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Natalizumab, which is an antibody against α4 integrin, has been used for the treatment of multiple sclerosis. In the present study, we investigated both the role of α4 integrin and the therapeutic effect of HCA3551, a newly synthesized orally active small molecule α4 integrin antagonist, in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). The mRNA levels of α4 integrins were significantly up-regulated in the central nervous system (CNS) of mice with TMEV-IDD as compared with naive mice (*P < 0.05). HCA3551 treatment in the effector phase significantly suppressed both the clinical and histological development of TMEV-IDD. The number of infiltrating mononuclear inflammatory cells in the CNS was significantly decreased in the mice treated with HCA3551 (**P < 0.01). The labeling indices for CD68 antigen and the absolute cell numbers of TNF-α-producing CD4+ T cells and IFN-γ-producing CD8+ T cells were significantly decreased in the CNS of mice treated with HCA3551 (*P < 0.05). HCA3551 treatment in the effector phase might inhibit the binding of α4 integrin to vascular cell adhesion molecule-1, thereby decreasing the number of mononuclear cells in the CNS.

It was reported that 2,4-dichlorophenoxyacetic acid (2,4-D), a commonly used herbicide and a possible endocrine disruptor, can disturb spermatogenesis, but the precise mechanism is not understood. Since 2,4-D is a weak peroxisome proliferator in hepatocytes and peroxisome proliferator-activated receptor α (PPARα) is also expressed in Leydig cells, this study aimed to investigate the link between PPARα and 2,4-D-mediated testicular dysfunction. 2,4-D (130 mg/kg/day) was administered to wild-type and Ppara-null mice for 2 weeks, and the alterations in testis and testosterone/cholesterol metabolism in Leydig cells were examined. Treatment with 2,4-D markedly decreased testicular testosterone in wild-type mice, leading to degeneration of spermatocytes and Sertoli cells. The 2,4-D decreased cholesterol levels in Leydig cells of wild-type mice through down-regulating the expression of 3-hydroxy-3-methylglutaryl coenzyme A synthase 1 and reductase, involved in de novo cholesterogenesis. However, the mRNAs encoding the important proteins involved in testosterone synthesis were unchanged by 2,4-D except for CYP17A1, indicating that exhausted cholesterol levels in the cells is a main reason for reduced testicular testosterone. Additionally, pregnancy rate and the number of pups between 2,4-D-treated wild-type male mice and untreated female mice were significantly lower compared with those between untreated couples. These phenomena were not observed in 2,4-D-treated Ppara-null males. Collectively, these results suggest a critical role for PPARα in 2,4-D-induced testicular toxicity due to disruption of cholesterol/testosterone homeostasis in Leydig cells. This study yields novel insights into the possible mechanism of testicular dysfunction and male infertility caused by 2,4-D.

Co-sleeping and breastfeeding in the side-lying position have recently been pointed out as risk factors for suffocation in sleeping infants; however, there is no actual report on an "incident." "Incident" is defined as a tense or sobering experience without a consequential fatal suffocation accident. It is important to understand infant suffocation incidents to prevent accidents during co-sleeping and breastfeeding in the side-lying position. We investigated factors and frequency of infant suffocation incidents associated with co-sleeping and breastfeeding in the side-lying position using a self-administered questionnaire survey of 895 mothers during their infant's 1-, 4-, or 10-month health checkups. Co-sleeping and breastfeeding in the side-lying position were practiced by 28.3% and 56.0% of mothers, respectively; thus, 84.3% of the mothers surveyed were practicing either co-sleeping or breastfeeding in the side-lying position. Of those who received guidance from a medical professional, 36.1% practiced only co-sleeping while 60.1% practiced only side-lying breastfeeding. In the co-sleeping group, 10.6% had faced infant suffocation incidents, while 13.2% in the breastfeeding in the side-lying position group had faced similar incidents. Regarding factors associated with suffocation incidents while co-sleeping, the frequency of occurrence was significantly more in mothers of 1-month and 4-month-old infants compared with those of 10-month-old infants. Of mothers who faced suffocation incidents while breastfeeding in the side-lying position, 45% also had faced similar incidents while co-sleeping. These results demonstrate the importance of thoroughly educating mothers about the risks associated with co-sleeping and breastfeeding in the side-lying position for preventing infant suffocation.

Objective Myasthenia gravis (MG) is a T-cell dependent and antibody mediated autoimmune disease. Recent studies of adult patients and animal models have shown that regulatory T cells (Tregs) play an important role in the pathogenesis of MG, but little is known about MG in children. This study evaluated the role of peripheral blood Tregs in childhood ocular MG and assessed if Tregs could be an index for estimating immunological status. Patients and methods Clinical data and peripheral lymphocytes were obtained from 13 children with serum AChR antibody-positive ocular type MG and 18 age-matched controls. Committed cells from MG patients were divided into two clinical stages: active ( n = 12) and remission ( n = 11). Tregs and Th17 cells were analyzed by flow cytometric analysis based on CD4 + CD25 + intracellular Foxp3 + and CD4 + intracellular IL-17A + fractions, respectively. Results The percentage of Tregs among peripheral blood CD4 + T cells in active stage, remission stage, and control groups was 3.3 ± 1.3%, 4.8 ± 1.7%, and 5.0 ± 0.6%, respectively. The Treg population was significantly lower in the active stage than in the remission stage and controls. Furthermore, Treg percentage was significantly lower during relapse of myasthenia symptoms. We witnessed no remarkable associations between the percentage of Tregs and immune suppressant dosages. Conclusions A significant reduction in the peripheral Treg population is considered to contribute to the pathophysiology of ocular type childhood MG and may be a marker of immunological state in these patients.

Dimethyl fumarate (DMF) is a modifier of the nuclear factor (erythroid-derived 2)-2 (Nrf2)-kelch-like ECH-associated protein 1 (Keap1) pathway. DMF treatment in the effector phase significantly suppressed the development of Theiler’s murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) both clinically and histologically. DMF treatment leads to an enhanced Nrf2 antioxidant response in TMEV-IDD mice. DMF treatment in the effector phase significantly suppressed the level of IL-17A mRNA. DMF is known to inhibit differentiation of T helper 17 (Th17) cells via suppressing NF-κB. Taken together, our data suggest that DMF treatment in the effector phase may suppress TMEV-IDD not only via enhancing the antioxidant response but also via suppressing IL-17A.

Infection by Theiler’s murine encephalomyelitis virus (TMEV) in the central nervous system (CNS) induces an immune-mediated demyelinating disease in susceptible mouse strains and serves as a relevant infection model for human multiple sclerosis. T-cell immunoglobulin and mucin domain-3 (TIM-3) has been demonstrated to play a crucial role in the maintenance of peripheral tolerance. In this study, we examined the regulatory role of the TIM-3 pathway in the development of TMEV-induced demyelinating disease (TMEV-IDD). The expression of TIM-3 was increased at both protein and mRNA levels in the spinal cords of mice with TMEV-IDD compared with naive controls. In addition, by utilizing a blocking mAb, we demonstrate that TIM-3 negatively regulates TMEV-specific ex vivo production of IFN-γ and IL-10 by CD4+ T cells and IFN-γ by CD8+ T cells from the CNS of mice with TMEV-IDD at 36 days post-infection (dpi). In vivo blockade of TIM-3 by using the anti-TIM-3 mAb resulted in significant exacerbation of the development of TMEV-IDD both clinically and histologically. The number of infiltrating mononuclear cells in the CNS was also increased in mice administered with anti-TIM-3 mAb both at the induction phase (10 dpi) and at the effector phase (36 dpi). Flow cytometric analysis of intracellular cytokines revealed that the number of CD4+ T cells producing TNF, IL-4, IL-10 and IL-17 was significantly increased at the effector phase in the CNS of anti-TIM-3 mAb-treated mice. These results suggest that the TIM-3 pathway plays a critical role in the regulation of TMEV-IDD.

Aim Treatment cost is one of the biggest concerns for cancer patients. Providing information to cancer patients about treatment cost and available financial support contributes to high-quality care. The aim of this study was to determine chemotherapy costs and other medical care expenditures for patients with cervical and endometrial cancer. Methods Data from the Diagnosis Procedure Combination system, which is the Japanese version of the Diagnosis-related Group system, were used to identify 179 patients with cervical cancer and 244 patients with endometrial cancer who received chemotherapy from 2008–2010 at a specialized cancer hospital. The costs of chemotherapy per bolus, various protocols, and other medical care expenditures were investigated. Results The cost per bolus of chemotherapeutic agents varied from ¥13,804–258,906 ($US 173–3236). The total medical cost for each course, including supportive care and treatment for chemotoxic symptoms, ranged ¥22,230–590,140 ($US 278–7377). Fourteen protocols were used in this population. Multiple regression analysis revealed that the factors related to the total medical care cost for cervical cancer were cost of chemotherapeutic agents, laboratory tests, oral medications, number of complications, and age. For endometrial cancer, cost of chemotherapeutic agents, laboratory tests, and oral medications were the factors related to the total medical care costs. Conclusion The cost of various chemotherapy protocols and the total medical care was determined using the Diagnosis Procedure Combination system. Nurses should give the information about treatment cost and discuss the cost with patients to facilitate high-quality care.

Large granular lymphocytes (LGL) of the natural killer (NK) cell lineage were highly purified and their interleukin 2 (IL 2) receptors (IL 2R) were investigated in childhood acute lymphoblastic leukemia (ALL). Not only NK activity but also 3-day recombinant IL 2-cultured lymphokine activated killer (LAK) activity were decreased in ALL, despite normal percentages of LGL, CD16 (Leul1)(+) and CD56 (NKH1)(+) cells. The cytotoxic activity of IL 2-cultured LGL, but not IL 2-cultured T cells, was significantly decreased in ALL, indicating a selective defect of LGL among the killer cells. IL 2R (CD25) numbers/cell of 3-day IL 2-cultured LGL were not decreased in ALL by flow cytometric analysis. Scatchard plot analysis demonstrated that high affinity IL 2R numbers/cell of 3-day IL 2-cultured LGL were normal but the binding affinity level of the receptors in these cells in ALL was one-third of that in the similarly-cultured control cells, suggesting inadequate IL 2-IL 2R interaction is responsible, at least in part, for their reduced cytotoxic activity.

There have been no reports of human herpesvirus-6 (HHV-6) encephalitis treatment based on both HHV-6 DNA load and the antiviral agent's concentration in the cerebrospinal fluid (CSF).A 20-year-old male with a hematological malignancy developed HHV-6 encephalitis 15 days after unrelated cord blood transplantation (UCBT). He had fever, chest pain, memory impairment, and insomnia. His CSF showed no increased cell counts, but the amount of HHV-6 DNA was elevated to 2.0 × 10(6) copies/ìgDNA. Magnetic resonance imaging (MRI) of the head revealed abnormal high-intensity signals in the left limbic system on T2-weighted and diffusion-weighted images. Intravenous administration of ganciclovir (GCV) was initiated at 5 mg/kg every 12 h on day 18, and was continued until day 137. The amount of HHV-6 DNA in the plasma became undetectable on day 25. The HHV-6 load in the CSF decreased to 1.5 × 10(3) copies/ìgDNA on day 32, and reached undetectable levels on day 53. The mean concentration of GCV 1 h after an infusion of 5 mg/kg was 4.12 mg/mL in plasma and 0.7 mg/mL in CSF. The chest pain and insomnia disappeared on days 35 and 47, respectively. Memory defects recovered up to day 85.Serial quantification of HHV-6 DNA in CSF may be useful for successful treatment with GCV in post-transplant HHV-6 encephalitis.

We report a six-year-old girl with seizures induced by both micturition and defecation. Several days after unprovoked generalised tonic-clonic seizures, she developed reflex seizures characterised by the extension of both arms and rhythmic jerking of her upper body. No abnormal findings were noted on brain magnetic resonance imaging. Interictal electroencephalography (EEG) showed spike-and-wave activity on central electrode recording, and rhythmic fast activity was recorded by central electrodes during the ictal EEG upon micturition. The combination of clobazam and phenytoin was effective for both unprovoked and reflex seizures. Although some previous reports have described reflex seizures triggered by either micturition or defecation, this is the first case report of reflex seizures induced by both micturition and defecation in the same patient. Based on a comparison with previous cases of reflex seizures induced either by micturition or defecation, the neuronal pathway from the pelvic base musculature to the supplementary motor area may be responsible for the condition in our patient.

Background: The present study was designed to examine whether serum uric acid (SUA) levels were associated with cardiometabolic risk factors and to determine optimal cut-offs for SUA to identify multiple risk factors among Japanese junior high school students. Methods and Results: A total of 958 students (518 boys and 440 girls, aged 12.1-15.0 years) who were enrolled between April 2005 and June 2008 were divided into 4 groups according to SUA quartiles. Compared with the lowest quartile of SUA, prevalence of abdominal obesity, hypertension, and dyslipidemia was significantly increased in the highest quartile in boys and that of abdominal obesity was increased in the highest quartile in girls. The adjusted odds ratios (95% confidence interval) of the highest quartile of SUA for 2 or more cardiometabolic risk factors were 2.59 (1.16-5.79) for boys and 1.54 (0.43-5.56) for girls. Receiver operating characteristic curve analysis demonstrated that the most appropriate cut-offs for SUA to identify multiple cardiometabolic risk factors were 6.4 mg/dl for boys and 4.9 mg/dl for girls. Conclusions: SUA was strongly associated with the prevalence of cardiometabolic risk factors among male Japanese junior high school students. The present study may provide insights into the role of SUA in the school screening system for the development of educational programs on prevention of lifestyle-related diseases among school children. (Circ J 2010; 74: 1570 - 1577)

The pathogenetic mechanisms of the central nervous system (CNS) problems associated with Langerhans cell histiocytosis (LCH) are not well established. Effective treatment strategies for these CNS complications are not yet available, while diabetes insipidus, also associated with LCH, can be managed effectively. Three Japanese boys with LCH who developed cerebellar ataxia were evaluated. Similar pediatric cases from the literature are also discussed. All three patients initially developed multifocal LCH lesions during early childhood (age

Programmed death-1 (PD-1) belongs to the CD28 family of co-stimulatory and co-inhibitory molecules and regulates adaptive immunity. This molecule induces the development of regulatory T cells, T cell tolerance, or apoptosis. We examined the role of PD-1 pathway in Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease (TMEV-IDD) mice. Up-regulation of PD-1 and PD-1 ligand-1 (PD-L1) mRNA expression in bone marrow-derived dendritic cells were induced by TMEV infection in vitro. Furthermore, PD-1 and PD-L1 mRNA expression was increased in the spinal cords of the TMEV-infected mice in vivo. Treatment with a blocking monoclonal antibody (mAb) against PD-1, especially during the effector phase, resulted in significant deterioration of the TMEV-IDD both clinically and histologically. Flow cytometric analysis revealed a dramatically increase of CD4+ T cells producing Th1 cytokines such as IFN-γ and TNF-α in the spinal cord of anti-PD-1 mAb-treated mice. These results indicate that the PD-1 pathway plays a pivotal regulatory role in the development of TMEV-IDD.

Chronic relapsing-remitting experimental autoimmune encephalomyelitis (CREAE) induced with myelin oligodendrocyte glycoprotein peptides 35-55 (MOG(35-55)) in NOD mice was successfully treated with brain-derived gangliosides (GA). The GA treatment suppressed the development and severity of CREAE, both clinically and histologically. Spleen cells from the GA-treated mice displayed markedly inhibited levels of MOG(35-55) specific proliferation and interferon-gamma production. Delayed-type hypersensitivity reactions to MOG(35-55) were suppressed by the GA treatment. GA modulate various T cell effector functions in CREAE and may be an effective therapeutic agent for autoimmune demyelinating diseases such as multiple sclerosis.

Previous studies have shown that activation of blood coagulation and fibrin depositions around CNS vessels are observed in animals with experimental autoimmune encephalomyelitis (EAE), which provides an animal model for human autoimmune demyelinating disorders. We examined the values of peripheral blood fibrinogen, thrombin-antithrombin III complex (TAT), fibrinolytic activity, and fibrin degradation products in Lewis rats with EAE to elucidate the role of the blood coagulation-fibrinolysis system in EAE. Plasma TAT values increased immediately prior to development of symptoms, and decreased according to the improvement of symptoms. There was significant correlation between TAT values and clinical scores of EAE; other markers were not correlated with the symptoms of EAE. These results suggest that plasma TAT levels are sensitive markers of the severity of EAE, and may be useful clinical indicators for the severity of human autoimmune demyelinating disorders.

Background/Aims: The imbalance between degradation and synthesis of the glomerular extracellular matrix (ECM) causes glomerular sclerosis in various types of glomerulonephritis. We investigated the effect of prostacyclin, which is an inflammatory mediator, on the production of matrix metalloproteinase (MMP)-9 and MMP-2 in human cultured mesangial cells. The synthesis of Jun proteins and Ets-1 proteins, which are related with MMP-9 gene, was also studied. Methods: The production of MMP-9 and MMP-2 was investigated by gelatin zymography. Western blotting was undertaken to analyze the protein synthesis of Jun and Ets-1. Results: Prostacyclin inhibited the production of MMP-9 induced by phorbol ester. The inhibitory effect by prostacyclin was reversed in part by the pretreatment with an inhibitor of protein kinase A, such as H-89. Forskolin also inhibited the production of MMP-9. The production of MMP-2 was constitutionally seen and was not influenced by prostacyclin and forskolin. The synthesis of Jun protein augmented by phorbol ester was suppressed by prostacyclin. Ets-1 protein was constitutionally synthesized and was not affected by phorbol ester and prostacyclin. Conclusion: Prostacyclin plays an important role in inflammatory glomerular disorders by regulating the metabolism of ECM. The production of MMP-9 and MMP-2 may be under the different control pathways.

The effect of dermatan sulfate (DS) on the treatment of Lewis rats with experimental autoimmune encephalomyelitis (EAE) was examined. DS, a sulfated glycosaminoglycan, has been reported to exhibit anticoagulant and fibrinolytic activities. DS treatment (50 mg/kg/day) facilitates recovery from the clinical manifestations of EAE. In this study, the fibrinolytic activity was higher in DS-treated rats than in saline-treated rats. Although the degree of perivascular mononuclear cell infiltration in the spinal cord was not suppressed in DS-treated rats compared to that in saline-treated rats, perivascular fibrin deposition was markedly suppressed in DS-treated rats. These findings suggest that DS would act as an effective therapeutic agent for EAE by preventing fibrin deposition.

We have recently shown that a single dose of the myelin oligodendrocyte glycoprotein (MOG) peptide 35-55 produces a relapsing–remitting demyelinating disease similar to multiple sclerosis (MS) in Lewis rats. In this study we have assessed the possibility that a subclass of anti-MOG 35-55 antibodies influences the clinical outcome of these diseases by examining the classes and isotypes of anti-MOG 35-55 antibody produced during the course of MOG 35-55 -induced demyelinating disease in NOD mice. Following immunization, 7 of the 21 injected mice had only mild diseases, while the 14 others had severe progressive and/or relapsing–remitting diseases. There were no differences in anti-MOG 35-55 IgG, IgA, IgM, IgG1, IgG2a, and IgG3 antibody titers between the severe and mild symptoms groups. High levels of IgG2b antibody to MOG 35-55 were detected in all mice with severe symptoms. In contrast, none of the mice which contracted a mild disease produced anti-MOG 35-55 IgG2b. These results suggest that in NOD mice, the IgG2b antibody response to MOG 35-55 is associated with the severity of this MS-like demyelinating disease.

We described an 11 year-old boy with systemic lupus erythematosus (SLE) and various coagulopathy. He had purpura on the legs, pancytopenia, positive anti-DNA antibodies and hypocomplementia. Hematological examination also showed that platelet counts were 80 x 10(3)/microliter, lupus anticoagulant and anticardiolipin antibodies were positive. The aPTT was remarkably prolonged. Those laboratory findings fulfilled the criteria of antiphospholipid syndrome. Following treatment with predonisolone and heparin, thrombocytopenia improved. When heparin discontinued and renal biopsy was performed, severe thrombocytopenia recureded. FDP and FDP-DD became high, but the aPTT was not prolonged. Thrombocytopenia didn't improved by the therapy with heparin, high dose of methylpredonisolone, FOY and gamma-globulin. However by the therapy with both warfarin and cyclophosphamide, remarkable improvement of coagulopathy was absorbed. Probably anticardiolipin antibodies and disseminated intravascular coagulation (DIC) participate in the various coagulopathy in this case.

We examined the role of leukocyte function-associated antigen (LFA)-1 and its counter-receptor intercellular adhesion molecule (ICAM)-1, one of the most important pairs of adhesion molecules, in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Immunohistochemical study showed hyper-expression of ICAM-1 on vascular endothelial cells and expression of LFA-1 on mononuclear infiltrating cells in the spinal cords of TMEV-infected mice. Treatment with mAb to ICAM-1 and/or LFA-1 molecules resulted in significant suppression of the development of demyelinating disease, both clinically and histologically, with down-regulation in the CNS of the respective adhesion molecules after treatment. In mice treated with these mAb, the specific delayed-type hypersensitivity and T cell proliferative responses for TMEV were decreased. The production of tumor necrosis factor-alpha and IFN-gamma in spleen cells was also decreased, but IL-4 production remained unchanged. These data suggest that ICAM-1/LFA-1 interaction is critically involved in the pathogenesis of TMEV-IDD and that antibodies to these adhesion molecules could be a novel therapeutic approach to the treatment of demyelinating diseases such as human multiple sclerosis.

We examined the regulatory role of αv integrins in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD), a model of multiple sclerosis (MS). Blockade of αv integrins by anti-αv integrin monoclonal antibody (mAb) in the effector phase significantly suppressed the development of TMEV-IDD both clinically and histologically. The number of infiltrating mononuclear cells (MNCs) in the CNS was significantly decreased in mice treated with anti-αv integrin mAb. Flow cytometric analysis of cytokine staining revealed that absolute numbers of IFN-γ- and IL-17-producing CD4+ and IFN-γ-producing CD8+ T cells were significantly decreased in the CNS of mice treated with anti-αv integrin mAb. These data suggest that αv integrins may play important roles in the development of TMEV-IDD.

Multiple sclerosis (MS) is a chronic demyelinating disease often displaying a relapsing-remitting course of neurological manifestations that is mimicked by experimental autoimmune encephalomyelitis (EAE) in animal models of MS. In particular, NOD mice immunized with myelin oligodendrocyte glycoprotein peptide 35-55 develop chronic relapsing-remitting EAE (CREAE). To elucidate the mechanisms that cause MS relapse, we investigated the histopathology and cytokine production of spleen cells and mRNA expression levels in the central nervous system (CNS) of CREAE mice. During the first attack, inflammatory cell infiltration around small vessels and in the subarachnoid space was observed in the spinal cord. Spleen cell production and mRNA expression in the CNS of several cytokines, including IFN-γ, TNF-α, IL-6, IL-17, and CC chemokine ligand 2 (CCL2), were higher in CREAE mice than in controls. Afterwards, parenchymal infiltration and demyelination were observed histologically in the spinal cord and corresponded with the more severe clinical symptoms of the first and second relapses. IL-17 and CCL2, but not IFN-γ, TNF-α, or IL-6, were also produced by spleen cells during recurrences. Our results suggested that the immune mechanisms in relapses were different from those in the first attack for CREAE. Further investigation of CREAE mechanisms may provide important insights into successful therapies for human relapsing-remitting MS.

Several immune mechanisms are suspected in the unknown etiology of West syndrome (WS). We report a male infant who suffered from WS and X-linked T-B+NK- severe combined immunodeficiency (X-SCID) with a missense mutation of the IL2RG gene (c.202G>A, p.Glu68Lys). He promptly began vitamin B6 and valproic acid treatment, but infantile spasms (IS) and hypsarrhythmia persisted. Administration of intravenous immunoglobulin and the change to topiramate (TPM) at 7 months of age resulted in the rapid resolution of IS. The CD4/8 ratio in his peripheral blood increased from 0.04-0.09 to 0.20-1.95 following unrelated cord blood transplantation (UCBT). In vitro lymphocyte proliferation in response to phytohemagglutinin or concanavalin A and the ability of B lymphocytes to produce antibodies improved as well. Electroencephalogram findings became normal 1 month after UCBT. Thus, we consider that T-cell dysfunction and/or impairments in T-B cell interactions due to X-SCID may have played important roles in the onset of WS. Immune-modulating therapies along with the administration of TPM effectively treated this severe epileptic syndrome in our patient.

Previous studies from our laboratory have demonstrated a predominant response to myelin oligodendrocyte glycoprotein (MOG) in patients with multiple sclerosis (MS) and showed that this molecule is able to induce in Lewis rats a chronic relapsing MS-like disease with extensive demyelination. To further study the possibility that MOG is a primary target antigen in MS, we have begun to investigate the encephalitogenicity and antibody response of different sequences of the extracellular domains of MOG in Lewis rats. We report that none of the synthetic peptides encompassing the MOG amino acid sequences 1-21, 67-87, 104-117 and 202-218 were encephalitogenic. In contrast, a single injection of MOG35-55 was able to induce severe neurological signs associated with inflammation and demyelination. All rats injected with MOG peptides 1-21, 35-55, 67-87 and 202-218 developed a high level of antibodies to their respective immunizing peptides as detected by ELISA and immunoblotting. Although all MOG peptide antisera reacted with immunoblots of native MOG separated under reducing conditions, only anti-MOG35-55 and anti-MOG202-218 antibodies reacted to native MOG, when tested under nonreducing conditions. These results indicate that the MOG35-55 peptide, which is found in the extracellular Ig V-like domain of MOG, is not only an encephalitogenic epitope but could also be an important determinant for initiating antibody-mediated demyelination. As indicated by the absence of reactivity to the other MOG peptides tested, as well as other central nervous system myelin proteins including myelin basic protein and proteolipid protein, the antibody response produced by MOG peptides is highly restricted.

Characteristics of myelin basic protein (MBP)-induced experimental autoimmune encephalomyelitis (EAE) include acute edema and infiltration of mononuclear cells (MNCs) in the microvessels of central nervous system (CNS). Aquaporin-4 (AQP4) is a water channel protein expressed in astrocytes foot process throughout the CNS. We performed immunostaining, western blotting and semi-quantitative real-time RT-PCR of AQP4 and glial fibrillary acidic protein (GFAP) in CNS from rats immunized with MBP. Immunohistochemical analysis revealed that AQP4 is down-regulated in MNCs infiltrated microvessels of rats with EAE. Furthermore, western blotting and real-time RT-PCR analyses showed that AQP4 was significantly decreased at the stage of severe EAE compared with control rats. On the other hand, expression of GFAP-protein was significantly increased after stage of severe EAE. Our findings suggest that AQP4 may be involved in forming edema in the inflammatory lesions of EAE accompanying with up-regulation of reactive astrocyte.

Neoplastic cells of childhood acute lymphoblastic leukemia (ALL) with natural killer (NK) cell properties were studied for the expression of p75 interleukin-2 receptors (IL-2R) and the receptor functions. Freshly prepared blast cells from a patient with ALL had NK cell properties: (1) the phenotype such as CD56+, CD2+, E-rosette+, CD3-, and CD19-; and (2) the presence of spontaneous cytotoxicity against NK-sensitive K562 target cells. Although p55 Tac antigen was not detectable, there was the expression of p75 IL-2R on the freshly prepared blast cells: 70% of the cells reacted with Mik-beta 1 monoclonal antibody against p75 IL-2R as determined by flow cytometry. Two-color flow cytometry revealed that the blast cells expressed both p75 IL-2R and NKH-1. NK activity of the blast cells was augmented by their treatment with 1,000 U/ml recombinant IL-2 (rIL-2): the cytotoxicity level as percentage lysis increased to 38.7% from 22.0% when the normal lymphocyte value increased to 62.1% from 46.2%. Although the blast cells possessed no apparent level of proliferative capacity, the addition of 1,000 U/ml rIL-2 yielded a 2.7-fold increase in their thymidine uptake. These results demonstrate the expression of functional p75 IL-2R on the patient's blast cells with NK cell properties.

Myelin basic protein (MBP) can be used as an antigen for inducing experimental allergic encephalomyelitis (EAE). In various studies, EAE animals have been used as an experimental model of demyelinating diseases. The aim of this study was to determine whether EAE, induced by MBP in rats, can be useful for investigation of bladder dysfunction associated with demyelinating disease. Female Lewis rats were used. In Study 1, the time course of behavioral and cystometric changes were observed consecutively after MBP sensitization. In Study 2, the correlations between behavioral, cystometric, and histologic abnormalities were studied. The degree of paralysis and histologic findings were evaluated. In Study 1, transient hind limb paralysis was observed in all rats. Cystometric findings were characterized by three different patterns: 1) detrusor areflexia (DA), 2) detrusor hyperactivity (DH), and 3) normal. Ten (77%) of the 13 rats given MBP showed bladder dysfunction, including DA (seven), DA/DH (two) and DH (one). Study 2 showed DA in 10 rats, DH in one, and normal findings in nine animals. The difference in degree of paralysis between the DA and the cystometrically normal animals was statistically significant (P

Treatment with monoclonal anti-IL-12 antibody injected on day 0, 7 and 10 after immunization with myelin oligodendrocyte glycoprotein (MOG) peptide 35–55 in NOD mice resulted in significant suppression of the development and the severity of the chronic relapsing–remitting experimental autoimmune encephalomyelitis (EAE) both clinically and histologically. The spleen cells from anti-IL-12 antibody treated mice displayed markedly inhibited MOG35–55 specific proliferation and IFN-γ production. MOG35–55 specific antibody production was enhanced by anti-IL-12 antibody treatment. These results suggest that IL-12 is critically involved in the pathogenesis of MOG-induced EAE and that antibody to IL-12 could be an effective therapeutic agent in the clinical treatment of autoimmune demyelinating diseases such as multiple sclerosis (MS).

Myelin oligodendrocyte glycoprotein (MOG) is a member of the immunoglobulin superfamily expressed exclusively in central nervous system (CNS) myelin. While the function of MOG is unknown, a number of studies have shown that immune responses to MOG contribute to the autoimmune-mediated demyelination seen in animals immunized with whole CNS tissue. This paper summarizes our recent studies, which unequivocally demonstrate that MOG by itself is able to generate both an encephalitogenic T cell response and an autoantibody response in Lewis rats and in several strains of mice. In Lewis rats the injection of both native MOG and MOG35–55 peptide produces a paralytic relapsing-remitting neurological disease with extensive plaque-like demyelination. The antibody response to MOG35–55 was highly restricted, as no reactivity to either other MOG peptides or myelin proteins could be detected. Fine epitope mapping showed that antibody from serum and cerebrospinal fluid of injected rats reacted strongly to MOG37–46, which is contiguous to the dominant T cell epitope contained within MOG44–55. NOD/Lt and C57BL/6 mice were also susceptible to severe neurological disease following injection with recombinant MOG or MOG35–55 peptide, indicating that this specific CNS autoantigen, or some of its determinants, can induce a pathogenic response across animal species. Severe paralysis and extensive demyelination were seen in both strains, but NOD/Lt mice experienced a chronic relapsing disease whereas C57BL/6 mice had a chronic non-remitting disease. Moreover, transfer of MOG35–55 T cells into naive NOD/Lt mice also produced severe neurological impairment as well as histological lesions. These results emphasize that a synergism between a T cell-response and anti-MOG antibodies may be important for the development of severe demyelinating disease. This, together with our demonstration that there is a predominant T cell response to MOG in patients with multiple sclerosis, clearly indicates that MOG is probably an important target autoantigen in this disease.

Two patients with severe generalised myasthenia gravis of childhood were successfully treated with immunoadsorption plasmapheresis. One patient was a 5 year old girl and the other was a 12 year old girl. A dramatic improvement in bulbar symptoms and generalised muscle weakness was achieved without any side effects. Plasma exchange may also yield clinical improvement for myasthenia gravis, but the treatment is accompanied by the risk of viral infections and hypersensitivity reactions. Immunoadsorption plasmapheresis is an effective treatment for severe generalised myasthenia gravis of childhood and is superior to plasma exchange with respect to safety.

Recent reports have described clinical benefits of all-trans-retinoic acid (ATRA) therapy for acute promyelocytic leukemia (APL). This paper describes severe hypercalcemia (serum calcium: 18.7 mg/dl) in association with ATRA treatment in a 14 year old girl with APL. Serum parathyroid hormone (PTH) concentrations were normal (0.21 ng/ml), which precludes the possibility of primary hyperparathyroidism or ectopic PTH secretion as a cause of the hypercalcemia. As for the factors which can accelerate mineral resorption, there were no apparent increases in the levels of PTH-related protein (PTH-rP), prostaglandins and vitamin D metabolites. In our in vitro experiment, ATRA did not stimulate the leukemic cells to produce PTH-rP. We speculate that ATRA, like PTH, may increase osteoclastic activity and induce hypercalcemia.

Peripheral blood mononuclear cells (PBMC) from acute lymphoblastic leukemia (ALL) patients were studied for the expression of interleukin 2 receptors (IL-2R). When stimulated with phytohemagglutinin (PHA) for 3 days, the percentage of p55 Tac positive cells and the number of high affinity IL-2R was decreased in on-therapy ALL patients at remission and returned to normal after cessation of the treatment. However, the percentage of p75 IL-2R positive PBMC was normal in all ALL patients at remission. It is well-known that there are several immunological abnormalities including T and natural killer (NK) cell dysfunctions in ALL patients undergoing maintenance chemotherapy. IL-2 facilitates T-cell growth and corrects defective NK activity. Taking this into account, there may be a poor utilization of autologously produced IL-2 because of the impaired expression of IL-2R, and this poor utilization of IL-2 may be related to the defective immunological functions in childhood ALL patients at remission who are receiving maintenance chemotherapy.