The role of aV Integrin in regulating macrophage phenotype and function during cardiac remodeling after myocardial infarction

Macrophages infiltrate the infarcted heart and play a critical role in repair, remodeling and fibrosis. Macrophages sense changes in the extracellular matrix (ECM) environment through Integrins, thus activating signaling pathways that regulate their function. Our data show that av integrin is highly expressed in isolated bone marrow macrophages and is markedly upregulated in response to TGF-ß, a growth factor known to be activated in the infarcted heart. Accordingly, we hypothesize that aV integrin induction in infarct macrophages may regulate macrophage phenotype, function and response to key macrophage-activating signals following MI. Overall design: In order to study the role of integrin aV in mmacrophages in vitro, we isolated bone marrow macrophages from WT mice and grow them in fibronectic coated and normal culture dishes, and treated them with a anti-integrin aV neutralizing antibody and its control (IgG).