# Poly-(D,L)-Lactide-ε-Caprolactone-Methacrylate Is a Suitable Scaffold Material for In Vitro Cartilage Regeneration

## TL;DR

This study evaluates biodegradable polymer scaffolds for cartilage regeneration, finding that poly-(D,L)-lactide-ε-caprolactone-methacrylate (LCM) is more suitable than other materials in a 2D in vitro model.

## Contribution

The study introduces and compares LCM and ACM as novel scaffold materials for cartilage repair, with insights into their chondrogenic potential.

## Key findings

- LCM supports better chondrogenic differentiation than ACM in 2D cultures.
- Heparin coating does not improve the performance of LCM or ACM.
- Collagen type II levels increase on LCM, LCMH, and ACM discs by day 20.

## Abstract

Due to the limited regeneration of cartilage, new implant materials are needed. Biodegradable polymers poly-(D,L)-lactide-ε-caprolactone-methacrylate (LCM) and polyamid-ε-caprolactone-methacrylate (ACM) were recently established and coated with heparin, making them able to prevent blood coagulation and cartilage mineralization. The aim of this study was to analyze the suitability of LCM and ACM alone or coated with heparin (the latter are abbreviated as LCMH and ACMH, respectively) as implant material for cartilage repair. Therefore, mesenchymal stem cells were chondrogenically differentiated in 2D cultures with polymer discs. Differentiation was induced by the supplementation of cell medium with dimethyloxalylglycine, TGF-β, and BMP2. After 5 days, no increase in proinflammatory factors was observed. Cell viability declined on ACM and ACMH discs. During early chondrogenesis, SOX9 expression increased on LCM and LCMH discs, while TRPV4 expression decreased on ACMH discs. At day 20, the level of collagen type II increased on LCM, LCMH, and ACM discs, demonstrating the ability of chondrogenic development on these implants. In summary, coating with heparin showed no advantages compared to pure LCM and ACM. For cartilage repair, LCM is more suitable than ACM in this 2D in vitro model, which needs to be verified by long-term 3D models and in vivo studies.