Expression of the human chondrocyte phenotype in vitro.
We report a culture scheme in which human epiphyseal chondrocytes lose their differentiated phenotype in monolayer and subsequently reexpress the phenotype in an agarose gel. The scheme is based on a method using rabbit chondrocytes. Culture in monolayer allowed small quantities of cells to be amplified and provided a starting point to study expression of the differentiated human chondrocyte phenotype. The cells cultured in monolayer produced type I procollagen, fibronectin, and small noncartilaginous proteoglycans. Subsequent culture in agarose was associated with the acquisition of typical chondrocyte ultrastructural features and the synthesis of type II collagen and cartilage-specific proteoglycans. The switch from the nonchondrocyte to the differentiated chondrocyte phenotype occurred under these conditions between 1 and 2 wk of agarose culture and was not necessarily homogeneous throughout a culture. This culture technique will facilitate direct investigation of human disorders of cartilage that have been addressed in the past by alternative approaches.
Aulthouse
A L
AL
Department of Pediatrics, University of Texas Medical School, Houston 77225.
Beck
M
M
Griffey
E
E
Sanford
J
J
Arden
K
K
Machado
M A
MA
Horton
W A
WA
D002454:Cell Differentiation; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis; D005353:Fibronectins / Q000096:biosynthesis; D005455:Fluorescent Antibody Technique; D006132:Growth Plate / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D008854:Microscopy, Electron; D010641:Phenotype; D011347:Procollagen / Q000096:biosynthesis; D011509:Proteoglycans / Q000096:biosynthesis; D012685:Sepharose
D005353:Fibronectins; D011347:Procollagen; D011509:Proteoglycans; D003094:Collagen; D012685:Sepharose