Immunobiology of cartilage

Kikuchi-Fujimoto disease (histiocytic necrotizing lymphadenitis): report of a case with other autoimmune manifestations

Kikuchi-Fujimoto disease (KFD), or histiocytic necrotizing lymphadenitis, is a benign and self-limited disease that mainly affects young women. Patients present with localized lymphadenopathy, fever, and leukopenia in up to half of the cases. KFD can occur in association with systemic lupus erythematosus. We present the case of a patient with KFD and systemic lupus erythematosus, as well as relapsing polychondritis. This patient had persistently low C4 complement levels, so she was evaluated for a genetic defect in complement production and was found to have two "null" C4 alleles. We believe that this may have contributed to the development of her diseases.

Laryngeal reconstruction using allogeneic cartilages

Preserved allogeneic cartilage has been used to reconstruct laryngeal defects. The most important problem with this approach has been graft resorption, which seems to be caused by devitalization of the grafts as a consequence of preservation. In this study, the authors compared the in vivo behavior of vital and nonvital preserved cartilage used to reconstruct the larynx of New Zealand white rabbits. The vital cartilage grafts were stored using organ culture procedures, and the nonvital grafts were stored in formaldehyde. While the formaldehyde-preserved cartilage showed inflammatory changes, the transplanted vital cartilage was well accepted and showed no evidence of immune cell infiltrations. The authors concluded that viable cartilage grafts are preferable to grafts of chemically preserved cartilage.

Humoral immune response against minor collagens type IX and XI in patients with cartilage graft resorption after reconstructive surgery

OBJECTIVES

The humoral immune response against a broad spectrum of cartilage antigens (cellular and matrix antigens) was studied in a group of patients who showed resorption and/or rejection of transplanted cartilage in nasal surgery.

METHODS

Sera were obtained from patients with successful and unsuccessful cartilage grafting in the nose, from age and sex-matched healthy donors and from patients with rheumatoid arthritis. Antibodies to cartilage components were analysed by the following methods: (1) indirect immunofluorescence on cartilage sections, (2) ELISA using cultured human chondrocytes, isolated chondrocyte membranes and purified collagens type I, II, III, VI, IX and XI, and (3) immunoblotting with purified collagens and chondrocyte cell membranes.

RESULTS

In the cartilage grafting group showing resorption problems, levels of anti-collagen antibodies were significantly higher against native collagen types IX (p < 0.002) and XI (p < 0.002) compared with the non-resorption group and the normal donors. Both transplantation groups revealed elevated reactivities against isolated chondrocytes in the ELISA. In contrast, no reactivity was detectable against collagens type II, III, and VI and chondrocyte cell membranes by both ELISA and immunoblotting.

CONCLUSIONS

These data demonstrate for the first time the existence of a humoral immune response, primarily directed against the so called 'minor cartilage collagens', in patients showing cartilage resorption. Autoreactivities to collagen which are typical of inflammatory rheumatic diseases may also play an important role in the repeated failure of cartilage grafting.

Detection of class II antigens on human nasal cartilage

The presence and distribution of class II antigens on human nasal cartilage was investigated using monoclonal antibodies directed against HLA-DR, HLA-DP, and HLA-DQ molecules. Tissue sections and chondrocytes in suspension were prepared for immunoperoxidase staining and flow cytometric analysis. Class II antigens were detected primarily on the perichondrium. In contrast, chondrocytes, either isolated or in tissue sections, were completely negative, suggesting that cells of the perichondrium, may, by themselves, be capable of initiating a rejection process.

The effect of gamma-interferon on HLA class II antigen expression on isolated human nasal chondrocytes

HLA class II antigens play an important role in the immunological response. In this study, we report on HLA class II antigen expression in vitro by human nasal cartilage cells as detected with an immunoperoxidase staining and immunofluorescence flow cytometric analysis using monoclonal antibodies. Their expression was induced during a 7-day incubation period with gamma-interferon. These findings suggest that a possible mode of action of the preservation methods of cartilage allografts for inducing a prolonged acceptance time is based on the prevention of HLA class II antigen expression by the cartilage cells.

The radiological manifestations of relapsing polychondritis

Four patients with relapsing polychondritis are described. The radiological appearances of the arthropathy and the tracheobronchial involvement are illustrated, and the value of these findings in early diagnosis and management are emphasised.

Evidence that a humoral immune response to autologous cartilage proteoglycan can participate in the induction of cartilage pathology

We examined antiproteoglycan antibodies as an autoimmune response for induction of synovitis. This hypothesis was studied by monitoring humoral antiproteoglycan antibody following IgG induction of experimental immune synovitis, localization in the articular cartilage of an autologous immune response, and loss of proteoglycan from cartilage following intravenous administration of antiproteoglycan monoclonal antibodies. The data support the hypothesis that autoimmunity to cartilage macromolecules may play a role in the etiopathogenesis of arthritis.

Nonsteroidal anti-inflammatory drugs and modulation of cartilaginous changes in osteoarthritis and rheumatoid arthritis. Clinical implications

Nonsteroidal anti-inflammatory drugs have a potential for modifying the complex pathophysiologic events leading to cartilage destruction in various forms of arthritis. Following an evaluation of basic mechanisms in the pathogenesis of cartilaginous destructive lesions, the effects of nonsteroidal anti-inflammatory drugs on normal chondrocyte metabolism are discussed. Their capacity to modulate cartilage and bone lesions in experimental forms of arthritis is addressed, as is the manner in which they may modify the pathophysiology of cartilage destruction in human forms of arthritis. Different classes of nonsteroidal anti-inflammatory drugs produce different effects in certain in vivo or in vitro settings.

Hip joint distension in osteoarthrosis. A triple-blind controlled study comparing the effect of intra-articular indoprofen with placebo

In a triple-blind controlled study, significant pain alleviation (p less than 0.01) was registered in patients with osteoarthrosis (OA) of the hip in the first 24 h after hip joint distension. There was no significant difference between treatment with indoprofen (a new non-steroidal anti-inflammatory drug for intra-articular use) and placebo. Pain relief lasted for at least 12 weeks in approximately half of the patients, in whom a significant increase in joint mobility was registered. Intra-articular indoprofen was not superior to placebo as regards pain relief or increased joint mobility. These findings indicate that the effect of a single hip joint distension in OA is due to a mechanical distension of the joint capsule, perhaps involving disruption of local agglutinations, and not due to suppression of inflammation.

Tissue calcification and inflammation in osteoarthritis

Clinical evidence of inflammation and the presence of calcium phosphate crystals in the joint fluid are both characteristics frequently seen in osteoarthritic patients. However, the relevance of the crystal deposition to the pathogenesis of osteoarthritis remains unclear. In this study of 28 patients with advanced osteoarthritis the frequency and type of crystal deposition has been investigated and the relationship between tissue inflammation and crystal deposition has been explored. Tissue calcification, though present in all patients, is but one of several intra-articular inflammatory agents. Its relevance to inflammation in osteoarthritis is discussed.

Lymphokine-mediated suppression of chondrocyte glycosaminoglycan and protein synthesis

Spontaneously released and T cell mitogen augmented lymphokine produced by human mononuclear cells has been shown to induce a concentration dependent reversible suppression of chondrocyte glycosaminoglycan and protein synthesis without significantly enhancing chondrocyte catabolic activity. The modulatory factor(s) is of T cell origin and is trypsin, pronase, and heat sensitive. Prostaglandin inhibitors failed to influence factor formation or activity. Although eluting from Sephadex G-100 over a wide range, peak activity had an approximate molecular weight of 53,000 and appeared distinct from recognized forms of lymphotoxin.

Histologic assessment of lymphokine-mediated suppression of chondrocyte glycosaminoglycan synthesis

An experimental model has been developed to histologically assess the effect of T cell mitogen-induced lymphokines derived from rabbit splenocytes on proteoglycan matrix depleted auricular cartilage explant glycosaminoglycan synthesis. Explant exposure to lymphokine was shown by light and electron microscopy to significantly suppress chondrocyte glycosaminoglycan regenerative capacity. This inhibitory effect was reversible in that synthetic activity could be restored by placement of explants in control media after as long as 12 days of lymphokine exposure.