Synthetic biodegradable microparticles for articular cartilage tissue engineering

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Cell Biology

Background:

• Articular cartilage repair necessitates in vitro expanded chondrocytes.
• Prolonged chondrocyte expansion can alter cell phenotype.
• Microcarrier cultures offer a method to expand cells while preserving phenotype.

Purpose of the Study:

• To evaluate poly(lactide-co-glycolide) (PLGA) microparticles for chondrocyte expansion in cartilage tissue engineering.
• To investigate the impact of PLGA particle shape and surface modification on chondrocyte behavior.
• To assess the potential of PLGA microcarriers in promoting hyaline-like cartilage formation.

Main Methods:

• PLGA microspheres and microparticles (47-210 microm) were surface-modified via ammonia plasma/collagen or hydrolysis/dendrimer immobilization.
• Surface modifications were characterized using X-ray photoelectron spectroscopy.
• In vitro chondrocyte cultures and in vivo cartilage formation assays in nude mice were performed.

Main Results:

• Chondrocyte proliferation rate was significantly affected by PLGA particle shape and surface chemistry.
• Cell phenotype was maintained irrespective of particle shape or surface chemistry.
• In vivo, PLGA microspheres facilitated the formation of hyaline-like cartilage and reduced collagen gel contraction.

Conclusions:

• PLGA microcarriers are effective for chondrocyte expansion, maintaining phenotype for cartilage tissue engineering.
• Surface chemistry and particle shape are critical factors for optimizing chondrocyte proliferation.
• PLGA microspheres show promise in improving cartilage tissue formation and stability.