Fig. 1.

Expression of IL-1R1 in different human trophoblast subtypes. (A) Expression of IL-1R1 mRNA in 6 different primary EVT and 5 different vCTB cell pools measured by gene chip analyses. Markers of EVT differentiation integrin α5 (ITGA5) and HLA-G1 were elevated in isolated EVT cell pools whereas the vCTB-associated gene integrin α6 (ITGA6) was decreased. (B) IL-1R1 immunofluorescence in first trimester placental tissue (6th week), decidua basalis (11th week) and in first trimester primary EVT (n = 3) cultured for 24 and 48 h on fibronectin. Pan-keratin (KRT) antibodies were used to depict trophoblasts in placental and decidual tissue sections. Four different first trimester placentae, and three different decidua basalis regions were analysed. Representative pictures at a 200 fold (tissue sections) and 400 fold (primary EVT) magnification are shown. Areas of villous stroma (VS), cell column (CC), extravillous trophoblast (EVT) and villous cytotrophoblast (vCTB) are indicated. KRT-positive EVT expressing IL-1R1 in decidual tissue are marked by *. Integrin α1 (ITGA1) was used to monitor matrix-dependent differentiation of primary EVT. (C) Western blot analyses of IL-1R1 in primary EVT cultivated for 24 and 48 h on fibronectin. GAPDH was used as a loading control. A representative example is shown. IL-1R1 signals were normalised to GAPDH protein expression using densitometrical scanning. Bar graphs represent mean values ± S.D. of three different experiments, * indicates p < 0.05.