Antibodies to endothelial cells in patients with Behçet's disease

Autoantibodies that bind to endothelial cells have been identified in patients with several forms of vasculitis. Behçet's disease--a multisystem inflammatory disorder of unknown etiology--is associated with thrombosis in addition to systemic manifestations resulting from small and large vessel vasculitis. We studied 72 Turkish patients (33 female, 39 male) with Behçet's disease in order to investigate the prevalence of antiendothelial cell antibodies (AECA) and to examine their possible relationship with clinical and laboratory features of the illness. Sera from 30 healthy Turkish people were used as controls. Human umbilical vein endothelial cells were cultured and used unfixed in a cellular ELISA to detect AECA. IgG and/or IgM AECA were found in 13 (18.1%) patients but not in healthy controls. Antiendothelial cell antibodies did not induce complement-mediated cytotoxicity as assessed by 51Cr release assay and the binding was not due to immune complexes. The prevalences of acute thrombotic events and retinal vasculitis at the time of the AECA assay among patients with AECA were significantly higher than those in patients without AECA. Laboratory parameters of active disease were higher in patients with AECA. There was no correlation between other clinical and laboratory features of Behçet's disease and AECA. Anticardiolipin and antineutrophil cytoplasmic antibodies were negative in our series, excluding a possibility of cross-reaction with AECA. Our results suggest a possible role of AECA in association with thrombosis and vasculitis in patients with Behçet's disease.

[A ciclosporin A responsive case of Behçet's disease associated with IgA nephropathy]

A case of Behçet's disease with IgA nephropathy was reported in a 17 year old man. He presented with microscopic hematuria which was pointed out by urinary mass screening for school children at age of 14. As he was subsequently evolved proteinuria, a renal biopsy was performed at age of 16. The specimen showed diffuse proliferation of mesangial cells. Immunofluorescent studies showed granular deposition of IgA. At age of 17, he showed typical symptoms of Behçet's disease, namely aphthous stomatitis, perianal ulcers, erythema nodosum-like lesions, uveitis and genital aphtha. Furthermore he showed an increasing of proteinuria and an impairment of his renal function. Serum IgA level and immune complexes during the exacerbation stage were elevated. The uveitis markedly improved with ciclosporin A therapy. Reduction of proteinuria and improvement of renal function were simultaneously observed. These findings may suggest that IgA nephropathy and Behçet's a disease have common immunological pathogenesis, including circulating immune complexes.

Miscellaneous vasculitic syndromes including Behçet's disease and central nervous system vasculitis

Behçet's disease is a chronic, relapsing, inflammatory process with clinical features of aphthous oral and genital ulcerations, uveitis, cutaneous vasculitis, arthritis, and central nervous system involvement. Large-vessel vasculitis, thrombophlebitis, and gastro-intestinal ulcerations may occur. As in other rheumatologic diseases, a genetic predisposition coupled with a triggering event leads to alterations in immune function and response, with variable clinical disease manifestations. Mononuclear cell activation and cytokine release, neutrophil chemotaxis, and humoral immune response with elevations of circulating immune complexes contribute to the pathogenesis of Behçet's disease. Vasculitis and vascular involvement are highlighted. There is no single diagnostic test for Behçet's disease. Treatment is comprised of anti-inflammatory and immunosuppressive agents and, in selected individuals, anticoagulation. Isolated central nervous system vasculitis or noninfectious primary (granulomatous) angiitis of the central nervous system is reviewed briefly. This condition is rare, predominantly affects young women, and includes symptoms of headache, weakness, and confusion. Characteristically, erythrocyte sedimentation rate is normal, serologic studies are negative, and cerebral angiography shows multifocal and segmental vascular narrowing and beading. Typical histopathology is granulomatous in less than 50% of patients, followed by necrotizing or lymphocytic vasculitis, or both, often with thrombosis. Treatment with immunosuppressive agents improves symptoms and outcome.

[Type I herpes virus, HLA phenotype and Behçet disease]

BACKGROUND

The pathogenic factors of Behçet's disease (BD) differentiate according to geographical zones. The aim of this study was to evaluate the possible relation between this process and infection by type I herpes simplex virus (HSV-1) in Spain.

METHODS

The prevalence of antibodies vs HSV-1 and cytomegalovirus (CMV) was studied by complement fixation in three series: A) 34 patients with BD; B) 21 with primary uveitis; C) 40 controls. HSV-1 specificity was established by ELISA. HLA typing was performed in 32 individuals from series A.

RESULTS

The frequency of anti HSV-1 in A (76%) was greater (p = 0.045) than in C (55%) and B (66%). These differences were more evident when titers equal/superior to 1/64 were considered as positive, with this being a value exceeding the 97.5% percentage of the control series (A = 21%, C = 2%, p = 0.015), specially for the ocular BD subgroup (26%, p = 0.011 with respect to C). The B series did not differ from C (p = 0.88). To the contrary no differences were observed in the distribution of titers vs CMV. Although a greater frequency of anti HSV-1 was observed in HLA-B51+ the differences were not significant (p = 0.09).

CONCLUSIONS

The frequency of evaluable titers of anti-HSV-1 is greater in patients with BD (specially with ocular involvement) than in the control series. No association was found between higher titers and HLA PB51+ phenotype.

[Hemolytic anemia complicated with Behçet's disease and myelodysplastic syndrome]

A rare case of hemolytic anemia complicated with Behçet's disease and myelodysplastic syndrome (MDS) is described. A 41-year old woman suffering from hemolytic anemia was admitted in July of 1988 with right lower abdominal pain and a high fever. Her anemia was first pointed out in 1962 (at age 15), and diagnosed as hemolytic anemia in 1977 by a full hematological examination showing erythro-hyperplasia in bone marrow, Coomb's test was negative and corticosteroid therapy failed to improve her anemia. She had also been suffering from recurrent stomatitis and genital ulcer since the delivery of her first baby in July, 1972. Barium enema was performed and revealed a simple deep ulcer at the terminal ileum. Bone marrow examination showed morphological abnormalities of granulocytic and erythrocytic series. We thereby diagnosed her illness as incomplete Behçet's disease and MDS associated with hemolytic anemia. She was treated by ubenimex, blood transfusion and intravenous alimentation with discontinuing oral intake, and there was a satisfactory improvement in pancytopenia and ulcer.

Treatment of Behçet's disease

Behçet's disease is a systemic inflammatory disorder capable of inducing thrombophlebitis. Clinicopathologically, it is characterized by neutrophil and platelet hyperfunction. Lesions are formed presumably because neutrophils infiltrating the affected tissue release active oxygen and lysosomal enzymes in large amounts. The mechanism of neutrophil hyperfunction was obscure, but in recent years attention has focused on the effects of cytokines released by mononuclear cells. As more has been learned about the etiopathogenesis of Behçet's disease, novel anti-inflammatory drugs, immunosuppressants, anti-thrombotic agents, and anticoagulants have helped to achieve remarkable progress in treatment. Particularly notable is the effect on severe uveitis of cyclosporine, which is more effective than colchicine and conventional immunosuppressants. With the advent of cyclosporine, the number of patients with Behçet's disease who lose their eyesight has clearly decreased.

HLA B51 antigen associated with neutrophil hyper-reactivity

HLA B51 specificity is strongly associated with Behcet's disease (BD) (for references see Baricordi et al., 1986), a multisystem vasculitis of unknown aetiology, for which an immunological pathogenesis has been proposed (O'Duffy et al., 1983; O'Duffy et al., 1990). Neutrophil abnormalities observed in BD patients even during clinical remission suggest prominent involvement of these phagocytic cells in the pathogenesis of the disease (Niwa et al., 1982). In order to clarify how HLA B51 antigen might confer susceptibility to BD, we have investigated neutrophil function in 13 B51-positive and 13 B51-negative healthy subjects. Lymphocyte spontaneous proliferation and circulating immune complexes were also evaluated. Whereas neutrophils from B51-positive subjects showed an increase in the chemotactic response toward casein (P = 0.003) and LPS (P = 0.033) and also in the PMA-induced superoxide production (P = 0.008) no evidence of enhanced lymphocyte activation emerged. These results suggest that the HLA region can exert a regulatory control on PMN functions.

Chromosome aberration in lymphocytes from Behçet's disease

Peripheral lymphocytes from 14 patients with Behçet's disease (BD) were examined for frequencies of chromosomal aberration. The frequency of gaps and breaks were not high in patients with BD but the frequency of dicentrics was increased in patients treated with colchicine or anticancer medicines. Patients treated with neither colchicine nor anticancer medicines showed no increased frequency of dicentrics. Our data suggested that the effect of treatment with colchicine or anticancer medication was one of the causes of the chromosome aberration observed in some BD lymphocytes. No numerical abnormality was observed in BD lymphocytes.

Association between the 65-kilodalton heat shock protein, Streptococcus sanguis, and the corresponding antibodies in Behçet's syndrome

The etiology of Behcet's syndrome (BS) is unknown, but a number of streptococcal species have been implicated. A hypothesis was postulated that a shared antigen, such as a stress protein, might account for some of these findings. Indeed, a rabbit antiserum against a 65-kDa heat shock protein of Mycobacterium tuberculosis revealed a corresponding 65-kDa band with all six Streptococcus sanguis strains examined and S. pyogenes but not with S. salivarius. By applying a panel of nine monoclonal antibodies to the mycobacterial 65-kDa heat shock protein, an approximately 65-kDa antigen was identified in the uncommon serotypes of S. sanguis ST3 and H.83 and one with a different Mr was identified in KTH-1 and S. pyogenes. Monoclonal antibodies Y1.2, C1.1, II H9, and ML30, which reacted with these streptococci, recognize residues 11 to 27, 88 to 123, 107 to 122, and 276 to 297 of the 65-kDa heat shock protein, respectively, suggesting that these residues are conserved among some uncommon serotypes of S. sanguis and S. pyogenes. Immunoblot analyses of sera from patients with BS for immunoglobulin A (IgA) and IgG antibodies revealed bands of 65 to 70 kDa with the mycobacterial heat shock protein, S. sanguis strains, and S. pyogenes, although these reactivities were also found to a lesser extent in controls. A 65- to 70-kDa band was found more frequently with S. sanguis KTH-2 or KTH-3 and IgA in serum from patients with BS than with serum from controls (P less than 0.02). Antibodies in serum were then studied by a radioimmunoassay, and in patients with BS this revealed significantly raised IgA antibodies to the recombinant 65-kDa mycobacterial heat shock protein and to soluble protein extracts of S. sanguis ST3, KTH-1, KTH-2, and KTH-3. Whereas significant anti-65-kDa heat shock protein and anti-S. sanguis ST3 antibodies were also found in sera from patients with rheumatoid arthritis and recurrent oral ulcers, the anti-S. sanguis KTH-1, KTH-2, and KTH-3 antibodies were confined to BS. The results are consistent with the hypothesis that some of the streptococcal antigens are associated with heat shock or stress proteins, which will need to be formally established by isolating heat shock proteins from streptococci.

Behçet's disease

Recent studies have revealed the important role of streptococci in the etiology of Behçet's disease. Among patients with Behçet's disease, there is a high incidence of a history of streptococcal infections. Certain antigens of streptococci induced not only cutaneous, delayed-type hypersensitivity, but also systemic attacks of Behçet's disease when skin tests were performed. Neutrophil-activating lymphokines are produced when streptococcal antigen reacted with lymphocytes from patients with Behçet's disease. The first international diagnostic criteria for Behçet's disease were prepared by multicenter studies and published recently. With recent progress in diagnostic imaging techniques, magnetic resonance imaging and position emission tomography are particularly important for the diagnosis of neuro-Behçet's disease. In Japan, cyclosporin was also proved to be effective for eye lesions of Behçet's disease in a double-blind clinical trial comparing this drug with colchicine.

[Clinical aspects of Behcet's syndrome]

Behçet's syndrome is characterized by the recurrent ulceration of the genitals, aphthous lesions of the mouth, uveitis, or iridocyclitis followed by hypopyon. Morbidity is increasing in the regions of the Central and North Europe. The disease is endemic in the region of Mediterranean Sea and Japan. Clinical course of Behçet's syndrome in WHO classification in 4 patients in discussed. Aphthous stomatitis, ulceration of the genitals and iridocyclitis dominated in the symptomatology. Several laboratory tests including complement, immunoglobulins and HLA B-27 were carried out. No abnormal values were seen. A survey of literature on the epidemiology, pathophysiology, and therapy is given.