Vitronectin promotes the vascularization of porous polyethylene biomaterials

Introduction:

Porous polyethylene (PPE) implants are successfully used for orbital floor, auricular, and facial contour reconstruction in clinical routine. However, there are less favorable sites for implantation of this biomaterial including irradiated and scarred tissues as well as anatomical sites characterized by weak blood supply. Rapid implant vascularization is a prerequisite for successful biomaterial engraftment. Vitronectin (VN) is a matricellular glycoprotein well known for its capability to interact with growth factors, proteases, and protease inhibitors/receptors. Since such proteins are highly relevant for angiogenic processes, we hypothesized that VN contributes to the tissue integration of biomaterials.

Methods:

Engraftment of PPE implants was analyzed by in vivo microscopy in the dorsal skinfold chamber model in wild-type (WT) and VN deficient mice. Angiogenesis-related proteins in PPE implants were identified by a proteome profiling array.

Results:

Upon PPE implantation, vascularization of this biomaterial was severely compromised in VN deficient animals. Proteome profiling revealed that VN deficiency does not cause major changes in angiogenic protein composition in the implants suggesting that VN promotes PPE vascularization via mechanisms modulating the activity of angiogenic factors rather than by directly enriching them in the implant. Consequently, surface coating with recombinant VN accelerated implant vascularization in WT mice by enhancing the maturation of a vascular network.

Conclusions:

VN contributes to the engraftment of PPE implants by promoting the vascularization of this biomaterial. Surface coating with VN might provide a promising strategy to improve the vascularization of PPE implants without affecting the host's integrity.

Publication History

Publication Date:
23 April 2019 (online)