NRP1 and neoplasm: Sema3A regulates intratumoral M1-Mφs (CD11b+Ly6G-Ly6ClowMHCIIhigh) and M2-Mφs (CD11b+Ly6G-Ly6ClowMHCIIlow) differentiation by binding to its receptor Nrp1, and increases M1-Mφs proliferation but represses M2-Mφs by enhancing CSF1-mediated phosphorylation of Akt and MAPK, inducing CD8+ T cells and NK cells to repress tumor growth (27).