Hematopoietic cells expressing NP-1 induce angiogenesis in corneal neovascularization assay.

(A) Gross appearance of neovascularization in the cornea. Pellets containing control buffer (i) or a low-dose VEGF (20 ng/mL) with CD45⁺NP-1⁻ hematopoietic cells (ii) did not induce corneal neovascularization; on the other hand, pellets containing a low-dose VEGF with CD45⁺NP-1⁺hematopoietic cells (iii) or high-dose VEGF (100 ng/mL) (iv) induced corneal neovascularization. (B) Histologic analysis in mouse cornea. Sections were stained with anti–PECAM-1 (i-ii), anti–VEGFR-2 (iii-iv), or anti–VE-cadherin (v-vi) antibody, and positive cells are visualized as dark blue products. Pellets containing a low dose of VEGF and CD45⁺ cells (ii,iv,vi) induced the blood vessel formation composing with PECAM-1⁺ (ii), VEGFR-2⁺ (iv), or VE-cadherin⁺ (vi) ECs into cornea; however, pellets containing PBS alone did not (i,iii,v). Arrows indicate newly formed vessels into cornea. Scale bar indicates 50 μm.