Figure 2.

Increased decidual vascular complement deposition before placentation in BPH/5 pregnancies. A–C) qRT-PCR analysis of C1qa, C3, and CfB mRNA expression in C57 and BPH/5 implantation sites at E7.5. A) C1qa mRNA expression was unchanged. B) C3 mRNA expression was increased in BPH/5 pregnancies. **P = 0.004. C) CfB mRNA expression was increased in BPH/5 pregnancies. *P = 0.05. D–F) IF staining was performed on tissue sections of implantation sites at E7.5. Nuclei were stained with DAPI (blue). White boxes: areas magnified in the insets. Scale bars, 500 µm. C3 deposition was detected in the ectoplacental cone (area between the dashed yellow line and embryo) and around the decidual vasculature (arrowheads) of the C57 (D) and BPH/5 (E) implantation sites. Anti-goat secondary antibody alone (F) was used for C3 controls. G–J) Double staining IF was performed for CD31 and C3. Representative areas of the decidual vasculature are shown. Scale bars, 100 µm. CD31 identifies decidual vessels (G, I) C3 deposition around the vasculature was increased in BPH/5 pregnancies (J) as compared to C57 controls (H). To quantitatively assess the relative amount of C3 deposition in BPH/5 and C57 implantation sites, we calculated and compared CTCF. K) CTCF for C3 was significantly higher in BPH/5 pregnancies as compared to C57 controls. **P = 0.002. Results represent the median and IQR (n = 5–12 implantation sites/group). am, antimesometrial; e, embryo; m, mesometrial; v, vessels.