Syuichi Koarada

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.

Genetic Control of Autoimmunity: Protection from Diabetes, but Spontaneous Autoimmune Biliary Disease in a Nonobese Diabetic Congenic Strain

At least 20 insulin-dependent diabetes (Idd) loci modify the progression of autoimmune diabetes in the NOD mouse, an animal model of human type 1 diabetes. The NOD.c3c4 congenic mouse, which has multiple B6- and B10-derived Idd-resistant alleles on chromosomes 3 and 4, respectively, is completely protected from autoimmune diabetes. We demonstrate in this study, however, that NOD.c3c4 mice develop a novel spontaneous and fatal autoimmune polycystic biliary tract disease, with lymphocytic peribiliary infiltrates and autoantibodies. Strains having a subset of the Idd-resistant alleles present in the NOD.c3c4 strain show component phenotypes of the liver disease: NOD mice with B6 resistance alleles only on chromosome 3 have lymphocytic liver infiltration without autoantibody formation, while NOD mice with B10 resistance alleles only on chromosome 4 show autoantibody formation without liver infiltration. The liver disease is transferable to naive NOD.c3c4 recipients using splenocytes from affected NOD.c3c4 mice, demonstrating an autoimmune etiology. Thus, substitution of non-NOD genetic intervals into the NOD strain can prevent diabetes, but in turn cause an entirely different autoimmune syndrome, a finding consistent with a generalized failure of self-tolerance in the NOD genetic background. The complex clinical phenotypes in human autoimmune conditions may be similarly resolved into largely overlapping biochemical pathways that are then modified, potentially by alleles at a few key chromosomal regions, to produce specific autoimmune syndromes.

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.

Increased Nonobese Diabetic Th1:Th2 (IFN-γ:IL-4) Ratio Is CD4+ T Cell Intrinsic and Independent of APC Genetic Background

Autoreactive CD4+ T cells play a major role in the pathogenesis of autoimmune diabetes in nonobese diabetic (NOD) mice. We recently showed that the non-MHC genetic background controlled enhanced entry into the IFN-γ pathway by NOD vs B6.G7 T cells. In this study, we demonstrate that increased IFN-γ, decreased IL-4, and decreased IL-10 production in NOD T cells is CD4 T cell intrinsic. NOD CD4+ T cells purified and stimulated with anti-CD3/anti-CD28 Abs generated greater IFN-γ, less IL-4, and less IL-10 than B6.G7 CD4+ T cells. The same results were obtained in purified NOD.H2b vs B6 CD4+ T cells, demonstrating that the non-MHC NOD genetic background controlled the cytokine phenotype. Moreover, the increased IFN-γ:IL-4 cytokine ratio was independent of the genetic background of APCs, since NOD CD4+ T cells generated increased IFN-γ and decreased IL-4 compared with B6.G7 CD4+ T cells, regardless of whether they were stimulated with NOD or B6.G7 APCs. Cell cycle analysis showed that the cytokine differences were not due to cycle/proliferative differences between NOD and B6.G7, since stimulated CD4+ T cells from both strains showed quantitatively identical entry into subsequent cell divisions (shown by CFSE staining), although NOD cells showed greater numbers of IFN-γ-positive cells with each subsequent cell division. Moreover, 7-aminoactinomycin D and 5-bromo-2′-deoxyuridine analysis showed indistinguishable entry into G0/G1, S, and G2/M phases of the cell cycle for both NOD and B6.G7 CD4+ cells, with both strains generating IFN-γ predominantly in the S phase. Therefore, the NOD cytokine effector phenotype is CD4+ T cell intrinsic, genetically controlled, and independent of cell cycle machinery.

Increased Entry into the IFN-γ Effector Pathway by CD4+ T Cells Selected by I-Ag7 on a Nonobese Diabetic Versus C57BL/6 Genetic Background

IFN-γ-mediated Th1 effects play a major role in the pathogenesis of autoimmune diabetes in nonobese diabetic (NOD) mice. We analyzed functional responses of CD4+ T cells from NOD and B6.G7 MHC congenic mice, which share the H2g7 MHC region but differ in their non-MHC genetic background. T cells from each strain proliferated equally to panstimulation with T cell lectins as well as to stimulation with glutamic acid decarboxylase 524–543 (self) and hen egg lysozyme 11–23 (foreign) I-Ag7-binding peptide epitopes. Despite comparable proliferative responses, NOD CD4+ T cells had significantly increased IFN-γ intracellular/extracellular protein and mRNA responses compared with B6.G7 T cells as measured by intracellular cytokine analysis, time resolved fluorometry, and RNase protection assays. The increased IFN-γ production was not due to an increase in the amount of IFN-γ produced per cell but to an increase in the number of NOD CD4+ T cells entering the IFN-γ-producing pathway. The increased IFN-γ response in NOD mice was not due to increased numbers of activated precursors as measured by activation/memory markers. B6.G7 lymphoid cells demonstrated an absolute decrease in IFN-γ mRNA, an increase in IL-4 mRNA production, and a significantly decreased IFN-γ:IL-4 mRNA transcript ratio compared with NOD cells. CD4+ T cells from C57BL6 mice also showed significantly decreased IFN-γ production compared with CD4+ T cells from NOD.H2b MHC-congenic mice (which have an H2b MHC region introgressed onto an NOD non-MHC background). Therefore, the NOD non-MHC background predisposes to a quantitatively increased IFN-γ response, independent of MHC class II-mediated T cell repertoire selection, even when compared with a prototypical Th1 strain.

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.