Apolipoprotein (a) impairs endothelial progenitor cell-mediated angiogenesis.

Improvement of blood flow and promotion of angiogenesis are important therapeutic measures for the treatment of ischemic peripheral vascular diseases. Since apolipoprotein (a) (apo (a)) is a glycoprotein with repetitive kringle domains exhibiting 75% to 98% structural homology with plasminogen (Plg), apo (a) may also have a negative effect on endothelial progenitor cell (EPC)-induced angiogenesis through Plg-like inhibitory effects on EPC proliferation, adhesion, migration, and angiogenesis. To evaluate the effect of apo (a) on EPCs-induced angiogenesis, EPCs were isolated from the bone marrow of apo (a) transgenic mice, wild-type litter mates, and normal mice. These cells were cultured without or with apo (a) before transplantation. Hindlimb ischemia models were surgically induced in mice, which then received an intravenous injection of 3×105 EPCs. At 3, 7, and 14 days post EPC transplantation, the adhesion, migration abilities, and capillary density in calf muscles were assessed. Results indicate that a...