Characterization of newly synthesized proteoglycans from rabbit menisci in organ culture.

Rabbit menisci were incubated with Na2 35SO4 in short-term organ culture to label newly synthesized proteoglycans. The radioactive products present in both tissue and culture medium were characterized separately with respect to distribution after ultracentrifugation in CsCl isopycnic density gradients, hydrodynamic size, interaction with hyaluronic acid, and glycosaminoglycan composition (types, size and content). Analysis of proteoglycan size by gel-filtration chromatography of the most-dense CsCl fractions (A1) on Sephacryl S-500 (associative conditions) resolved three species.

Correlation of histopathology and sulfated proteoglycans in human osteoarthritic hip cartilage.

The histopathologic characteristics, in vitro proteoglycan and glycosaminoglycan biosynthesis, and proteoglycan content of osteoarthritic (OA) cartilage tissue types from human femoral heads obtained at the time of total joint replacement were compared. Articular cartilage from fibrillated or discolored cartilage surfaces demonstrated overlapping histopathologic patterns, while cartilage from osteophytic areas was distinct. 35SO4 from each of these three tissue types was found in two peaks of radioactivity on a Sepharose CL-2B column.

'Gelatinase-like' activity from articular chondrocytes in monolayer culture.

In addition to releasing collagenase and proteoglycanase activity, rabbit articular chondrocytes in monolayer culture released into the culture medium, latent, neutral enzyme activity which when activated by p-aminophenylmercuric acetate degraded fluorescein-labeled polymeric rat tail tendon Type I collagen and the tropocollagen TCA and TCB fragments of human Type II collagen into smaller peptides at 37 degrees C. Enzyme activity was abolished if p-aminophenylmercuric acetate-activated culture medium was preincubated with 1.10-phenanthroline, a metal chelator.

Biosynthesis of proteoglycan in vitro by cartilage from human osteochondrophytic spurs.

Proteoglycan biosynthesis by human osteochondrophytic spurs (osteophytes) obtained from osteoarthritic femoral heads at the time of surgical joint replacement was studied under defined culture conditions in vitro. Osteophytes were primarily present in two anatomic locations, marginal and epi-articular. Minced tissue slices were incubated in the presence of [(35)S]sulphate or [(14)C]glucosamine.

Neutral proteinases from articular chondrocytes in culture. 2. Metal-dependent latent neutral proteoglycanase, and inhibitory activity.

Monolayer and spinner cultured rabbit articular chondrocytes released into the medium latent metal-dependent enzyme with activity against bovine proteoglycan. Pretreatment of medium with p-aminophenylmercuric acetate or trypsin followed by soybean trypsin inhibitor significantly increased enzyme activity. The monolayer-cultured chondrocytes released more of this activity than spinner cultures.

Neutral proteinases from articular chondrocytes in culture. I. A latent collagenase that degrades human cartilage type II collagen.

Culture media collected from secondary monolayer and spinner cultures of rabbit articular chondrocytes showed evidence of collagenolytic activity by the following criteria: (1) Amicon PM-10 concentrates of culture medium released [14C] glycine from reconstituted rabbit skin collagen fibrils at 37 degrees C; (2) medium concentrated by lyophilization decreased the relative viscosity of human cartilage collagen in solution. The loss in viscosity was partially inhibited if medium was preincubated with o-phenanthroline, and (3) degradation of human cartilage collagen after 60 h incubation at 24 degrees C was characterized primarily by the appearance of 75 000 dalton (TCA) and 25 000 dalton ((TCB) products. The majority of the collagenase (EC 3.

Partial purification and characterization of mouse peritoneal exudative macrophage elastase.

Mouse peritoneal exudate macrophage elastase can be significantly purified with 60% recovery of the starting activity by affinity chromatography against SDS-treated alpha-elastin covalently linked to agarose beads. The enzyme has an apparent Mr of 26 500 based on SDS-acrylamide gel electrophoresis. Molecular sieving chromatography on Sephadex gel gives a Mr for macrophage elastase of 21 000--28 000.

Metal-dependent neutral proteoglycanase activity from monolayer-cultured lapine articular chondrocytes.

Neutral proteoglycanase and other protease activity from cellular and CM fractions of monolayer-cultured rabbit articular chondrocytes were studied. The cellular fraction comprising soluble cytoplasmic enzymes possessed concentration-dependent elastase-like esterase activity and activity against trypsin and chymotrypsin synthetic substrates but had little caseinase activity. The 20% ammonium sulfate precipitate of CM possessed more neutral caseinase activity than the 60% ammonium sulfate precipitate and the bulk of activity against the synthetic substrates.

Explant culture of human and rabbit articular chondrocytes.

Copious outgrowth of chondrocytes was obtained by explantation from each of three rabbit and one surgically-resected human articular cartilages pretreated briefly with trypsin. In lapine explants, ascorbate (40 micrograms/ml) increased DNA three-fold over control values and resulted in deposition of a chondroid matrix. It doubled radiosulfate incorporation by the outgrowths.

Differences in the collagen types synthesized by lapine articular chondrocytes in spinner and monolayer culture.

In five different secondary monolayer cultures of rabbit articular chondrocytes, 72-89% of the the collagen synthesized was Type 1, as determined by alpha chain separation and CNBr-cleavage peptide analysis. When sister cells were transferred to spinner bottles after primary monolayer culture growth, 88% of the collagen formed in four separate experiments was Type II. A reversion to Type I collagen synthesis occurred when the spinner-cultured cells were returned to monolayer flasks.

Autosomal phosphogluconic dehydrogenase polymorphism in the cat (Felis catus L.).

Three patterns of 6-phosphogluconic dehydrogenase activity were obtained by starch-gel electrophoresis of blood from domestic cats. Genetic analysis indicates control of these patterns by a pair of alleles at an autosomal locus. Presence of three enzymatically active bands in heterozygotes and of single bands in homozygotes is compatible with at least a dimeric structure for the enzyme.

Spontaneous occurrence of chromosome abnormality in cats.

A syndrome in male cats analogous to chromatin-positive Klinefelter's syndrome in human males has been demonstrated. The physical characteristics which suggested an abnormality of chromosome number in cats were "calico" or "tortoise-shell" coat colors in a male. Buccal mucosal smears were found to have "female-type" patterns in two out of 12 such male cats screened, and these two were found to have a diploid chromosome number of 39 rather than the normal 38.