Scientists identify molecular response of cartilage to injury

Washington, May 9 : A new study has shed light on how injury to joint cartilage raises a person's risk of developing osteoarthritis (OA), by identifying the molecular response of cartilage to injury.

An international team of rheumatologists and biotechnologists conducted a microarray screening of adult human joint cartilage subjected to injury.

The team reported the full-genome characterization of the moleculer response of adult human articular cartilage to mechanical injury.

During the study, the gene expression profile of cartilage explants 24 hours after mechanical injury was compared to that of uninjured control explants using microarray technology.

The explants were obtained either from uninvolved cartilage areas of knees affected by OA or from healthy cartilage from one individual who underwent a limb amputation following a road traffic accident.

The expression of selected genes was then confirmed using real time PCR and immunohistochemistry.

The study showed that in injured samples, a total of 690 genes were significantly either up- or down regulated at least 2-fold compared with expression in the uninjured samples.

Significant clusters included genes associated with cell signalling, wound healing, and skeletal development, as well as genes previously found to be differentially expressed in OA cartilage.

The study led by Dr. Francesco Dell'Accio, a clinician scientist fellow of the Arthritis Research Campaign indicated that several genes encoding signalling molecules are regulated following cartilage injury in adult individuals.

However, Dr Dell'Accio said that further investigation is needed "to optimally target the respective pathways to promote joint surface cartilage defect repair or to stop further joint surface breakdown, thereby preventing the development of posttraumatic OA."

The study appears in the May issue of Arthritis and Rheumatism.

ANI