IFN-gamma and transforming growth factor-beta 1 differently regulate fibronectin and laminin receptors of human differentiating monocytic cells.

摘要: The regulation of extracellular matrix (ECM) protein receptor expression was followed in the human promonocytic cell line U937 before and after stimulation either with PMA or various cytokines implicated monocytopoiesis. On undifferentiated cells, alpha-chains very late Ag (VLA)-4, VLA-5, VLA-6 were constitutively expressed whereas VLA-2 (alpha 2) vitronectin V) not. Maturation cells resulted a marked decrease alpha 4 (25% control by day 5), small but significant increase 2 v over days stimulation. Unstimulated attached to fibronectin (FN) not laminin (LM), collagens I/IV-coated surfaces. After stimulation, exhibited enhanced adherence on FN ability adhere LM. also promoted spreading both Adhesion all along maturation pathway specifically totally inhibited anti-alpha 5 mAb mAb. Anti-beta 1, 6, 2, mAb, as well Tyr-Ile-Gly-Ser-Arg Arg-Gly-Asp synthetic peptides from LM, had no effect adhesion PMA-stimulated implying that LM is mediated through hitherto distinct receptors. In presence rIFN-gamma, differentiating did lost capacity bind FN. Loss correlated concomitant integrin subunits. contrast, TGF-beta 1 mimicked most effects enhancing attachment maturating receptors promoting FN- LM-coated data suggest inflammatory such IFN-gamma may be critically important homing monocytic at sites inflammation modulating cell-surface ECM