Zuckermann F A, Head J R
J Immunol. 1986 Aug 1;137(3):846-53.
Primary cultures of defined populations of mouse trophoblast, isolated from mature placentas, were analyzed for their MHC antigen expression and for the modulatory effect of interferon (IFN) by antibody- and complement-mediated cytotoxicity and flow cytofluorometry. The cells were obtained from placentas by enzymatic digestion, followed by Percoll gradient fractionation, and are large, fetally derived epithelial cells, which we previously characterized and identified as trophoblast cells. After 2 days in culture, a significant proportion of the trophoblast cells were susceptible to antibody- and complement-mediated lysis by anti-paternal strain alloantisera (40%) and, to a lesser degree, by an anti-class I monoclonal antibody (20%). Flow cytofluorometric analysis indicated that 20 to 50% of the cultured trophoblast cells expressed low levels of paternal strain class I antigens as compared to L cell fibroblasts. After culture for 48 hr with IFN-alpha/beta or IFN-gamma, the percent of class I-positive cells was increased to 68 to 76%, as was the mean fluorescence intensity, which correlated with the increased percent of antibody- and complement-mediated specific lysis (73%). No expression of class II MHC antigen by the cultured trophoblast cells was detected, even after culture in the presence of IFN-gamma. The cultured trophoblast cells, when tested for alkaline phosphatase (AP) activity, were composed of strongly positive and weakly positive subpopulations. An inverse correlation between strength of AP activity and the expression of H-2 was observed by double staining. These results indicate that trophoblast cells cultured in vitro are able to express paternal strain class I but not class II MHC antigens, as has been reported in vivo, and that this expression can be modulated by IFN. Further study of these cells should provide important clues for the understanding of materno-fetal coexistence in the face of MHC antigen differences.
从成熟胎盘分离出特定群体的小鼠滋养层细胞进行原代培养，通过抗体和补体介导的细胞毒性以及流式细胞荧光术分析其MHC抗原表达和干扰素（IFN）的调节作用。细胞通过酶消化从胎盘获得，随后进行Percoll梯度分级分离，是大型的、源自胎儿的上皮细胞，我们之前已对其进行表征并鉴定为滋养层细胞。培养2天后，相当一部分滋养层细胞易被抗父本菌株同种抗血清（40%）以及程度较轻地被抗I类单克隆抗体（20%）介导的抗体和补体溶解。流式细胞荧光术分析表明，与L细胞成纤维细胞相比，20%至50%的培养滋养层细胞表达低水平的父本菌株I类抗原。用IFN-α/β或IFN-γ培养48小时后，I类阳性细胞百分比增加到68%至76%，平均荧光强度也增加，这与抗体和补体介导的特异性溶解百分比增加（73%）相关。即使在IFN-γ存在下培养，也未检测到培养的滋养层细胞表达II类MHC抗原。对培养的滋养层细胞进行碱性磷酸酶（AP）活性检测时，其由强阳性和弱阳性亚群组成。通过双重染色观察到AP活性强度与H-2表达之间呈负相关。这些结果表明体外培养的滋养层细胞能够表达父本菌株I类而非II类MHC抗原，正如体内所报道的那样，并且这种表达可被IFN调节。对这些细胞的进一步研究应为理解面对MHC抗原差异时母胎共存提供重要线索。
