Heparin-Related Thrombocytopenia Triggered by Severe Status of Systemic Lupus Erythematosus and Bacterial Infection.

A patient with severe lupus nephritis developed thrombocytopenia during treatment with high-dose steroids. In addition to viral- or disease-induced cytopenia, the pathology was believed to arise from diverse contributing factors, such as thrombotic microangiopathy and heparin-related thrombocytopenia (HIT). By combining plasma exchange therapy and intravenous cyclophosphamide, we successfully controlled the SLE activity and improved the thrombocytopenia. An antecedent bacterial infection or SLE activity is believed to have contributed to the concurrent HIT.

Elevated serum level of circulating syndecan-1 (CD138) in active systemic lupus erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE) is characterized by loss of B cell tolerance and by the presence of polyclonal B cell activation. Syndecan-1 (CD138) is expressed on plasma cells derived from B cells, and is suspected to play a role in SLE. We evaluated the level of soluble CD138 (sCD138) and cell surface expression of CD138 in patients with active SLE, and also examined correlations among the serum levels of BAFF, a proliferation-inducing ligand (APRIL), and CD138 in these patients. METHODS: Peripheral blood samples were obtained from 22 SLE patients in an active disease state and 14 normal controls. The levels of serum sCD138, sBAFF, and sAPRIL were measured using ELISA, and cell surface CD138 was analyzed by flow cytometry. The levels of CD138 mRNA were analyzed by RT-PCR. Blood samples were obtained longitudinally when the patients were in an inactive disease state. RESULTS: The levels of circulating CD138, CD138 mRNA in PBMC, and the numbers of CD20(- )CD38(+)CD138(+) plasma cells were increased in patients with active SLE in comparison with normal controls. Furthermore, the serum sCD138 level in SLE patients was found to correlate with the proportion of CD20(- )CD38(+)CD138(+) plasma cells. On the other hand, patients with active SLE showed a reduced level of sCD138, and this was inversely correlated with the serum level of sAPRIL. CONCLUSIONS: These results suggest that sCD138 may be applicable as a surrogate marker of disease activity, and that syndecan-1/APRIL signaling may be a potential therapeutic target for patients with active SLE.

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.

[Examination of availability of the criteria for protective therapy against Pneumocystis pneumonia].

Twenty patients with collagen diseases complicated with Pneumocystis pneumonia (PCP) were retrospectively examined in reference to the criteria for its protective therapy provided by the Ministry of Health Labor and Welfare. The breakdown of 20 patients was rheumatoid arthritis (RA) in 5 cases, systemic lupus erythematosus (SLE) in 5, dermatomyositis (DM) in 2, systemic scleroderma (SSc) in 1, mixed connective tissue disease (MCTD) in 1, Sjögren syndrome (SjS) in 1, polyarteritis nodosa (PN) in 3, rapidly progressive glomerulonephritis (RPGN) in 1, Schönlein-Henoch purpura in 1. Patients having interstitial pneumonia (IP) or renal dysfunction before acquiring PCP showed poor prognosis. High level of beta-D glucan was observed in all patients, and elevated levels of LDH and KL-6 were also characteristic of PCP. For the treatment of their own collagen diseases, high dose steroids had been given in 11 patients (55%), and immunosuppressive agents in 12 (60%), resulting in severe suppression of immune function in these patients. They were treated with Sulfamethoxazole/trimethoprim (ST) after Pneumocystis infection, however, 10 patients died and 8 of them died of respiratory failure in spite of high dose steroids. Nine patients fulfilled the criteria for PCP protective therapy provided by Ministry of Health Labor and Welfare, and 7 of them died of respiratory failure. The frequency of PCP remarkably decreased in our hospital after we had started the protective therapy with ST using the criteria, suggesting that it is effective for the protection of PCP. However, some patients who do not fulfill the criteria may acquire severe PCP.

Decrease in CD4+CD25+ and CD8+CD28+ T cells in interstitial pneumonitis associated with rheumatic disease.

The expression of CD25 or CD28 on T cells was examined in patients with rheumatic diseases associated with interstitial pneumonitis (IP), in order to investigate the conditions of CD4+CD25+ regulatory T cells and CD8+CD28- suppressor T cells. Fifty-five patients with various rheumatic diseases and 23 normal controls were enrolled. CD4+CD25+ T cells of patients with IP were significantly decreased in comparison with non-IP patients, and the ratio of CD8+CD28- T cells in patients with IP was significantly higher than that in non-IP patients or normal controls. These results for CD8+CD28- T cells were in accord with the decrease in CD8+CD28+ T cells, and may be related to activation-induced CD8+CD28+ T-cell death. Thus, the abnormality of CD4+CD25+ regulatory T cells may be related to the pathogenesis of IP, and the survival and activation of CD8+ T cells.

Expression of CD22 on peripheral B cells in patients with rheumatoid arthritis: relation to CD5-positive B cells.

B cells in patients with rheumatoid arthritis (RA) are hyperactivated. Although B cell receptor signal transduction may be affected by various response regulators, CD22 plays an important role as a response regulator of B cells. Therefore, we investigated and examined CD22 expression on peripheral blood B cells of patients with RA. Thirty-two RA patients and 16 controls were enrolled in this study, and CD22 expressions on B cells were analyzed by flow cytometry. In patients with RA, CD22(+) B cells significantly decreased in comparison to the controls (ratio: P < 0.05). However, there was no correlation between this decrease and the clinical data. Interestingly, CD5(+) CD22(-) B cells significantly increased in RA patients. The decrease in CD22(+) B cells and increased in CD5(+)CD22(-) B cells play critical roles in the pathogenesis of RA mediated by the activation of B cells.

Down-regulation of CD72 and increased surface IgG on B cells in patients with lupus nephritis.

The significance of both the acceleratory and inhibitory functions of the CD72 molecule was investigated among patients with systemic lupus erythematosus (SLE) during modification of B cell differentiation. Expression of the CD72 molecule and mRNA on B cells was decreased in SLE with lupus nephritis, while CD100 expression on both CD4+ T cells and CD8+ T cells was not significant in comparison with the controls. When the relationship between CD72 expression and other B cell markers was examined, decreased expression of CD72 was associated with differences in the stage of differentiation. In patients with decreased expression of CD72, switching to IgG was evident, and the disease stage was started to severe. In patients with lupus nephritis, the decreased expression of CD72 was related to class switching on B cells, suggesting that CD72 is a useful marker for determining class switching of B cells in lupus nephritis.