Yahata G, Ueda H, Takakuwa K, Kodama S, Tanaka K, Kanazawa K
Department of Obstetrics and Gynecology, Niigata University School of Medicine, Japan.
Cell Growth Differ. 1990 Feb;1(2):73-8.
Research on the escape mechanism of the fetoplacental unit has focused on the placental trophoblast, which is though to play an important role in the survival of the fetus. There are two major findings in the present study: (a) The expression of human leukocyte antigen (HLA)-A, -B, and -C locus specific genes is greatly reduced in trophoblast cells compared to embryonic cells by Northern blot analysis using locus specific oligonucleotide probes. This is true even though the transcripts detected by a complementary DNA probe, which contains a very conserved sequence present in all members of the HLA gene family, are equally abundant in trophoblast and embryonic cells. (b) When trophoblast cells or embryonic cells are cocultured with peripheral blood lymphocytes from the corresponding female in the presence of recombinant interleukin 2, allogeneic cytotoxic T lymphocytes are generated only in cultures with embryonic cells, and trophoblast cells express the resistance to lysis by the allogeneic cytotoxic T lymphocytes. These results strongly suggest that the reduction in expression of transplantation antigens (HLA-A, -B, and -C) might address the question why maternal tissue does not reject trophoblast cells.
胎盘胎儿单位逃逸机制的研究主要集中在胎盘滋养层细胞，一般认为其在胎儿存活中发挥重要作用。本研究有两项主要发现：（a）运用位点特异性寡核苷酸探针进行Northern印迹分析发现，与胚胎细胞相比，滋养层细胞中人白细胞抗原（HLA）-A、-B和-C位点特异性基因的表达显著降低。即便使用包含HLA基因家族所有成员中均存在的高度保守序列的互补DNA探针检测到的转录本在滋养层细胞和胚胎细胞中同样丰富，上述情况依然存在。（b）当滋养层细胞或胚胎细胞在重组白细胞介素2存在的情况下与相应女性的外周血淋巴细胞共培养时，仅在含有胚胎细胞的培养物中产生同种异体细胞毒性T淋巴细胞，而滋养层细胞对同种异体细胞毒性T淋巴细胞的裂解具有抗性。这些结果有力地表明，移植抗原（HLA-A、-B和-C）表达的降低或许可以解释为何母体组织不会排斥滋养层细胞这一问题。
