Circulating immune complexes in active Behçet's disease.

Levels of immune complexes (IC) were determined by the Raji-cell and C1q-binding radioimmunoassays in the sera of eighteen patients with Behçet's disease. Eight patients (44%) were found to have significantly elevated levels of IC (range 56 to 1600 microgram equivalent aliquots of heat aggregated IgG (AHG/ml) by the former test and nine by the latter (7 to 500 microgram equivalent AHG/ml). The presence of IC showed a significant correlation with disease activity score (P = 0.003, Mann-Whitney Rank Sum Test). Abnormal values of IC tended to remain abnormal when sera were retested after 1 year. There was no correlation between IC and duration of disease or any specific organ involvement. The IC were found predominantly in fractions of about 19S and greater when fractionated by sucrose density gradient or Sephadex column techniques. The results suggest the possibility that IC may contribute to the pathophysiology of Behçet's disease.     

Behçet's syndrome: a case study

This is the case report of a woman who for many years was a diagnostic puzzle. Her various problems were eventually identified as features of Behçet's syndrome, which is uncommon in this country. Besides the known clinical symptoms of the disease, this patient has suffered intermittently from dysmenorrhoea and menorrhagia, which may well be features of this disorder which have not previously been documented. There is no sign of remission for this patient, but awareness of her condition should lead to more sympathetic management of these cases.     

Polymorphonuclear leucocyte function in Behçet's disease.

Polymorphonuclear leucocyte function was investigated in 19 patients with active Behçet's disease. Spontaneous free leucocyte migration was found to be significantly reduced, yet after stimulation the leucocyte's chemotactic activity was considerably increase (p less than 0-05) when compared to control leucocytes. Control leucocytes migrated more rapidly when incubated in serum taken from patients with Behçet's disease (p less than 0-005). The enhanced chemotactic activity in Bechçet's disease appears to be due to both serum and intrinsic leucocyte factors. Spontaneous nitroblue tetrazolium reduction was found to be normal, although after stimulation leucocyte nitroblue tetrazolium reduction was lower than in the control group (P less than 0-025), as was leucocyte oxygen utilisation. It is suggested that the hyperreactive cellular inflammatory response that characterises Behçet's disease may be due to increased chemotactic activity and minor alterations in functional metabolic activity of leucocytes.     

Lymphocyte abnormalities in Behçet''s syndrome.

In order to test indirectly the hypothesis that Behçet''s syndrome is caused by a virus, lymphocytes from eighty-six patients were evaluated for two parameters consistent with persistent virus infection: chromosomal abnormalities and decreased ability to herpes simplex virus type I (HSV) to grow in lymphocyte cultures stimulated by PHA. Whereas HSV grew in lymphocytes cultured from all normal donors, replication was impaired in lymphocytes from 37% of the patients with Behçet''s syndrome. This figure is increased to 57% if patients receiving steroids or cytotoxic drugs were excluded. Lymphocytes were scored as chromosomally abnormal from sixteen of the thirty-eight patients examined, compared with only one of seventeen normal controls. There was damage to specific chromosomes in four patients. The frequency with which chromosomal abnormalities were detected was significantly related to failure to replicate HSV and inversely related to concomitant steroid treatment. The findings are consistent with a viral aetiology for Behçet''s syndrome but other explanations are not excluded.     

Interferon-gamma production by peripheral blood mononuclear cells from patients with Behçet's syndrome.

Interferon-gamma (IFN-gamma) production by peripheral blood mononuclear cells (MNC) from patients with Behçet's syndrome was compared with production by MNC from control donors. There was no evidence of significant spontaneous production of either IFN-gamma or interferon-alpha (IFN-alpha) by unstimulated MNC from patients or controls but phytohaemagglutinin treatment of MNC induced IFN-gamma in both patient and control groups. Significantly higher titres of IFN-gamma were produced by MNC from patients with Behçet's syndrome than MNC from patients with other inflammatory diseases (P = 0.005), hospital controls (P = 0.036) or healthy controls (P = 0.009). No IFN was detected in plasma from patients or controls.     

Antineutrophil Cytoplasmic Antibody Positivity Is Associated with Vascular Involvement in Behçet's Disease

PurposeWe investigated whether antineutrophil cytoplasmic antibody (ANCA) positivity is associated with vascular manifestations at diagnosis of Behçet''s disease (BD) and poor outcomes during follow-up.Materials and MethodsWe retrospectively reviewed the medical records of 1060 patients with BD. Among them, 808 patients could be diagnosed with BD based on the revised version of the International Criteria for Behçet''s Disease (ICBD) in 2014 (2014 ICBD criteria) and 588 patients could be diagnosed with BD based on the International Study Group (ISG) criteria proposed in 1990 (1990 ISG criteria). We examined the sites and patterns of vascular involvement in the BD patients at diagnosis and evaluated adverse outcomes during follow up, such as all-cause mortality, acute coronary syndrome, and deep vein thrombosis.ResultsAmong the 808 patients with BD based on the 2014 ICBD criteria, the rate of ANCA positivity at diagnosis was 2.2%. ANCA-positive BD patients exhibited a higher frequency of overall vascular manifestations (22.2% vs. 6.1%) and higher frequencies of vascular involvement in the upper extremities and visceral arteries than ANCA-negative BD patients (5.6% vs. 0.1% and 5.6% vs. 0.1%). Among the 588 BD patients based on the 1990 ISG criteria, similarly, ANCA-positive BD patients exhibited a higher frequency of vascular manifestations than ANCA-negative BD patients. ANCA positivity, however, did not seem to be associated with poor outcomes in BD patients during follow up.ConclusionANCA positivity in BD patients was found to be associated with cross-sectional vascular involvement in the upper extremities and visceral arteries at diagnosis but was not predictive of poor outcomes during follow-up.     

Natural killer cells in Behçet''s disease.

We studied natural killer (NK) cell activity and numbers in the peripheral blood obtained from patients with Behçet''s disease (BD) in inactive and convalescent stage, and from healthy controls. Ratios of helper/suppressor cells (OKT4/OKT8) were below 1.0 in patients with active stage and were normal in the convalescent stage of BD. A relative increase of OKT8+ cells and at the same time of Leu 7+ cells was obtained in the active and convalescent BD stages. Double marker analysis revealed that the sub-population of cells expressing both the T8+ and the Leu 7+ antigen (T8+/Leu 7+) was increased in patients with active stage, and normal in the convalescent stage. The frequency of cells reactive with Leu 11 monoclonal antibody (active NK cells) was evaluated in patients with BD. Data from peripheral blood showed an increased sub-population of T8+/Leu 7+ double marker cells, and a decreased Leu 11+ cell sub-population in patients with active BD, but the majority of Leu 7+ cells in patients with convalescent stage lacked OKT8 antigen when investigated in a double marker system. A parallel increase of Leu 11+ cells was observed in the convalescent stage. This phenotypic analysis was carried out with the NK in vitro functional evaluation of cell populations from peripheral blood. NK cell activity in the clinically active stage of BD was significantly lower than that of healthy controls and patients in the convalescent stage. The decrease of peripheral blood NK function in patients with active BD may be related to the presence of immature forms of NK cells and/or to the increased percentage of T8+/Leu 7+ cells.     

An immunogenetic basis for the tissue involvement in Behçet''s syndrome.

The multifocal involvement in Behçet''s syndrome was grouped into a spectrum of four types, three of which appeared to have an immunogenetic basis. HLA-B5 was related to the ocular type of Behçet''s syndrome (relative risk 7.3), HLA-B27 to the arthritic type (relative risk 12.1) and HLA-B12 to the muco-cutaneous type (relative risk 3.9). The concept that recurrent oral ulceration and Behçet''s syndrome may belong to a disease spectrum is substantiated by the natural course of the disease. Furthermore, patients with recurrent oral ulcers share with the muco-cutaneous type of Behçet''s syndrome a significantly increased frequency of HLA-B12 (relative risk 2.6). The HLA markers may also prove to be significant in the differential diagnosis and prognosis of a disease which may present under a confusing variety of clinical manifestations.     

Heat shock protein peptides reactive in patients with Behçet's disease are uveitogenic in Lewis rats.

Mycobacterial and homologous human heat shock protein T cell peptide epitopes specific for T lymphocytes in Behçet's disease were investigated for their pathogenicity in Lewis rats. The potential pathogenicity of eight peptides and two controls was assessed by administering the peptides in enriched Freund's adjuvant into the footpads of male Lewis rats. Anterior uveitis which is a major manifestation of Behçet's disease was induced with two out of the four mycobacterial and all four homologous human peptides. The most effective peptides inducing iridocyclitis in 64-75% of rats were peptides with amino acids 336-351 and 136-150, derived from the sequence of the human 60-kD heat shock protein. A few of the rats also showed evidence of focal loss of photoreceptors. These results suggest that selected peptides within heat shock protein 60 kD which function as T cell epitopes in Behçet's disease are capable of inducing uveitis in rats. This supports the view that the peptide T cell determinants may be involved in the pathogenesis of Behçet's disease.     

Lymphocyte responses in juvenile chronic arthritis and Behçet's disease--cell number requirements and effects of glucocorticosteroid therapy.

Peripheral blood mononuclear cells from patients with clinically active Behçet's disease or juvenile chronic arthritis (JCA) gave high responses to phytohaemagglutinin (PHA) in vitro prior to prednisolone therapy and low responses when taking prednisolone in comparison with cells from control individuals. Such effects were not significantly different at the six concentrations of cells or the four times in culture studied. Differences from controls were also seen with cells from clinically controlled, prednisolone treated Behçet's patients; the cells responded better than controls at low cell concentrations and early times in culture, the reverse occurring at higher concentrations and later times. This pattern of response suggests the presence of a higher than normal proportion of responsive cells in these patients. These studies suggest that not only is a still wider range of culture conditions required to assess fully the differences in lymphocyte function related to disease activity and prednisolone treatment in JCA or Behçet's, but also that the use of a narrow set of 'optimized' conditions may be misleading.     

Auto-oxidative damage in Behçet's disease--endothelial cell damage following the elevated oxygen radicals generated by stimulated neutrophils.

The functions of phagocytes are enhanced in patients with Behçet's disease, therefore, we investigated the neutrophil-derived oxygen intermediates (OI) and lysosomal enzymes from 17 patients receiving glucocorticosteroids (steroids) and colchicine. Cultured endothelial cells were incubated with neutrophils to assess tissue injury. In cases of the complete type, in the active stage of the disease, OI production was markedly increased. The other patients showed significantly higher OI and higher lysosomal enzyme levels than patients with other diseases (controls) receiving drug therapy. Cytotoxicity tests showed that the 51Cr release was also significantly higher. The destruction of desmosomes and cell deformation were demonstrated electron microscopically. The simultaneous addition of superoxide dismutase and catalase in the cell culture decreased the 51Cr release to control levels. These findings suggest that neutrophils from patients with Behçet's disease generate high levels of OI, resulting in endothelial tissue damage.     

Evaluation of T cell subsets in Behçet''s syndrome using anti-T cell monoclonal antibodies.

Several immunological abnormalities have been described in Behçet''s syndrome, the multisystem disease characterized by the triad of relapsing iridocyclitis with recurrent oral and genital ulcerations. In the present study we have evaluated T cell subsets in the peripheral blood of patients suffering from Behçet''s syndrome, using a panel of anti-T cell monoclonal antibodies. When compared with normal subjects, patients with Behçet''s syndrome show a discrepancy between the number of T3+ cells and those forming rosettes with sheep erythrocytes, a significantly higher number of T4+ and T8+ double labelled cells, as well as of T6+ lymphocytes in the peripheral blood. The percentage of T8 T lymphocytes is increased, thus lowering the T4+/T8+ cell ratio. The results of this study indicate that a complex imbalance of T cell subsets is present in Behçet''s syndrome and give a rationale for possible treatment of these patients with immunomodulators.     

The high prevalence of HLA-B5 in Behçet''s disease.

Sixteen of the nineteen (84%) patients with Behçet''s disease in Turkey had HLA-B5; the prevalence of HLA-B5 among 150 controls was 27%.     

Cytotoxic T cells against herpes simplex virus in Behçet''s disease.

Lymphocytes from 36 patients with Behçet''s disease (20 in remission and 16 in active phase) were stimulated in vitro with herpes simplex virus and then tested for their ability to generate cytotoxic T cell responses to the virus. Significant cytotoxic responses were found. CD4+ and CD8+ subpopulations from the patients in remission generated specific cytotoxic activity against autologous target cells. These observations suggested that CD4+ and CD8+ cytotoxic T cells may have an important host response in herpes virus infection in Behçet''s disease.     

Role of γδ T lymphocytes in the development of Behçet's disease

Phenotypic and functional properties of γδ T cells, which play an important role in mucocutaneous immunity, were examined to elucidate whether immunological abnormality in Behc¸et's disease may be related to a specific T cell population. We found that CD45RA⁺Vγ9⁺Vδ2⁺γδ T cells, which constitute a minor population of γδ T cells in healthy individuals, were increased in number in Behc¸et's disease irrespective of disease activity. This CD45RA⁺ subset of γδ T cells in the active, but not inactive, phase of this disease expressed IL-2Rβ and HLA-DR, suggesting that they are activated in vivo in active Behc¸et's disease. In addition, the CD45RA⁺γδ T cells produced extreme amounts of tumour necrosis factor and contained perforin granules. These data indicate that a phenotypically distinct subset of γδ T cells, CD45RA⁺CD45RO⁻Vγ9⁺Vδ2⁺, may contribute to immunological abnormalities which may lead to complexity of pathophysiology in Behc¸et's disease.     

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.     

Natural killer cell activity, interferon-gamma and antibodies to herpes viruses in patients with Behçet''s disease.

Interferon-gamma (IFN-gamma) titres in 20 patients with active Behçet''s disease were examined and compared with those of 20 normal donors. Sera from Behçet''s disease patients revealed an IFN-gamma increase but no correlation between IFN level and natural killer (NK) activity. The analysis of lymphocyte subsets by monoclonal antibodies registered an increase of CD8+ T subpopulation and cells co-expressing CD8(+)-Leu7a+ markers. Moreover, a high number of cells expressing CD25+ and HLA-DR+ phenotype has been noted in patients with active Behçet''s disease. Serological analysis showed a high level of IgG antibodies to HSV-1. The increase of IFN-gamma titre, the high number of activated T cells and the increasing level of IgG antibodies to HSV-1 are important manifestations during the active stage of Behçet''s disease. These findings are discussed in relation to the immunopathogenesis of Behçet''s disease.