New publication: SINPAIN research advances promising hydrogels for cartilage regeneration

A study by the SINPAIN team at AO Research Institute provides important insights into the development of bioactive hydrogels for cartilage repair. It shows how combining cartilage-derived biological components with hyaluronic acid-based hydrogels as well as choosing the right crosslinking method can improve both their mechanical and biological properties.

In the publication entitled “Crosslinking Strategy Determines the Biomechanical and Biological Performance of Decellularized Extracellular Matrix Particle–Hyaluronic Acid Hydrogels for Cartilage Regeneration”, advanced biomaterials were investigated designed to create a supportive environment for cartilage cells and promote tissue regeneration. Cartilage has a limited ability to repair itself after damage, making new regenerative approaches particularly important for conditions such as osteoarthritis. The study focuses on hydrogels made from tyramine-modified hyaluronic acid (THA) combined with particles of decellularized extracellular matrix (dECM). dECM retains proteins and other biological components of cartilage while the original cells are removed, providing valuable signals that can support cartilage cells.

Researchers compared two methods for crosslinking the hydrogel network: horseradish peroxidase/Eosin (HRP/Eo) and sodium persulfate/ruthenium (SPS/Ru).

Key findings:

Adding dECM particles significantly improved the mechanical properties of the hydrogels with both methods. Under the conditions tested, the HRP/Eo-crosslinked hydrogels performed particularly well:

• dECM particles were integrated more evenly into the hydrogel network;
• more glycosaminoglycans (GAGs) and collagen, key components of cartilage, were retained;
• the hydrogels showed greater mechanical stiffness during early cell culture; and
• cartilage cells remained viable and showed higher expression of type II collagen (COL2), an important marker of cartilage formation.

The findings demonstrate how the design and processing of biomaterials can influence their physical properties as well as their interaction with cartilage cells. Combining dECM particles with HRP/Eo-crosslinked hyaluronic acid hydrogels could therefore offer a promising route towards improved biomaterials for cartilage regeneration.

Further studies will investigate their longer-term performance, including mechanical stability and degradation.