Department of Medical Biology, Medical School, Pecs, Hungary; MTA - PTE Human Reproduction Research Group, Hungary; János Szentágothai Research Centre, University of Pecs, Hungary; Endocrine Studies, Centre of Excellence, Hungary.
Institute for Medical Research and Education, Essen, Germany.
Best Pract Res Clin Obstet Gynaecol. 2019 Oct;60:17-23. doi: 10.1016/j.bpobgyn.2019.07.001. Epub 2019 Jul 5.
Fifty percent of fetal antigens are of paternal origin. These are recognized by the maternal immune system, thereby resulting in lymphocyte activation and the induction of progesterone receptors (PRs) in immune cells. Upon binding of progesterone to PRs on lymphocytes, a downstream mediator called progesterone-induced blocking factor (PIBF) is produced. The full-length PIBF is a 90 kDa protein; however, because of alternative splicing, several smaller isoforms are also produced. While the 90 kDa molecule plays a role in cell cycle regulation, the small isoforms are localized in the cytoplasm, and after secretion, they bind to their receptors on other cells and act in a cytokine-like manner. The communication between the embryo and the maternal immune system is established through PIBF-containing extracellular vesicles. PIBF induces an increased production of Th2 cytokines and inhibits degranulation of NK cells, and by regulating the maternal immune response, it contributes to successful implantation and maintenance of pregnancy.
胎儿抗原有 50%来自父系。这些抗原被母体免疫系统识别，从而导致淋巴细胞活化，并在免疫细胞中诱导孕激素受体（PR）。孕激素与淋巴细胞上的 PR 结合后，会产生一种称为孕激素诱导阻断因子（PIBF）的下游介质。全长 PIBF 是一种 90 kDa 的蛋白质；然而，由于选择性剪接，也会产生几种较小的同种型。虽然 90 kDa 分子在细胞周期调节中发挥作用，但小同种型定位于细胞质中，分泌后，它们与其他细胞上的受体结合，并以细胞因子样方式发挥作用。胚胎和母体免疫系统之间的通讯是通过含有 PIBF 的细胞外囊泡建立的。PIBF 诱导 Th2 细胞因子的产生增加，并抑制 NK 细胞脱颗粒，通过调节母体免疫反应，它有助于成功着床和妊娠的维持。
