Akihide Ohta

Very early development of steroid-associated osteonecrosis of femoral head in systemic lupus erythematosus: prospective study by MRI

The objective of this study was to define prospectively the early development of corticosteroid-induced osteonecrosis of femoral head (ONF) in patients with systemic lupus erythematosus (SLE) and to identify the association of initial steroid treatment with the development of early (silent) ONF. Forty-five patients who were newly diagnosed as having SLE and required 40 mg/day or more prednisolone were enrolled. To detect silent ONF, examinations using magnetic resonance imaging (MRI) were done three months after starting steroid therapy, followed by every year’s MRI and plain radiography for over five years. Clinical and laboratory data were compared between silent ONF and non-ONF groups. Of 45 patients, 15 (33%) developed silent ONF and five (11%) symptomatic ONF. It was of interest that MRI detected silent ONF very early (by three months) in 14 patients (93%). It should be noted that pulse therapy with 1000 mg/day methylprednisolone was found to be done very frequently (13 of 15, 87%) in the silent ONF group compared to non-ONF group (11 of 30, 37%) (P, 0.01) although other clinical features were not significantly different between both groups. High dose corticosteroids caused elevation of serum levels of total cholesterol, albumin, and leukocyte count in most of patients. The degree of elevation of those parameters at one or three months was more prominent in the silent ONF group. In particular, the change ratio of total cholesterol at one month was outstanding in the silent ONF group compared to non-ONF group (0.551 versus 0.374, P, 0.05). In conclusion, pathological ONF develops very early in one-third of SLE patients who received high dose corticosteroids and steroid pulse therapy could be a significant risk factor. An abrupt elevation of serum total cholesterol and/or sensitivity to steroids seem to be associated with the pathogenesis of ONF.

Retinal disease in patients with systemic lupus erythematosus

OBJECTIVE To investigate the incidence of retinopathy in systemic lupus erythematosus (SLE) and to clarify its significance in relation to other clinical manifestations. METHODS A cross sectional study on lupus retinopathy was made in 69 patients with SLE. One expert ophthalmologist examined the ocular fundi of the lupus patients without any information of their disease state. Clinical and laboratory findings in the patients with retinopathy and those without were compared. RESULTS Retinopathy was found in 7/69 (10%) patients. The findings included haemorrhages, vasculitis, cotton wool spots, and hard exudates, all of which were considered to reflect vascular damage. Retinopathy was found to be associated with the presence of anticardiolipin antibody (p<0.05) and with central nervous system lupus (p<0.01). The patients with retinopathy had higher levels of serum creatinine than the patients without retinopathy (p<0.01). The disease activity of lupus, as assessed by the maximum SLE disease activity index (SLEDAI) score of the patients, was also significantly higher in the patients with retinopathy (p<0.03). CONCLUSION Incidence of retinopathy in SLE was similar to that in previous reports and it may reflect tissue microangiopathy, particularly associated with vasculitis or anticardiolipin antibodies, or both.

B cells lacking RP105, a novel B cell antigen, in systemic lupus erythematosus

OBJECTIVE RP105 is a leucine-rich repeat (LRR) protein found on all mature mouse B cells. Its function is poorly defined, although it has been suggested that RP105 activates B cells to make them resistant to apoptosis. The human homolog of RP105 has been reported, but knowledge of its function is limited. We explored the expression and the function of the human homolog of murine RP105 on B cells in patients with systemic lupus erythematosus (SLE). METHODS The expression of RP105 and various markers on B cells in patients with SLE was analyzed using monoclonal antibodies and flow cytometry. Susceptibility to corticosteroid-induced apoptosis was examined by annexin V binding, and the production of immunoglobulin by RP105-negative B cells was examined by intracellular staining of IgG. RESULTS As in mice, virtually all B cells in the peripheral blood of normal humans expressed the RP105 molecule. However, a significant proportion of circulating B cells (15.9%) in SLE patients were RP105 negative. Serial analyses of B cells in 7 SLE patients revealed that RP105-negative B cells markedly decreased in parallel with a reduction in disease activity (from 35.2% to 3.3%; P = 0.000003). The SLE Disease Activity Index and serum levels of IgG also correlated with the percentage of RP105-negative B cells. The phenotype of RP105-negative B cells was defined as CD95-positive, CD86-positive, CD38-bright, IgD-negative, IgM-dull, indicating that the cells were highly activated, as further suggested by the detection of intracellular IgG. RP105-negative B cells were clearly distinct from CD5-positive B1 cells. In vitro experiments indicated that RP105-negative B cells were susceptible to corticosteroid-induced apoptosis. CONCLUSION These findings suggest that loss of RP105 is associated with B cell activation and increased disease activity in SLE patients.

Interferon regulatory factor 5 is critical for the development of lupus in MRL/lpr mice

OBJECTIVE Interferon regulatory factor 5 (IRF-5) is a transcription factor that mediates intracellular signals activated by engagement of Toll-like receptors (TLRs). IRF5 polymorphisms are associated with an increased or decreased risk of systemic lupus erythematosus (SLE) in various human populations, but the precise role of IRF5 in SLE development is not fully understood. This study was undertaken to examine the role of IRF5 in the development of murine lupus. METHODS We crossed gene-targeted IRF5-deficient (IRF5(-/-) ) mice with MRL/MpJ-lpr/lpr (MRL/lpr) mice and examined the progeny for survival, glomerulonephritis, autoantibody levels, immune system cell populations, and dendritic cell function. RESULTS IRF5(-/-) MRL/lpr mice survived longer than control IRF5(+/+) MRL/lpr mice and displayed only very mild glomerulonephritis. Autoantibodies to SLE-related nuclear antigens were lower in IRF5(-/-) MRL/lpr mouse serum, and numbers of activated CD4+ T cells were reduced in the spleen. Splenic DCs from IRF5(-/-) MRL/lpr mice produced lower levels of inflammatory cytokines when treated in vitro with TLR-7 or TLR-9 ligands or immune complexes. Interferon-α production in response to CpG was also decreased. CONCLUSION Our results show that IRF5 is a crucial driver of lupus development in mice, and indicate that IRF5 may be an attractive new target for therapeutic intervention to control disease in SLE patients.

Prevention of steroid-induced osteonecrosis of femoral head in systemic lupus erythematosus by anti-coagulant.

Although osteonecrosis of femoral head (ONF) is one of the serious complications in systemic lupus erythematosus (SLE) associated with corticosteroid therapy, there has been few trials of prevention of ONF described. We aimed to prevent ONF in steroid-treated SLE patients using anticoagulant, warfarin, conducting a multicenter prospective study. Sixty newly diagnosed SLE patients requiring 40 mg/day or more prednisolone were alternately assigned to either of two groups; a warfarin group and a control one. Warfarin (1 ∼ 5 mg/day) was started together with the beginning of steroid therapy and continued at least for three months. Patients were observed for the development of silent ONF by magnetic resonance imaging (MRI) and symptomatic ONF by plain radiography for over five years. The warfarin group consisted of 31 patients (62 hips) and the control one 29 patients (58 hips). Silent ONF developed in 13 hips (21%) and 19 hips (33%) in the warfarin group and the control group, respectively (P = 0.13). On the other hand, warfarin tended to prevent symptomatic ONF; only three hips of 62 (4.8%) in the warfarin group and eight hips of 58 (14%) in the control group (P = 0.08) developed silent ONF. It was also found that silent ONF developed, if it did, very early; within three months in 16 of 18 patients (89%). Among risk factors for silent ONF, steroid pulse therapy was most outstanding and it seemed to overcome the effect of warfarin. Taken together, for the time being, anticoagulant therapy, if not significantly sufficient, may be of use for the prevention of steroid-induced ONF in SLE. We consider that this study added to important evidence for the pathogenesis and prevention of ONF.

Therapeutic response of patients with adult Still’s disease to biologic agents: multicenter results in Japan

ObjectiveThe efficacy of biologics in treating adult Still’s disease (ASD) is suggested, but the information is still lacking and the validation is insufficient. To determine the efficacy of several biologic agents in refractory ASD in Japan, a multicenter survey was performed.MethodClinical data on 16 ASD patients who had been treated with at least 1 of the biological agents (total 24 occasions) were collected retrospectively.ResultsInfliximab was used in 9 cases, etanercept in 4, and tocilizumab in 11. Half of the patients that had been treated initially with infliximab or etanercept were changed to another biologics. Tocilizumab was effective in cases switched from another 2 drugs. Tocilizumab showed efficacy in treating both systemic and arthritic symptoms and showed apparent steroid-sparing effect and the highest continuation rate.ConclusionTocilizumab may be a promising biologic agent in refractory ASD.

Difference in B cell activation between dermatomyositis and polymyositis: analysis of the expression of RP105 on peripheral blood B cells

BACKGROUND It has previously been shown that RP105, a new B cell surface protein, is lost in activated human B cells. OBJECTIVE To investigate whether there is a difference in B cell activation between patients with dermatomyositis (DM) and those with polymyositis (PM) using RP105 as a marker. METHODS The population of RP105 negative B cells (activated B cells) in the peripheral blood mononuclear cells of seven patients with dermatomyositis (DM) and 11 with polymyositis (PM) was analysed by flow cytometry. RESULTS The percentage of RP105 negative B cells in the peripheral blood of patients with PM was low (5.8 (SD 2.4)%), similar to that of normal subjects. In contrast, all patients with DM showed increased RP105 negative B cell populations (33.0 (6.9)%). Bronchoalveolar lavage fluid from a patient with DM and active interstitial pneumonitis contained a large number of RP105 negative B cells. CONCLUSION These findings suggest that the expansion of RP105 negative B cells is a hallmark of DM, and that B cell activation in DM may be pathogenetically different from that in PM.

Toll-like receptor homolog RP105 modulates the antigen-presenting cell function and regulates the development of collagen-induced arthritis.

IntroductionRP105 is a Toll-like receptor homolog expressed on B cells, dendritic cells (DCs), and macrophages. We investigated the role of RP105 in the development of collagen-induced arthritis (CIA).MethodsCIA was induced in RP105-deficient DBA/1 mice and the incidence and arthritis index were analyzed. The cytokine production by spleen cells was determined. The functions of the DCs and regulatory T cells (Tregs) from RP105-deficient or control mice were determined by adding these cells to the lymph node cell culture. Arthritis was also induced by incomplete Freunds adjuvant (IFA) plus collagen or by injecting anti-collagen antibody and lipopolysaccharide.ResultsRP105-deficient mice showed accelerated onset of arthritis and increased severity. Interferon-gamma (IFN-γ) and tumor necrosis factor-alpha production by spleen cells from RP105-deficient mice was increased in comparison with that from wild-type mice. The DCs from RP105-deficient mice induced more IFN-γ production, whereas Tregs from those mice showed less inhibitory effect against IFN-γ production. RP105-deficient mice also showed more severe arthritis induced by collagen with IFA.ConclusionsThese results indicate that RP105 regulates the antigen-presenting cell function and Treg development, which induced the attenuation of the cell-mediated immune responses and, as a result, suppressed the development of CIA.

Retinal findings in systemic sclerosis: a comparison with nailfold capillaroscopic patterns

Objective: To determine the prevalence of retinal disease in systemic sclerosis (SSc) and to characterise the findings of retinopathy. Additionally, to analyse the association of retinal disease with other clinical/laboratory findings, particularly the findings of nailfold capillaries in patients with SSc. Methods: Photographs of the ocular fundi were taken and were evaluated by an ophthalmologist who was unaware of the SSc status of the patients. The nailfold capillaries were analysed with a dermatoscope. Patients were divided into two groups according to the presence (group A) or absence (group B) of retinal disease. Results: Retinal findings of the patients with SSc consisted of hard exudates, vascular tortuosity, microhaemorrhage, and macular degeneration. The prevalence of retinal disease among the patients with SSc was 34% (10/29), compared with 8%(3/38) among the controls (p=0.011). The mean systolic blood pressure and the age of the patients in group A were significantly higher than those in group B. However, there was no significant difference in the nailfold capillary damage between groups A and B. Conclusion: Retinal abnormalities are often seen in patients with SSc and they may reflect the vascular changes characteristic of SSc. However, retinal changes may differ in quality from the changes of nailfold capillaries.

Autoantibody-producing RP105− B cells, from patients with systemic lupus erythematosus, showed more preferential expression of BCMA compared with BAFF-R than normal subjects

OBJECTIVE B cells lacking RP105 produce autoantibodies in patients with SLE. Expression of B-cell activating factor (BAFF) binding receptors (BBRs) and survival of RP105(-) B cells from SLE patients were examined. METHODS Detection of difference of gene expression between RP105(-) and RP105(+) B cells was done by DNA microarrays. Surface expression was confirmed by flow cytometry. The contribution of BAFF, a proliferation-inducing ligand (APRIL) and monomers/trimers of sCD40L to survival of RP105(-) and RP105(+) B cells was examined. RESULTS Gene expression of B-cell maturation antigen (BCMA) was different among BBRs in RP105(-) and RP105(+) B cells in SLE. Preferential expression of BCMA on RP105(-) B cells was confirmed compared with RP105(+) B cells by flow cytometry, although BAFF receptor (BAFF-R) expression on RP105(-) B cells was significantly lower. Additionally, relative ratios of BCMA/BAFF-R expression on RP105(-) B cells were increased significantly in SLE patients compared with normal subjects. Stimulation by sCD40L decreased the number of surviving RP105(-) and RP105(+) B cells in vitro. RP105(+) B cells were not rescued from sCD40L-induced cell death by BAFF and/or APRIL. In contrast, either BAFF or APRIL maintained the survival of RP105(-) B cells due to avoidance of cell death. Activated RP105(-) B cells reduced BAFF-R and increased BCMA levels. CONCLUSIONS RP105(-) B cells from SLE patients showed more preferential expression of BCMA compared with BAFF-R than normal subjects, and were possibly regulated by BAFF/APRIL. Our results provide a new insight of BCMA and their ligands in B cells from SLE patients.