453 results match your criteria: "Research Center for Allergy and Immunology[Affiliation]"
Trends Immunol
July 2011
Research Unit for Immune Homeostasis, RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
Forkhead box P3 (Foxp3)(+) regulatory T (Treg) cells represent a distinct cell lineage that is committed to suppressive functions, whose stable differentiation state ensures the robustness of self-tolerance and immune homeostasis in a changing environment. Recent studies have challenged this notion and suggest that Treg cells retain developmental plasticity to be reprogrammed to Foxp3(-) helper T cells in response to extrinsic perturbations such as inflammation and lymphopenia. This issue of Treg cell plasticity, however, remains controversial because other recent reports argue against the plasticity phenomena.
View Article and Find Full Text PDFImmunity
June 2011
Research Unit for Immunodynamics, RIKEN, Research Center for Allergy and Immunology, Yokohama, 230-0045, Japan.
The transcription factor Bcl6 is essential for the development of germinal center (GC) B cells and follicular helper T (Tfh) cells. However, little is known about in vivo dynamics of Bcl6 protein expression during and after development of these cells. By using a Bcl6 reporter mouse strain, we found that antigen-engaged B cells upregulated Bcl6 before clustering in GCs.
View Article and Find Full Text PDFMetallomics
July 2011
Laboratory for Cytokine Signaling, RIKEN Research Center for Allergy and Immunology, Yokohama, Japan.
Zinc (Zn) is a vital element. It plays indispensable roles in multifarious cellular processes, affecting the expression and activity of a variety of molecules, including transcription factors, enzymes, adapters, channels, growth factors, and their receptors. A disturbance in Zn homeostasis due to Zn deficiency or an excess of Zn absorption can therefore impair the cellular machinery and exert various influences on physiological programs, such as systemic growth, morphogenetic processes, and immune responses, as well as neuro-sensory and endocrine functions.
View Article and Find Full Text PDFSci Signal
April 2011
Laboratory for Lymphocyte Differentiation, Research Center for Allergy and Immunology, RIKEN, Yokohama, Kanagawa 230-0045, Japan.
In immune cells, the positive role of the extracellular signal-regulated kinase (ERK) signaling pathway in cell cycle progression and survival is well established; however, it is unclear whether ERK signaling plays a role in cell differentiation. Here, we report that ERKs are essential for the differentiation of B cells into antibody-producing plasma cells and that ERKs induce the expression of Prdm1, which encodes Blimp-1, a transcriptional repressor and "master regulator" of plasma cell differentiation. Transgenic mice with conditional deletion of both ERK1 and ERK2 in germinal center (GC) B cells lacked plasma cells differentiated after GC formation, and memory B cells from these mice failed to differentiate into plasma cells.
View Article and Find Full Text PDFGut Microbes
September 2012
Laboratory for Epithelial Immunobiology, Research Center for Allergy and Immunology, RIKEN, Yokohama, Kanagawa, Japan.
Membranous (M) cells are specialized epithelial antigen-transporting cells scattered in the follicle-associated epithelium covering the gut lymphoid follicles such as Peyer's patches. Although the importance of M cells as a main portal for luminal antigens has long been recognized, molecular mechanisms for M-cell antigen uptake has remained largely elusive. We have recently found that glycoprotein 2 (GP2) is exclusively expressed on M cells among intestinal epithelial cells and serves as an uptake receptor for a subset of commensal and pathogenic bacteria.
View Article and Find Full Text PDFNat Immunol
May 2011
Laboratory for Signal Network, Research Center for Allergy and Immunology, RIKEN Yokohama Institute, Yokohama, Japan.
The immunoregulatory cytokine interleukin 10 (IL-10) is expressed mainly by T helper type 2 (T(H)2) cells but also by T(H)1 cells during chronic infection. Here we observed plasticity in the expression of IL-10 and IL-13 after chronic T(H)1 stimulation; furthermore, the expression of Il10 and Il13 was regulated by the transcription factor E4BP4. Chronically stimulated E4BP4-deficient (Nfil3(-/-); called 'E4bp4(-/-)' here) T(H)1 cells, regulatory T cells (T(reg) cells) and natural killer T cells (NKT cells) had attenuated expression of IL-10 and IL-13.
View Article and Find Full Text PDFJ Immunol
May 2011
Research Unit for Cellular Immunotherapy, Research Center for Allergy and Immunology, The Institute of Physical and Chemical Research (RIKEN), Yokohama, Kanagawa 230-0045, Japan.
Immunotherapy using dendritic cells (DCs) has the potential to activate both T cells and NK cells. We previously demonstrated the long-lasting antitumor responses by NK cells following immunization with bone marrow-derived DCs. In the current study, we demonstrate that long-term antitumor NK responses require endogenous DCs and a subset of effector memory CD4(+) T (CD4(+) T(EM)) cells.
View Article and Find Full Text PDFPLoS One
March 2011
Laboratory for Cytokine Signaling, RIKEN Research Center for Allergy and Immunology, Suehiro, Tsurumi, Yokohama, Kanagawa, Japan.
Aberrant zinc (Zn) homeostasis is associated with abnormal control of mammalian growth, although the molecular mechanisms of Zn's roles in regulating systemic growth remain to be clarified. Here we report that the cell membrane-localized Zn transporter SLC39A14 controls G-protein coupled receptor (GPCR)-mediated signaling. Mice lacking Slc39a14 (Slc39a14-KO mice) exhibit growth retardation and impaired gluconeogenesis, which are attributable to disrupted GPCR signaling in the growth plate, pituitary gland, and liver.
View Article and Find Full Text PDFInt Immunol
April 2011
Laboratory for Epithelial Immunobiology, Research Center for Allergy and Immunology, RIKEN, Yokohama, Kanagawa 230-0045, Japan.
M cells are responsible for uptake of mucosal antigens in Peyer's patches (PPs). Differentiation of M cells is thought to be induced by interactions between follicle-associated epithelium and PP cells; however, it remains elusive what types of immune cells function as M-cell inducers. Here, we attempted to identify the cells that serve as an M-cell inducer in PP.
View Article and Find Full Text PDFSeikagaku
January 2011
Laboratory for Epithelial Immunobiology, RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230 0045, Japan.
Immunol Lett
July 2011
Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama 230-0045, Japan.
BMC Syst Biol
February 2011
Laboratory for Cellular Systems Modeling, RIKEN Research Center for Allergy and Immunology (RCAI), 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.
Background: Epidermal growth factor receptor (EGFR) signaling plays an important role in the regulation of cell proliferation, survival, metastasis, and invasion in various tumors. Earlier studies showed that the EGFR is frequently overexpressed in non-small-cell lung cancer (NSCLC) and EGFR mutations at specific amino acid residues in the kinase domain induce altered responsiveness to gefitinib, a small molecule EGFR tyrosine kinase inhibitor. However, the mechanism underlying the drug response modulated by EGFR mutation is still largely unknown.
View Article and Find Full Text PDFNature
January 2011
Laboratory for Epithelial Immunobiology, RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan.
The human gut is colonized with a wide variety of microorganisms, including species, such as those belonging to the bacterial genus Bifidobacterium, that have beneficial effects on human physiology and pathology. Among the most distinctive benefits of bifidobacteria are modulation of host defence responses and protection against infectious diseases. Nevertheless, the molecular mechanisms underlying these effects have barely been elucidated.
View Article and Find Full Text PDFCell Struct Funct
August 2011
Laboratory for Immunogenomics, RIKEN Research Center for Allergy and Immunology, Yokohama 230-0045, Japan.
We investigated the effects of SP600125 (formerly called c-Jun N-terminal kinase (JNK) inhibitor II) on translation using cultured mouse cells. SP600125 (50 µM) treatment rapidly repressed overall protein synthesis, accompanied by a reduction in the mRNAs for housekeeping genes such as glyceraldehyde-3-phosphate dehydrogenase in the polysomal fraction. SP600125 decreased polysomes with a concomitant increase in free ribosomal subunits in the cytoplasm, suggesting that global translation was inhibited at the initiation step.
View Article and Find Full Text PDFInt J Hematol
February 2011
Department of Bioregulatory Medicine, Graduate School of Medicine, Ehime University, Toon, Ehime, Japan.
Peripheral T-cell lymphoma (PTCL) is a biologically diverse lymphoid malignancy. The clinical aggressiveness associated with hemophagocytic syndrome (HS) is a characteristic of PTCL, being more distinctive in CD8(+) PTCL. However, the underlying mechanism of PTCL-associated HS has not yet been fully investigated.
View Article and Find Full Text PDFYakugaku Zasshi
January 2011
Laboratory for Cytokine Signaling, RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama, Japan.
Zinc (Zn) is an essential nutrient and its deficiency causes growth retardation, immunodeficiency, and neuronal degeneration. Zn homeostasis is tightly controlled by transporting through Zn transporters and by buffering via metallothioneins, all of which are involved in the intricate regulation of Zn concentration and distribution in individual cells. Research in understanding of these molecules has progressed with application of genetic techniques, which allow us to clarify the diverse role of Zn in vivo and in vitro.
View Article and Find Full Text PDFImmunity
January 2011
Laboratory for Innate Cellular Immunity, RIKEN Research Center for Allergy and Immunology, Yokohama, Kanagawa 230-0045, Japan.
The generation of tumor-directed cytotoxic T lymphocytes is considered crucial for the induction of antitumor immunity. To activate these CD8(+) T cells, antigen-presenting cells (APCs) must initially acquire tumor cell-associated antigens. The major source of tumor antigens is dead tumor cells, but little is known about how APCs in draining lymph nodes acquire and crosspresent these antigens.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2011
Laboratory for Mucosal Immunity, RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama 230-0045, Japan.
B1 cells represent a distinct subset of B cells that produce most of the natural serum IgM and much of the gut IgA and function as an important component of early immune responses to pathogens. The development of B1 cells depends on the nuclear factor of activated T cells c1 (NFATc1), a transcription factor abundantly expressed by B1 cells but not by conventional B2 cells. However, the factors that regulate the expression of NFATc1 in B1 cells remain unknown.
View Article and Find Full Text PDFJ Immunol
February 2011
Laboratory for Transcriptional Regulation, Research Center for Allergy and Immunology, RIKEN, Yokohama 230-0045, Japan.
Hematopoietic lymphoid tissue inducer (LTi) cells are essential for the development of secondary lymphoid tissues including lymph nodes and Peyer's patches. Two transcription factors, the helix-loop-helix inhibitor Id2 and the retinoic acid-related orphan receptor γt (Rorγt), have been shown to be crucial for LTi cell development. However, it remains unclear how the specification of multipotent hematopoietic progenitor cells toward the LTi lineage is programmed.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
November 2011
Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
Strains HM2-1 and HM2-2(T) were isolated from the faeces of a healthy infant and were characterized by determining their phenotypic and biochemical features and phylogenetic positions based on partial 16S rRNA gene sequence analysis. They were Gram-positive, obligately anaerobic, non-spore-forming, non-gas-producing, and catalase-negative non-motile rods. They did not grow at 15 or 45 °C in anaerobic bacterial culture medium, and their DNA G+C content was in the range 56-59 mol%.
View Article and Find Full Text PDFNat Immunol
January 2011
Laboratory for Signal Network, Research Center for Allergy and Immunology, RIKEN Yokohama Institute, Yokohama, Japan.
GATA-3 is a master regulator of T helper type 2 (T(H)2) differentiation. However, the molecular basis of GATA-3-mediated T(H)2 lineage commitment is poorly understood. Here we identify the DNase I-hypersensitive site 2 (HS2) element located in the second intron of the interleukin 4 locus (Il4) as a critical enhancer strictly controlled by GATA-3 binding.
View Article and Find Full Text PDFFEBS Lett
December 2010
Laboratory for Cell Signaling, RIKEN Research Center for Allergy and Immunology, Tsurumi-ku, Yokohama, Japan.
TCR-microclusters (MC) are generated upon TCR stimulation prior to the immune synapse formation independently of lipid rafts. TCR-MCs contain receptors, kinases and adaptors, and function as the signaling unit for T cell activation. The TCR complex, but not the signaling molecules, is transported to the center to form cSMAC.
View Article and Find Full Text PDFMol Cell Biol
January 2011
RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro, Tsurumi-ku, Yokohama 230-0045, Japan.
The Polycomb group of proteins forms at least two distinct complexes designated the Polycomb repressive complex-1 (PRC1) and PRC2. These complexes cooperate to mediate transcriptional repression of their target genes, including the Hox gene cluster and the Cdkn2a genes. Mammalian Polycomb-like gene Pcl2/Mtf2 is expressed as four different isoforms, and the longest one contains a Tudor domain and two plant homeodomain (PHD) fingers.
View Article and Find Full Text PDFAdv Immunol
February 2011
Research Center for Allergy and Immunology, RIKEN Yokohama Tsurumi, Yokohama, Japan.
Since its discovery more than four decades ago, immunoglobulin (Ig) A has been the subject of continuous and intensive studies. The major concepts derived were that the precursors of IgA plasma cells are generated in follicular organized structures with the help of T cells and the secreted IgAs provide protection against mucosal pathogens. However, only recently we began to appreciate that IgAs play key roles in regulation of bacterial communities in the intestine and that the repertoire of gut microbiota is closely linked to the proper functioning of the immune system.
View Article and Find Full Text PDFImmunol Rev
November 2010
Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, Japan.
Most hematology and immunology textbooks describe that the first branch point from the hematopoietic stem cells (HSCs) produces two progenitors, one for myelo-erythroid cells and the other for lymphoid cells including T and B cells. This model is based on the concept that the blood cell family can be subdivided into two major lineages, a myelo-erythroid lineage and a lymphoid lineage. Several alternative models have been proposed during the last three decades.
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