Is collagen type II antiangiogenic in printed scaffolds for cartilage tissue engineering?

Abstract

Cartilage is an avascular tissue, which becomes vascularized during arthritis. The main component of cartilage is collagen type II. We want to know if collagen type II has antiangiogenic properties or if chondrocytes release antiangiogenic factors responsible for avascular cartilage. Evidence shows that endothelial cells produce matrix metalloproteinases that degrade collagen type II and express integrins to attach to collagen type II. Thus making vessel ingrowth possible and suggesting that collagen type II in itself is not antiangiogenic. Our second question deals with the feasibility of printing collagen type II using a fiber deposition system. Collagen type I gels have been printed simply diluted with DMEM or by adding thickeners such as alginate, fibrinogen or hyaluronic acid. As collagen type I and II are similar, we suggest printing collagen type II mixed with chondrocytes and if necessary the thickeners. In conclusion, collagen type II is not antiangiogenic and it is feasible to print collagen type II scaffolds.