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PubMed1992

Type II collagen defect in two sibs with the Goldblatt syndrome, a chondrodysplasia with dentinogenesis imperfecta, and joint laxity.

We report on a syndrome of spondylo-epimetaphyseal dysplasia, dentinogenesis imperfecta, and ligamentous hyperextensibility in two sibs born to nonconsanguineous parents. This chondrodysplasia was characterized by severe shortness of stature and an osteoporosis without fractures. Electron microscopic examination of the cartilage documented large vacuoles of dilated rough endoplasmic reticulum within the cytoplasm of chondrocytes. Gel electrophoresis of pepsin-soluble collagen extracted from cartilage demonstrated the presence of type II collagen chains with an abnormal mobility. Prolyl and lysyl hydroxylations were slightly increased. The abnormal molecules melted at a higher temperature than the normal ones. CNBr peptide mapping of type II collagen showed an altered electrophoretic migration of peptides CB 11, CB 8, and CB 10,5 whereas CB 9,7 looked normal. In addition, two small non-collagenous proteins isolated from cartilage were not found in an age-matched control individual but were detected in a normal newborn infant. The quantitation of proline-labelled collagen synthesized by dermal fibroblasts demonstrated a 50% reduction of total collagen. This decrease essentially affected the amount of extracellular type I collagen, which was secreted less efficiently than in control cells. Nevertheless, type I collagen chains behaved normally on 5% polyacrylamide gels. The reduced mRNA levels of alpha 1I and alpha 2I chains might reflect either a transcriptional defect or a decreased stability of mRNA transcripts. We suggest that the association of both pathological chondrocytes producing altered collagen type II and decreased synthesis of type I could be responsible for this peculiar phenotype. The overmodification of alpha 1II CNBr peptides is consistent with the presence of a single-base substitution in the COL2A1 gene. Whether there is a direct causal relationship between the type II collagen defect and the underexpression of type I collagen will require clarification.

Abnormalities, Multiple↗
PubMed1994

Specificity of antibodies to type II collagen in early rheumatoid arthritis.

OBJECTIVE: To analyze the antibody response to native type II collagen in early rheumatoid arthritis (RA), examining the immunoglobulin isotypes, and polypeptide epitopes recognized, in patients followed over a 2-year period from within 6 months of the first occurrence of symptoms. METHODS: Sera from 16 patients were studied, of whom 10 had antibodies to native type II collagen and 6 did not. The clinical and laboratory assessment, carried out initially and at 6 monthly intervals included the number of 1958 ARA criteria fulfilled, Ritchie index, erythrocyte sedimentation rate, rheumatoid factor and radiological assessment. An ELISA was used to measure IgG, IgA and IgM antibodies, and immunoblotting to identify the number and location of epitopes, using polypeptides prepared by cyanogen bromide digestion of human type II collagen. RESULTS: Antibodies to type II collagen were present in all sequential serum samples for the 10 antibody positive patients. None of the 6 patients who initially lacked antibodies developed them. The antibodies were of IgG isotype in 9, of IgA isotype in 8, and of IgM isotype exclusively in one. At the initial clinical assessment patients with antibodies to collagen were indistinguishable from those without. At 12 and 24 months patients with antibodies fulfilled significantly more ARA criteria than antibody negative patients. The patterns of antibody reactivity to collagen polypeptides by immunoblotting were constant over time but differed from patient to patient. CONCLUSION: The presence of an established and persisting IgG antibody response to type II collagen in early RA before cartilage destruction is evident points to a subset of RA, perhaps equivalent to the collagen induced model in animals, in which this immune response is intrinsic to pathogenesis.

Adult↗
PubMed2002

Crosslinked type II collagen matrices: preparation, characterization, and potential for cartilage engineering.

The limited intrinsic repair capacity of articular cartilage has stimulated continuing efforts to develop tissue engineered analogues. Matrices composed of type II collagen and chondroitin sulfate (CS), the major constituents of hyaline cartilage, may create an appropriate environment for the generation of cartilage-like tissue. In this study, we prepared, characterized, and evaluated type 11 collagen matrices with and without CS. Type II collagen matrices were prepared using purified, pepsin-treated, type II collagen. Techniques applied to prepare type I collagen matrices were found unsuitable for type II collagen. Crosslinking of collagen and covalent attachment of CS was performed using 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide. Porous matrices were prepared by freezing and lyophilization, and their physico-chemical characteristics (degree of crosslinking, denaturing temperature, collagenase-resistance, amount of CS incorporated) established. Matrices were evaluated for their capacity to sustain chondrocyte proliferation and differentiation in vitro. After 7 d of culture, chondrocytes were mainly located at the periphery of the matrices. In contrast to type I collagen, type II collagen supported the distribution of cells throughout the matrix. After 14 d of culture, matrices were surfaced with a cartilagenous-like layer, and occasionally clusters of chondrocytes were present inside the matrix. Chondrocytes proliferated and differentiated as indicated by biochemical analyses, ultrastructural observations, and reverse transcriptase PCR for collagen types I, II and X. No major differences were observed with respect to the presence or absence of CS in the matrices.

Biocompatible Materials↗
PubMed1997

Canine chondrocytes seeded in type I and type II collagen implants investigated in vitro.

Synthetic and natural absorbable polymers have been used as vehicles for implantation of cells into cartilage defects to promote regeneration of the articular joint surface. Implants should provide a pore structure that allows cell adhesion and growth, and not provoke inflammation or toxicity when implanted in vivo. The scaffold should be absorbable and the degradation should match the rate of tissue regeneration. To facilitate cartilage repair the chemical structure and pore architecture of the matrix should allow the seeded cells to maintain the chondrocytic phenotype, characterized by synthesis of cartilage-specific proteins. We investigated the behavior of canine chondrocytes in two spongelike matrices in vitro: a collagen-glycosaminoglycan (GAG) copolymer produced from bovine hide consisting of type I collagen and a porous scaffold made of type II collagen by extraction of porcine cartilage. Canine chondrocytes were seeded on both types of matrices and cultured for 3 h, 7 days, and 14 days. The histology of chondrocyte-seeded implants showed a significantly higher percentage of cells with spherical morphology, consistent with chondrocytic morphology, in the type II sponge at each time point. Pericellular matrix stained for proteoglycans and for type II collagen after 14 days. Biochemical analysis of the cell seeded sponges for GAG and DNA content showed increases with time. At day 14 there was a significantly higher amount of DNA and GAG in the type II matrix. This is the first study that directly compares the behavior of chondrocytes in type I and type II collagen matrices. The type II matrix may be of value as a vehicle for chondrocyte implantation on the basis of the higher percentage of chondrocytes retaining spherical morphology and greater biosynthetic activity that was reflected in the greater increase of GAG content.

Animals↗
PubMed2002

Total abrogation of collagen II-induced arthritis and the B cell response to type II collagen using suboptimal doses of a topoisomerase II antagonist.

BACKGROUND: Collagen-induced arthritis (CIA) is the most commonly used model of rheumatoid arthritis (RA). In both CIA and RA there is an increase in the cellular content of the synovium, this being dominated by macrophages. OBJECTIVE: To assess the impact of etoposide, a topoisomerase II antagonist known to induce monocyte apoptosis, on the development of CIA. METHODS: Mice were primed and booster immunised against collagen II (CII). One group of mice was treated with etoposide two days before CII immunisation and then on four consecutive days weekly until the end of the experiment. The second group of mice was injected with etoposide on four consecutive days a week starting 40 days after CII priming. The third group of mice were controls receiving phosphate buffered saline (PBS). The mice were examined for development of arthritis, numbers of circulating leucocytes, serum CII antibody, and cytokine concentrations. RESULTS: None of the mice given etoposide before CII immunisation developed arthritis. Serum concentrations of anti-CII antibodies were undetectable in these mice, whereas they displayed significantly increased concentrations of interferon gamma and interleukin 6. In addition, the CII specific B cell responses in the draining lymph nodes were highly suppressed. Also, mice treated with etoposide at the onset of clinical arthritis showed reduced frequency of their disease by 50%. CONCLUSION: There was a striking disease alleviating impact of topoisomerase II antagonist on the course of CII-induced arthritis.

Animals↗
PubMed1995

Collagen-induced arthritis in mice: synergistic effect of E. coli lipopolysaccharide bypasses epitope specificity in the induction of arthritis with monoclonal antibodies to type II collagen.

DBA/1 mice develop a chronic peripheral arthritis after immunization with type II collagen termed collagen-induced arthritis. We have localized the main arthritogenic determinants of CB11, a CNBr-generated arthritogenic fragment of chick type II collagen (CII), using 3 smaller peptide fragments of CB11 generated by endoproteinase LysC, LysC1 (CII 124-290), LysC2 (CII 291-374) and LysC3 (CII 375-402) and a panel of monoclonal antibodies (mAb) specific to CB11. MAb specific to the arthritogenic region of CB11 were also used to study the synergistic effect of E. coli lipopolysaccharide (LPS) on antibody-mediated arthritis in naive DBA/1 mice. LysC2 contained a minimum essential arthritogenic fragment of type II collagen: LysC2 induced arthritis by active immunization, also, a combination of four mAb specific to LysC2 passively transferred arthritis to naive mice. A single i.p. injection of LPS (50 micrograms/mouse) reduced the threshold values of the arthritogenic dose of mAb from 1 mg to 50 micrograms/clone per mouse, and decreased the number of mAb required for inducing arthritis from 4 to 2 clones. These observations suggest that LysC2, an 84 amino acid residue fragment, contains the main arthritogenic determinants within chick CB11. Importantly, LPS, a strong inducer of pro-inflammatory cytokines, negates the required multiple epitope specificity of autoantibodies in the passive transfer model and acts synergistically in the induction of arthritis by autoantibody.

Animals↗
PubMed1992

The control of expression of type II collagen: relevance to cartilage disease.

Cartilage is a unique tissue containing only one cell type, the chondrocyte, surrounded by an extensive extracellular matrix. One of the principal components of the cartilage matrix is type II collagen. The gene coding for type II collagen is relatively large and contains several distinct sequences that function to both up-regulate and down-regulate expression by interacting with chondrocyte transcription factors. Also, there appears to be regulation of collagen II expression by differential splicing of the collagen II mRNA to form different forms of the protein. Finally, the gene is a target for mutations that result in diseases of cartilage such as chondrodysplasias and some forms of osteoarthritis.

Animals↗
PubMed1991

Identification of genes associated with tumor suppression in Syrian hamster embryo cells.

Loss of a tumor-suppressor gene function appears to play a critical role in the multistep process of neoplastic transformation of Syrian hamster embryo (SHE) cells in vitro. Clonal variants of two independent, preneoplastic cell lines have been isolated that have either retained (termed supB+) or lost (termed supB-) the ability to suppress the tumorigenicity of a highly malignant benzo[alpha]pyrene-transformed SHE cell line (BP6T) in cell hybrids. We have pursued several approaches in an attempt to identify genes that are responsible for tumor suppression in these cells. The only consistent differences detected in two-dimensional gel analyses of supB+ and supB- cellular proteins were decreases in the levels of two high molecular weight isoforms of tropomyosin in supB- cells. Differential screening of a supB+ cDNA library for genes that are preferentially expressed in supB+ cells yielded cDNA clones for four genes, i.e., collagen type II, collagen type IX, H19, and a previously unidentified gene (clone 5). Nuclear run-on assays suggested that higher transcription rates were responsible for the increased steady-state levels of some of these transcripts in supB+ cells. DNA sequence comparisons showed that two copies of a 9 bp element, previously identified in each of the mouse H19 enhancers, were also present in the 5' flanking region of the rat type II collagen gene. A transcription factor that controls expression of the collagen and H19 genes through binding to this conserved motif would be an attractive candidate for the supB+ gene or at least a mediator of the supB+ phenotype.

Animals↗
PubMed1986

High antibody response to autologous type II collagen is restricted to H-2q.

The incidence of arthritis and the antibody response to mouse and to rat type II collagen after immunization with native rat type II collagen was studied in different mouse strains, including wild mouse-derived strains belonging to the H-2p/H-2q family. High serum levels of antibodies to mouse and rat type II collagen were seen only in H-2q mice, whereas mice belonging to the p, w3, w5, and w17 haplotypes displayed low type II collagen-specific antibody responses. Mice from three different H-2q-carrying strains (DBA/1, NFR/N, and B10.G) with different non-major histocompatibility complex genes were all susceptible to collagen arthritis, but they displayed a varying incidence of arthritis and varying clinical features. No arthritis was seen in non-H-2q mice, except in the B10.CAS2 strain where a few mice developed arthritis despite very low serum levels of type II collagen-specific antibodies. We conclude that small differences in the A beta chain of class II transplantation antigens are of importance for the development of arthritis and for the stimulation of a high response after immunization with type II collagen.

Animals↗
PubMed1983

Type II collagen from lathyritic rat chondrosarcoma: preparation and in vitro fibril formation.

Intact type II collagen monomer was isolated in 10-20% yield from lathyritic rat chondrosarcoma and purified to homogeneity. On warming in neutral solution, the collagen formed a mixture of D-periodic native fibrils and thin filaments with no apparent structure. There were characteristic lag and growth phases in the turbidity profile. cooling dispersed or dissolved the fibrils leaving thin filaments. The fibrils were very wide, up to 2.0 micrometers compared to the 10 to 40 nm fibrils present in situ. They had the appearance of stiff tactoids compared to the very long and flexible fibrils obtained from type I collagen under similar conditions. Type II collagen also required higher temperatures and concentrations than type I to form fibrils. The continued presence of thin filaments when type II fibril formation was complete suggests either that filaments are in slow equilibrium with fibrils or that they may not be intermediates but rather a separate product.

Animals↗
PubMed1999

Differential detection of type II collagen N-terminal and C-terminal denaturation epitopes in degrading cartilage.

AIMS: To investigate the relative stability of collagen metabolites in degrading cartilage. METHODS: New antipeptide antibodies to denaturation epitopes located in the N-terminal and C-terminal regions of the type II collagen helix have been made and characterized. Type II collagen fragments in the conditioned medium from cultures of degrading bovine nasal cartilage were detected by immunoblotting with the new antisera as well as by N-terminal sequencing. The antibodies were also used in immunohistochemical studies of normal and osteoarthritic human cartilage. RESULTS: Type II collagen fragments with an apparent molecular mass of approximately 30 kDa were detected in cartilage conditioned media using antibody AH12L3, which recognizes N-terminal epitope AH12. The N-terminal sequence of one of these fragments matched exactly a sequence in the N-terminal region of type II collagen. Antibody AH9L2, which recognizes C-terminal epitope AH9, did not bind to any protein bands in the immunoblotted culture medium. In immunohistochemical studies, antibody AH12L3 detected extensive regions of degraded collagen in osteoarthritic cartilage and a more restricted pattern of staining in nonarthritic cartilage. Far less immunostaining was apparent in all cartilage specimens with antibody AH9L2. CONCLUSIONS: These results indicate that the N-terminal region of type II collagen is more resistant to proteolysis than the C-terminal region, an observation that has important implications for the choice of epitopes that are likely to be good markers of damage to cartilage collagen in patients with arthritis.

Antibody Specificity↗
PubMed2002

Immunization of rats with homologous type XI collagen leads to chronic and relapsing arthritis with different genetics and joint pathology than arthritis induced with homologous type II collagen.

The most commonly used animal model for rheumatoid arthritis (RA) is collagen-induced arthritis (CIA), induced by immunization with type II collagen (CII), a cartilage restricted protein. In this work we show that type XI collagen (CXI), which is a minor component in cartilage, induces a different form of erosive and chronic relapsing polyarthritis in rats. Using a series of inbred rat strains involving various genetic backgrounds (DA, LEW, E3), and congenic MHC regions (a, u, f, n, c, d), we found that CXI induced arthritis (C(XI)IA) is associated with the RT1f haplotype in contrast to CII induced arthritis (C(II)IA), which is associated with the RT1a and RT1u haplotypes. The C(XI)IA follows a chronic disease course affecting peripheral joints with both progression and relapses, which appear not to cease (occurring >800 days). Susceptible strains showed a sustained antibody response to CXI with time indicating that the autoimmune response was self-perpetuated. Microscopic analysis of the joints at different stages demonstrated the severe destruction of bone and cartilage by pannus tissue consisting of activated macrophages and T cells. The main difference to joints from rats with C(II)IA was larger numbers of infiltrating lymphocytes and these tended to form follicle-like aggregates. Surprisingly, males were more susceptible to C(XI)IA than females whereas the opposite has been observed in other rat arthritis models, including C(II)IA. Taken together, C(XI)IA is a chronic relapsing and erosive polyarthritis that is MHC associated, which in fact fulfills the criteria for diagnosis of RA. Thus the C(XI)IA model will be useful as a novel and relevant animal model for RA.

Animals↗
PubMedDate not supplied

The role of type II collagen autoimmunity in otosclerosis revisited.

A recent theory, suggesting that otosclerosis results from autoreactivity to type II collagen present in the fetal cartilaginous remnants of the human bony labyrinth, is based on two observations. Otosclerotic patients have increased concentrations of circulating antibody to type II collagen, and immunization of rodents with cartilage collagen induces 'otosclerosis-like' lesions. Independent researchers have been unable to confirm the first promising results. No significant abnormalities could be found in immunized animals. We report the result of type II collagen antibody recordings in a well described group of otosclerotic patients and controls, and the histological findings in temporal bones of MRL/1-mice with spontaneous type II collagen autoreactivity. Our results cannot support the view of autoreactivity to type II collagen as an etiopathogenetic factor in otosclerosis.

Adolescent↗
PubMed1989

Pattern of humoral reactivity to type II collagen in rheumatoid arthritis.

Humoral immunity directed against type II collagen (CII) is a common although not specific feature of rheumatoid arthritis (RA). We have shown that 10 to 15% of the sera either from RA patients (n = 88) or from healthy controls (n = 149) reacted with native human CII. Conversely, autoantibodies to the alpha-1 (II) chains were significantly more frequent in the RA group (26.1% versus 6.0%, P<0.001), suggestingthatdenaturedCII may bean autoantigenin RA. Thus, human CII was cleaved with cyanogen bromide (CB), and immunoblotting techniques were performed on 19 RA and 21 normal sera. Among the four major CB peptides, CB10 and CB11 were recognized by most of the sera tested without distinction between normal or RA sera. Inhibition experiments using an ELISA have shown that: (i) antibodies to the native CII molecule did not cross-react with those recognizing the CB peptides, and vice-versa; (ii) the binding of the sera to native CII was partially inhibited by pre-incubation with alpha-1 (II) chains, and vice-versa; (iii) pre-incubation of the sera with CB peptides partially blocked the binding to alpha-1 (II) chains, whereas pre-incubation of the sera with alpha-1 (II) chains totally inhibited the reactivity against CB peptides; and (iv) a substantial proportion of the epitopes recognized by anti-CII autoantibodies was neither species specific nor type specific. Taken together, these findings reveal the existence of several populations of anti-CII autoantibodies: some antibodies react exclusively with conformational determinants of the CII molecule, and others are directed towards linear structures of alpha-1 (II) chains.

Animals↗
PubMed1998

Correlation between IgG anti-type II collagen levels and arthritic severity in murine arthritis.

This study examines the relationship between the serum levels of IgG antibodies to heterologous and homologous type II collagen and the subsequent arthritic severity in a collagen induced arthritis model. Arthritis was induced in DBA-1 mice using intradermal injections of heterologous type II collagen in Freunds complete adjuvant, the time of arthritis onset was noted and the severity was monitored regularly. Serum samples were taken and IgG levels of anti-heterologous and homologous type II collagen were analyzed both pre and post arthritis onset. We observed that post induction/pre arthritic serum IgG anti-heterologous and homologous type II collagen levels showed a significant correlation (both p < 0.01) with the severity of the arthritis that subsequently developed. Mice with early arthritis showed a highly significant correlation (p < 0.002) between sera IgG anti-homologous type II collagen levels and arthritic severity, a lesser correlation was also apparent between anti-heterologous type II collagen titres and arthritic severity (p < 0.05). The high levels of correlation observed in this study between anti-type II collagen titres and arthritic severity before actual onset of arthritis, clearly suggest that the magnitude of the initial humoral response to type II collagen plays a crucial role in determining the resultant arthritic severity. This observation is only apparent due to the use of an arthritis susceptible inbred mouse strain, which removes variables such as H-2 restriction, antigen processing/presentation and possible complement deficiencies, and the early time scale of the analysed sera samples.

Animals↗
PubMed1999

In situ zymographic localisation of type II collagen degrading activity in osteoarthritic human articular cartilage.

OBJECTIVES: Chondrocytic matrix metalloproteinases (MMPs) are believed to be important in osteoarthritic cartilage degradation. The cartilage lesion of osteoarthritis (OA) is focal and often progressive. During its development chondrocytes differentially up and down regulate production of mRNA for individual MMPs. This observation has potential implications for understanding the disease processes that lead to progressive cartilage loss in OA and designing appropriate targeted treatment. The complex regulation of MMP mediated effects means there is a pressing need to establish whether visualisation of MMP mRNA or protein equates to enzyme activity. The technique of in situ zymography (ISZ) offers a way of examining diseased human tissue for in vivo production of an excess of degrading enzyme over inhibitor. The primary objective of this study was to assess, and if positive follow, collagen II degrading activity in cartilage during development of the OA lesion. A secondary objective was to assess whether there was any correlation between sites of collagen II degrading activity and expression of the collagenase (MMP-13), recently implicated in type II collagen degredation in this lesion. METHODS: Biopsied human normal and osteoarthritic cartilage, showing various degrees of damage, was examined by in situ zymography, with and without enzyme inhibitors, to establish sites of type II collagenase activity. Paired samples were probed for MMP-13 mRNA using 35S-labelled oligonucleotide probes. Comparative analyses were performed. RESULTS: In situ zymography showed collagen II degrading activity over chondrocytes only in osteoarthritic cartilage. Distribution and amount varied with the extent of cartilage damage and position of chondrocytes, being greatest in deep cartilage and in cartilage lesions where fissuring was occurring. The enzyme causing the degradation behaved as a matrix metalloproteinase. MMP-13 mRNA expression codistributed with the type II collagenase activity. CONCLUSION: In OA, chondrocytes can degrade type II collagen. The type II collagen degrading activity varies in site and amount as the cartilage lesion progresses and throughout codistributes with MMP-13 mRNA expression.

Adult↗
PubMed1982

Assessment of drugs for activity in established type II collagen arthritis.

Arthritis was induced in a proportion of rats sensitized with type II collagen and Freund's incomplete adjuvant. Rats which developed arthritis had significantly higher antibody titres and significantly greater delayed hypersensitivity responses to type II collagen than rats which did not develop arthritis. Anti-inflammatory and anti-rheumatic drugs were evaluated against type II collagen arthritis. Dexamethasone reduced inflammatory swelling, reduced both the antibody titre and delayed hypersensitivity to type II collagen and exerted joint protection. Indomethacin reduced inflammatory swelling. Azathioprine, Clozic, Levamisole, D-Penicilamine and Sulphapyridine did not exert significant beneficial activity in this test.

Animals↗
PubMed1986

Murine T cells reactive to type II collagen. II. Functional characterization.

DBA/1 mice immunized with native chick type II collagen (NcII) emulsified in complete Freund's adjuvant develop arthritis, whose underlying mechanisms are still undefined. As an initial step to studying the role of T cells in collagen-induced arthritis (CIA), we have established T cell lines specific to type II collagen. Characterizations of the antigen-induced proliferative responses mediated by these T cells have been reported. In essence, two major populations of collagen-reactive T cells were isolated: those that responded mainly to denatured type II collagen (DcII) and another group that reacted with both DcII and NcII. As shown in the present study, all of the collagen-reactive T cell lines isolated were found to be functional, although they differed in their capacity to mediate helper activities assessed by different assays. Hence, both populations of T cells exhibited the ability to trigger B cell proliferation, whereas only the population that recognized both DcII and NcII was capable of activating the synthesis of immunoglobulins by B cells. T cells from this latter group also provided specific help for the generation of a secondary anti-DNP antibody response. In addition, these T cells were capable of activating NcII-specific B cells to produce anti-collagen antibodies. By contrast, the T cell lines that reacted exclusively to DcII failed to mediate such specific helper functions. The inability of such T cells to activate DNP-primed B cells upon challenge with DNP-DcII did not appear to be due to a modification of antigenic sites on DcII by haptenation. Inasmuch as the DcII-specific T cell lines also proliferate less well in response to DcII than the T cell lines that recognize both DcII and NcII, a difference in the nature of the antigen receptors expressed by the two populations of collagen-specific T cells may partly explain the above observations. However, the inability to generate appropriate factors required for further differentiation of B cells to produce antibodies may also account for the failure of DcII-specific T cells to activate DNP-primed B cells. Finally, both populations of T cells were capable of mediating specific delayed-type hypersensitivity response.

Animals↗