Figure 1. LV density and VEGF-C/VEGFR3 signaling are increased in the colon of IBD patients.

(A and B) Immunohistochemical staining with an Ab recognizing podoplanin was performed on control (NL) and active CD– and UC–involved colons (A). Quantitative analysis of LV density in the same sections is shown in B. Data are expressed as the mean percentage of LV per area ± SEM. Scale bar: 100 μm. (C) Control (n = 15) and CD (n = 16) and UC (n = 16) patients with active inflammation were investigated for VEGF-C and VEGF-D content in mucosal extracts. VEGF-C and VEGF-D were measured by ELISA. (D) Frozen sections from the colons of control (NL, n = 15) or CD (IBD, n = 16) patients with active inflammation stained with both anti-LYVE1 and anti-VEGFR3 Abs. Original magnification, ×40. (E) VEGFR3⁺ LVs were quantified by stereological point counting of 10 regions per section, and the numbers were normalized per total section area expressed in mm². Results are presented as the mean vessel density per group ± SEM. (F and G) MFI per vessel was analyzed on VEGFR3⁺ (F) and LYVE1⁺ (G) LVs (10–15 vessels per section). MFI is expressed as relative units normalized per vascular area expressed in μm². *P < 0.01; **P < 0.001 (B, C, E, and F).