Download or read book Effects of Complement Opsonization of HIV on Dendritic Cells written by Rada Ellegård and published by Linköping University Electronic Press. This book was released on 2018-09-28 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dendritic cells are key players during HIV pathogenesis, and shape both the immediate immune response at the site of infection as well as directing the adaptive immune response against the virus. HIV has developed a plethora of immune evasion mechanisms that hijack dendritic cell functions, suppressing their ability to mount an accurate immune response and exploiting them for efficient viral transfer to target T cells. To achieve successful replication within dendritic cells without triggering danger signaling, HIV accomplishes a delicate balance where only a low level of transcription can be sustained without triggering antiviral responses that would harm the virus. Here, we describe how the presence of HSV2 coinfection, which is very common in geographic areas with a high HIV prevalence and almost triples the risk of HIV acquisition, alters dendritic cell state to support much higher levels of HIV infection. We found this effect to be mediated by the STING pathway, which is involved in the sensing of DNA in the cell cytosol. STING activation led to an upregulation of factors such as IRF3 and NFkB that can be used for HIV transcription and a degradation of factors that restrict HIV replication. In addition, we describe how HIV exploits the human complement system, a group of proteins that usually help the human body to identify dangerous pathogens while avoiding reaction towards self. HIV can coat itself, i.e. become opsonized, in complement fragments that are typically only present on the body’s own cells, allowing it to activate signaling pathways that are associated with tolerance. Dendritic cells that come into contact with complement opsonized HIV do not mount danger responses, despite the fact that HIV-derived single stranded RNA triggers the pathogen recognition receptor TLR8. The suppression of danger responses is mediated by activation of complement receptor 3, and leads to an increased infection of the dendritic cell and affects its interactions with other immune cells. There is a lack of recruitment of NK cells to the site of infection, and an inhibition of NK cell killing, which plays an important role in the destruction of HIV-infected cells in vivo. T cells primed by dendritic cells exposed to complement opsonized HIV have a lower ability to develop towards effector phenotype, and have an increased expression of the markers PD1, TIM3 and LAG3 which are associated with T cell dysfunction and exhaustion. In addition, T cells primed by these dendritic cells in the presence of NK cells upregulate markers CD38, CXCR3 and CCR4, which have been linked to an increased susceptibility to HIV infection. In summary, we add to the current knowledge on HIV immune evasion mechanisms that allow the virus to establish infection, as well as describing mechanisms that govern whether dendritic cells mount danger signaling and an immune response or not.
Download or read book Complement Activation Good Or Evil in HIV 1 Infection written by Veronica Tjomsland and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book HIV 1 Exploitation of Dendritic Cell Functionality and Initial Responses in Mucosal Tissues written by Cecilia Svanberg and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book HIV Interactions with Dendritic Cells written by Li Wu and published by Springer Science & Business Media. This book was released on 2012-09-11 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: Given rapid research progress and advance of the techniques in studying HIV interactions with host cells and factors, there is a critical need for a book on HIV interactions with DCs. The proposed book will aim for a broad readership to facilitate HIV/AIDS research and provide a practical tool for HIV researchers to continuously address novel questions. Specifically, the editors will summarize the literature in this field and provide critical analysis and future directions. International researchers will be invited as contributors of the book, highlighting authors who have contributed significantly to the field from different angles and aspects of virology, cell biology and immunology, etc.
Download or read book The Biology of Dendritic Cells and HIV Infection written by Sandra Gessani and published by Springer Science & Business Media. This book was released on 2007-03-09 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dendritic cells play the most vital part in inducing anti-viral immune responses in HIV and AIDS among many other viruses. Research on dendritic cells (DCs) is emerging as a fundamental aspect for the comprehension of the mechanisms underlying the pathogenesis of viral diseases. This volume focuses on the role of DCs in the pathogenesis and immunity of HIV-1 infection. It is the only comprehensive volume on pathogenesis and immunity of Dendritic Cells that also focuses on HIV.
Download or read book Current Perspectives in HIV Infection written by Shailendra K. Saxena and published by BoD – Books on Demand. This book was released on 2013-04-10 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a comprehensive overview of HIV and AIDS including NeuroAIDS, as well as general concepts of pathology, immunity and immunopathology, diagnosis, treatment, epidemiology and etiology to current clinical recommendations in management of HIV/AIDS including NeuroAIDS, highlighting the ongoing issues, recent advances and future directions in diagnostic approaches and therapeutic strategies.
Download or read book The Effect of HIV 1 and Accessory Proteins on Monocyte Derived Dendritic Cell Maturation and Function written by Peter Fairman and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dendritic cells (DCs) are specialized members of the innate immune system that are responsible for the initiation of primary adaptive immune responses whose purpose is to resolve infection and inflammation. During most viral infections, mature dendritic cells present critical viral antigens to naïve T-cells within secondary lymphoid organs, resulting in the generation of an antigen-specific adaptive immune response and clearance of the virus. During infection with HIV-1 however, the virus is not cleared and a chronic systemic infection develops characterized by immune dysfunction, CD4+ T-cell depletion, systemic inflammation, and opportunistic infections. A growing body of evidence indicates that HIV-1 subversion of DCs contributes to both HIV-1 pathologies and viral dissemination. A number of similar effects by accessory HIV-1 peptides on DC physiology have also been reported. In vitro studies demonstrate that HIV-1 inhibits DC maturation and function. Ex vivo studies on the other hand describe partially mature, dysfunctional DCs collecting in secondary lymphoid organs. In vitro studies examining the effects of HIV-1-Tat and HIV-1-Vpr have described opposing effects on DC maturation. Therefore we undertook experiments to comprehensively describe the effects of HIV-1 and the Tat and Vpr accessory peptides on DC maturation and function. To understand the contributions of individual viral proteins to DC dysfunction we infected DCs with a dual tropic HIV-1 and examined phenotypic and functional changes after maturation with inflammatory cytokines. Following this we examined the influence of exogenous and endogenous HIV-1-Tat and HIV-1-Vpr on MDDC maturation and function using recombinant proteins and deletion mutant lab adapted HIV-1 strains. Live dual tropic HIV-1 was found to selectively inhibit aspects of phenotypic maturation as well as antigen capture and presentation functions. MDDC MAPK responsiveness to bacterial LPS remained intact however. Exogenous accessory HIV-1 Tat and Vpr did not affect MDDC phenotype but inhibited dextran endocytosis and viral peptide presentation. HIV-1-gp120 increased iMDDC maturation while blunting cytokine induced decreases in MDDC antigen capture abilities. The deletion of HIV-1-Tat did not affect MDDC phenotype, but was found to affect antigen capture decreases by R5 tropic HIV-1BaL. Deletion of HIV-1-Vpr likewise did not affect MDDC phenotype, however it was found to be influential in HIV-1 induced decreases in MDDC antigen presentation to autologous T-cells. These accumulated results indicate that HIV-1 subverts DC maturation and function through whole virus effects and individual accessory peptide influences. Understanding the mechanisms of DC dysfunction in HIV infection may provide some insight into infection prevention strategies and therapies leading to adaptive immune system activation and viral clearance.
Download or read book IL 23 and IL 27 Expression in Dendritic Cells and the Effects of HIV 1 written by Andréane Chénier and published by . This book was released on 2008 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Role of Complement in Microbial Infections written by Nicole Thielens and published by Frontiers Media SA. This book was released on 2021-04-13 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lymph Node T Cell Dynamics and Novel Strategies for HIV Cure written by Constantinos Petrovas and published by Frontiers Media SA. This book was released on 2019-02-11 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently, more than 36 million people are infected with HIV. Although the introduction of highly active anti-retroviral therapy (HAART) has led to substantial advances in the clinical management of HIV infected individuals, HAART cannot completely eliminate the virus. This is because CD4 T helper cells, harboring the virus, remain dormant reservoirs. These reservoirs are difficult to measure and are present even in HAART-treated HIV infected individuals with undetectable levels of HIV in the blood. A growing body of studies has revealed follicular helper (Tfh) CD4 T cells, a highly differentiated CD4 T cell population localized in immunologically sanctuary sites (follicle/germinal center), as a major reservoir of HIV. The present Frontiers in Immunology eBook compiles 16 timely review articles focusing on the dynamics of major follicular immune cell types in HIV/SIV infection and their potential role for disease pathogenesis and the viral persistence in the lymph node. This eBook provides a comprehensive presentation of recent published work on lymph node and especially Tfh cell dynamics in HIV infection and we hope that it will be useful for our further understanding of how such dynamics affect the interplay between virus and host as well as for the discovery of novel therapeutic targets in the fight against HIV.
Download or read book Janeway s Immunobiology written by Kenneth Murphy and published by Garland Science. This book was released on 2010-06-22 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Janeway's Immunobiology CD-ROM, Immunobiology Interactive, is included with each book, and can be purchased separately. It contains animations and videos with voiceover narration, as well as the figures from the text for presentation purposes.
Download or read book Antibody Fc written by Margaret A. Lindorfer and published by Elsevier Inc. Chapters. This book was released on 2013-08-06 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: The key roles of the complement cascade and cellular Fcγ receptors in the innate and adaptive immune system are well documented. Recognition of soluble or cell-bound IgG-containing immune complexes by either of these two respective effector systems leads to a complex series of separate and non-overlapping inflammatory reactions and cytotoxic processes, each of which serves to remove or destroy opsonized microorganisms or targeted tumor cells. Alternatively, in autoimmune diseases these reactions mediate severe pathologies which are manifested in local or systemic inflammation as well as in tissue injury. For some time, it appeared that these two effector systems functioned independently and did not communicate; however, increasing evidence reveals synergy and feedback control between these two systems. Indeed, danger signals can alert one system leading to cross-communication and cooperation with the other to efficiently eliminate the threat. On the other hand, undesired and deleterious inflammation can be controlled by FcγR-mediated suppression of complement.
Download or read book Adverse Effects of Vaccines written by Institute of Medicine and published by National Academies Press. This book was released on 2012-04-26 with total page 894 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1900, for every 1,000 babies born in the United States, 100 would die before their first birthday, often due to infectious diseases. Today, vaccines exist for many viral and bacterial diseases. The National Childhood Vaccine Injury Act, passed in 1986, was intended to bolster vaccine research and development through the federal coordination of vaccine initiatives and to provide relief to vaccine manufacturers facing financial burdens. The legislation also intended to address concerns about the safety of vaccines by instituting a compensation program, setting up a passive surveillance system for vaccine adverse events, and by providing information to consumers. A key component of the legislation required the U.S. Department of Health and Human Services to collaborate with the Institute of Medicine to assess concerns about the safety of vaccines and potential adverse events, especially in children. Adverse Effects of Vaccines reviews the epidemiological, clinical, and biological evidence regarding adverse health events associated with specific vaccines covered by the National Vaccine Injury Compensation Program (VICP), including the varicella zoster vaccine, influenza vaccines, the hepatitis B vaccine, and the human papillomavirus vaccine, among others. For each possible adverse event, the report reviews peer-reviewed primary studies, summarizes their findings, and evaluates the epidemiological, clinical, and biological evidence. It finds that while no vaccine is 100 percent safe, very few adverse events are shown to be caused by vaccines. In addition, the evidence shows that vaccines do not cause several conditions. For example, the MMR vaccine is not associated with autism or childhood diabetes. Also, the DTaP vaccine is not associated with diabetes and the influenza vaccine given as a shot does not exacerbate asthma. Adverse Effects of Vaccines will be of special interest to the National Vaccine Program Office, the VICP, the Centers for Disease Control and Prevention, vaccine safety researchers and manufacturers, parents, caregivers, and health professionals in the private and public sectors.
Download or read book C Type Lectin Receptors in Immunity written by Sho Yamasaki and published by Springer. This book was released on 2016-03-22 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents the latest findings on C-type lectin receptors, focusing on individual receptors and their signaling. In recent years there have been great advances in the understanding of the function of these receptors as a newly emerging family of pattern-recognition receptors (PRRs) for pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Comprising four parts: ITAM-coupled Activating Receptors; HemITAM-bearing Receptors; ITIM-bearing Receptors; and Other Receptors and Related Topics, this comprehensive review covers a broad range of C-type lectin receptors. The updated information on C-type lectin receptors and their ligands provided will appeal to a wide readership, from basic immunologists to physicians and surgeons. In addition, sections on novel drug development make this a valuable resource for pharmaceutical scientists.
Download or read book Antibody Fc written by Margaret Ackerman and published by Academic Press. This book was released on 2013-08-06 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antibody Fc is the first single text to synthesize the literature on the mechanisms underlying the dramatic variability of antibodies to influence the immune response. The book demonstrates the importance of the Fc domain, including protective mechanisms, effector cell types, genetic data, and variability in Fc domain function. This volume is a critical single-source reference for researchers in vaccine discovery, immunologists, microbiologists, oncologists and protein engineers as well as graduate students in immunology and vaccinology. Antibodies represent the correlate of protection for numerous vaccines and are the most rapidly growing class of drugs, with applications ranging from cancer and infectious disease to autoimmunity. Researchers have long understood the variable domain of antibodies, which are responsible for antigen recognition, and can provide protection by blocking the function of their target antigen. However, recent developments in our understanding of the protection mediated by antibodies have highlighted the critical nature of the antibody constant, or Fc domain, in the biological activity of antibodies. The Fc domain allows antibodies to link the adaptive and innate immune systems, providing specificity to a wide range of innate effector cells. In addition, they provide a feedback loop to regulate the character of the immune response via interactions with B cells and antigen-presenting cells. - Clarifies the different mechanisms of IgG activity at the level of the different model systems used, including human genetic, mouse, and in vitro - Covers the role of antibodies in cancer, infectious disease, and autoimmunity and in the setting of monoclonal antibody therapy as well as naturally raised antibodies - Color illustrations enhance explanations of the immune system
Download or read book Molecular Biology of the Cell written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Harnessing the Participation of Dendritic Cells in Immunity and Tolerance written by Silvia Beatriz Boscardin and published by Frontiers Media SA. This book was released on 2020-12-10 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
