Yoshiaki Tokano

Levels of IL-12 in the sera of patients with systemic lupus erythematosus (SLE)— relation to Th1- and Th2-derived cytokines

IL‐12 is a cytokine that induces Th1‐derived cytokines (interferon‐gamma (IFN‐γ) and IL‐2). The significance of IL‐12 in human autoimmunity is no clear, and the serum levels of IL‐12 in SLE are not clearly established. Therefore, we examined the levels of IL‐12 in 39 patients with active SLE, with sandwich ELISA. The levels of IL‐12 in patients were significantly higher than in normal subjects. Patients with high levels of IL‐12 also had high levels of IFN‐γ, while their levels of IL‐13 were significantly lower than in patients with normal levels of IL‐12. Patients with pulmonary involvement had high levels of IL‐12, and steroid therapy decreased the IL‐12 level in three patients. In a retrospective study of seven patients, various changes of IL‐12 and IL‐13 were recognized before disease flare. Thus, in SLE patients, the level of IL‐12 was increased and this increase was related to the change of Th1‐ or Th2‐derived cytokines with some organ involvement.

CD134L Engagement Enhances Human B Cell Ig Production: CD154/CD40, CD70/CD27, and CD134/CD134L Interactions Coordinately Regulate T Cell-Dependent B Cell Responses

CD134 is a member of the TNFR family expressed on activated T cells, whose ligand, CD134L, is found preferentially on activated B cells. We have previously reported that the CD70/CD27 interaction may be more important in the induction of plasma cell differentiation after the expansion phase induced by the CD154/CD40 interaction has occurred. When CD134-transfected cells were added to PBMCs stimulated with pokeweed mitogen, IgG production was enhanced in a dose-dependent fashion. Addition of CD134-transfected cells to B cells stimulated with Staphylococcus aureus Cowan I strain/IL-2 resulted in little if any enhancement of B cell IgG production and proliferation. We found that while CD134-transfected cells induced no IgG production by themselves, it greatly enhanced IgG production in the presence of CD40 stimulation or T cell cytokines such as IL-4 and IL-10. The addition of CD134-transfected cells showed only a slight increase in the number of plasma cells compared with that in the culture without them, indicating that an increased Ig production rate per cell is responsible for the observed enhancing effect of CD134L engagement rather than increase in plasma cell generation. These results strongly suggest different and sequential roles of the TNF/TNFR family molecules in human T cell-dependent B cell responses through cell-cell contacts and the cytokine network.

HLA antigens in Japanese patients with systemic lupus erythematosus

To determine the association of HLA antigens with SLE and the clinical findings of the disease, HLA antigens were tested in 58 Japanese patients with SLE, who fulfilled the ARA diagnostic criteria, along with 97 normal controls. HLA class I and II antigens were typed serologically using the antisera provided by the 11th HLA Workshop. Among the HLA class II antigens, further DRB, DQ and DP alleles were defined by DNA typing using the PCR/SSOP method. There were significantly more SLE patients with HLA-B39, DRB1*1501, DRB5*0101 and DQB1*0602 than normal controls. This result suggested that the haplotype of HLA-DRB1*1501-DRB5*0101-DQA1*0102-DQB1*0602 consists of the SLE-associated MHC markers in Japan. There were some positive and negative associations between the HLA antigens and clinical or serological findings in SLE. There is a possibility that some HLA alleles might be related to the clinical and/or serological subsets of SLE.

Soluble Fas molecule in the serum of patients with systemic lupus erythematosus

The serum level of soluble Fas (sFas) molecules in 35 patients with SLE was determined by enzyme-linked immunosorbent assay (ELISA) and its relation to other lymphocyte activation markers and clinical parameters was examined. The level of sFas increased significantly compared to that in normal subjects, consistent with previous reports. There was a significant correlation between the level of sFas and that of sCD4, suggesting some relation between sFas and activation of CD4+ T cells. Patients with lymphopenia tended to have low levels of sFas, making it possible to hypothesize that sFas protects against apoptosis. Although the change in the level of sFas with steroid therapy was variable, some relation to the differential activation of T cell subsets was suggested.

HLA-DP+ T cells and deficient interleukin-2 production in patients with systemic lupus erythematosus

In patients with systemic lupus erythematosus (SLE), frequency of the T cells positive for HLA-DP, one of the major histocompatibility complex (MHC) class II molecules, was markedly increased in peripheral blood lymphocytes (PBL), in association with an increase in the amount of specific cytoplasmic transcript of the HLA-DP gene segment. Cell cycle analysis showed that HLA-DP is an early activation marker of T cells and that the high ratios of HLA-DP+ T cells from SLE patients are associated with high frequency of T cells at early activation phases, mainly of G1A. Initial high ratios of HLA-DP+ T cells decreased to a great extent during 4 days of in vitro culture, in the absence of mitogens. This event was associated with decreases in the amount of HLA-DP transcript and the disappearance of activated T cells. Studies on the interleukin 2 (IL-2) production of T cells from patients with SLE demonstrated that while the PBL rich in HLA-DP+ T cells show a markedly low production of IL-2, preculture of these PBL restores the ability to produce IL-2. Thus, it appears that the T cells in patients with SLE are essentially intact with regard to the capacity to produce IL-2 and that T cell activation events continuously occurring in SLE patients are related to a deficiency in IL-2 production. The possible underlying mechanisms are discussed.

The Increased Interleukin-13 in Patients with Systemic Lupus Erythematosus: Relations to Other Thl-, Th2-Related Cytokines and Clinical Findings

The levels of interleukin-13 (IL-13) in patients with systemic lupus erythematosus (SLE) were examined and related to other Thl-/Th2- related cytokines, clinical manifestations and other markers. Serum levels of IL-13 and other cytokines, soluble markers were measured by enzyme-linked immunosorbent assay (ELISA). Patients with active SLE had a significantly increased level of EL-13. Most patients with high levels of IL-13 had higher levels of IL-6, and some patients had high levels of ylFN. These patients were divided into two groups according to the patterns of these increased cytokines; one with a high level of only Th2 related cytokines (IL-13 or IL-6) and another with high levels of both Th2 related and Thl related cytokines (γIFN or IL-2). The latter patients had high levels of soluble CD8 and CD23, and some of them had hemolytic anemia or pulmonary involvement, while most of the former patients had nephropathy. Thus, in SLE, the levels of IL-13 were increased, and the heterogeneity of increased Th2- and Thl-related cytokines was related to that of activation markers and clinical manifestations

Increased Foxp3+ CD4+ Regulatory T Cells with Intact Suppressive Activity but Altered Cellular Localization in Murine Lupus

Foxp3(+) CD4(+) regulatory T (T(reg)) cells play a pivotal role in the maintenance of dominant self tolerance. Understanding how the failures of immune control by T(reg) cells are involved in autoimmune diseases is important for the development of effective immunotherapies. In the present study, we analyzed the characteristics of endogenous T(reg) cells in (NZB x NZW) F1 (BWF1) mice, a murine model of systemic lupus erythematosus. Unexpectedly, T(reg) number and frequency in aged BWF1 mice with developing lupus nephritis were increased, not decreased, and in vitro suppressive activity in lymphoid organs was intact. In addition, T(reg) cells trafficked to target organs because cells were present in the kidney and lung. T(reg) cells of aged BWF1 mice exhibited altered localization within lymph organs, however, and an altered phenotype, with higher expression levels of chemokine receptors and activation markers, suggesting a highly activated cellular state. Notably, the expression levels of co-stimulatory molecules were also markedly enhanced in the T(reg) cells of aged BWF1 mice. Furthermore, T(reg) cells of BWF1 mice did not show any suppressive effects on antibody production in vitro. Taken together, we conclude that T(reg) cells in BWF1 mice are not predisposed to functional incompetence but rather are present in a highly activated state.

Hypocomplementemic urticarial vasculitis with Jaccoud’s arthropathy and valvular heart disease: case report and review of the literature

We describe a female Japanese patient with concomitant hypocomplementemic urticarial vasculitis, Jaccoud’s arthropathy and valvular heart disease. In 1996, she developed arthritis with swelling of both proximal interphalangeal joints and urticarial vasculitis on both arms that was resolved by administration of glucocorticoid (prednisolone 30 mg/day). Tests for antineutrophil cytoplasmic antibodies, antinuclear antibody and rheumatoid factor gave negative results. The findings of a skin biopsy examination were consistent with ‘leukocytoclastic vasculitis’. During 10 years of observation, the patient manifested polyarthritis leading to progressive deformity of the joints of the hands and feet (without loss of cartilage or erosion of bone), persistent urticaria exacerbated by cold and accompanied by hypocomplementemia and progressive cardiac valvular disease with mitral valve regurgitation. There are only three reports described previously documenting five patients with this rare combination of manifestations.

FTY720 exerts a survival advantage through the prevention of end-stage glomerular inflammation in lupus-prone BXSB mice

FTY720 is a novel investigational agent targeting the sphingosine 1-phosphate (S1P) receptors with an ability to cause immunosuppression by inducing lymphocyte sequestration in lymphoid organs. Systemic lupus erythematosus (SLE) is refractory autoimmune disease characterized by the production of a wide variety of autoantibodies and immune complex (IC)-mediated lupus nephritis. Among several SLE-prone strains of mice, BXSB is unique in terms of the disease-associated monocytosis in periphery and the reduced frequency of marginal zone B (MZ B) cells in spleen. In the present study, we examined the effect of FTY720 on lupus nephritis of BXSB mice. FTY720 treatment resulted in a marked decrease in lymphocytes, but not monocytes, in peripheral blood, and caused relocalization of marginal zone B (MZ B) cells into the follicle in the spleen. These changes did not affect the production of autoantibodies, thus IgG and C3 were deposited in glomeruli in FTY720-treated mice. Despite these IC depositions, FTY720-treated mice showed survival advantage with the improved proteinuria. Histological analysis revealed that FTY720 suppressed mesangial cell proliferation and inflammatory cell infiltration. These results suggest that FTY720 ameliorates lupus nephritis by inhibiting the end-stage inflammatory process following IC deposition in glomeruli.

Very low-dose cyclosporin treatment of steroid-resistant interstitial pneumonitis associated with Sjögren's syndrome.

Cyclosporin is known to be effective for both transplantation and a spectrum of immune-mediated diseases. Because this agent also causes severe adverse effects, especially nephrotoxicity, careful monitoring is required for the development of such reactions. Here we report the successful treatment with extremely low-dose cyclosporin (1 mg/kg/day) of a patient who had steroidresistant interstitial pneumonitis and Sjögrens syndrome.