Angiogenesis and Collagen Type IV Expression in Different Endothelial Cell Culture Systems

Abstract

In vitro angiogenesis assays constitute an important tool for studying the mechanisms of angiogenesis and for identification of pro- and anti-angiogenic substances. Therefore, endothelial cell and media systems used for in vitro angiogenesis assays are required to mimic the angiogenic process in vivo including endothelial capability to express collagen type IV as a component of the basement membrane. In this study, the expression of collagen type IV and its α chains (α1-6) was investigated in different endothelial cell culture systems in vitro qualitatively and quantitatively. These systems included four different batches of microvascular endothelial cells derived from the human skin, heart and lung, from which only two batches were found to be angiogenic and two batches were classified as non-angiogenic. Distribution of the transcripts of the α chains of collagen type IV was similar in all cell and media systems investigated. However, secretion and deposition of a stable extracellular network of collagen type IV could only be observed in the angiogenic cultures. In conclusion, the consecutive steps of the angiogenic cascade in vivo as well as in vitro depend on an increasing secretion and subsequent extracellular deposition of collagen type IV.

Collagen type IV remodelling gender‐specifically predicts mortality in decompensated cirrhosis

“…In this study, collagen type IV turnover markers are significantly higher in patients with varices, suggesting an association with vascular formation and perisinusoidal fibrosis. In fact, angiogenesis has been shown to be dependent on increasing and subsequent extracellular deposition of collagen type IV . This could indicate a role of collagen type IV in angiogenesis of decompensated cirrhosis.…”

SNAI1, an endothelial–mesenchymal transition transcription factor, promotes the early phase of ocular neovascularization

“…(typical photographs of 3 pairs of sample were showed). *P < 0.05, **P < 0.01, ***P < 0.001 Bar = 100 μm ◂ fibronectin, and collagen type IV [47]. The former process required a series of diffusing and membrane-bound proteolytic enzymes, which mainly fell into two classes: PA and MMPs [3].…”

Macrophages significantly enhance wound healing in a vascularized skin model

“…The sections were also stained by applying a rabbit anti‐human pan‐cytokeratin primary antibody (1:100; Acris Antibodies) and an Alexa Fluor® 488 goat anti‐rabbit IgG secondary antibody (1:400; Thermo Fisher Scientific) to visualize keratinocyte layer development. Endothelial cells and keratinocytes secrete collagen IV which is part of the basement membrane and extracellular matrix . Thus, the basement membrane composed of type IV collagen was visualized using a rabbit anti‐human collagen IV primary antibody (1:100; Acris Antibodies) labeled with an Alexa Fluor 488 goat anti‐rabbit secondary antibody (1:400).…”