Mesangial Cell αvβ8 Integrin Regulates Glomerular Capillary Integrity and Repair.

Mesangial Cell αvβ8 Integrin Regulates Glomerular Capillary Integrity and Repair. Am J Physiol Renal Physiol. 2014 Apr 16; Authors: Lakhe-Reddy S, Li V, Arnold TD, Khan S, Schelling JR Abstract Integrin αvβ8 is most abundantly expressed in kidney, brain and female reproductive organs, and its cognate ligand is latent transforming growth factor-β (LTGFβ). Kidney αvβ8 localizes to mesangial cells, and global Itgb8 deletion results in embryonic lethality due to impaired placentation and cerebral hemorrhage. To circumvent the lethality, and better define kidney αvβ8 function, Cre-lox technology was used to generate mesangial-specific Itgb8-null mice. PDGFBR-Cre mice crossed with a reporter strain revealed functional Cre recombinase activity in a predicted mesangial pattern. However, mating between two different PDGFBR-Cre or Ren(1d)-Cre strains with Itgb8(flox/-) mice consistently resulted in incomplete recombination, with no renal phenotype in mosaic offspring. Induction of a renal phenotype with Habu snake venom, a reversible mesangiolytic agent, caused exaggerated glomerular capillary microaneurysms and delayed recovery in Cre(+/-)PDGFRB(flox/-) mice compared to Cre(+/-)PDGFRB(flox/+) controls. To establish the mechanism, in vitro studies were conducted in Itgb8-null versus Itgb8-expressing mesangial cells and fibroblasts, which revealed β8-regulated adhesion to Arg-Gly-Asp (RGD) peptides within mesangial-conditioned matrix...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research