Albini Adriana, Gallazzi Matteo, Palano Maria Teresa, Carlini Valentina, Ricotta Riccardo, Bruno Antonino, Stetler-Stevenson William G, Noonan Douglas M
Laboratory of Vascular Biology and Angiogenesis, IRCCS MultiMedica, 20138 Milan, Italy.
Immunology and General Pathology Laboratory, Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy.
Cancers (Basel). 2021 Oct 1;13(19):4955. doi: 10.3390/cancers13194955.
Natural Killer (NK) cells have been found to be anergic, exhausted and pro-angiogenic in cancers. NK cell from healthy donors, exposed to TGFβ, acquire the CD56CD9CD49a decidual-like-phenotype, together with decreased levels of NKG2D activation marker, increased levels of TIM-3 exhaustion marker, similar to cancer-associated NK cells. Tissue inhibitors of metalloproteases (TIMPs) exert dual roles in cancer. The role of TIMPs in modulating immune cells is a very novel concept, and the present is the first report studying their ability to contrast TGFβ action on NK cells. Here, we investigated the effects of TIMP1 and TIMP2 recombinant proteins in hindering decidual-like markers in NK cells, generated by polarizing cytolytic NK cells with TGFβ. The effects of TIMP1 or TIMP2 on NK cell surface antigens were determined by multicolor flow cytometry. We found that TIMP1 and TIMP2 were effective in interfering with TGFβ induced NK cell polarization towards a decidual-like-phenotype. TIMP1 and TIMP2 counteracted the effect of TGFβ in increasing the percentage of CD56 CD16, CD9 and CD49a, and restoring normal levels for TIMP 1 and 2 also inhibited decrease levels of the activation marker NKG2D induced by TGFβ and decreased the TGFβ upregulated exhaustion marker TIM-3. NK cell degranulation capabilities against K562 cells were also decreased by TGFβ and not by TIMP1 or TIMP2. TIMP1 treatment could partially restore degranulation marker CD107a expression. Treatment with recombinant TIMP-1 or TIMP-2 showed a trend, although not statistically significant, to decrease CD49a and TIM-3+ expression and increase NKG2D in peripheral blood NK cells exposed to conditioned media from colon cancer cell lines. Our results suggest a potential role of TIMPs in controlling the tumor-associated cytokine TGFβ-induced NK cell polarization. Given the heterogeneity of released factors within the TME, it is clear that TGFβ stimulation represents a model to prove TIMP's new properties, but it cannot be envisaged as a soloist NK cell polarizing agent. Therefore, further studies from the scientific community will help defining TIMPs immunomodulatory activities of NK cells in cancer, and their possible future diagnostic-therapeutic roles.
自然杀伤（NK）细胞在癌症中被发现具有无反应性、耗竭性和促血管生成性。来自健康供体的NK细胞在接触转化生长因子β（TGFβ）后，会获得CD56CD9CD49a蜕膜样表型，同时NKG2D激活标志物水平降低，T细胞免疫球蛋白黏蛋白分子3（TIM-3）耗竭标志物水平升高，这与癌症相关NK细胞相似。金属蛋白酶组织抑制剂（TIMPs）在癌症中发挥双重作用。TIMPs在调节免疫细胞方面的作用是一个非常新颖的概念，本文是第一项研究其对抗TGFβ对NK细胞作用能力的报告。在这里，我们研究了TIMP1和TIMP2重组蛋白在阻碍NK细胞中蜕膜样标志物形成方面的作用，这些标志物是通过用TGFβ极化细胞毒性NK细胞产生的。通过多色流式细胞术确定TIMP1或TIMP2对NK细胞表面抗原的影响。我们发现TIMP1和TIMP2能有效干扰TGFβ诱导的NK细胞向蜕膜样表型的极化。TIMP1和TIMP2抵消了TGFβ增加CD56 CD16、CD9和CD49a百分比的作用，并使TIMP 1和2恢复到正常水平，同时也抑制了TGFβ诱导的激活标志物NKG2D水平的降低，并降低了TGFβ上调的耗竭标志物TIM-3。TGFβ也会降低NK细胞对K562细胞的脱颗粒能力，但TIMP1或TIMP2不会。TIMP1处理可部分恢复脱颗粒标志物CD107a的表达。在用来自结肠癌细胞系的条件培养基处理的外周血NK细胞中，重组TIMP-1或TIMP-2处理呈现出降低CD49a和TIM-3+表达并增加NKG2D的趋势，尽管在统计学上不显著。我们的结果表明TIMPs在控制肿瘤相关细胞因子TGFβ诱导的NK细胞极化方面具有潜在作用。鉴于肿瘤微环境中释放因子的异质性，很明显TGFβ刺激是证明TIMP新特性的一个模型，但不能将其设想为单独的NK细胞极化剂。因此，科学界的进一步研究将有助于明确TIMPs在癌症中对NK细胞的免疫调节活性及其未来可能的诊断治疗作用。
