Table 1.
Islet Vascular Cell Features (Summary Table).
| Feature | Endothelial cells | Pericytes |
|---|---|---|
| Cell markers | CD31 (117, 118) CD146, CD105 (118) nephrin (119) von Willebrand’s factor (118) |
NG2, PDGFR β (120) |
| Known effects on β -cells | Gene expression (25) Insulin secretion (7) Replication (5, 25) |
Gene expression (26, 27, 77) GSIS (23, 26, 27) Replication (22) Regulation of islet blood flow (21) |
| Factors secreted | Connective tissue growth factor (CTGF) (53) Thrombospondin (TSP)-1 (60) |
Nerve growth factor (NGF) (23) Bone morphogenetic protein 4 (BMP4) (26) |
| Basement membrane components produced | Collagen IV Laminin α4 Laminin α5 (25) |
Collagen IV Laminin α2 Laminin α4 Nidogens Perlecans (77) |
| Immunoregulatory function | Recruit pancreatic macrophages (5) | Unknown in pancreas Leukocyte trafficking/activation in brain and kidney (32–34) Production of anti-inflammatory factors (33, 121, 122) |
| Implications in diabetes | Activation of AGE receptors may contribute to progressive complications (115) Alterations of vasculature in diabetic islets (107) and secreted basement membrane (106) associated with disease-related islet damage (105) and malfunction (107) |
Type 2 diabetes is associated with a reduced density (21) Support of β-cells depends on the diabetes gene TCF7L2 (26) Transform to myofibroblast during stress (96) |