Design principles for lymphatic drainage of fluid and solutes from collagen scaffolds.

In vivo, tissues are drained of excess fluid and macromolecules by the lymphatic vascular system. How to engineer artificial lymphatics that can provide equivalent drainage in biomaterials remains an open question. This study elucidates design principles for engineered lymphatics, by comparing the rates of removal of fluid and solute through type I collagen gels that contain lymphatic vessels or unseeded channels, or through gels without channels.

Crosslinking of collagen scaffolds promotes blood and lymphatic vascular stability.

The low stiffness of reconstituted collagen hydrogels has limited their use as scaffolds for engineering implantable tissues. Although chemical crosslinking has been used to stiffen collagen and protect it against enzymatic degradation in vivo, it remains unclear how crosslinking alters the vascularization of collagen hydrogels. In this study, we examine how the crosslinking agents genipin and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide alter vascular stability and function in microfluidic type I collagen gels in vitro.