Outgrowth of chondrocytes from human articular cartilage explants and expression of alpha-smooth muscle actin.

:The objectives of this study were to investigate the effect of various enzymatic treatments on the outgrowth of chondrocytes from explants of adult human articular cartilage and the expression of a specific contractile protein isoform, alpha-smooth muscle actin, known to facilitate wound closure in other connective tissues. Explants of articular cartilage were prepared from specimens obtained from patients undergoing total joint arthroplasty. The time to cell outgrowth in vitro was determined and the expression of alpha-smooth muscle actin shown by immunohistochemistry. Treatment of the explants with collagenase for 15 minutes reduced the time to outgrowth from more than 30 days to 3 days. Hyaluronidase, chondroitinase ABC, and trypsin applied for the 15-minute period had no effect on the time to cell outgrowth when compared with untreated controls. Pretreatment with hyaluronidase prior to collagenase reduced the time to outgrowth. A notable finding of this study was that the majority of chondrocytes in the adult human articular cartilage specimens and virtually all of the outgrowing cells contained alpha-smooth muscle actin. We conclude that human articular chondrocytes have the capability to migrate through enzymatically degraded matrix and express a contractile actin isoform. Collagenase treatment reduces the time required for cell outgrowth.

Qiu W ，Murray MM ，Shortkroff S ，Lee CR ，Martin SD ，Spector M ... -  《WOUND REPAIR AND REGENERATION》

Healing of defects in canine articular cartilage: distribution of nonvascular alpha-smooth muscle actin-containing cells.

Wang Q ，Breinan HA ，Hsu HP ，Spector M ... -  《WOUND REPAIR AND REGENERATION》

Specific enzymatic treatment of bovine and human articular cartilage: implications for integrative cartilage repair.

Bos PK ，DeGroot J ，Budde M ，Verhaar JA ，van Osch GJ ... -  《ARTHRITIS AND RHEUMATISM》

Smooth muscle actin expression by human articular chondrocytes and their contraction of a collagen-glycosaminoglycan matrix in vitro.

Kinner B ，Spector M 《JOURNAL OF ORTHOPAEDIC RESEARCH》

Distribution of chondrocytes containing alpha-smooth muscle actin in human articular cartilage.

Kim AC ，Spector M 《JOURNAL OF ORTHOPAEDIC RESEARCH》