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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the effects of interleukin (IL)-1β on matrix synthesis and degradation by chondrocytes cultured in a 3-dimensional (3-D) gel medium.

Sample Population—Chondrocytes from 7 dogs.

Procedure—Articular chondrocytes were harvested and cultured in 3-D gel medium alone or with 10 or 20 ng IL-1βml that was added beginning on day 0, 3, 6, or 9. On days 3, 6, 12, and 20 of 3-D culture, samples of the liquid medium were evaluated for glycosaminoglycan (GAG), prostaglandin E2 (PGE2), and matrix metalloprotease (MMP)-3 content. The 3-D plug in each well was evaluated for histologic characteristics of viability, cell morphology, and proteoglycan staining, immunohistochemically stained for collagen type II, and spectrophotometrically analyzed for GAG content.

Results—Significant differences for all variables were detected between controls and each IL-1β group, among groups with different IL-1β concentrations, and among groups with IL-1β added at various time points. Chondrocytes exposed to IL-1β had loss of GAG, increased PGE2 and MMP-3 concentrations, and lack of collagen type-II synthesis. These IL-1β effects appeared to be time and concentration dependent.

Conclusions—Addition of IL-1β to chondrocytes in 3- D gel medium results in time- and concentrationdependent effects on matrix synthesis and degradation and provides an appropriate in vitro model for many of the pathophysiologic events associated with osteoarthritis. (Am J Vet Res 2000;61:766–770)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To characterize chondrocytes from naturally occurring osteochondrosis (OC) lesions of the humeral head of dogs.

Sample Population—15 cartilage specimens from 13 client-owned dogs with humeral head OC and 10 specimens from the humeral head of healthy dogs (controls).

Procedure—Chondrocytes were isolated and cultured in a 3-dimensional system. On days 7, 10, 15, 20, and 25, glycosaminoglycan and hydroxyproline content and cytologic characteristics were evaluated. Expression of collagen types I, II, and X was assessed by use of immunohistochemistry.

Results—Chondrocytes from OC lesions were less viable, compared with control chondrocytes. Glycosaminoglycan content in the OC group was significantly less than in the control group on all days except day 20. Hydroxyproline content was also significantly less in the OC group on days 10, 20, and 25. Expression of collagen type II was significantly less in the OC group, compared with the control group on all days, whereas expression of collagen type I was significantly greater in the OC group on days 20 and 25. Expression of collagen type X was significantly less in the OC group on all days except day 25.

Conclusions and Clinical Relevance—Chondrocytes from naturally occurring OC lesions of the humeral head of dogs cultured in a 3-dimensional system were less viable and less capable of producing appropriate extracellular matrix molecules than chondrocytes from unaffected dogs. Alterations in the synthetic capabilities of chondrocytes from OC-affected cartilage may be a cause or an effect of the disease process. (Am J Vet Res 2002;63:186–193)

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in American Journal of Veterinary Research

Abstract

Objective

To determine the effects of transplantable substrates on canine chondrocytes grown in three-dimensional culture.

Animals

3 canine cadavers.

Procedure

Articular cartilage harvested from canine cadavers was used to obtain chondrocytes for primary culture. Subcultured chondrocytes were grown in agarose alone (AG), or in agarose on canine cancellous bone (CB), polypropylene mesh, or oxidized regenerated cellulose substrate. Cell proliferation, proteoglycan and glycosaminoglycan (GAG) production, and collagen production were assessed on days 3, 6, 10, 15 and 20.

Results

Chondrocytes from groups AG and CB proliferated and produced matrix over the entire 20-day study period. Group-CB chondrocytes had significantly more GAG than did chondrocytes of all other groups on days 6 (P = 0.0297) and 15 (P = 0.00272). Those of groups AG and CB contained significantly (P = 0.0235) more GAG on day 20. Chondrocytes of the polypropylene mesh group proliferated and produced matrix through day 10 in culture, but were no longer viable and had no matrix production on days 15 and 20. Regenerated cellulose appeared to be toxic to canine chondrocytes during all stages of in vitro three-dimensional culture.

Conclusions

Three-dimensional culture of canine chondrocytes in agarose appears to produce favorable results with respect to chondrocyte proliferation and matrix production. Canine CB appears to have beneficial effects with regard to early GAG synthesis. Polypropylene mesh and oxidized regenerated cellulose had detrimental effects on cellular proliferation and matrix production. (Am J Vet Res 1997;58:419–424)

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in American Journal of Veterinary Research