Phosphotyrosine protein activation and identification in adherent U-937 macrophages mediated by Fibronectin Domains

Abstract

Fibronectin (FN)-derived oligopeptides were developed to probe the molecular mechanisms of ligand-receptor binding, post-ligation intracellular signalling and phenotypic expression of human macrophages. The baseline adhesion kinetics of U-937 was established and utilized to maximize the amount of intracellular proteins that could be collected and analyzed. Time points up to 24 h were chosen to minimize the contribution of post-adhesion cell proliferation and/or phenotype changes as not to askew the ligand-mediated adhesion result and the subsequent analyses. The identification of these proteins provide insights into the critical modulatory factors in monocyte-surface interactions.