2601
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Journal Club. Kidney Int 2007. [DOI: 10.1038/sj.ki.5002096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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2602
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Sigmundsdottir H, Pan J, Debes GF, Alt C, Habtezion A, Soler D, Butcher EC. DCs metabolize sunlight-induced vitamin D3 to 'program' T cell attraction to the epidermal chemokine CCL27. Nat Immunol 2007; 8:285-93. [PMID: 17259988 DOI: 10.1038/ni1433] [Citation(s) in RCA: 455] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Accepted: 12/21/2006] [Indexed: 12/20/2022]
Abstract
During adaptive immune responses, dendritic cells activate T cells and endow them with specific homing properties. Mechanisms that 'imprint' specific tropisms, however, are not well defined. We show here that 1,25(OH)(2)D(3), the active form of vitamin D3, signaled T cells to express CC chemokine receptor 10, which enabled them to migrate to the skin-specific chemokine CCL27 secreted by keratinocytes of the epidermis. In contrast, 1,25(OH)(2)D(3) suppressed the gut-homing receptors alpha4beta7 and CCR9. Vitamin D3, the inactive prohormone naturally generated in the skin by exposure to the sun, was processed by dendritic cells and T cells to the active metabolite, providing a mechanism for the local regulation of T cell 'epidermotropism'. Our findings support a model in which dendritic cells process and 'interpret' locally produced metabolites to 'program' T cell homing and microenvironmental positioning.
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Affiliation(s)
- Hekla Sigmundsdottir
- Laboratory of Immunology and Vascular Biology, Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA
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2603
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Crowley S, Gurley S, Herrera M, Ruiz P, Griffiths R, Kumar A, Kim HS, Smithies O, Le T, Coffman T. Role of Renal Angiotensin II Type 1 Receptors in the Genesis of Hypertension: Guyton Revisited. J Am Soc Nephrol 2007. [DOI: 10.1681/asn.2006121393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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2604
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Norval M, Cullen AP, de Gruijl FR, Longstreth J, Takizawa Y, Lucas RM, Noonan FP, van der Leun JC. The effects on human health from stratospheric ozone depletion and its interactions with climate change. Photochem Photobiol Sci 2007; 6:232-51. [PMID: 17344960 DOI: 10.1039/b700018a] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Ozone depletion leads to an increase in the ultraviolet-B (UV-B) component (280-315 nm) of solar ultraviolet radiation (UVR) reaching the surface of the Earth with important consequences for human health. Solar UVR has many harmful and some beneficial effects on individuals and, in this review, information mainly published since the previous report in 2003 (F. R. de Gruijl, J. Longstreth, M. Norval, A. P. Cullen, H. Slaper, M. L. Kripke, Y. Takizawa and J. C. van der Leun, Photochem. Photobiol. Sci., 2003, 2, pp. 16-28) is discussed. The eye is exposed directly to sunlight and this can result in acute or long-term damage. Studying how UV-B interacts with the surface and internal structures of the eye has led to a further understanding of the location and pathogenesis of a number of ocular diseases, including pterygium and cataract. The skin is also exposed directly to solar UVR, and the development of skin cancer is the main adverse health outcome of excessive UVR exposure. Skin cancer is the most common form of malignancy amongst fair-skinned people, and its incidence has increased markedly in recent decades. Projections consistently indicate a further doubling in the next ten years. It is recognised that genetic factors in addition to those controlling pigment variation can modulate the response of an individual to UVR. Several of the genetic factors affecting susceptibility to the development of squamous cell carcinoma, basal cell carcinoma and melanoma have been identified. Exposure to solar UVR down-regulates immune responses, in the skin and systemically, by a combination of mechanisms including the generation of particularly potent subsets of T regulatory cells. Such immunosuppression is known to be a crucial factor in the generation of skin cancers. Apart from a detrimental effect on infections caused by some members of the herpesvirus and papillomavirus families, the impact of UV-induced immunosuppression on other microbial diseases and vaccination efficacy is not clear. One important beneficial effect of solar UV-B is its contribution to the cutaneous synthesis of vitamin D, recognised to be a crucial hormone for bone health and for other aspects of general health. There is accumulating evidence that UVR exposure, either directly or via stimulation of vitamin D production, has protective effects on the development of some autoimmune diseases, including multiple sclerosis and type 1 diabetes. Adequate vitamin D may also be protective for the development of several internal cancers and infections. Difficulties associated with balancing the positive effects of vitamin D with the negative effects of too much exposure to solar UV-B are considered. Various strategies that can be adopted by the individual to protect against excessive exposure of the eye or the skin to sunlight are suggested. Finally, possible interactions between ozone depletion and climate warming are outlined briefly, as well as how these might influence human behaviour with regard to sun exposure.
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Affiliation(s)
- M Norval
- Medical Microbiology, University of Edinburgh Medical School, Teviot Place, Edinburgh, EH8 9AG, Scotland
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2605
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Appelberg R. Pathogenesis of Mycobacterium avium infection: typical responses to an atypical mycobacterium? Immunol Res 2007; 35:179-90. [PMID: 17172645 DOI: 10.1385/ir:35:3:179] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 01/02/2023]
Abstract
Studying infections with Mycobacterium avium in mouse models has allowed the dissection of the antimycobacterial pathways of the mammalian host. Whereas the paradigm of cell-mediated immunity to intracellular pathogens has been confirmed, namely with regard to the pivotal roles of CD4+ T cells, macrophages, and the IL12-IFNgamma cytokine axis, atypical features have been uncovered such as the resistance to NO, the involvement of minor players in the induction of type 1 protective immunity (such as TLR2, CD40, and CD30), and the development of immunopathology during the infection with highly virulent strains such as the development of caseous necrosis of granulomas or the progressive emergence of severe lymphopenia.
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Affiliation(s)
- Rui Appelberg
- Laboratory of Microbiology and Immunology of Infection, IBMC-Institute for Molecular and Cell Biology and ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, Portugal.
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2606
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2607
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Wittke A, Chang A, Froicu M, Harandi OF, Weaver V, August A, Paulson RF, Cantorna MT. Vitamin D receptor expression by the lung micro-environment is required for maximal induction of lung inflammation. Arch Biochem Biophys 2007; 460:306-13. [PMID: 17224129 PMCID: PMC1933487 DOI: 10.1016/j.abb.2006.12.011] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 12/04/2006] [Accepted: 12/06/2006] [Indexed: 01/09/2023]
Abstract
Mice lacking the vitamin D receptor (VDR) are resistant to airway inflammation. Pathogenic immune cells capable of transferring experimental airway inflammation to wildtype (WT) mice are present and primed in the VDR KO mice. Furthermore, the VDR KO immune cells homed to the WT lung in sufficient numbers to induce symptoms of asthma. Conversely, WT splenocytes, Th2 cells and hematopoetic cells induced some symptoms of experimental asthma when transferred to VDR KO mice, but the severity was less than that seen in the WT controls. Interestingly, experimentally induced vitamin D deficiency failed to mirror the VDR KO phenotype suggesting there might be a difference between absence of the ligand and VDR deficiency. Lipopolysaccharide (LPS) induced inflammation in the lungs of VDR KO mice was also less than in WT mice. Together the data suggest that vitamin D and the VDR are important regulators of inflammation in the lung and that in the absence of the VDR the lung environment, independent of immune cells, is less responsive to environmental challenges.
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Affiliation(s)
- Anja Wittke
- Center for Immunology and Infectious Disease, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Andrew Chang
- Integrated Biosciences Graduate Program, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Monica Froicu
- Pathobiology Graduate Program, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Omid F. Harandi
- Genetics Graduate Program, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Veronika Weaver
- Center for Immunology and Infectious Disease, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Avery August
- Center for Immunology and Infectious Disease, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Robert F. Paulson
- Center for Immunology and Infectious Disease, Department of Veterinary and Biomedical Science, The Pennsylvania State University, University Park, PA 16802
| | - Margherita T. Cantorna
- Address correspondence to Dr. Margherita T. Cantorna, Department of Veterinary and Biomedical Sciences, The Center for Molecular Immunology and Infectious Disease, 115, Henning Bldg., University Park, PA, 16802, Phone: 814–863–2819, Fax: 814–863–6140, E-mail address:
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2608
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Abstract
In the absence of significant, unpreventable risks, breastfeeding should be the norm for the nourishment of human infants and should, therefore, be encouraged for populations in all countries. Continued efforts of international and national agencies and healthcare professionals to aid and abet breastfeeding, reduce the risks that occur in some women during breastfeeding, provide the safest substitutes for human milk when that is necessary, and encourage further research into the posed questions should considerably improve the health of many children.
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Affiliation(s)
- Armond S Goldman
- Department of Pediatrics, The University of Texas Medical Branch, Galveston, TX 77555-0369, USA.
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2609
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Szeszko JS, Healy B, Stevens H, Balabanova Y, Drobniewski F, Todd JA, Nejentsev S. Resequencing and association analysis of the SP110 gene in adult pulmonary tuberculosis. Hum Genet 2006; 121:155-60. [PMID: 17149599 DOI: 10.1007/s00439-006-0293-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2006] [Accepted: 10/30/2006] [Indexed: 11/28/2022]
Abstract
Recently, the Intracellular pathogen resistance 1 (Ipr1) gene was shown to control susceptibility to Mycobacterium tuberculosis in mice. We examined whether common sequence variants of its human orthologue, the SP110 gene, are associated with susceptibility to tuberculosis in a human population. We resequenced SP110 exons in 96 individuals and identified new polymorphisms. Then, we combined our sequence and HapMap data for 83 distinct polymorphisms and selected tags that capture information for all common variants in the 100 kb region around SP110. We genotyped 29 single nucleotide polymorphisms including seven amino-acid changing variants in 1,912 HIV-negative culture-confirmed adult pulmonary tuberculosis patients and 2,104 adult healthy controls from Russia and found no evidence of association. Our results indicate that common polymorphisms of the SP110 gene have no major effect on susceptibility to tuberculosis in this population.
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Affiliation(s)
- Jeffrey S Szeszko
- Juvenile Diabetes Research Foundation/Wellcome Trust Diabetes and Inflammation Laboratory, Cambridge Institute for Medical Research, Department of Medical Genetics, University of Cambridge, WT/MRC building, Addenbrooke's Hospital, Cambridge, CB2 2XY, UK
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2610
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Bouillon R, Verstuyf A, Mathieu C, Van Cromphaut S, Masuyama R, Dehaes P, Carmeliet G. Vitamin D resistance. Best Pract Res Clin Endocrinol Metab 2006; 20:627-45. [PMID: 17161336 DOI: 10.1016/j.beem.2006.09.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vitamin D is a secosteroid of nutritional origin but can also be generated in the skin by ultraviolet light. After two hydroxylations 1,25-(OH)2 vitamin D avidly binds and activates the vitamin D receptor (VDR), a nuclear transcription factor, hereby regulating a large number of genes. The generation of VDR deficient mice has expanded the knowledge on vitamin D from a calcium-regulating hormone to a humoral factor with extensive actions. The effects of the vitamin D system on calcium and bone homeostasis are largely mediated by promoting active intestinal calcium transport via the induction of the epithelial calcium channel TRPV6. Although VDR is redundant in bone, it may regulate the differentiation and function of several bone cells. In skin, VDR expression in keratinocytes is essential in a ligand-independent manner for the maintenance of the normal hair cycle. Therefore, VDR but not vitamin D deficiency results in alopecia. Moreover, 1,25-(OH)2 vitamin D impairs the proliferation not only of keratinocytes but also of many cell types by regulating the expression of cell cycle genes, leading to a G1 cell cycle arrest. In addition, VDR inactivation in mice results in high renin hypertension, cardiac hypertrophy and thrombogenesis. Finally, a dual effect of vitamin D was observed in the immune system where it stimulates the innate immune system while tapering down excessive activation of the acquired immune system. Taken together, the vitamin D endocrine system not only regulates calcium homeostasis but affects several systems mainly by altering gene expression but also by ligand-independent actions.
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Affiliation(s)
- Roger Bouillon
- Laboratory for Experimental Medicine and Endocrinology, Campus Gasthuisberg, Onderwijs & Navorsing 1, Herestraat 49, bus 902, B-3000 Leuven, Belgium.
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2611
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Cannell JJ, Vieth R, Umhau JC, Holick MF, Grant WB, Madronich S, Garland CF, Giovannucci E. Epidemic influenza and vitamin D. Epidemiol Infect 2006; 134:1129-40. [PMID: 16959053 PMCID: PMC2870528 DOI: 10.1017/s0950268806007175] [Citation(s) in RCA: 674] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2006] [Indexed: 12/28/2022] Open
Abstract
In 1981, R. Edgar Hope-Simpson proposed that a 'seasonal stimulus' intimately associated with solar radiation explained the remarkable seasonality of epidemic influenza. Solar radiation triggers robust seasonal vitamin D production in the skin; vitamin D deficiency is common in the winter, and activated vitamin D, 1,25(OH)2D, a steroid hormone, has profound effects on human immunity. 1,25(OH)2D acts as an immune system modulator, preventing excessive expression of inflammatory cytokines and increasing the 'oxidative burst' potential of macrophages. Perhaps most importantly, it dramatically stimulates the expression of potent anti-microbial peptides, which exist in neutrophils, monocytes, natural killer cells, and in epithelial cells lining the respiratory tract where they play a major role in protecting the lung from infection. Volunteers inoculated with live attenuated influenza virus are more likely to develop fever and serological evidence of an immune response in the winter. Vitamin D deficiency predisposes children to respiratory infections. Ultraviolet radiation (either from artificial sources or from sunlight) reduces the incidence of viral respiratory infections, as does cod liver oil (which contains vitamin D). An interventional study showed that vitamin D reduces the incidence of respiratory infections in children. We conclude that vitamin D, or lack of it, may be Hope-Simpson's 'seasonal stimulus'.
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Affiliation(s)
- J J Cannell
- Atascadero State Hospital, 10333 El Camino Real, Atascadero, CA 93422, USA.
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2612
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Abstract
The vitamin D receptor (VDR) is a member of the large family of nuclear receptor transcription factors and specifically binds the micronutrient-derived hormone 1alpha,25(OH)2D3. A central endocrine role for this receptor in bone health was established at the beginning of the 20th century. Over the last 25 years, additional roles, perhaps through autocrine and paracrine mechanisms, have been established for VDR to regulate cell proliferation and differentiation, and more recently to exert immunomodulatory and antimicrobial functions. These findings, from in vitro and in vivo experiments, have generated considerable interest in targeting the VDR in multiple therapeutic settings. As with many potential therapeutics, it has also become clear that cells and tissues may also display de novo and acquired mechanisms of resistance to these actions. Consequently, a range of experimental and clinical options are being developed to bring about more targeted actions, overcome resistance and enhance efficacy of VDR-centred therapeutics.
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Affiliation(s)
- Moray J Campbell
- Institute of Biomedical Research, Wolfson Drive, University of Birmingham Medical School, Edgbaston, Birmingham, B15 2TT, UK.
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2613
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2614
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Abstract
Mammalian innate immunity stimulates antigen-specific immune responses and acts to control infection prior to the onset of adaptive immunity. Some bacterial pathogens replicate within the host cell and are therefore sheltered from some protective aspects of innate immunity such as complement. Here we focus on mechanisms of innate intracellular resistance encountered by bacterial pathogens and how some bacteria can evade destruction by the innate immune system. Major strategies of intracellular antibacterial defence include pathogen compartmentalization and iron limitation. Compartmentalization of pathogens within the host endocytic pathway is critical for generating high local concentrations of antimicrobial molecules, such as reactive oxygen species, and regulating concentrations of divalent cations that are essential for microbial growth. Cytosolic sensing, autophagy, sequestration of essential nutrients and membrane attack by antimicrobial peptides are also discussed.
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Affiliation(s)
- Andrea L Radtke
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-0620, USA
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2615
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Abstract
Oral vitamin D supplementation has been introduced into modern medicine to prevent rickets without the knowledge that this may have profound immunological consequences. The main vitamin D metabolite calcitriol suppresses dendritic cell maturation and consecutive Th(1) cell development, which has independently described as a key mechanism of allergy development. Animal studies and epidemiological surveys now provide a first link of early vitamin D supplementation and later allergy where several vitamin D regulated genes seem to be involved. A randomized clinical trial of vitamin D supplementation could be a further step to follow up the vitamin hypothesis.
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2616
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Liu P, Stenger S, Li H, Wenzel L, Tan B, Krutzik S, Ochoa M, Schauber J, Wu K, Meinken C, Kamen D, Wagner M, Bals R, Steinmeyer A, Zugel U, Gallo R, Eisenberg D, Hewison M, Hollis B, Adams J, Bloom B, Modlin R. Vitamin D3–Triggered Antimicrobial Response—Another Pleiotropic Effect beyond Mineral and Bone Metabolism. J Am Soc Nephrol 2006. [DOI: 10.1681/asn.2006091030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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2617
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Enioutina EY, Bareyan D, Daynes RA. Vitamin D3-mediated alterations to myeloid dendritic cell trafficking in vivo expand the scope of their antigen presenting properties. Vaccine 2006; 25:1236-49. [PMID: 17092617 DOI: 10.1016/j.vaccine.2006.10.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 09/22/2006] [Accepted: 10/05/2006] [Indexed: 01/23/2023]
Abstract
The mucosal immune system provides the host with a first line of adaptive immune defense against invasion by many species of pathogenic microorganisms and their secreted products. Calcitriol, the active form of Vitamin D3 (VD3), promotes the induction of mucosal immunity in mice when added to subcutaneously administered vaccine formulations. Dendritic cells (DCs) activated at vaccination sites where VD3 is present gain the capacity to bypass sequestration in the draining lymph node and traffic to the Peyer's Patches (PP) of immunized animals. By employing protocols that allow the effective tracking of endogenous or adoptively transferred myeloid DCs in vivo, we found that VD3 influences on the trafficking of fully differentiated immature DCs were temporary, and occur without negative effects to antigen processing or peptide presentation to CD4+ T cells. In contrast, DCs differentiated from hematopoietic precursors in the presence of VD3 (conditioned DCs), were markedly compromised in their antigen presenting properties, while manifesting clear alterations to their trafficking properties in vivo. Similar to the recent finding of VD3-mediated enhancement of innate immune protection, our findings suggest that VD3 could also play an important role in controlling the types of immune effector responses elicited subsequent to either infection or vaccination.
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MESH Headings
- Adjuvants, Immunologic
- Animals
- Antigen Presentation/drug effects
- Antigen Presentation/immunology
- Bone Marrow Cells/immunology
- CD4-Positive T-Lymphocytes/immunology
- Chemotaxis, Leukocyte/immunology
- Cholecalciferol/pharmacology
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Female
- Immunity, Mucosal/immunology
- Immunotherapy, Adoptive
- Lymphoid Tissue/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C3H
- Mice, Transgenic
- Myeloid Cells/drug effects
- Myeloid Cells/immunology
- Receptors, CCR7
- Receptors, Chemokine/biosynthesis
- Receptors, Chemokine/genetics
- Skin/cytology
- Skin/immunology
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Affiliation(s)
- Elena Y Enioutina
- Department of Pathology, University of Utah Medical School, 30 North 1900 East, Salt Lake City, UT 84132, USA.
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2618
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Peyrin-Biroulet L, Vignal C, Dessein R, Simonet M, Desreumaux P, Chamaillard M. NODs in defence: from vulnerable antimicrobial peptides to chronic inflammation. Trends Microbiol 2006; 14:432-8. [PMID: 16942880 DOI: 10.1016/j.tim.2006.08.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Revised: 07/28/2006] [Accepted: 08/15/2006] [Indexed: 12/24/2022]
Abstract
Defensins and cathelicidins are prevalent and essential gastrointestinal cationic antimicrobial peptides (CAPs). However, these defensive peptides are not infallible because certain enteropathogens can overcome their protective function. Furthermore, impaired defensin synthesis has been linked to the occurrence of Crohn's disease (CD), a chronic inflammatory bowel disease. Recently, defective bacterial sensing through NOD1 and NOD2 has been related to reduced defensin production, CD predisposition and susceptibility to enteric infection. Hence, we propose that microbial sensors at the gut interface monitor the levels of these effector peptides, which might function as "danger" signals to confer tolerance and alert immunocytes. Further work is required to clarify how gastrointestinal CAPs are regulated and to assess their role in maintaining epithelial homeostasis and triggering adaptive immunity.
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Affiliation(s)
- Laurent Peyrin-Biroulet
- INSERM U795, University of Lille 2, Huriez Hospital, Digestive Tract Diseases and Nutrition Department, F-59037 Lille, France
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2619
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Vantieghem K, De Haes P, Bouillon R, Segaert S. Dermal fibroblasts pretreated with a sterol Δ7-reductase inhibitor produce 25-hydroxyvitamin D3 upon UVB irradiation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 85:72-8. [PMID: 16824767 DOI: 10.1016/j.jphotobiol.2006.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 11/29/2022]
Abstract
As dermis is a physiological site of vitamin D3 photoproduction, the photo-endocrine vitamin D3 system was studied in dermal fibroblasts. Dermal fibroblasts contain the vitamin D receptor and induce 1alpha,25-dihydroxyvitamin D3-24-hydroxylase [CYP24] mRNA upon stimulation with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. In addition, dermal fibroblasts contain mRNA of the vitamin D3-25-hydroxylases (CYP2R1 and CYP27A1). However, we could not detect any 25-hydroxyvitamin D3 [25OHD3]-1alpha-hydroxylase mRNA in dermal fibroblasts and no CYP24 mRNA was induced upon ultraviolet [UVB] irradiation, even when endogenous 7-dehydrocholesterol content was elevated by pretreatment with the sterol Delta7-reductase inhibitor BM15766. Nevertheless, dermal fibroblasts produce inactive vitamin D3 metabolites that can be activated by epidermal keratinocytes as CYP24 mRNA is induced in epidermal keratinocytes but not in dermal fibroblasts after transfer of medium or cellular suspensions from BM15766-pretreated, UVB-irradiated fibroblasts. This CYP24 induction was UVB-dose dependent and was inhibited by ketoconazole. As revealed in a competitive binding assay, BM15766-pretreated dermal fibroblasts are able to produce 25OHD3 upon UVB irradiation, but no 1,25(OH)2D3 was detected via combined high-performance liquid chromatography radioimmunoassay. The physiological relevance of dermal vitamin D3 photoproduction and its subsequent conversion into 25OHD3 remains elusive.
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Affiliation(s)
- Katleen Vantieghem
- Laboratorium voor Experimentele Geneeskunde en Endocrinologie (LEGENDO), Gasthuisberg, Katholieke Universiteit Leuven, Herestraat 49, 3000 Leuven, Belgium
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2620
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Abstract
Efforts to explore a mycobacterial origin for Crohn's disease typically have involved an epidemiological approach, searching for Mycobacterium avium subsp. paratuberculosis in patient tissue. An alternative approach involves consideration of genetic and experimental data regarding host resistance to mycobacteria. From human and mycobacterial genetics, it is known that mycobacterial diseases depend on both pathogen and host factors and that tuberculosis and leprosy are effectively genetic diseases. The discovery of a number of Crohn's susceptibility genes, including NOD2/CARD15, demonstrates that Crohn's also is a complex genetic disease. Mutations in NOD2/CARD15 do not necessarily lead to Crohn's disease, so other mitigating factors, genetic and/or environmental, probably are required to produce illness. Recent work has shown that NOD2/CARD15 serves a role in bacterial sensing and activation of innate immune responses, providing a link between Crohn's genetics and an environmental factor, potentially a bacterial trigger. In this review, we discuss the current understanding of mycobacterial and Crohn's genetic susceptibility and review the evidence that NOD2/CARD15 may mediate host resistance to mycobacterial infection.
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Affiliation(s)
- Marcel A Behr
- Department of Medicine, McGill University Faculty of Medicine, Montreal, Quebec, Canada.
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2621
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Evans KN, Nguyen L, Chan J, Innes BA, Bulmer JN, Kilby MD, Hewison M. Effects of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 on cytokine production by human decidual cells. Biol Reprod 2006; 75:816-22. [PMID: 16957024 DOI: 10.1095/biolreprod.106.054056] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The active form of vitamin D, 1,25-dihydroxyvitamin D(3) (1,25[OH](2)D(3)) is a potent immunomodulatory seco-steroid. We have demonstrated that several components of vitamin D metabolism and signaling are strongly expressed in human uterine decidua from first trimester pregnancies, suggesting that locally produced 1,25(OH)(2)D(3) may exert immunosuppressive effects during early stages of gestation. To investigate this further, we used primary cultures of human decidual cells from first and third trimester pregnancies to demonstrate expression and activity of the enzyme that catalyzes synthesis of 1,25(OH)(2)D(3), 1alpha-hydroxylase (CYP27B1). Synthesis of 1,25(OH)(2)D(3) was higher in first trimester decidual cells (41 +/- 11.8 fmoles/h/mg protein) than in third trimester cells (8 +/- 4.4 fmoles/h/mg protein; P < 0.05). Purification of decidual cells followed by quantitative RT-PCR analysis showed that CYP27B1 was expressed by both CD10(+VE) stromal-enriched and CD10(-VE) stromal-depleted cells, with higher levels of mRNA in first trimester pregnancies. Expression of CYP27B1 correlated with TLR4 and IDO. Functional responses to 1,25(OH)(2)D(3) were studied using CD56(+VE) natural killer (NK) cells isolated from first trimester decidua. Decidual NK cells treated with 1,25(OH)(2)D(3) or precursor 25-hydroxyvitamin D(3) (25OHD(3)) for 28 h showed decreased synthesis of cytokines, such as granulocyte-macrophage colony stimulating factor 2 (CSF2), tumor necrosis factor, and interleukin 6, but increased expression of mRNA for the antimicrobial peptide cathelicidin antimicrobial peptide. These data indicate that human decidual cells are able to synthesize active 1,25(OH)(2)D(3), particularly in early gestation, and this may act in an autocrine/paracrine fashion to regulate both acquired and innate immune responses at the fetal-maternal interface.
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Affiliation(s)
- Katie N Evans
- Division of Medical Sciences, Institute of Biomedical Research, The University of Birmingham, Birmingham, B15 2TT, United Kingdom
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2622
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Karakelides H, Geller JL, Schroeter AL, Chen H, Behn PS, Adams JS, Hewison M, Wermers RA. Vitamin D-mediated hypercalcemia in slack skin disease: evidence for involvement of extrarenal 25-hydroxyvitamin D 1alpha-hydroxylase. J Bone Miner Res 2006; 21:1496-9. [PMID: 16939409 DOI: 10.1359/jbmr.060608] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
UNLABELLED A case of granulomatous slack skin disease is presented in which we studied the possible involvement of extrarenal 1,25(OH)2D in the pathogenesis of the patient's hypercalcemia. Immunolocalization of 1alpha-OH in skin showed simultaneous dysregulation in epithelial and granulomatous cells. INTRODUCTION Granuloma-forming diseases such as sarcoidosis are associated with extrarenal synthesis of active 1,25-dihydroxyvitamin D [1,25(OH)2D]. Here we describe a case of granulomatous slack skin disease in which we have studied the possible involvement of extrarenal synthesis of 1,25(OH)2D in the pathogenesis of the patient's hypercalcemia. The aim of the study was to clarify the etiology of hypercalcemia in this patient. MATERIALS AND METHODS This was a case study of a 19-year-old man with a T-cell lymphoproliferative disorder diagnosed as granulomatous slack skin disease who presented with hypercalcemia and raised serum 1,25(OH)2D. Analysis of expression of the enzyme 25-hydroxyvitamin D 1alpha-hydroxylase (1alpha-hydroxylase), which catalyzes synthesis of 1,25(OH)2D, was carried out by immunohistochemical analysis of involved and uninvolved skin. Approval was granted by the Mayo Foundation Institutional Review Board and Biospecimens Subcommittee. RESULTS In uninvolved skin, expression of 1alpha-hydroxylase was confined to the basal layer of the epidermis, whereas slack skin showed overexpression of the enzyme in dermal granulomata and basal cells of the epidermis. CONCLUSIONS Hypercalcemia associated with granulomatous slack skin syndrome seems to be caused by dysregulation of 1alpha-hydroxylase expression in both epidermal and dermal granulomatous cells. This contrasts with psoriasis and sarcoidosis of the skin, in which overexpression of the enzyme is restricted to keratinocytes and granulomata, respectively.
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Affiliation(s)
- Helen Karakelides
- Department of Endocrinology, Metabolism and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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2623
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2624
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Hollis BW, Wagner CL. Vitamin D deficiency during pregnancy: an ongoing epidemic. Am J Clin Nutr 2006. [DOI: 10.1093/ajcn/84.2.273] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Bruce W Hollis
- From the Department of Pediatrics, Darby Children’s Research Institute, Medical University of South Carolina, Charleston, SC
| | - Carol L Wagner
- From the Department of Pediatrics, Darby Children’s Research Institute, Medical University of South Carolina, Charleston, SC
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2625
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Abstract
The epidemic scourge of rickets in the 19th century was caused by vitamin D deficiency due to inadequate sun exposure and resulted in growth retardation, muscle weakness, skeletal deformities, hypocalcemia, tetany, and seizures. The encouragement of sensible sun exposure and the fortification of milk with vitamin D resulted in almost complete eradication of the disease. Vitamin D (where D represents D2 or D3) is biologically inert and metabolized in the liver to 25-hydroxyvitamin D [25(OH)D], the major circulating form of vitamin D that is used to determine vitamin D status. 25(OH)D is activated in the kidneys to 1,25-dihydroxyvitamin D [1,25(OH)2D], which regulates calcium, phosphorus, and bone metabolism. Vitamin D deficiency has again become an epidemic in children, and rickets has become a global health issue. In addition to vitamin D deficiency, calcium deficiency and acquired and inherited disorders of vitamin D, calcium, and phosphorus metabolism cause rickets. This review summarizes the role of vitamin D in the prevention of rickets and its importance in the overall health and welfare of infants and children.
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Affiliation(s)
- Michael F Holick
- Department of Medicine, Section of Endocrinology, Nutrition, and Diabetes, and Vitamin D, Skin and Bone Research Laboratory, Boston University Medical Center, Boston, Massachusetts 02118, USA.
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2626
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Li M, Hener P, Zhang Z, Kato S, Metzger D, Chambon P. Topical vitamin D3 and low-calcemic analogs induce thymic stromal lymphopoietin in mouse keratinocytes and trigger an atopic dermatitis. Proc Natl Acad Sci U S A 2006; 103:11736-41. [PMID: 16880407 PMCID: PMC1544239 DOI: 10.1073/pnas.0604575103] [Citation(s) in RCA: 388] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We have demonstrated that cytokine thymic stromal lymphopoietin (TSLP), whose expression is rapidly induced upon keratinocyte-selective ablation of retinoid X receptors (RXRs) -alpha and -beta in the mouse (RXRalphabeta(ep-/-) mice), plays a key role in initiating a skin and systemic atopic dermatitis-like phenotype. We show here that topical application of the physiologically active ligand [1alpha,25-(OH)(2)D(3); calcitriol] of the vitamin D receptor, or of its low-calcemic analog MC903 (calcipotriol; Dovonex), induces TSLP expression in epidermal keratinocytes, which results in an atopic dermatitis-like syndrome mimicking that seen in RXRalphabeta(ep-/-) mutants and transgenic mice overexpressing TSLP in keratinocytes. Furthermore, topical application of retinoic acid receptor RARgamma-selective agonist BMS961 also induces TSLP expression either on its own or synergistically with 1alpha,25-(OH)(2)D(3). Our data demonstrate that RXR/vitamin D receptor and RXR/retinoic acid receptor-gamma heterodimers and their ligands cell-autonomously control the expression of TSLP in epidermal keratinocytes of the mouse. We propose molecular mechanisms through which vitamin D3 and retinoic acid signalings could be involved in the pathogenesis of atopic diseases.
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MESH Headings
- Administration, Topical
- Animals
- Calcitriol/administration & dosage
- Calcitriol/adverse effects
- Calcitriol/analogs & derivatives
- Calcitriol/immunology
- Calcium/metabolism
- Cells, Cultured
- Cytokines/genetics
- Cytokines/immunology
- Dermatitis, Atopic/chemically induced
- Dermatitis, Atopic/immunology
- Dermatologic Agents/administration & dosage
- Dermatologic Agents/adverse effects
- Dermatologic Agents/immunology
- Dimerization
- Female
- Humans
- Keratinocytes/cytology
- Keratinocytes/immunology
- Mice
- Mice, Knockout
- Mice, Transgenic
- Receptors, Calcitriol/genetics
- Receptors, Calcitriol/metabolism
- Receptors, Retinoic Acid/agonists
- Receptors, Retinoic Acid/genetics
- Receptors, Retinoic Acid/metabolism
- Retinoid X Receptor alpha/agonists
- Retinoid X Receptor alpha/genetics
- Retinoid X Receptor alpha/metabolism
- Retinoid X Receptor beta/agonists
- Retinoid X Receptor beta/genetics
- Retinoid X Receptor beta/metabolism
- Retinoids/immunology
- Skin/cytology
- Skin/drug effects
- Skin/pathology
- Vitamins/administration & dosage
- Vitamins/adverse effects
- Vitamins/chemistry
- Vitamins/immunology
- Thymic Stromal Lymphopoietin
- Retinoic Acid Receptor gamma
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Affiliation(s)
- Mei Li
- *Institut de Génétique et de Biologie Moléculaire et Cellulaire and Institut Clinique de la Souris, BP10142, 67404 Illkirch Cedex, France; and
| | - Pierre Hener
- *Institut de Génétique et de Biologie Moléculaire et Cellulaire and Institut Clinique de la Souris, BP10142, 67404 Illkirch Cedex, France; and
| | - Zhikun Zhang
- *Institut de Génétique et de Biologie Moléculaire et Cellulaire and Institut Clinique de la Souris, BP10142, 67404 Illkirch Cedex, France; and
| | - Shigeaki Kato
- Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Daniel Metzger
- *Institut de Génétique et de Biologie Moléculaire et Cellulaire and Institut Clinique de la Souris, BP10142, 67404 Illkirch Cedex, France; and
| | - Pierre Chambon
- *Institut de Génétique et de Biologie Moléculaire et Cellulaire and Institut Clinique de la Souris, BP10142, 67404 Illkirch Cedex, France; and
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2627
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Tan BH, Meinken C, Bastian M, Bruns H, Legaspi A, Ochoa MT, Krutzik SR, Bloom BR, Ganz T, Modlin RL, Stenger S. Macrophages Acquire Neutrophil Granules for Antimicrobial Activity against Intracellular Pathogens. THE JOURNAL OF IMMUNOLOGY 2006; 177:1864-71. [PMID: 16849498 DOI: 10.4049/jimmunol.177.3.1864] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A key target of many intracellular pathogens is the macrophage. Although macrophages can generate antimicrobial activity, neutrophils have been shown to have a key role in host defense, presumably by their preformed granules containing antimicrobial agents. Yet the mechanism by which neutrophils can mediate antimicrobial activity against intracellular pathogens such as Mycobacterium tuberculosis has been a long-standing enigma. We demonstrate that apoptotic neutrophils and purified granules inhibit the growth of extracellular mycobacteria. Phagocytosis of apoptotic neutrophils by macrophages results in decreased viability of intracellular M. tuberculosis. Concomitant with uptake of apoptotic neutrophils, granule contents traffic to early endosomes, and colocalize with mycobacteria. Uptake of purified granules alone decreased growth of intracellular mycobacteria. Therefore, the transfer of antimicrobial peptides from neutrophils to macrophages provides a cooperative defense strategy between innate immune cells against intracellular pathogens and may complement other pathways that involve delivery of antimicrobial peptides to macrophages.
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Affiliation(s)
- Belinda H Tan
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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2628
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Editors' Picks. J Invest Dermatol 2006. [DOI: 10.1038/sj.jid.5700358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2629
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Lombard Z, Dalton DL, Venter PA, Williams RC, Bornman L. Association of HLA-DR, -DQ, and vitamin D receptor alleles and haplotypes with tuberculosis in the Venda of South Africa. Hum Immunol 2006; 67:643-54. [PMID: 16916662 DOI: 10.1016/j.humimm.2006.04.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2005] [Indexed: 11/16/2022]
Abstract
The vitamin D receptor (VDR) and the human leukocyte antigen (HLA) class II complex affect innate and/or adaptive immunity against Mycobacterium tuberculosis. HLA-DRB1, HLA-DQB1, and VDR gene (VDR) polymorphisms were previously associated with tuberculosis (TB) and are here investigated as candidates for TB susceptibility in the Venda population of South Africa. Genomic DNA from 95 patients with pulmonary tuberculosis (PTB) and 117 ethnically matched, healthy controls were typed for HLA-DRB1, DRB3, DRB4, DRB5, DQB1, and VDR polymorphisms FokI, BsmI, ApaI, and TaqI using polymerase chain reaction-sequence specific primers (PCR-SSP). Allele and haplotype frequencies were calculated by the estimator maximum (EM) algorithm. DRB1*1302 phenotype was significantly associated with TB occurring at a significantly higher allele frequency in cases than controls and found in haplotype with DQB1*0602/3. DQB1*0301-0304 phenotype was significantly associated with TB and found in haplotype with DRB1*1101-1121, showing significant linkage disequilibrium (LD) in both cases and controls. Only DRB1*1101-1121-DQB1*05 was significantly associated with TB based on the sequential Bonferroni p value. VDR SNP phenotypes were not associated with TB, but the haplotype F-b-A-T significantly protected from TB. In conclusion, common African HLA-DRB1 and -DQB1 variants, previously associated with protection from malaria and hepatitis B/C virus persistence, predispose the Venda to TB, whereas the proposedly active VDR haplotype F-b-A-T showed significant protection.
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Affiliation(s)
- Zane Lombard
- Department of Biochemistry, University of Johannesburg, Auckland Park, South Africa
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2630
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Liu M, Popper SJ, Rubins KH, Relman DA. Early days: genomics and human responses to infection. Curr Opin Microbiol 2006; 9:312-9. [PMID: 16679048 PMCID: PMC7108404 DOI: 10.1016/j.mib.2006.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Accepted: 04/24/2006] [Indexed: 10/26/2022]
Abstract
DNA microarray-based gene transcript-profiling of the responses of primates to infection has begun to yield new insights into host-pathogen interactions; this approach, however, remains plagued by challenges and complexities that have yet to be adequately addressed. The rapidly changing nature over time of acute infectious diseases in a host, and the genetic diversity of microbial pathogens present unique problems for the design and interpretation of functional-genomic studies in this field. In addition, there are the more common problems related to heterogeneity within clinical samples, the complex, non-standardized confounding variables associated with human subjects and the complexities posed by the analysis and validation of highly parallel data. Whereas various approaches have been developed to address each of these issues, there are significant limitations that remain to be overcome. The resolution of these problems should lead to a better understanding of the dialogue between the host and pathogen.
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Affiliation(s)
- Minghsun Liu
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Grant S-169, Stanford, CA 94305, USA
| | - Stephen J Popper
- Department of Microbiology and Immunology, Stanford University School of Medicine, 279 Campus Drive, Beckman B403, Stanford, CA 94305, USA
| | - Kathleen H Rubins
- Department of Microbiology and Immunology, Stanford University School of Medicine, 279 Campus Drive, Beckman B403, Stanford, CA 94305, USA
| | - David A Relman
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Grant S-169, Stanford, CA 94305, USA
- Department of Microbiology and Immunology, Stanford University School of Medicine, 279 Campus Drive, Beckman B403, Stanford, CA 94305, USA
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, USA
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2631
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Affiliation(s)
- Bruce W Hollis
- Pediatric Nutritional Sciences, Darby Children's Research Institute, Medical University of South Carolina, Charleston, SC 29425, USA.
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2632
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2633
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Abstract
BACKGROUND Despite the higher prevalence of vitamin D deficiency in blacks, the vitamin D status of black preterm infants remains unknown. In addition, with the combination of parenteral and enteral nutritional support that preterm infants receive, the effect of vitamin D-deficient breast milk on vitamin D status is unknown. OBJECTIVE To evaluate vitamin D status of preterm infants through the first month after delivery and compare status by race and feeding type. STUDY DESIGN Thirty-six (36) preterm (< or =32 weeks gestation) infants (19 black, 17 white) had assessment of feeding type, vitamin D intake, and serum 25-hydroxyvitamin D [25(OH)D] as a marker of vitamin D status at three time points in the first month after delivery. RESULTS Black infants had a significantly lower mean 25(OH)D level on day 7-8 and day 14-15 evaluations than white infants [14.9 +/- 6.6 versus 23.3 +/- 9.3 ng/mL (p = 0.021) and 18.3 +/- 7.3 versus 25.6 +/- 10.3 ng/mL (p = 0.048), respectively], but the difference was no longer significant by day 28-30 evaluation [19.6 +/- 7.7 versus 26.2 +/- 11.6 ng/mL (p = 0.26)]. Vitamin D status was not significantly lower in infants receiving predominantly breast milk (p = 0.6). Vitamin D intake rose through the month as the amount and caloric density of enteral nutrition increased. Six infants had significant decrease in serum 25(OH)D values from day 14-15 to day 28-30 evaluation despite receiving > 400 IU/day vitamin D. CONCLUSION Differences in vitamin D status occurred between black and white infants and were significant through the first 2 weeks after delivery. Infants receiving predominantly breast milk did not have significantly worse vitamin D status than those receiving formula. The significant decline in serum 25(OH)D status observed in 28% of the infants was not related to breast milk intake.
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2634
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Abstract
Exposure to UV radiation is recognized to suppress cell-mediated immunity and therefore could adversely affect the course of a viral infection. Rodent models of viral infection confirm this possibility but the situation in human subjects is not so clear, apart from two exceptions. These are herpes simplex, in which sunlight exposure can cause reactivation, and certain papillomavirus types in which sunlight exposure can lead to the development of nonmelanoma skin cancer. In both cases, there are UV response elements in the viral genomes that alter the normal interactions between the viruses and the host following exposure, and UV-induced effects on the immune response occur in addition. These complex mechanisms are discussed, and the situation regarding UV radiation and viral exanthems plus other viruses, including the retroviruses, summarized. Finally viral vaccination is considered in the context of UV exposure and the importance of the host's genetic background emphasized. Further research is required to evaluate whether sunlight can significantly affect the resistance to common viral infections and vaccines.
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Affiliation(s)
- Mary Norval
- Medical Microbiology, University of Edinburgh Medical School, Edinburgh, United Kingdom.
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2635
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High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study. Breastfeed Med 2006; 1:59-70. [PMID: 17661565 DOI: 10.1089/bfm.2006.1.59] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To examine the effect of high-dose maternal vitamin D(3) (vitD) supplementation on the nutritional vitD status of breastfeeding (BF) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day, respectively. DESIGN Fully lactating women (n = 19) were enrolled at 1-month postpartum into a randomized- control pilot trial. Each mother received one of two treatments for a 6-month study period: 0 or 6000 IU vitD(3) plus a prenatal vitamin containing 400 IU vitD(3). The infants of mothers assigned to the control group received 300 IU vitD(3)/day; those infants of mothers in the high-dose group received 0 IU (placebo). Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly; infant serum vitD and 25(OH)D were measured at baseline, and months 4 and 7. Urinary calcium/creatinine ratios were measured monthly in both mothers and infants. Dietary and BF history and outdoor activity questionnaires were completed at each visit. Changes in skin pigmentation were measured by spectrophotometry. Data were analyzed using chi-square, t-test, and analysis of variance (ANOVA) on an intent-to-treat basis. RESULTS High-dose (6400 IU/day) vitD(3) safely and significantly increased maternal circulating 25(OH)D and vitD from baseline compared to controls (p < 0.0028 and 0.0043, respectively). Mean milk antirachitic activity of mothers receiving 400 IU vitD/day decreased to a nadir of 45.6 at visit four and varied little during the study period (45.6-78.6 IU/L), whereas the mean activity in the 6400 IU/day group increased from 82 to 873 IU/L (p < 0.0003). There were no differences in circulating 25(OH)D levels of infants supplemented with oral vitD versus infants whose only source of vitD was breast milk. CONCLUSION With limited sun exposure, an intake of 400 IU/day vitamin D(3) did not sustain circulating maternal 25(OH)D levels, and thus, supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk. Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation. Thus, a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant.
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