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H Stöss

Publications and source records attributed to H Stöss.

At least 37 records · Page 2Linked to original sources
PubMed1993

Preferential cellular and humoral immune reactivities to native and denatured collagen types IX and XI in a patient with fatal relapsing polychondritis.

We describe a patient with histologically confirmed relapsing polychondritis, an episodic systemic disorder. Although the etiology is unknown and its pathogenesis is incompletely understood, there is evidence strongly suggesting immunologically mediated mechanisms. Enzyme linked immunosorbent assays, immunoblotting and cellular immune responses using lymphocyte proliferation assays showed strong parallel humoral and cellular immune reactivities against collagens type IX and XI. There was also a considerable response to collagen type II which, however, was less pronounced compared to collagen type IX and was directed to native epitopes. Our findings demonstrate a highly distinct immune response to minor matrix collagens in a destructive cartilage disease and thus strongly argue against nonspecific anticollagen immune reactions simply representing epiphenomena resulting from cartilage damage.

Aged↗
PubMed1992

Type X collagen synthesis in human osteoarthritic cartilage. Indication of chondrocyte hypertrophy.

OBJECTIVE: To investigate the appearance of hypertrophic chondrocytes in osteoarthritic (OA) cartilage, using type X collagen as a specific marker. METHODS: The biosynthesis of type X collagen was examined by metabolic labeling of freshly isolated articular chondrocytes with 3H-proline, immunoprecipitation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the synthesized collagens. Extracellular deposition of types X and II collagen was analyzed immunohistochemically. RESULTS: Immunostaining revealed an irregular distribution of type X collagen, which was localized around chondrocyte clusters in fibrillated OA cartilage, but was absent from the noncalcified region of normal articular cartilage. Freshly isolated OA chondrocytes synthesized predominantly type X collagen, while control chondrocytes synthesized mostly type II collagen. CONCLUSION: Our findings indicate focal premature chondrocyte differentiation to hypertrophic cells in OA cartilage.

Adult↗
PubMed1992

Activation of collagen type II expression in osteoarthritic and rheumatoid cartilage.

In situ hybridization and immunohistochemical techniques were applied to investigate gene expression and extracellular deposition of collagen type II in normal, osteoarthritic and rheumatoid human articular cartilage. Normal cartilage showed an essentially even extracellular distribution of type II collagen with poly- and monoclonal antibodies, while only a few cells were positive for alpha 1(II) collagen mRNA. In situ hybridization of osteoarthritic and rheumatoid cartilage, however, showed strong enhancement of type II collagen gene expression; transcripts were observed predominantly in the upper middle zone of the articular cartilage while the upper layer was mostly negative and correlated with a zone of reduced proteoglycan staining. The elevated mRNA levels frequently coincided with pericellular immunostaining for type II collagen, indicative for enhanced synthesis of the protein. In two samples, however, pericellular loss of collagen type II staining was found despite positive cytoplasmic signals with the alpha 1(II) RNA probe, suggesting enhanced collagen destruction. Control hybridization with a probe for 18S rRNA revealed very few negative cells throughout both normal and arthritic cartilage samples, ruling out major cell necrosis in the specimens investigated. Thus, our observations identify sites of activated type II collagen synthesis in osteoarthritic cartilage that were predicted by previous biochemical studies and support the notion that damaged cartilage attempts to restore matrix by enhanced synthesis of its components.

Adolescent↗