Regulatory components of the alternative complement pathway in endothelial cell cytoplasm, factor H and factor I, are not packaged in Weibel-Palade bodies.

ABSTRACT: It was recently reported that factor H, a regulatory component of the alternative complement pathway, is stored with von Willebrand factor (VWF) in the Weibel-Palade bodies of endothelial cells. If this were to be the case, it would have therapeutic importance for patients with the atypical hemolytic-uremic syndrome that can be caused either by a heterozygous defect in the factor H gene or by the presence of an autoantibody against factor H. The in vivo Weibel-Palade body secretagogue, des-amino-D-arginine vasopressin (DDAVP), would be expected to increase transiently the circulating factor H levels, in addition to increasing the circulating levels of VWF. We describe experiments demonstrating that factor H is released from endothelial cell cytoplasm without a secondary storage site. These

SUBMITTER: Turner NA 

PROVIDER: S-EPMC4372330 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature