Abstract: Objective To investigate the role of human Wnt7b gene in rat chondrocyte degeneration. Methods Wnt7b gene
obtained by PCR was cloned to PCDH-GFP. 293ft cell line was transfected with PCDH-GFP and PCDH-Wnt7b, and the
supernatant and transfected cells were collected. The expression level of Wnt7b in 293ft cells was detected by Western blotting.
The first passage of chondrocytes were isolated from articular cartilages of newborn born (within 24 h) SD rats were cultured
in the supernatants from the transfected cells (at 10- and 50-fold dilutions). The cell morphology of the rat chondrocytes was
observed under inverted microscope, and the protein expressions of MMP13, MMP3 and type II collagen and mRNA
expressions of A-can, ADAMTS5, Col X and Sox9 were examined by Western blotting or real-time PCR. Results Human Wnt7b
gene cloned to PCDH-GFP was expressed efficiently in 293ft cell line. Rat chndrocytes cultured for 24 h in the supernatants
from PCDH-Wnt7b-transfected 293ft cells underwent changes from a polygonal to a spindle-shaped morphology. The protein
expression levels of MMP13 and MMP3 increased while type II collagen decreased significantly, and the mRNA levels of A-can
and Sox9 were down-regulated while Col X and ADMATS5 up-regulated in ratchondrocytes after incubation in supernatants
from PCDH-Wnt7b-transfected 293ft cells. Conclusion Human Wnt7b gene can be expressed efficiently in 293ft cell line and
can induce rat chondrocyte degeneration in vitro.