Adhesion molecules in the glomerular mesangium

Abstract

Experimental evidence indicates that extensive "cross-talk" exists between glomerular cells, extracellular matrix molecules and soluble mediator substances affecting the proliferative and secretory phenotype of glomerular mesangial cells. Both matrix and cytokines regulate mesangial cell behavior in vitro and in vivo after binding to specific cell surface receptors. It appears as if the concerted action of insoluble and soluble ligands on mesangial cells involves a reciprocal regulation of matrix molecules and cytokines as well as expression and affinity of their respective receptors. Elucidation of the potential biologic and clinical relevance of cell-matrix interactions in the glomerular mesangium represents a challenging goal in current kidney research. This brief review summarizes recent investigations concerning regulation of expression and function of adhesion molecules and matrix receptors in the mesangium. In addition to results from cell culture studies, descriptive findings on expression and regulation of adhesion molecules and their potential role for altered mesangial cell behavior in glomerular disease is considered.

CTGF Mediates TGF-β–Induced Fibronectin Matrix Deposition by Upregulating Active α5β1 Integrin in Human Mesangial Cells

“…The ␣5␤1 integrin receptor is essential for fibronectin matrix assembly (24) and is expressed by many cell types, including mesangial cells (37). TGF-␤ and CTGF were both shown to increase fibronectin matrix deposition by mesangial cells; we therefore examined whether this was related to differences in the level of cell-surface ␣5␤1 integrin receptor.…”

“…Mesangial cells express an array of integrin receptors that are able to bind fibronectin (37). Thus, to assess the importance of ␣5␤1 integrin in mediating mesangial cell adhesion to fibronectin, we treated cells with BIIG2 (20 g/ml), an antibody to the ␣5 integrin receptor that blocks cell attachment to fibronectin (36), before seeding onto fibronectin.…”

Early diagnosis of acute kidney injury

“…In 1997 Gauer et al were able to verify that ICAM-1 is expressed in the area of the kidneys only if kidney damage occurs [1,24]. Their observations suggest a control function of sICAM-1 for preventing uncontrolled apoptosis and the irreversible destruction that occurs with it [25].…”

Tensin Is Expressed in Glomerular Mesangial Cells and Is Related to Their Attachment to Surrounding Extracellular Matrix

“…In such cell-matrix adhesion sites, several actin-associated proteins, including ␣ -actinin, talin, and vinculin, have been identified (Drenckhahn and Franke 1988;Drenckhahn et al 1990;Prols et al 1999). These proteins bind actin and integrin, and some of them are related to signal transduction (Gauer et al 1997;Prols et al 1999). It is generally considered that ␣ 8 integrin is specific for MCs Bieritz et al 2003).…”

“…The mesangial cell (MC) has several functions, such as maintenance of glomerular capillary architecture (Sakai and Kriz 1987;Lemley et al 1992), phagocytosis of macromolecules, and immune complexes (Schlondorff and Mori 1990;Hughes et al 1997;CortesHernandez et al 2002), and production of bioactive substances (Busiek et al 1995;Diaz-Cazorla et al 1999;Rovin et al 2001). MC-matrix interactions at the MC processes may play an important role in MC function (Drenckhahn et al 1990;Gauer et al 1997). In the cell processes, actin microfilament bundles connect to the glomerular basement membrane (GBM) through the interposition of integrin transmembrane protein (Drenckhahn et al 1990).…”