The impact of surface modification with Thrombospondin-1 on biomaterial integration of porous polyethylene implants

Introduction Porous polyethylene (PPE) implants are utilized in craniomaxillary surgery for reconstruction of bone and cartilage defects. The matrix glycoprotein thrombospondin-1 (TSP-1) is attributed pro- as well as anti-angiogenic properties. Using the method of dorsal skinfold chamber on TSP-1 knock-out mice, it was evaluated that in absence of TSP-1 biomaterial integration of PPE-implants is impaired concerning vascularisation and leukocyte-endothelial interaction. In this study we examined whether a surface modification with TSP-1 favours independently of the influence of the adaptive immune system the BI of PPE-implants.

Methods PPE-implants were either treated with TSP-1 (n=20) or VEGF-A (n=10) and subsequently implanted in the chorioallantoic membrane. Implants were then examined for a period of ten days with intravital microscopy regarding angiogenesis and implant integration. Implants treated with NaCl (n=13) or untreated (n=7) implants were used as control.

Results The experimental group treated with VEGF-A showed significantly increased functional vessel density in the adjacent tissue. TSP-1 treatment did not affect vascular parameters in comparison to the two control groups. Concerning vascularisation of the implant body no statistically significant differences occured.

Conclusions VEGF-A showed an pro-angiogenic impact. Despite the reduced neoangiogenesis in TSP-1 knockout mice in context of BI, a surface modification with TSP-1 did not exhibit any pro-angiogenic effects in the immunodeficient CAM Assay. The experimental results suggest a predominantly immune-mediated influence of TSP-1 on angiogenesis regarding BI.

Das Projekt wurde personenbezogen finanziell durch die Graduiertenschule Mainz Research School of Tranlational Medicine (TransMed) innerhalb der Johannes Gutenberg – Universität Mainz, Mainz unterstützt.

Publikationsverlauf

Artikel online veröffentlicht:
24. Mai 2022