To introduce the CMV promoter driven luciferase and -galactosidase marker gene into previously permeabilized human chondrial cells.

The cultured chondrocyte cells were transfected with a liposome/DNA mixture (pCMV-Luc or pSV40-lacZ). Cultured cells not transfected by liposome/DNA were used as a control. After forty-eight hours of incubation, the cells were used for reporter gene assays and the polymerase chain reaction (PCR).

Fifteen percent of the chondrocyte cells treated with liposome/ pSV40-lacZ DNA were positive for -gal staining. Chondrocyte cells transfected with pCMV-Luc yielded a 70-fold increase in luciferase activity over that of the control cells. A PCR product corresponding to the luciferase gene appeared only in the transfected chondrocyte cells. These results indicate that the human chondrocyte cells can be transfected with pCMV-Luc and pSV40-lacZ.

This system is particularly suitable for gene therapy, as well as for the use of genetically modified cartilage cells for resurfacing full thickness articular cartilage defects.