Innate Immune Response Paper

A T cell are also referred to as T lymphocytes which are key cells of specific immunity as referenced by Krasner and Shors.

Describe how and why both types of adaptive immunity can cause problems with organ transplantation.

When a virus invades the human body there is an assortment of responses from the immune system relying largely on the particular pathogen type. Viruses invade the host with the purpose of replication to ensure survival. My cytosolic virus is a single stranded RNA virus. The virus is surrounded by an envelope with a lipid membrane. Inside the envelope are matrix proteins, integrase, protease, reverse transcriptase and the RNA genome. All viruses contain three proteins necessary for their survival; one for replication, one for packaging and delivering it to more host cells and a protein that modifies the function or structure of the host

Natural killer T cells (NKT), not to be confused with Natural Killer cells or killer T cells (CTL), are a heterogeneous subset of T cells recognized by their unique innate and adaptive molecular characteristics and markers. Perhaps the most defining characteristic of natural killer T cell is the ability to recognize lipid antigens in the context of CD1d molecules, associated to β2-microglobulin (Laurent, Renault, Farce, Chavatte, & Hénon, 2014). CD1d molecules are predominantly expressed by Antigen Presenting cells, particularly Marginal Zone B cells (MZB). NKT cells have been divided into two main subsets: type I NKT cells that use a canonical invariant TCR α-chain and recognize α-galactosylceramide (α-GalCer), a powerful antitumor stimulant, and type II NKT cells that use a more diverse αβ TCR repertoire and do not recognize α-GalCer (Macho-Fernandez & Brigl, 2015. Notably, α-GalCer-activated Type I NKT cells are capable of substantial crosstalk with other cell types of the innate and adaptive immune systems (Matsuda et al. 2008; Parekh et al. 2007). However, Type II NKT cells display more of a heterogeneous TCR and lack Vα14-Jα18 rearrangement, thus the reason for their inability to recognize α-GalCer. Conversely, type II NKT cells recognize a naturally occurring self-glycolipid and sulfatide, which is enriched in several membranes, including myelin in the central nervous system (CNS), β-cells in the pancreas, kidney, and liver (Marrero, Ware, & Kumar,

The main aim of the immune system is to limit and dispose any harmful waste products as well as evacuating the damaged tissues so that the body can begin healing. The body’s self-protective reaction comprises of variations in the blood stream to take in an increased discharge of fluids from the veins together with an increase of plasma, T-lymphocyte cells, proteins and phagocytes to enter the tissue so as to heal the damaged area as well as fighting off bacteria and viruses. The T and B cells are the most important cellular elements of the adaptive immune response. When a person is stressed, the ability of the immune system to attack antigens is usually reduced and one becomes more vulnerable to infections. T and B cells may play a significant neuroprotective role in both stress and inflammation. Through their

I understand how to use representations or models to analyze quantitatively and qualitatively the effects of disruptions to dynamic homeostasis in biological systems. Both models and representations may be used to show the effects of changes in homeostasis. The main ways to achieve homeostasis is through positive and negative feedback and disruptions can be viewed easily through models or representations. (Campbell 644-645, 650-652)

The increase of fish meal and fish oil prices has urged aquaculture companies to use alternative ingredients for feed production. However, nutritional imbalances caused by the replacement of marine ingredients can reduce growth rates, and may also alter the immune response or reared fish. In this study we aimed to evaluate the effects of an extensive replacement of dietary fish meal and oil by plant and animal ingredients on the immune response of Atlantic salmon. During a 14-week trial, Atlantic salmon were fed a fish meal-fish oil based diet (FM), a diet based on plant protein and oil (VEG), and a vegetable oil-based diet with animal by-product meal as major protein source (ABP). At the end of the trial, salmon were injected with either phosphate-buffered

The systemic response results in a variety of pathophysiolocigal changes aimed at repairing the injury (Whicher and Westacott, 1992), and it is accompanied by the hepatic synthesis and release of several plasma proteins, known as acute phase proteins (APP) (Baumann and Gauldie, 1990), which initiate the anti-inflammatory process through a wide range of biological functions. The pattern of responding APP varies between animal species, and they are classified as major, moderate, minor and negative APP based on their increase in plasma (Murata et al., 2004). Positive associations have been established between circulating concentrations of specific APP and the extent of particular disorders in different species, which support their potential use as health markers in animals. Nevertheless, they act as non-specific markers, as they do not clarify the etiology of disease (Petersen et al., 2004) but are able to disclose the presence of inflammatory lesions, whether they are primary or secondary to other disorders (Eckersall, 1995).

Analysis of data showed that there was a higher percentage of macrophages than B cells present within the MHC positive population. The remaining population of cells (3%) can be attributed to dendritic cells, which have been previously shown to form a small percentage (3%of cells) within zebrafish gut by Wittamer et al, 2011. While we used visual morphological differences to distinguish between B cells and macrophages, future experiments can make use of the mhc2dab:GFP; cd45:DsRed double-transgenic (Wittamer et al,2011) which would enable us to distinguish between macrophages (mhc+; cd45+) and B cells (mhc+) through fluorescent markers thereby allowing us to FACS sort pure populations if needed as well. We saw that within the mhc+ cells in the wild-type zebrafish gut, phagocytosis by macrophages within gut phagocytes was higher than B cells.This high proportion of phagocytosis by macrophages within leukocyte populations is consistent with Page et al’s, 2013, in-vivo study in which more than half of the phagocytic cells in murine peritoneal cavity were macrophages. We further quantified phagocytic efficiency of each cell type within their respective populations. 54.5% of macrophages within the macrophage population were phagocytic and 33.8% of B cells within the B cell population were phagocytic. Interestingly, previous research by Li et al, indicated that teleost fish can show up to 60% of phagocytic behaviour by B cells. However, in contrast, a study by Page et al, showed only a 2% phagocytic efficiency of zebrafish B cells. While the researchers acknowledge that there is a possibility that intrinsic experimental conditions could have contributed to this result, it should also be noted that the in-vitro experiment used B cells from the kidney to test for phagocytic efficiency. B cells from the gut may have

During evolution process, most organisms have established a sophisticated immune system to protect and clear the invading pathogens. The immune system of vertebrates has been divided into innate and adaptive immune system, although, emerging evidences have shown the interplay between the two. The innate immune system comprises physical barriers, cellular components and humoral responses that can be activated in the early phase of infection upon interaction with foreign antigens as immediate response against them and further helps to shape adaptive immune response on the basis of the nature of stimulant by activating the components of the adaptive immunity. The vertebrate innate immune system relies on pattern recognition receptors

Mucosal surfaces are the main route of entry for pathogens in all living organisms. In the case of teleost fish, mucosal surfaces cover the vast majority of the animal. As these surfaces are in constant contact with the environment, fish are perpetually exposed to a vast number of pathogens. Despite the potential prevalence and variety of pathogens, mucosal surfaces are primarily populated by commensal non-pathogenic bacteria. Indeed, a fine balance between these two populations of microorganisms is crucial for animal survival. This equilibrium, controlled by the mucosal immune system, maintains homeostasis at mucosal tissues. Teleost fish possess a diffuse mucosal-associated immune system in the intestine, with B cells being one of the main responders. Immunoglobulins produced by these lymphocytes are a critical line of defense against pathogens and also prevent the entrance of commensal bacteria into the epithelium. In this review we will summarize recent literature regarding the role of B lymphocytes and immunoglobulins in gut immunity in teleost fish, with specific focus on immunoglobulin isotypes and the microorganisms, pathogenic and non-pathogenic, that interact with the immune system.

Blood analysis in veterinary practice is a valuable testing to address diagnosis of a large number of conditions in farm and companion animals. Combined with the history, records and clinical examination of patients, it provides useful information to formulate a clinical suspicion and it may sometimes offer precise clues of specific disease or its nature. For example, changes in the number and morphology of red blood cell count might aid in the diagnosis of different types of anemia, whereas modification of white blood cell count may support the presence of acute or chronic inflammation or infection or of immunoproliferative disorders. Alongside of traditional hematologic analyses, considerable progress has been made in the understanding of acute phase response in veterinary medicine over recent years, to the point that measurement of acute phase proteins has proved as a powerful tool to enhance clinical evaluation in domestic animals for diagnostic, monitoring and prognostic purposes (Eckersall and Bell, 2010). The acute phase response (APR) is the dynamic process involving systemic early-defense mechanisms acting to restore homeostasis and promote healing following systemic or local disorders. It represents the non-specific, innate response of the body before the development of specific immunity to a challenge. It is activated by specific cytokines following different stimuli, including trauma, surgery, inflammation, infection, stress and neoplasia (Cray et al., 2009;

The immune system is comprised of two responses: the adaptive immune response and the innate immune response. The first line of defence against invading organisms is classified as the innate immune response and the second line of defence and protection against re- exposure to the same pathogen is known as the adaptive immune response.

The immune response to viral and bacterial pathogens is well studied using mathematical models cite{antia2005role,perelson2002modelling,marchuk2013mathematical} and the role of mathematical models in understanding the immune response is evident cite{antia2005role}. Mathematical models have contributed to our understanding of dynamics of CD8 response, memory generation, disease progression, and viral escape. Classical models of immune response are based on simple ordinary differential equations involving density or number of invading pathogen and many cell types of immune system. The dynamics of CD8 T cell response thus generally follow a predator prey relationship. Many models of immune response has been developed cite{nowak2000virus,wodarz2007killer} and the role of mathematical models is reviewed in detail cite{perelson2002modelling,antia2005role,yewdell2004immunodominance,beauchemin2011review,perelson2013modeling}. Various mathematical approaches in practice to understand the complexity of immune response and its regulatory mechanisms have been reviewed cite{kim2009modeling,bianca2012immune}.

In today’s society, molecular understanding of functions, like interleukin 2, has contributed to the physiological comprehension of immune responses in life forms. Interleukin-2 is a crucial factor in the fight against HIV/AIDS and other immunosuppressant diseases. It binds itself to T cell receptors which induce naive T cell proliferation and differentiation. This contributes to a plethora of different cells such as cytotoxic T cells, natural kill cells, and LAK cells, which protect life forms against infections and/or viruses. In 1993, an immunological analysis was performed by Sadlack and his colleagues. Knockout mice were used, meaning that their IL-2 gene was removed. This resulted in an increased amount of T and B cell counts relative to the wild type mice. These researchers thus suggested that it is an inflammatory regulator. Overall when IL-2 is not present, unregulated proliferation of T cells increase as mice reach their terminal stage of illness. Now, interleukin-2 is used in HIV therapies, which helps increase and regulate T cell reactions in immune compromised patients. Data has been shown that IL-2 increases proliferation and survival of CD4+ T cells in these patients.