Junichi Yata

Primary immunodeficiency syndrome in Japan. I. Overview of a nationwide survey on primary immunodeficiency syndrome

The results of a nationwide survey on primary immunodeficiency syndrome (PIS) in Japan are presented. By the repeated questionnaire method, 497 PIS cases were collected prior to February 1979 with clinical information. Numbers of each type of PIS, age at the time of diagnosis, patients status at the time of registration, familial incidence of PIS, and development of malignancy, autoimmune diseases, and allergic diseases among all reported patients are presented and discussed.

Anti-tumor activity of antizyme which targets the ornithine decarboxylase (ODC) required for cell growth and transformation.

Cell proliferation and transformation induced by growth factor stimulation or by carcinogens, viruses, or oncogenes are characterized by an associated increase in polyamine levels, which is mediated by increased polyamine biosynthesis and enhanced uptake of polyamines. Polyamine biosynthesis is catalyzed particularly, in the level of ornithine decarboxylase (ODC). The elevation of cellular polyamine levels on the other hand accelerates the induction of ornithine decarboxylase antizyme (antizyme), which is involved not only in ODC-degradation, but in the negative regulation of polyamine transport. Taking advantage of these characteristics of antizyme, the potential of antizyme as a factor having anti-cell growth and anti-tumor activity was investigated. We show that antizyme can induce cell death associated with a rapid decline of intracellular polyamine contents. The possible anti-tumor activities of ectopically expressed antizyme were tested in p21H-ras (Val 12)-transformed NIH3T3 cells and several human malignant cell lines including a line with loss of p53 expression, and they were shown to be as sensitive as nontransformed NIH3T3 cells in vitro. The in vivo anti-tumor activity was also tested using nude mice inoculated with H-ras transformed NIH3T3 cells that had been transfected with inducible antizyme expression vector and the results showed that antizyme expression in vivo blocks tumor formation in these mice. These results suggest that ectopic antizyme expression is of possible therapeutic benefit in the treatment of cancer, which is mediated by ODC inactivation and intracellular polyamine depletion.

Ku in the cytoplasm associates with CD40 in human B cells and translocates into the nucleus following incubation with IL-4 and anti-CD40 mAb.

CD40 plays a critical role in survival, growth, differentiation, and class switching of B lymphocytes. Although Ku is required for immunoglobulin class switching, how CD40 signal transduction is coupled to Ku is still unknown. Here, we show that CD40 directly interacts with Ku through the membrane-proximal region of cytoplasmic CD40. Ku was confined to the cytoplasm in human primary B cells, and the engagement of CD40 on the B cells cultured in the presence of IL-4 resulted in the dissociation of Ku from CD40, translocation of Ku into the nucleus, and increase in the activity of DNA-dependent protein kinase. These findings indicate that Ku is involved in the CD40 signal transduction pathway and may play an important role in the CD40-mediated events.

Hematopoietic stem cell transplantation for 30 patients with primary immunodeficiency diseases: 20 years experience of a single team.

We retrospectively analyzed our results of 30 patients with three distinctive primary immunodeficiency diseases (PIDs) – severe combined immunodeficiency (SCID, n=11), Wiskott–Aldrich syndrome (WAS, n=11) and X-linked hyper-immunoglobulin M (IgM) syndrome (XHIM, n=8) – who underwent hematopoietic SCT (HSCT) during the past 20 years. Until 1995, all donors were HLA-haploidentical relatives with T-cell depletion (TCD) (n=8). Since 1996, the donors have been HLA-matched related donors (MRD) (n=8), unrelated BM (UR-BM) (n=7) and unrelated cord blood (UR-CB) (n=7). Twenty-seven of 30 patients had various pre-existing infections with or without organ damages before HSCT. Conditioning regimen and GVHD prophylaxis were determined according to disease, donor and pretransplant status. Although one of eight patients transplanted with TCD is alive with full engraftment, the other seven died. On the other hand, 18 of 22 patients transplanted without TCD are alive and well, including six of eight transplanted from MRD, seven of seven from UR-BM and five of seven from UR-CB. All 19 survivors did not require Ig supplementation after HSCT. These results indicate that UR-CBT as well as UR-BMT provides good results for PID comparable to MRD-SCT, and that early diagnosis, HSCT at early stage, careful supportive therapy and monitoring for various pathogens are important for the successful HSCT.

WASP is involved in proliferation and differentiation of human haemopoietic progenitors in vitro

The Wiskott‐Aldrich syndrome (WAS) is an X‐linked recessive disorder characterized by thrombocytopenia, immunodeficiency and eczema. X‐linked thrombocytopenia (XLT) is a mild form of WAS with isolated thrombocytopenia. Both phenotypes are caused by mutation of the Wiskott‐Aldrich syndrome protein (WASP) gene. In this study we investigated the role of WASP in the differentiation of CD34‐positive (CD34+) cells isolated from the bone marrow of patients with WAS (n = 5) or with XLT (n = 4). Megakaryocyte colony formation was significantly decreased in patients with WAS when compared with normal controls. The formation of granulocyte‐macrophage colonies and erythroid bursts were also decreased in WAS patinets. In contrast, in XLT patients, formation of all these colonies was normal. However, in vitro proplatelet formation of megakaryocytes induced by thrombopoietin was markedly decreased in both XLT and WAS. Electron microscopic examination revealed that megakaryocytes obtained from WAS or XLT patients grown in vitro had abnormal morphologic features, which seemed to be caused by defective actin cytoskeletal organization, including labyrinth‐like structures of the demarcation membrane system and deviated distribution of the α‐granules and demarcation membrane system. These observations indicate that WASP is involved in the proliferation and differentiation of CD34+ haemopoietic progenitor cells probably by its participation in signal transduction and in the regulation of the cytoskeleton.

Mutations of the CD40 ligand gene in 13 Japanese patients with X-linked hyper-IgM syndrome

Abstract X-linked hyper-IgM syndrome (XHIM) is a rare primary immunodeficiency caused by a defective CD40 ligand. We identified mutations of the CD40 ligand gene in 13 unrelated Japanese XHIM patients. Of the four patients with missense mutations, one had a mutation within the transmembrane domain, and the three others had mutations affecting the TNF homology region of the extracellular domain. Two of the missense mutations resulted in the substitution of amino acids that are highly conserved in TNF family proteins. Three patients had nonsense mutations, all of which resulted in the truncation of the TNF homology domain of the CD40 ligand. Three patients had genomic DNA deletions of 2, 3 or 4 nucleotides, respectively. All of the deletions were flanked by direct repeat sequences, suggesting that these deletions were caused by slipped mispairing. Three patients had mutations within introns resulting in altered splicing, and multiple splicing products were found in one patient. Thus, each of the 13 Japanese patients had different mutations, 9 of them being novel mutations. These results indicate that mutations in XHIM are highly heterogeneous, although codon 140 seems to be a hot spot of the CD40 ligand gene since two additional point mutations were located at Trp 140, bringing the total numbers of mutations affecting codon 140 to six. In one XHIM family with a missense mutation, prenatal diagnosis was performed by single-strand conformation polymorphism analysis of genomic DNA of a male fetus.

Monoclonal proliferation of Epstein-Barr virus-infected T-cells in a patient with virus-associated haemophagocytic syndrome

Virus-associated haemophagocytic syndrome (VAHS) is a non-neoplastic, generalized histiocytic proliferation disorder showing marked haemophagocytosis associated with systemic viral infection. We describe the case of a 1-year-old girl with Epstein-Barr virus (EBV)-related VAHS, in whom Southern blot analysis showed monoclonal proliferation of bone marrow cells with the EBV genome; detected with the Xho-1 fragment of the latent infection membrane protein genome. EBV serology showed anti-Epstein-Barr virus nuclear associated antigen (EBNA), anti-viral capsid antigen (VCA)-IgG, anti-VCA-IgA elevation and positive EBNA of Sheep red blood cells (SRBC)-rosette-forming bone marrow cells in the late period of her clinical course, indicative of EBV infection. DNA analysis of her bone marrow cells showed monoclonal rearrangement of the T-cell receptor-β and-ψ chain genes but not of the immunoglobulin heavy chain genes. Those results suggest that EBV may infect T-cells, after which the cells proliferate monoclonally. Repeated administration of epipodophyllotoxin VP-16-213 induced remission, but adrenocortical steroid, vincristine, and cyclophosphamide had no effect on the patients condition. Ours is a first case report of VAHS showing monoclonal proliferation of EBV-infected T-cells.

Effect of recombinant interleukin 5 on the generation of cytotoxic T cells (CTL)

The effect of recombinant human interleukin 5 (rhIL5) on the generation of CTL was investigated by using autologous EBV-transformed B cells as the target. Exogenous IL5 augmented the CTL generation, and its effect was most active at the concentration of 10 ng/ml, and when added at the late phase of culture in this system. IL5 augmented specific CTL activity rather than MHC nonrestricted CTL activity as detected with K562 and Daudi when compared to that augmented by IL2. IL5 did not increase the expression of p55 or p75 IL2R nor the responsiveness to IL2. Taken together with the finding that IL5 augmented the CTL activity even in the presence of cyclosporin A, the effect of IL5 on the CTL generation seems not to act through the IL2-IL2R system.

The increase of non-MHC-restricted cytotoxic cells (γδ-TCR-bearing T cells or NK cells) and the abnormal differentiation of B cells in Wiskott-Aldrich syndrome

The objective of this study was to analyze the configuration of the lymphocytes in Wiskott-Aldrich syndrome (WAS) by studying the surface antigens from nine cases using dual-color immunofluorescence analysis. All the patients showed the increase of non-MHC-restricted cytotoxic cells, namely CD3+WT31−δTCS1+ (γδ-T cell receptor (TCR)-bearing cells) and/or CD16+ natural killer cells. The γδ-TCR+ cells of WAS, however, were unique since they did not express CD5, which is present on ordinary γδ-TCR+ cells. A reduced number of CD4+ cells and an increased percentage of CD11b+Leu7+ cells within a CD8+ subset were observed in all cases. With regard to B cell subpopulations, most cases showed reduced FcϵR2-bearing B cells, despite an elevated serum IgE.

Pattern of cytokine production by T cells from adolescents with asthma in remission after stimulation with dermatophagoides farinae antigen

ABSTRACT: Children with asthma usually become asymptomatic by the time they reach age 20 y. To clarify the immunologic mechanisms responsible for this phenomenon, we studied patients in remission and others who still had frequent asthma attacks. Patients were grouped by clinical status, and three variables were measured: serum levels of lgE, production of 11.4 and interferon (IFN)-γ, and the activation of T cells induced by Dermaophagoides farinae (DF) antigen. Df-induced activation of T cells (as measured by antigen-induced 11.2 responsiveness) or 11.2 synthesis itself was induced in patients with active asthma but not in normal subjects. These responses were much weaker in patients in remission. When stimulated by Df antigen in vitro, lymphocytes from patients with active asthma produced much more 11.4 than did the cells from normal subjects, and cells from patients in remission produced only a small amount. In contrast, under similar conditions lymphocytes from patients with active asthma produced less IFN-γ than did the cells from normal subjects. Production of IFN-γ stimulated by Df antigen was high in patients in remission but not in normal subjects. Thus, up-regulated IFN-γ production after exposure to Df antigen might reduce 11.4 secretion, which would suppress IgE production and would improve clinical status. Df antigen may suppress Df-induced allergic responses in patients with asthma in remission.