Improved cell therapy for cartilage repair

Dec 2 2006

Artificially cultured cartilage cells, grown outside of the body for reparing damaged tissue, prove to be different from original cartilage tissue.

Cell therapy may be successful, but the added tissue performs worse than the orginal. PhD student Jeanine Hendriks of UT's Institute for Biomedical Technology (BMTI) has developed a better method. She adds primary cells, still 'knowing' how to form a cartilage matrix, to the cultured cells. This seems to be a promising technique for improving cell therapy results.

Cartilage has unique properties, thanks to a matrix of cells. The 'proteoglycanes' within this matrix are capable of binding water: if cartilage is under pressure, this water is squeezed out, does pressure get lower again, the water is bound again as well. This improves the flexibility of cartilage substantially, and is one of its unique features. In existing cell therapy, cells from a biopt are cultured for some three weeks. After that, the cells are injected underneath a piece of cell membrane, and the defect is repaired. The cells form cartilage tissue.

In clinical practice, this works, although the cells aren't able to form the desired matrix structures: 'they don't know how to do that'. Jeanine Hendriks therefore investigated the possibilities of stimulating the cells to form a matrix. By mixing cultured cells with primary chrondocytes that haven't been cultured yet, she is able to control the process. By allowing the primary and cultured cells to interact, a matrix will be formed. This is more than creating a more ideal growth environment. It is the cell-to-cell interaction that ‘does the trick', according to Hendriks.

Her results are the starting point for a novel clinical procedure. Hendriks wants to seed the cells on a carrier, a so-called scaffold. This is the same technique that is used in tissue engineering, the main difference is that Hendriks wants to implant the scaffold immediately after seeding and let them grow in vivo, while in tissue engineering, cells usually are cultured in vitro.

The new technique is truly promising: after finishing her PhD work, Jeanine Hendriks wants to further develop the clinical procedures, within her own company CellCoTec.