Isolation and characterization of peritoneal microvascular pericytes.

As a potential source of myofibroblasts, pericytes may play a role in human peritoneal fibrosis. The culture of primary vascular pericytes in animals has previously been reported, most of which are derived from cerebral and retinal microvasculature. Here, in the field of peritoneal dialysis, we describe a method to isolate and characterize mouse peritoneal microvascular pericytes. The mesenteric tissues of five mice were collected and digested by type II collagenase and type I DNase. After cell attachment, the culture fluid was replaced with pericyte-conditioned medium. Pericytes with high purity (99.0%) could be isolated by enzymatic disaggregation combined with conditional culture and magnetic activated cell sorting. The primary cells were triangular or polygonal with protrusions, and confluent cell culture could be established in 3 days. The primary pericytes were positive for platelet-derived growth factor receptor-β, α-smooth muscle actin, neuron-glial antigen 2, and CD13. Moreover, they promoted formation of endothelial tubes, and pericyte-myofibroblast transition occurred after treatment with transforming growth factor-β1. In summary, we describe here a reproducible isolation protocol for primary peritoneal pericytes, which may be a powerful tool for in vitro peritoneal fibrosis studies.