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. Fig, 2 LH/CG-R immunodetection during in vitro trophoblast differentiation

L. Immunostaining-for and . By, K15 raised against the human 611 LH/CG receptor. LH/CG-R was expressed in both cyto-(A; 24h) and syncytotrophoblasts (B; 72h), 612 albeit more strongly in cytotrophoblasts. (E): co-immunodetection of LH/CG-R and hCG by using the 613 polyclonal antibodies LHR-H50 (C; in green) and hCG-C20 (D; in red) respectively at 48 hours of 614 culture. Single trophoblast (arrowed) was stained for LH/CG-R and aggregated trophoblasts were 615 stained for both LH/CG-R and hCG. Nuclei were labeled with DAPI (blue fluorescence)

. Fig, 3 LH/CG-R protein expression during in vitro trophoblast differentiation

. Fig, mRNA expression during in vitro trophoblast differentiation. (A): diagram 636 showing the seven transmembrane domains of the LH/CG-receptor and the location of the primers sets 637 used in this study. The two sets of primers (P1 and P2) are located on the extracellular domain, P1 638 amplifies a fragment of 647-bp in the exons 2-9 and P2 amplifies a fragment of 282-bp in the exons, pp.1-639

. Fig, 5 Scatchard analyses of 125 I-hCG binding to trophoblasts during in vitro differentiation, p.649

. Fig, 7 Immunolocalization of LH/CG-R, hCG and cytokeratin 7 in villous sections