Laboratory for Biology of Reproduction, Institute INEP, University of Belgrade, Belgrade, Serbia.
PLoS One. 2011;6(12):e28514. doi: 10.1371/journal.pone.0028514. Epub 2011 Dec 8.
Interactions of glycoconjugates with endogenous galectins, have been long proposed to participate in several reproductive processes including implantation. In human placenta gal-1, gal-3, gal-8, and gal-13 proteins are known to be present. Each of them has been proposed to play multiple functions, but so far no clear picture has emerged. We hypothesized that gal-1 participates in trophoblast invasion, and conducted Matrigel invasion assay using isolated cytotrophoblast from first trimester placenta and HTR-8/SVneo cell line to test it.
Function blocking anti-gal-1 antibody was employed to assess participation of endogenous gal-1 in cell adhesion, cell invasion of HTR-8/SVneo cells. When gal-1 was blocked in isolated trophoblast cell invasion was reduced to 75% of control (SEM ± 6.3, P<0.001) and to 66% of control (SEM ± 1.7, P<0.001) in HTR-8/SVneo cell line. Increased availability of gal-1, as two molecular forms of recombinant human gal-1 (CS-gal-1 and Ox-gal-1), resulted in increased cell invasion by cytotrophoblast to 151% (SEM ± 16, P<0.01) with 1 ng/ml of CS-gal-1, and to 192% (SEM ± 51, P<0.05) with 1 µg/ml of Ox-gal-1. Stimulation was also observed in HTR-8/SVneo cells, to 317% (SEM ± 58, P<0.001) by CS-gal-1, and to 200% (SEM ± 24, P<0.001) by Ox-gal-1 at 1 µg/ml. Both sets of results confirmed involvement of gal-1 in trophoblast invasion. Galectin profile of isolated cytotrophoblast and HTR-8/SVneo cells was established using RT-PCR and real-time PCR and found to consist of gal-1, gal-3 and gal-8 for both cell types. Only gal-1 was located at the trophoblast cell membrane, as determined by FACS analysis, which is consistent with the results of the functional tests.
These findings qualify gal-1 as a member of human trophoblast cell invasion machinery.
糖缀合物与内源性半乳糖凝集素的相互作用，长期以来一直被认为参与了包括着床在内的几种生殖过程。在人胎盘组织中，已知存在 gal-1、gal-3、gal-8 和 gal-13 蛋白。它们中的每一种都被认为具有多种功能，但到目前为止，还没有一个清晰的画面出现。我们假设 gal-1 参与滋养层细胞的侵袭，并使用从第一孕期胎盘分离的细胞滋养层和 HTR-8/SVneo 细胞系进行 Matrigel 侵袭实验来验证这一假设。
采用功能阻断抗 gal-1 抗体来评估内源性 gal-1 在细胞黏附、HTR-8/SVneo 细胞侵袭中的作用。当阻断 gal-1 时，细胞滋养层的侵袭减少到对照组的 75%（SEM ± 6.3，P<0.001）和 HTR-8/SVneo 细胞系的 66%（SEM ± 1.7，P<0.001）。两种重组人 gal-1（CS-gal-1 和 Ox-gal-1）的形式增加了 gal-1 的可用性，导致细胞滋养层的细胞侵袭增加到 151%（SEM ± 16，P<0.01），用 1ng/ml 的 CS-gal-1，和 192%（SEM ± 51，P<0.05），用 1μg/ml 的 Ox-gal-1。在 HTR-8/SVneo 细胞中也观察到刺激作用，CS-gal-1 刺激作用为 317%（SEM ± 58，P<0.001），Ox-gal-1 刺激作用为 200%（SEM ± 24，P<0.001），用 1μg/ml。这两组结果都证实了 gal-1 参与了滋养层细胞的侵袭。使用 RT-PCR 和实时 PCR 建立了分离的细胞滋养层和 HTR-8/SVneo 细胞的半乳糖凝集素谱，并发现两种细胞类型均含有 gal-1、gal-3 和 gal-8。通过 FACS 分析发现，只有 gal-1 定位于滋养层细胞膜上，这与功能测试的结果一致。
这些发现将 gal-1 确定为人类滋养层细胞侵袭机制的成员。
