Practical application of this assay system enables us to use FC measurement more widely in clinical practice. “
“Cao S, Yaqoob U, Das A, Shergill U, Jagavelu K, Huebert RC, et al. Neuropilin-1 promotes cirrhosis of the rodent and human liver by enhancing PDGF/TGF-beta signaling

in hepatic stellate cells. J Clin Invest 2010;120:2379-2394. (Reprinted with permission.) PDGF-dependent hepatic stellate cell (HSC) recruitment is an essential step in liver fibrosis and the sinusoidal vascular changes that accompany this process. However, the mechanisms that regulate PDGF signaling remain incompletely defined. Here, we found that in two rat models of Torin 1 liver fibrosis, the axonal guidance molecule neuropilin-1 (NRP-1) was upregulated in activated HSCs, which exhibit the highly motile myofibroblast phenotype. Additionally, NRP-1 colocalized with PDGF-receptor beta (PDGFRbeta) in HSCs both in the injury models and in human and rat HSC cell lines. In human HSCs, siRNA-mediated knockdown of NRP-1 attenuated PDGF-induced chemotaxis, while NRP-1 overexpression increased cell motility and TGF-beta-dependent collagen production. Similarly, mouse HSCs genetically modified to lack NRP-1 displayed reduced motility in response to PDGF treatment. Immunoprecipitation and biochemical binding

studies revealed that NRP-1 increased PDGF binding affinity for PDGFRbeta-expressing cells and promoted downstream signaling. An NRP-1 neutralizing Ab ameliorated recruitment of HSCs, blocked liver fibrosis in a rat model of liver injury, and buy 3-MA also attenuated

VEGF responses in cultured liver endothelial cells. In addition, NRP-1 overexpression was observed in human specimens of liver cirrhosis caused by both hepatitis C and steatohepatitis. These studies reveal a role for NRP-1 as a modulator of multiple growth factor targets that regulate liver fibrosis and the vascular changes that accompany it and may have broad implications for liver cirrhosis and myofibroblast biology in a variety of other organ systems and disease conditions. Chronic liver disease afflicts millions of patients and is among the 10 leading causes of death in the United States.1 The great this website majority of chronic liver disease is caused by hepatitis B, hepatitis C, nonalcoholic fatty liver disease, and alcoholic liver disease. In most cases, these diseases progress slowly over several decades in characteristic stages, with hepatic fibrosis setting the stage for the development of cirrhosis and, in some cases, hepatocellular carcinoma (HCC). Hepatic stellate cells (HSCs) have emerged as the main profibrogenic cell type in the liver, and the transformation from quiescent, vitamin A storing to activated HSCs with a myofibroblastic phenotype is believed to be a key event in the progression to fibrosis and cirrhosis.