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Leukocyte culture conferences have a long pedigree. This volume records some of the scientific highlights of the 16th such annual con ference, and is a witness to the continuing evolution and popularity of leukocyte culture and of immunology. There is strong evidence of the widening horizons of immunology, both technically, with the obviously major impact of molecular biology into our understanding of cellular processes, and also conceptually. Traditionally, the 'proceedings' of these conferences have been published. But have the books produced really recorded the major part of the conference, the informal, friendly, but intense and some times heated exchanges that take place between workers in tackling very similar problems and systems and which are at the heart of every successful conference? Unfortunately this essence cannot be incorpo rated by soliciting manuscripts. For this reason, we have changed the format of publication, retaining published versions of the symposium papers, but requesting the workshop chairmen to produce a summary of the major new observations and areas of controversy highlighted in their sessions, as a vehicle for defining current areas of interest and debate. Not an easy task, as the workshop topics were culled from the abstracts submitted by the participants, rather than being on predefined topics. The unseasonal warmth in Cambridge was reflected in the atmos phere of the conference, the organization of which benefited from the administrative skills of Jean Bacon, Philippa Wells, Mr. Peter Irving, and Mrs.

The world continues to lose more than a million lives each year to the HIV epidemic, and nearly two million individuals were infected with HIV in 2017 alone. The new Sustainable Development Goals, adopted by countries of the United Nations in September 2015, include a commitment to end the AIDS epidemic by 2030. Considerable emphasis on prevention of new infections and treatment of those living with HIV will be needed to make this goal achievable. With nearly 37 million people now living with HIV, it is a communicable disease that behaves like a noncommunicable disease. Nutritional management is integral to comprehensive HIV care and treatment. Improved nutritional status and weight gain can increase recovery and strength of individuals living with HIV/AIDS, improve dietary diversity and caloric intake, and improve quality of life. This book highlights evidence-based research linking nutrition and HIV and identifies research gaps to inform the development of guidelines and policies for the United Nations’ Sustainable Development Goals. A comprehensive approach that includes nutritional interventions is likely to maximize the benefit of antiretroviral therapy in preventing HIV disease progression and other adverse outcomes in HIV-infected men and women. Modification of nutritional status has been shown to enhance the quality of life of those suffering HIV/AIDS, both physically in terms of improved body mass index and immunological markers, and psychologically, by improving symptoms of depression. While the primary focus for those infected should remain on antiretroviral treatment and increasing its availability and coverage, improvement of nutritional status plays a complementary role in the management of HIV infection.

Active vitamin D ligand, 1alpha,25-dihydroxyvitaminD (1,25D), binds to the vitamin D receptor (VDR), and the ligand-activated complex further regulates transcription of various genes within the target cell. Thus, cells that express the VDR are vitamin D targets. VDR is expressed in immune cells including dendritic cells, macrophages, neutrophils, T cells and B cells. Danger signals such as lipopolysaccharide (LPS), interferon (IFN)-gamma and activation of T and B cells have been shown to regulate the expression of the VDR, implicating its role in modulating immunity. VDR polymorphisms and vitamin D deficiency in humans have been associated with the increased risk of autoimmune diseases such as inflammatory bowel diseases (IBD) and higher susceptibility to both bacterial and viral infections. Identification of vitamin D targets in the immune system and modifying the host immune response through regulation of vitamin D levels is of great clinical significance. We utilized a novel transgenic reporter mouse to lineage trace immune cells that express the VDR. Our data show that both innate (macrophages, monocytes, neutrophils) and adaptive (B and T cells) splenic immune cells expressed tdTomato. Innate lymphoid cells (ILC) 1 and 3 in lungs, small intestine, and colon expressed tdTomato while ILC2 cells did not. Bone marrow (BM) hematopoietic progenitors and thymic T cell progenitors were predominately positive for tdTomato. Peripheral immune cells and their developmental progenitors are tdTomato+ and therefore targets of vitamin D. We sorted tdTomato+ and tdTomato- T cells and studied their response in vitro. Activated tdTomato- T cells did not become tdTomato+, the tdTomato- T cells proliferated faster and produced more IFN-gamma as compared to tdTomato+ T cells. Thus, tdTomato+ and tdTomato- T cells are functionally distinct. Due to the high expression of tdTomato noted in BM progenitors, we further wanted to investigate whether VDR+ and VDR progenitors can be detected earlier in development. tdTomato expression was found in the fetal liver and fetal thymus at embryonic (E) day E15.5. Maternal vitamin D deficiency affected the frequency of fetal hematopoietic progenitors and tdTomato expression, suggesting that the availability of maternal 25-hydroxyvitaminD is needed for fetal liver hematopoiesis and thymopoiesis. Vitamin D deficiency also affected the frequency of tdTomato+ T cells in the spleen and ILCs in the lungs of mice post-birth, highlighting that VDR+ lineage continues to develop after birth. VDR knockout (KO) embryos showed fewer hematopoietic progenitors, while VDR KO adult mice had more hematopoietic progenitors. The effects of vitamin D deficiency (D-) and oral supplementation with vitamin D3 (cholecalciferol) on the outcomes of H1N1 influenza and SARS-CoV-2 infection in animal models was determined. D- mice experienced higher respiratory distress post H1N1 infection. Mice with deletion of Cyp27B1 gene and inability to produce 1,25D had decreased survival post H1N1 infection. SARS-CoV-2 infection induced the expression of vitamin D related genes in the lungs of infected mice. High dose vitamin D3 supplementation reduced lung inflammation in mice infected with SARS-CoV-2. Thus, vitamin D and vitamin D receptor play important roles in development and function of the immune system.

Research and clinical application of vitamin D has increased dramatically over the past decade stimulated by novel health promotion discoveries and documentation. This book brings together key researchers with their views focusing on the health promotion role of vitamin D. Such information is vital to clinicians, users of vitamin D supplements of all ages and those interested in public policy. The authors document and define many of the key health related roles of vitamin D. Its traditional application in bone and muscle health as well as therapy of arthritis is expanded and clarified with new research. A better understanding of the effects of vitamin D inadequacy is modelled using problems ranging from infant growth retardation to chronic kidney and periodontal disease. Uniquely the vitamin?s role in resistance and treatment of infectious diseases is shown in examples ranging from HIV/AIDS to tuberculosis. Mechanistic understanding of vitamin D's actions is enhanced by looking into its effects on immune modulation and inflammation. Expansion of the role of sunlight in stimulating vitamin D production is discussed relative to the reduction in a variety of cancers. Clearly vitamin D is like a two edged sword with great benefits but also some risks. This book provides carefully defined examples of both situations.

Vitamin D: Volume 2: Health, Disease and Therapeutics, Fourth Edition, authoritatively covers the evidence for new roles for vitamin D, ranging from cardiovascular disease, to cancer, diabetes, inflammatory bowel disease, multiple sclerosis and renal disease. This collection represents a who's who of vitamin D research and the coverage is appropriately broad, drawing in internal medicine, orthopedics, oncology and immunology. Clinical researchers will gain a strong understanding of the molecular basis for a particular area of focus. - Offers a comprehensive reference, ranging from basic bone biology, to biochemistry, to the clinical diagnostic and management implications of vitamin D - Saves researchers and clinicians time in quickly accessing the very latest details on the diverse scientific and clinical aspects of Vitamin D, as opposed to searching through thousands of journal articles - Chapter authors include the most prominent and well-published names in the field - Targets chemistry, metabolism and circulation, mechanisms of action, mineral and bone homeostasis and vitamin D deficiency - Presents a clinical focus on disorders, analogs, cancer, immunity, inflammation, disease and therapeutic applications