Introduction
This essay will describe the action of the immune system and discuss the development of autoimmune diseases with a specific focus on Myasthenia Gravis (MG). It will first consider the role of the immune system and its importance. It will then describe what autoimmunity is, and its development. The third part focuses on MG, the physiology behind the disease and compares it to a ‘healthy’ person as well as any causal factors. Finally, some conclusions will be drawn about whether the immune system really is, for or against us.
Role of the immune system
The immune systems role is to protect the body from pathogens.1 Pathogens must first breach the physical barriers of the body to enter the organism.1 These include skin and
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This includes specific and non-specific action. Non-specific immunity includes phagocytosis (Figure 3). This is a process in which a phagocyte with specific receptor will bind to a pathogen with a complementary receptor, this causes the membrane of the phagocyte to wrap around the pathogen, engulfing it to create a phagosome6. A lysosome then fuses with the phagosome and secretes enzymes to hydrolyse the pathogen into peptide chains7. The peptide chains leave the phagosome and join the genes presented on the outside of the membrane of the phagcyte to create a MHC type 2 (major histocompatibility complex).7 The MHC allows specific parts of the immune system to activate.7 The non-specific immune system is important as it prevents the need for the specific immune system which requires more cells and uses more …show more content…
Each T-helper cells have a different receptor so not all types bind to the same MHC14. When a T-helper cell binds to a specific MHC they activate. They also become either memory or effector cells14. When T-helper cells are activated they release a protein called cytokine which is used in cell signalling to alert other activated immunological cells of the infection15.This is the specific immune system and it is important because this type of immunity allows a quicker response each time the same pathogen enters the body this allows the pathogen to be removed
What role does the immune system play in keeping the body safe? Please be very specific [9 pts]
The immune system plays a vital role in helping the body to fight diseases, as well as pathogens, the disease-causing factors. It is mainly composed of the tonsils and adenoids, the lymph nodes and lymphatic vessels, the spleen, appendix, and bone marrow. The main purpose of the immune system is to assist the body in its struggle to maintain optimal health.
The body’s protection against viruses, bacteria and other types of invasions is our immune system (Tortora, 2014).
a. This function is mediated by T cells and B cells (memory cells) in our body via adaptive immunity. The adaptive immune system evolved in early vertebrates and allows for a stronger immune response as well as immunological memory, where each pathogen is “remembered” by a signature antigen. The adaptive immune response is antigen-specific and requires the recognition of specific “non-self” antigens during a process called antigen presentation. Antigen specificity allows for the generation of responses that are tailored to specific pathogens or pathogen-infected cells. The ability to mount these tailored responses is maintained in the body by memory cells. Should a pathogen infect the body more than once, these specific memory cells are used to quickly eliminate it. So basically killer T cells will identify antigens present on foreign cells. These antigens are not found in any of the cells inside our body. Therefore, T cells will identify them and kill them.
The human immune system creates a series of responses in the body to defend the body. If a foreign organism, such as a virus or a cold invades your body, it recognizes these foreign organisms, and, in turn, attacks them to get rid of them. One can think of the immune system as an army of many cells which have set up their own bastion in the human body. They have only one job: To defend. The immune system’s cells are various kinds of white blood cells. The human body typically creates about 1000 million white blood cells on a daily basis. A group of these cells, macrophages, establish a patrol of sorts throughout the body killing germs as soon as they enter the body. However, sometimes an infection can cause the macrophages to succumb to it. The body begins to fight back with stronger T- and B-cells.
Class II MHC: there will not be an immune system. Antigen presentation could not be activated because Class II MHC are created by APC ( antigen presenting cells) and assist with connecting helper T cells with antigens.
The organs that make up the lymphatic and immune system are the tonsils, spleen, thymus gland, lymph nodes, and lymphatic vessels. White blood cells (leukocytes), red blood cells (erythrocytes), plasma, and platelets (thrombocytes) make up the blood. Lymphocytes are leukocytes (white blood cells) that help the body fight off diseases. Two types of lymphocytes are B cells and T cells. Lymphocytes recognize antigens, or foreign substances/matter, in the body. Lymphocytes are a classification of agranulocytes, or cells (-cytes) without (a-) granules (granul/o) in the cytoplasm. B cells are created from stem cells, which are located in the bone marrow. B cells respond to antigens by becoming plasma cells. These plasma cells then create antibodies. Memory B cells produce a stronger response with the next exposure to the antigen. B cells fight off infection and bacteria while T cells defend against viruses and cancer cells. A hormone created by the thymus gland called thymosin changes lymphocytes into T cells. The thymus gland is active when you are a child and slowly shrinks, as you get older. T cells bind to the antigens on the cells and directly attack them. T cells secrete lymphokines that increase T cell production and directly kill cells with antigens. There are three types of T cells: cytotoxic T cells, helper T cells, and memory T cells.
The body fights infection using the immune system, which is made up of millions of cells including T cells and B cells. An important feature of the immune system is that it is much stronger when fighting a disease which it has already fought against before. It has a memory.
Autoimmunity is the failure of the body’s defence system in recognizing its own constituent parts as self, as a result of which an immune response is generated against its own cells and tissues.
Immunology basically involves understanding the immune system and how it responds to various disease conditions. the immune system consists of a number of components. Traditionally, it is divided into humoral and cellular immune responses. It can also be distinguished into innate and adaptive immunity. The innate immunity can discriminate between normal tissues , self and newly encountered non-self-proteins while the adaptive immunity is the more complex system aimed at the eradication of intracellular pathogens. To do this, antigen derived from such pathogens that are often new to the host organism, need to be recognised by receptor-bearing specialised immune cells which respond to a complex system of stimulatory and costimulatory signals. Better understanding of the human immune system has led to the identification of a number of tumor-associated antigens in the 1980s and the development of various immunotherapeutic approaches. In recent years, identification of the specific antigenic MHC class I epitopes, advancements in genetic engineering, gene delivery, and cell-based therapeutic approaches allowed development of the novel immunotherapeutics.
The immune system consists of a defense system that guards the body against invasion from infections and other diseases. Normally, a healthy person's immune system has the capability to differentiate between its own cells and cells that represent threats to the health of the body. (Craft and Kanter, 2002). Autoimmune disease refers to a broad range of over 80 acute, long-lasting diseases that affect nearly every organ in the body. (Wrong Diagnosis.com, 2000).
When the pathogen replicates different components of immune system evolves to protect against various types of pathogens. However infection of an organism does not necessarily shows diseases, disease are only present when the bolus of infection, in terms of when immunity is comprised. All components of
Have you ever wondered how your body works? Did you ever think about how your body defends itself from outside invaders? Remember the last time you were sick. Did you know how your body fought and killed the sickness? All these questions can be answered by learning about one of the most important systems in your body, the immune system.
Specific properties and nature of an immunogen determines its immunogenicity. According to the sixth edition of the textbook Immunology by Kuby, “Immunogenicity is determined in part by four properties of the immunogen: its foreignness, molecular size, chemical composition and complexity, and ability to be processed and presented with an MHC molecule on the surface of an antigen presenting cell or altered self cell.”
Our immune system is the second most complex system in our body. It is made up of organs, cells and proteins that work together to protect our bodies from harmful bacteria, viruses or other microorganisms that can cause diseases. Usually we don’t notice our immune system defending us against pathogens, but if the pathogen (harmful microorganism) is aggressive or if our body hasn’t ever come into contact with it, we can get sick. The jobs of our immune system are to recognise pathogens, as well as neutralise and remove them from our body. Our immune system also has to fight our own cells if they have changed due to an illness, for example, cancer. (1)