EF- 40-2016 Complement: An Unfinished Symphony.

EF- 40-2016 Complement: An Unfinished Symphony. Am J Physiol Renal Physiol. 2016 May 4;:ajprenal.00250.2016 Authors: Ward PA Abstract The current issue reports that, when hypertension was induced in mice (using infusion of angiotensin II and with NaCl in the drinking water), the absence (knockout) of the first receptor for C5a (C5aR1) resulted in reduced albuminuria but increased amounts of interstitial collagen deposition in the heart. The role of the second C5a receptor (C5aR2) in responses to hypertension was not examined, but should be. Such patterns suggest that mice lacking C5aR1 express different outcomes during hypertension in the heart and in the kidneys. We review different strategies for blockade of complement activation products in order to prevent organ injury due to complement activation. We also emphasize the need to extend the new studies to define the outcomes in hypertensive mice that lack the second C5a receptor, C5aR2. Finally, we describe recent studies demonstrating that in CD4+ T cells intracellular C3 present and is activated (cleaved) by cathepsin enzyme L, resulting in generation of C3a and C3b, which appear to be essential for robust T cell function. Such observations suggest a new pathway of complement activation, namely, intracellular activation of complement, which represents an entirely new aspect of the complement system, with substantial implications. PMID: 27147673 [PubMed - as supplied by pu...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research