Figure 6.

Analysis of Cxcr7-null phenotype and CXCR7 protein expression

(A–E) Wild-type (A and C) and Cxcr7^−/− SLVs (B, D, and E) immunostained with anti-PECAM-1 antibodies. Arrows in (D) and (E) indicate edges of leaflet bases; misalignment of the left (L) and right (R) leaflets was observed in (E), but not (D).

(F) Graphs show mean SLV section area in E15.5 controls, Cxcl12^−/−, and Cxcr7^−/− SLVs. Individual values are shown; bars indicate mean ± SD; ^∗∗p < 0.01 and ^∗∗∗p < 0.001 (unpaired Student’s t test).

(G) Analysis of CXCR4⁺ MC orientation in Cxcr7-null and control E11.5 OFT. Graphs compare cell percentages per orientation, standard deviation in brackets; table shows cell numbers. Inset circular diagram indicates criteria for cell orientation. No significant difference between controls and nulls is shown (p = 0.636; chi-squared test).

(H) Distribution of CXCR4⁺ MCs in distal, proximal, and medial OFT as a percentage of total CXCR4⁺ MC number, in wild type (n = 4) and Cxcr7^-/- (n = 5). Error bars represent ±SD; ns, non-significant, ∗p ≤ 0.05 (Student’s t test).

(I–M’’) Detection of CXCR7 in HA-CXCR7 mice: distal (I–J”), medial (K–K”), and proximal (L–L”) E11.5 OFT and E12.5 AoV sections (M–M”) were co-immunostained with anti-HA (detecting CXCR7), CXCR4 (cl. 2B11; detecting total CXCR4), and anti-PECAM-1 antibodies. Boxed regions in (I)–(I”) are enlarged in neighboring (J)–(J”). Arrows in (K)–(K”) indicate CXCR4⁺ MCs.

Scale bars represent 100 μm. See also Figure S5.