Abstract: Objective To investigate the influence of the bone marrow-derived mast cells (BMMCs) on the expression of type II
collagen and glycosaminoglycan (GAG) in chondrocytes co-cultured with BMMCs. Methods Primarily cultured mouse
BMMCs at 4 weeks and the second passage of chondrocytes were plated in a Transwell co-cultured system at a ratio of 1∶10 in
the presence or absence of sodium cromoglycate (DSCG) or compound 48/80 (C48/80). The chondrocytes were harvested and
lysed for detecting type II collagen expression with ELISA and Western blotting and GAG expression using 1,9
dimethylmethylene blue (DBM). Results After a 24-hour culture, the chondrocytes co-cultured with BMMCs showed similar
expression levels of type II collagen and GAG to the control group regardless of the presence of DSCG (P>0.05). Compared
with chondrocytes cultured alone or with BMMCs, the co-cultured chondrocytes in the presence of C48/80 showed
significantly lower expressions of type II collagen and GAG (P<0.01). Such results did not vary significantly as the culture time
was extended to 48 h. Conclusions C48/80-activated BMMCs can reduce the expression of type II collagen and GAG in
chondrocytes in the co-culture system.