Campbell F M, Bush P G, Veerkamp J H, Dutta-Roy A K
Rowett Research Institute, Aberdeen, Scotland, UK.
Placenta. 1998 Jul-Aug;19(5-6):409-15. doi: 10.1016/s0143-4004(98)90081-9.
The aim of this study was to investigate location and the types of membrane-associated and cytoplasmic fatty acid-binding proteins in human placental trophoblasts using monospecific polyclonal antibodies. Western blot analysis demonstrated the presence of multiple membrane and cytoplasmic fatty acid transport/binding proteins in human placenta. In addition to previously reported placental membrane fatty acid-binding (p-FABPpm, 40 kDa), fatty acid translocase (FAT, 88 kDa) and fatty acid transport protein (FATP, 62 kDa) were detected in both microvillous and basal membranes of the human placenta. Among the cytoplasmic proteins, heart (H) and liver (L) type FABP were detected in the cytosol of the human placental primary trophoblasts as well as in human placental choriocarcinoma (BeWo) cells. The immunoreactivity of epidermal type (E)-FABP was not detected in trophoblasts or BeWo cells despite its presence in human placental cytosol. Location of FAT and FATP on the both sides of the bipolar placental cells may favour transport of free fatty acids (FFA) pool in both directions i.e. from the mother to the fetus and vice versa. However, p-FABPpm, because of its exclusive location on the microvillous membranes, may favour the unidirectional flow of maternal plasma long-chain polyunsaturated fatty acids present in the FFA pool to the fetus, due to binding specificity for these fatty acids. Although the roles of these proteins in placental fatty acid uptake and metabolism are yet to be understood fully, their complex interaction may be involved in the uptake of maternal FFA by the placenta for delivery to the fetus.
本研究的目的是使用单特异性多克隆抗体研究人胎盘滋养层细胞中膜相关和细胞质脂肪酸结合蛋白的位置及类型。蛋白质印迹分析表明人胎盘中存在多种膜和细胞质脂肪酸转运/结合蛋白。除了先前报道的胎盘膜脂肪酸结合蛋白（p-FABPpm，40 kDa）外，在人胎盘的微绒毛膜和基底膜中均检测到脂肪酸转位酶（FAT，88 kDa）和脂肪酸转运蛋白（FATP，62 kDa）。在细胞质蛋白中，在人胎盘原代滋养层细胞的胞质溶胶以及人胎盘绒毛膜癌（BeWo）细胞中检测到心脏（H）型和肝脏（L）型脂肪酸结合蛋白。尽管人胎盘胞质溶胶中存在表皮型（E）-脂肪酸结合蛋白，但在滋养层细胞或BeWo细胞中未检测到其免疫反应性。FAT和FATP在双极胎盘细胞两侧的定位可能有利于游离脂肪酸（FFA）池在两个方向上的运输，即从母体到胎儿以及反之亦然。然而，p-FABPpm由于其在微绒毛膜上的独特定位，可能有利于FFA池中存在于母体血浆中的长链多不饱和脂肪酸单向流向胎儿，这是由于其对这些脂肪酸的结合特异性。尽管这些蛋白在胎盘脂肪酸摄取和代谢中的作用尚未完全明了，但它们之间复杂的相互作用可能参与胎盘对母体FFA的摄取以便传递给胎儿。
