Hannan Natalie J, Salamonsen Lois A
Prince Henry's Institute of Medical Research, Clayton, 3168 Victoria, Australia.
Biol Reprod. 2008 Jul;79(1):58-65. doi: 10.1095/biolreprod.107.066480. Epub 2008 Mar 26.
Embryo implantation is a complex process involving blastocyst attachment to the endometrial epithelium and subsequent trophoblast invasion of the decidua. We have previously shown that the chemokines CX3CL1 and CCL14 are abundant in endometrial vasculature, epithelial, and decidual cells at this time, and that their receptors, CX3CR1 and CCR1, are present on invading human trophoblasts. CX3CL1 and CCL14 promote trophoblast migration. We hypothesized that these endometrial chemokines promote trophoblast migration by regulating adhesion molecules and extracellular matrix (ECM) components on the trophoblast, similar to mechanisms used in leukocyte trafficking. Trophoblast cells (AC1M-88) used previously showed a marked increase in adhesion to fibronectin following treatment with CX3CL1 and CCL14. Alterations in trophoblast adhesion and ECM following chemokine stimulation were examined using pathway-specific oligo-arrays and quantitative real-time RT-PCR. More than 30 genes were affected by CX3CL1 treatment, and 15 genes were found to be regulated by CCL14 treatment. Real-time RT-PCR quantitation revealed significant changes in the mRNA transcripts of alpha-catenin (CTNNA1), extracellular matrix protein 1 (ECM1), osteopontin (SPP1), integrin alpha 6 (ITGA6), matrix metalloproteinase 12 (MMP12), and integrin beta 5 (ITGB5) following chemokine treatment. Several of these genes have previously been implicated in implantation. Immunohistochemistry confirmed the presence of integrin alpha 6 and SPP1 protein in first-trimester human implantation sites. The temporal and spatial expression of chemokines, their receptors, adhesion, and ECM at the maternal-fetal interface emphasizes an important role in the controlled directional migration of trophoblasts through the maternal decidua. For the first time, this study demonstrates the direct effects of CX3CL1 and CCL14 on trophoblast adhesion molecules and ECM, suggesting mechanisms by which trophoblast cells migrate during early pregnancy.
胚胎着床是一个复杂的过程，涉及囊胚附着于子宫内膜上皮以及随后滋养层对蜕膜的侵袭。我们之前已经表明，趋化因子CX3CL1和CCL14此时在子宫内膜血管、上皮和蜕膜细胞中大量存在，并且它们的受体CX3CR1和CCR1存在于侵袭性人滋养层细胞上。CX3CL1和CCL14促进滋养层细胞迁移。我们推测这些子宫内膜趋化因子通过调节滋养层细胞上的黏附分子和细胞外基质（ECM）成分来促进滋养层细胞迁移，类似于白细胞迁移所采用的机制。之前使用的滋养层细胞（AC1M - 88）在用CX3CL1和CCL14处理后，对纤连蛋白的黏附显著增加。使用通路特异性寡核苷酸阵列和定量实时逆转录聚合酶链反应（RT - PCR）检测趋化因子刺激后滋养层细胞黏附及细胞外基质的变化。超过30个基因受CX3CL1处理影响，15个基因被发现受CCL14处理调控。实时RT - PCR定量显示，趋化因子处理后，α - 连环蛋白（CTNNA1）、细胞外基质蛋白1（ECM1）、骨桥蛋白（SPP1）、整合素α6（ITGA6）、基质金属蛋白酶12（MMP12）和整合素β5（ITGB5）的mRNA转录本有显著变化。这些基因中有几个之前已被证明与着床有关。免疫组织化学证实了整合素α6和SPP1蛋白在孕早期人着床部位的存在。趋化因子、其受体、黏附分子和细胞外基质在母胎界面的时空表达强调了它们在控制滋养层细胞通过母体蜕膜进行定向迁移中的重要作用。本研究首次证明了CX3CL1和CCL14对滋养层黏附分子和细胞外基质的直接作用，提示了妊娠早期滋养层细胞迁移的机制。
