Bone marrow cells recruited through the neuropilin-1 receptor promote arterial formation at the sites of adult neoangiogenesis in mice
J. Clin. Invest. Serena Zacchigna, et al. 118:2062 doi:10.1172/JCI32832 [Go to this article.]

Figure 3
Recruitment of NP-1⁺ myeloid cells by VEGF₁₆₅ and Sema3A. (A) The intramuscular injection of AAV-VEGF₁₆₅ or AAV-Sema3A in female mice transplanted with male BM determined a massive infiltration of Y chromosome–positive cells (shown by FISH as a green dot inside a DAPI-stained blue nucleus). Scale bar: 100 μm. (B) The vast majority (>80%) of the cells recruited by both VEGF₁₆₅ and Sema3A scored positive for the panleukocytic marker CD45 (left) as well as for the monocyte marker CD11b (right). Scale bar: 100 μm. (C) The cellular infiltrates from the muscles expressing either VEGF₁₆₅ or Sema3A were laser microdissected to determine the expression levels of Flk-1, Flt-1, NP-1, and NP-2 by real-time PCR (normalized to those of the housekeeping gene GAPDH). With the exception of NP-2, these receptors were abundantly expressed in VEGF₁₆₅-expressing muscles (white bars). In contrast, in muscles injected with AAV-Sema3A, NP-1 was the most abundantly expressed receptor (black bars). Shown are means ± SD of 3 independent quantifications. (D) The same quantifications described in C were performed on primary CD11b⁺ cells purified from the BM. Shown are means ± SD of 3 independent quantifications. (E) The majority of the cells recruited by both VEGF₁₆₅ and Sema3A were colabeled by antibodies against CD11b (green) and NP-1 (red). NP-1 expression was also detected in the microvasculature (25). Scale bar: 100 μm. (F) Infiltrating CD11b⁺ cells from VEGF₁₆₅- and Sema3A-transduced muscles were stained with antibodies against CD11b⁺ (red) and NP-2 (green). The majority of cells scored negative for NP-2, which was expressed by some vessels.