Arteriogenesis requires toll-like receptor 2 and 4 expression in bone-marrow derived cells

►Toll Like Receptor-2 and -4 are involved in arteriogenesis. ►The absence of TLR-2 and -4 deteriorates collateral formation and thereby tissue perfusion after arterial occlusion. ►The TLR-2 and -4 expression during arteriogenesis is mainly restricted to infiltrating leukocytes. ►Bone-marrow transplantation shows that TLRs on bone marrow derived cells are essential for arteriogenesis.