Cartilage tissue engineering based on chondrogenic cells seeded onto biodegradable polymer supports and cultivated in bioreactors can potentially become an effective method for creating functional tissue equivalents. Cultivation in perfused bioreactors can improve the uniformity and structure of the engineered tissues. We report studies of two different supports for immunobilization of mouse bone marrow stromal cells (BMSC) for cultivation in perfused bioreactors: fibrous polyglycolic acid (PGA) scaffolds and alginate microbeads.