Federal State Budgetary Scientific Institution, Research Institute of Obstetrics, Gynecology, and Reproductology Named after D.O. Ott, Russia.
Federal State Budgetary Scientific Institution, Research Institute of Experimental Medicine, Russia.
Immunobiology. 2020 May;225(3):151910. doi: 10.1016/j.imbio.2020.151910. Epub 2020 Feb 1.
Natural killer (NK) cells are the main population of leukocytes in decidua during the first trimester of pregnancy. NK cells can have contact with trophoblast cells during pregnancy, which raises the possibility of mutual influence. This research aimed to evaluate the proliferation and phenotype of peripheral blood NK cells in the presence of trophoblast cells of the JEG-3 cell line. We showed that trophoblast cells of the JEG-3 cell line (American Type Culture Collection (ATCC), USA) produced TGFβ. However, co-culturing of NK and trophoblast cells did not change the SMAD2/3 to pSMAD2/3 ratio within NK cells. These data indicate that the canonical signaling pathway from TGFβ is not activated, but do not preclude activation of SMAD-independent signaling pathways through the effect of TGFβ and/or other cytokines. We established that trophoblast cells inhibited both constitutive and IL-2-induced expression of Ki-67 proliferation marker by NK cells in vitro in both pregnant and non-pregnant women. Constitutive and induced Ki-67 expression by peripheral blood NK cells was increased in pregnant women compared with non-pregnant women. The influence of trophoblast cells on Ki-67 expression by NK cells was more pronounced in the presence of other mononuclear cells than in their absence. In the presence of trophoblast cells and IL-2, the number of NK cells with the CD16+CD57- phenotype in peripheral blood mononuclear cells (PBMCs) was increased in pregnant and non-pregnant women, compared with culturing with IL-2 only. This might reflect a decrease in the number of NK cells at the terminal stage of differentiation. We also revealed the increased content of NK cells with the CD16-CD56bright phenotype in PBMCs of pregnant women when incubated with trophoblast cells and IL-2, compared with culturing with trophoblast cells only. Our results suggest that NK cells need contact interactions with trophoblast cells and additional cytokine stimulation (IL-2, cytokines of other mononuclear cells) to acquire the CD56bright phenotype.
自然杀伤 (NK) 细胞是妊娠早期蜕膜中白细胞的主要群体。NK 细胞在怀孕期间可以与滋养层细胞接触，这增加了相互影响的可能性。本研究旨在评估 JEG-3 细胞系滋养层细胞存在的情况下外周血 NK 细胞的增殖和表型。我们表明，JEG-3 细胞系（美国典型培养物保藏中心，美国）的滋养层细胞产生 TGFβ。然而，NK 和滋养层细胞的共培养并未改变 NK 细胞内 SMAD2/3 向 pSMAD2/3 的比值。这些数据表明，TGFβ 的经典信号通路未被激活，但不能排除 TGFβ 和/或其他细胞因子的作用激活非 SMAD 依赖性信号通路。我们确定，滋养层细胞在体外抑制 NK 细胞的 Ki-67 增殖标志物的组成型和 IL-2 诱导表达，无论是在孕妇还是非孕妇中。与非孕妇相比，孕妇外周血 NK 细胞的组成型和诱导型 Ki-67 表达增加。与不存在其他单核细胞相比，滋养层细胞对 NK 细胞 Ki-67 表达的影响在存在其他单核细胞时更为明显。在存在滋养层细胞和 IL-2 的情况下，与仅培养 IL-2 相比，孕妇和非孕妇外周血单个核细胞（PBMC）中具有 CD16+CD57-表型的 NK 细胞数量增加。这可能反映了 NK 细胞在终末分化阶段数量的减少。我们还发现，与仅培养滋养层细胞相比，在培养滋养层细胞和 IL-2 时，孕妇 PBMC 中具有 CD16-CD56bright 表型的 NK 细胞含量增加。我们的结果表明，NK 细胞需要与滋养层细胞接触，并接受额外的细胞因子刺激（IL-2、其他单核细胞的细胞因子）才能获得 CD56bright 表型。
