Mikiko Tokunaga

Efficacy of rituximab (anti-CD20) for refractory systemic lupus erythematosus involving the central nervous system

Aim: Neuropsychiatric systemic lupus erythematosus (NPSLE) is a serious treatment-resistant phenotype of systemic lupus erythematosus. A standard treatment for NPSLE is not available. This report describes the clinical and laboratory tests of 10 patients with NPSLE before and after rituximab treatment, including changes in lymphocyte phenotypes. Methods: Rituximab was administered at different doses in 10 patients with refractory NPSLE, despite intensive treatment. Results: Treatment with rituximab resulted in rapid improvement of central nervous system-related manifestations, particularly acute confusional state. Rituximab also improved cognitive dysfunction, psychosis and seizure, and reduced the SLE Disease Activity Index Score at day 28 in all 10 patients. These effects lasted for >1 year in five patients. Flow cytometric analysis showed that rituximab down regulated CD40 and CD80 on B cells and CD40L, CD69 and inducible costimulator on CD4+ T cells. Conclusions: Rituximab rapidly improved refractory NPSLE, as evident by resolution of various clinical signs and symptoms and improvement of radiographic findings. The down regulation of functional molecules on B and T cells suggests that rituximab modulates the interaction of activated B and T cells through costimulatory molecules. These results warrant further analysis of rituximab as treatment for NPSLE.

Phenotypic changes of lymphocytes in patients with systemic lupus erythematosus who are in longterm remission after B cell depletion therapy with rituximab

Objective. Rituximab has recently emerged as a novel treatment strategy for systemic lupus erythematosus (SLE). We investigated longitudinally the differentiation and phenotypic changes of peripheral B cells and T cells in patients with SLE after rituximab treatment. Methods. Phenotypic changes on B cells and T cells in 10 patients with SLE treated with rituximab were analyzed before, 28 days after, and 2 years after rituximab treatment, and at relapse. Results. Rituximab rapidly depleted naive and memory B cells from the peripheral blood. In the patients with prolonged remission, the memory B cells remained depleted while naive B cells recovered within 3–9 months, and the expression levels of CD40 and CD80 remained downregulated for 2 years. There was also a decrease of memory T cells relative to naive T cells, and the expression of CD40L and inducible costimulator (ICOS) on CD4-positive T cells rapidly decreased and remained downregulated for 2 years. In 1 patient, an increase in the number of memory B cells with upregulation of CD40 and CD80 expression was noted just before relapse. In another patient with relapse, however, recovery of CD4-positive memory T cells with upregulation of ICOS expression was noted, with no change in the number of memory B cells. Conclusion. Our results suggest that the phenotypic changes of peripheral B cells result in inhibition of T cell differentiation and activation mediated by B cells and thereby bring about longterm remission of SLE. Activated memory B cells or ICOS-positive CD4-positive memory T cells reappeared in association with relapse, probably reflecting the heterogeneity of SLE.

C5a promotes migration, proliferation, and vessel formation in endothelial cells

ObjectivesThe goal of this paper is to investigate the effects of activated complement C5a on vascular endothelium during vessel formation.MethodsA human microvascular endothelial cell line (HMEC-1) derived from post-capillary venules in skin was used to measure DNA synthesis, proliferation and cell-cycle progression. In vitro ring-shaped formation by the cells was assessed by using type I collagen gel matrix and a cell-migration assay using the Chemotaxicell chamber. A Matrigel plug assay was performed to confirm the effect of C5a in vivo.ResultsC5a progressed the cell cycle of HMEC-1 into G2/M phases, and induced DNA synthesis and proliferation in a dose-dependent manner. C5a efficiently induced migration and ring-shaped structure formation both in vitro and in vivo. Furthermore, a C5a receptor antagonist (W-54011) suppressed all HMEC-1 activities including proliferation and migration.ConclusionsProliferation, migration, and ring-shaped formation by HMEC-1 cells was induced by C5a. The actions were efficiently inhibited by a specific antagonist against C5a. Our results implicated C5a in vessel formation and as a potent target for management of inflammatory diseases.

B cell or T cell-dominant recurrence after rituximab therapy in patients with SLE

Systemic lupus erythematosus (SLE) is an autoimmune disease induced by autoreactive T cell activation and B cell autoantibody overproduction. The efficacy of rituximab in refractory SLE has been documented, although some patients show partial response only.1,–,9 We report here two patients with SLE who showed T cell-dominant flare-up and two others who showed B cell-dependent flare-up, after long-term remission induced by rituximab administered at 375 mg/m2 twice/week. Rituximab rapidly depleted peripheral naive and memory B cells in patients with SLE. Patients with prolonged remission had persistent depletion of memory B cells for >2 years, whereas recovery of naive B cells occurred within 3–9 months. The expression levels of CD80 on B cells diminished rapidly and remained downregulated. Furthermore, CD69 and ICOS (inducible T-cell co-stimulator) expression levels on CD4+ T cells also decreased and remained at low levels.10 B cell-dominant recurrence occurred in two patients, who were concurrently positive for anti-ds-DNA antibodies and extractable nuclear antigen, with lupus nephritis (class II) before treatment …

Efficacy of mizoribine treatment in patients with SjÖgren’s syndrome: an open pilot trial

Abstract The aim of this study was to evaluate the efficacy and safety of mizoribine in patients with Sjögren’s syndrome. Forty patients with sicca syndrome, whose conditions were definitely diagnosed as Sjögren’s syndrome, were given mizoribine orally at a dosage of 150 mg/day for 12 months. The percentage change in salivary secretion after 3, 6, and 12 months of the therapy increased to +112.2% (P < 0.001), +119.9% (P < 0.01), and +147.3% (P < 0.001), respectively, compared with the baseline. Serum IgG levels decreased significantly throughout the study, and the level was 1969.4 ± 620.0 mg/dl after treatment for 12 months compared with the pretreatment value of 2094.3 ± 746.6 mg/dl (P < 0.05). The patient’s assessment of clinical signs and symptoms on a 10-cm visual analog scale improved significantly from 7.2 ± 2.3 cm at the start of the treatment to 5.0 ± 1.9 cm after 12 months (P < 0.001). There was a similar improvement in the physician’s assessment using the 10-cm visual analog scale: 7.1 ± 1.6 cm at the start of the treatment and 5.2 ± 1.9 cm after 12 months (P < 0.001). With regard to safety, no serious adverse reactions were observed. Although a controlled study would be required to clarify the efficacy of mizoribine, these preliminary observations indicate its efficacy for ameliorating glandular symptoms through improvements in immune abnormalities in patients with Sjögren’s syndrome.

Persistent memory B cell down-regulation after 6-year remission induced by rituximab therapy in patients with systemic lupus erythematosus

Sir, Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease induced by autoreactive T cell activation and autoantibody overproduction by B cells. Rituximab produces B cell depletion in patients with refractory SLE. However, the precise mechanism of rituximabinduced long-term SLE remission remains unknown. We investigated the phenotypic changes in lymphocytes in six patients with SLE refractory to high-dose corticosteroid and immunosuppressants including cyclophosphamide (four with lupus nephritis (WHO type I:1, type IV:3) and four with neuropsychiatric (NP)-SLE (two with both lupus nephritis and NP-SLE)). They had been in remission for 6 years since receiving rituximab. Patients’ numbers (#1, 2, 3, 4, 5, 7) and their clinical background were matchedwith those used in our previous study.Dose of rituximabwas 375mg/m every 2 weeks referred to therapeutic dose of lymphoma 375mg/m weekly (4– 8 weeks). Written informed consent was obtained from each patient and the study was approved by the ethics committee of our university. Figure 1A shows a representative patient with long-term remission (Patient #4). Rituximab resulted in the disappearance of peripheral blood CD19þIgDþCD27 naı̈ve B cells, CD19þ IgD CD27þ class-switched memory B cells and CD19þIgD CD27 memory B cells within 4 weeks. However, recovery of naı̈ve B cells occurred within 3–9 months and persisted for 2–6 years, whereas memory B and plasma cells remained depleted through 0.5–6 years. The disappearance of memory B and plasma cells was observed in all six patients with long-term remission of SLE. Rituximab increased CD19þIgDþCD27 naive B cells (mean SD: 42.0 18.0% to 86.5 5.8% (p< 0.05) to 87.8 5.2% (p< 0.05)) and reduced CD19þIgD CD27þ class-switched memory B cells (29.4 7.2% to 6.5 2.6% (p< 0.05) to 5.0 3.5% (p< 0.05)) and CD19þIgD CD27 memory B cells (26.9 15.3% to 5.9 3.0% (p< 0.05) to 5.7 3.2% (p< 0.05)) at 6 years after rituximab treatment. On the other hand, CD19þIgDþCD27þ memory B cells remained low at 6 years after treatment with rituximab (1.7 0.6% to 1.0 0.8% to 1.6 1.4%). Little is known about the origin of CD19þIgDþCD27þ memory B cells, which are thought to be related to splenic marginal-zone B cells since they have similar phenotypic markers with different requirements for Ig receptor mutation. During the same period, SLE remained in remission and the mean dose of corticosteroid was tapered from 35.0 to 2.9mg/day. We reported that rituximab therapy rapidly decreased CD19þ cells bearing CD80, but a significant reduction from baseline levels was still noted at 2 and 6 years in CD80-expressing cells among the CD19þ cells (59.9 30.4% to 9.8 5.4% (p< 0.05) to 9.6 2.9% (p< 0.05)) (Figure 1B). Furthermore, the number of CD4þ T cells (207 53.0 to 340 139.3 (p< 0.05) to 380.3 209.5 (p< 0.05) cells/ml) and CD45RO naı̈ve T cells (72.1 36.2 to 185 104.9 (p< 0.05) to 170 108.1 (p< 0.05) cells/ ml) increased significantly (Figure 1C) and the expression of costimulatory molecules CD40L (9.9 7.8% to 2.1 0.9% (p< 0.05) to 2.6 0.7% (p< 0.05)) and ICOS (9.6 4.9% to 2.7 1.8% (p< 0.05) to 3.3 1.6% (p< 0.05)) on CD4þ cells remained down-regulated at 2 and 6 years in the six rituximab-treated patients (Figure 1D). The above results indicate that rituximab induced characteristic phenotypic changes within 6 years in patients with remission: decrease in memory B cells, plasma cells, and CD80-positive B cells, increase in CD4þ naı̈ve, and decrease in CD40L and ICOS on CD4þ T cells. Taken together, we suggest that activated T cells, in addition to activated B cells, seem to be involved in the pathogenesis of SLE and that activated B T cell interaction may worsen the pathophysiology of SLE. B cell recovery following rituximab treatment in SLE is associated with a delay in peripheral blood memory B cell recovery that correlates with a reconstitution dominated by an expansion of naive B cells. The severely delayed maturation and/or expansion of memory B cells might, therefore, lead to the inhibition of T cell activation and Received 2 December 2012; accepted 12 January 2013 Correspondence to: Yoshiya Tanaka, The First Department of Internal Medicine, School of Medicine, University of Occupational & Environmental Health, Japan, 1–1 Iseigaoka, Yahata-nishi, Kitakyushu 807–8555, Japan. Email: tanaka@med.uoeh-u.ac.jp