Fibronectin upregulates gelatinase B (MMP-9) and induces coordinated expression of gelatinase A (MMP-2) and its activator MT1-MMP (MMP-14) by human Tlymphocyte cell lines. A process repressed through RAS/MAP kinase signaling pathways

T-lymphocyte migration into tissues requires focal degradation of the basem ent membrane. In this study, we show that transient adherence to fibronecti n induces the production of activated forms of matrix metalloproteinase-2 ( MMP-2) and MMP-9, as well as downregulation of tissue inhibitor of metallop roteinase-2 (TIMP-2) by T-cell lines. MMP-2 activation was likely achieved by inducing a coordinated expression of membrane-type matrix metalloprotein ase-1 (MMP-14), a major activator of MMP- 2. Blocking monoclonal antibodies against alpha 4, alpha 5, and alpha v integrins strongly reduced MMP-2 and MMP-9 production induced by fibronectin. Disrupting actin cytoskeleton org anization by cytochalasin D strongly enhanced fibronectin-induced MMP-2 and MMP-9 expression, Inhibiting Src tyrosine kinases with herbimycin A reduce d MMP-2 and MMP-9 production with no effect on cell attachment. By contrast , G-protein inhibition by pertussis toxin, or transfection with a dominant negative mutant of Ha-Res strongly increased fibronectin-induced MMP-2 and MMP-9. Inhibition of PI3 kinase, MAPkinase (MEK1), or p38 MAPkinase by wort mannin, PD 98059, or SE 202190, respectively, strongly promoted fibronectin -induced MMP2 and MMP-9. Cells at high density lost their ability to synthe size MMP-2 and MMP-9 in response to fibronectin and MMP expression was rest ored by transfection with a dominant-negative mutant of Ha-Ras or by treatm ent with wortmannin, PD 98059, or SE 202190. Our findings suggest that adhe sion to fibronectin transduces both stimulatory (through Src-type tyrosin k inases) and inhibitory signals (through Ras/MAPKinase signaling pathways) f or MMP-2 and MMP-9 expression by T lymphocytes and that their relative pred ominance is regulated by additional stimuli related to cell adhesion, motil ity, and growth. (C) 1999 by The American Society of Hematology.