Figure 3: Loss of IRSp53 affects placental morphology and function.

(A) Morphology of wildtype, heterozygous and null placentas at E14.5. Haemorrhages were observed in the IRSp53 KO. (B) Labyrinth vasculature revealed by immunostaining for CD31 in E14.5 placentas. Right panels show boxed areas at higher magnification. Scale: 100 μm. (C) Number of CD31⁺ vessels per unit area in E14.5 placentas. Three placentas were analysed for each genotype. Error bars = s.d. ****p < 0.0001, two-tailed t-test. (D) Lumen size of CD31⁺ blood vessels in E14.5 placentas. Whiskers mark maximum and minimum values. Three placentas were analysed for each genotype. ***p < 0.001, ****p < 0.0001, two-tailed t-test. (E) In vitro microvessel formation from E14.5 umbilical arterial explants examined by staining explants cultured for 3 days in collagen I gels with Hoeschst and CD31 antibodies. (F) Expression of lineage marker genes in E14.5 placentas measured by qRT-PCR. Values normalized to Tbp, plotted relative to WT. Error bars = s.d. of 4 independent sets of placentas, *p < 0.05, paired t-test. (G) In situ hybridization of Tpbpa transcripts to examine the spongiotrophoblast layer of E14.5 placentas. st, spongiotrophoblast layer; lb, labyrinth layer.