Synthesis of a "free" form of hyaluronic acid by articular chondrocytes in monolayer culture.
Primary and first passage rabbit chondrocyte cultures synthesized a "free" form of hyaluronic acid (HA-f) previously characterized in rabbit cartilage. HA-f was isolated from the [3H] glcN/35SO4-labelled cell-associated-fraction (CAF) and from the culture medium by successive equilibrium centrifugations in Cs2SO4/CsCl/Cs2SO4 under low salt conditions. The culture medium HA-f appeared in the void volume of Sepharose CL-2B eluted with low salt, (0.5M sodium acetate), and was susceptible to digestion with Streptomyces hyaluronidase. HA-f aggregated purified rabbit cartilage proteoglycan monomer. These results indicated that HA-f probably subserves hyaluronic acid already complexed with proteoglycan monomer. Newly synthesized HA-f may be required for the continual formation of proteoglycan aggregates.
Malemud
C J
CJ
Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106.
Goldberg
V M
VM
Miller
L M
LM
D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D002478:Cells, Cultured; D002850:Chromatography, Gel; D006820:Hyaluronic Acid / Q000096:biosynthesis*; D011509:Proteoglycans / Q000096:biosynthesis; D011817:Rabbits
D011509:Proteoglycans; D006820:Hyaluronic Acid