的细胞毒性。这种差异调节的原因可能在于T细胞表面而非NK细胞表面IFNγ受体的上调表达。这种NLGP诱导的细胞毒性依赖于杀伤细胞中穿孔素/颗粒酶B表达的上调，而这在T细胞中又依赖于IFNγ，在NK细胞中则与之无关。尽管NLGP可增加FasL的表达，但它可能与细胞毒性功能并无真正关联，因为布雷菲德菌素A无法像穿孔素抑制剂 concanamycin A那样阻断这种NLGP介导的细胞毒性。基于这些结果，我们得出结论，NLGP可能有效地恢复头颈部鳞状细胞癌患者NK细胞和T细胞受抑制的细胞毒性功能。
