Tissue response in the rat and the mouse to degradable dextran hydrogels

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Hydroxyethyl-methacrylated dextran (dex-HEMA) hydrogels are utilized in biomedical applications.
• Understanding their degradation and host tissue response is crucial for safe and effective use.

Purpose of the Study:

• To compare the local tissue responses and degradation characteristics of two dex-HEMA hydrogels with different crosslink densities.
• To evaluate these responses in both mice and rats over a 13-week period.

Main Methods:

• Subcutaneous implantation of dex-HEMA hydrogels (DS5 and DS13) in rats and mice.
• Histological evaluation of tissue response at 2, 6, and 13 weeks post-implantation.
• Assessment of hydrogel degradation and capsule formation.

Main Results:

• Rats exhibited a mild inflammatory response with faster degradation of DS5 hydrogels.
• Mice showed a more pronounced inflammatory response, including capsule formation and ulceration, with slower degradation.
• DS5 hydrogels degraded more completely than DS13 hydrogels in both species.
• Histological differences diminished by week 13.

Conclusions:

• Species-specific differences in tissue response to dex-HEMA hydrogels were observed.
• Degradation rate is influenced by the degree of HEMA substitution, with lower substitution leading to faster degradation.
• Dex-HEMA hydrogels demonstrate variable biocompatibility and degradation profiles depending on the host species and substitution level.