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An Introduction to the Immune System and Vaccines
Published in Patricia G. Melloy, Viruses and Society, 2023
Many kinds of cells participate in immunity. One kind is the white blood cell, which is produced in the bone marrow of adults and can be divided into five major categories. These categories include neutrophils, monocytes, basophils, eosinophils, and lymphocytes. Neutrophils and monocytes (which become macrophages) are a part of the innate immune response. For example, macrophages can engulf foreign material using phagocytosis. Basophils and eosinophils are kinds of white blood cells known for the special granules in their cytoplasm. They participate in the response to parasites as well as the allergy response. Lymphocytes include the B and T cells that are a part of adaptive immunity (Nicholson 2016).
The Scientific Basis of Medicine
Published in John S. Axford, Chris A. O'Callaghan, Medicine for Finals and Beyond, 2023
Chris O'Callaghan, Rachel Allen
The innate immune response provides an immediate and relatively non-specific response to challenge. In contrast, the adaptive immune system, involving T cells and antibodies secreted by B cells, requires an initial priming stage followed by cell proliferation when it encounters a target for the first time. Adaptive immunity is highly specific for individual antigens and, following an initial encounter, can persist to provide a memory response.
Introduction to Infection, Resistance, and Immunity
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
The immune system is our primary defense against disease. It is composed of interacting molecules, cells, and organs that can discriminate environmental agents (nonself) from one′s own tissues (self) and prevent or limit the extent to which the body is colonized by nonself. It is important to be aware that there are many components making up the immune system, each with its own set of functions. Some aspects and functions of the immune systems are outlined in Figure 1.1 and are listed below: Constitutive Immunity: (1) Barrier Immunity—Prevents the initial invasion of the body by other organisms. (2) The Inflammatory Response—Rapidly responds to pathogens that bypass barrier immunity and creates conditions that limit their replication at the site of invasion.Adaptive Immunity—Mounts, over a period of several days, immune responses that eliminate invading organisms and their products in a highly specific manner.Passive Immunity—Protects the fetus and newborn from infection during the development of its immune system.
Clinical significance of serum glucose to lymphocyte ratio as a prognostic marker in peritoneal dialysis patients
Published in Renal Failure, 2023
Jiexin Chen, Ruiying Tang, Xiaojiang Zhan, Jihong Deng, Yanxia Zhang, Haibo Long, Fenfen Peng, Na Tian, Yueqiang Wen, Xiaoyang Wang, Xiaoran Feng, Ning Su, Xingming Tang, Xianfeng Wu, Qian Zhou, Qingdong Xu
PD patients show unbalanced lymphocyte metabolism, which is normally tightly regulation by the immune response to glycolysis [19,20], and the expansion and function of T cells may be repressed under high glucose conditions. Malnutrition, accumulation of uremic toxins, and inflammation may lead to the inability to gain adequate nutrients, thereby accelerating the aging process of premature T cells, and causing significant barriers to T cell function in patients with PD [21]. Naïve T cells play a key role in the maintenance of adaptive immunity. Alterations in T cell subsets may attenuate the response to antigens and increase the risk of CVD in patients with kidney failure [22]. CVD mortality is influenced by a variety of factors, including smoking status, blood pressure, cholesterol, and overweight [23,24], while the importance of hyperglycemia and abnormal lymphocyte metabolism should not be ignored.
A standardized extract of Echinacea purpurea containing higher chicoric acid content enhances immune function in murine macrophages and cyclophosphamide-induced immunosuppression mice
Published in Pharmaceutical Biology, 2023
Heggar Venkataramana Sudeep, Kuluvar Gouthamchandra, Illuri Ramanaiah, Amritha Raj, Puttaswamy Naveen, Kodimule Shyamprasad
The term immunity defines the body’s natural defense system against a massive array of diseases and disorders. Surprisingly complicated and advanced among vertebrates, the complex immune system is capable to produce a boundless variety of cells and molecules to block enormous variety of infections and undesirable elements (Patil et al. 2012; Dutt 2013; Sharma et al. 2017). The strategy of avoiding them all may be extraordinarily tricky or difficult and many of the pathogens have mechanisms that allow them to evade the full effects of host defenses. The innate immune responses are generally rapid and independent of immunological memory unlike the adaptive immunity. Innate immune responses include the cellular mechanisms, for example phagocytosis and cytotoxicity, or secretions (cytokines, complimentary factors, antimicrobial peptides, etc.) (Degn and Thiel 2013; Hilchie et al. 2013; Sokol and Luster 2015). Our knowledge of immune functioning is constantly evolving over the years. There exists a paradigm from emerging evidence that the innate and adaptive immunity have mutually interacted and overlapped at times (Gasteiger et al. 2017). With recent advances in the understanding of how cells communicate with each other to signal effector functions, it has become possible to conceive of strategies to manipulate these signaling pathways to influence host responses (Tzianabos 2000). Compounds that can interact with the immune system to upregulate or downregulate specific aspects of the host response can be classified as immunomodulators or biologic response modifiers.
Role of natural killer and B cell interaction in inducing pathogen specific immune responses
Published in International Reviews of Immunology, 2023
Nikunj Tandel, Sushmita Negi, Sarat K. Dalai, Rajeev K. Tyagi
B-cells and the production of antibodies (Abs) have been the part of adaptive immunity. Generation of cognate-antigen specific Abs through B cells, not only activates specific receptors but also induce direct/indirect interaction with the pathogens or T cells, and resulting in stimulation of specific TLRs [72]. On the other side, the reports of experimental evidence indicate that the function of B cells can also be modulated by NK cells. Since humoral immunity is critical as it targets the pathogenic virus to produce antibodies that neutralize the virus and inhibit its progression, antiviral vaccines have been essentially designed to prevent the viral entry into host. Moreover, non-neutralizing antibodies opsonize the virions and present them to professional APCs for further processing, and bind to the virus-derived antigens on viral surface or infected cells that captivate the immune sentinels comprising Fc receptors (mainly NK cells) [73]. Eventually, it kills the antibody-bound target cells through antibody-dependent cellular cytotoxicity (ADCC) of NK cells. Besides, later promotes antibody producing B cells to confer antiviral immunity [74].