Explain How The Immune System Protects The Body

The main function of the immune system is to protect the body from infectious agents such as viruses and other toxins. The immune system can fail us in two ways-either by becoming under-vigilant, letting infections enter the body, or over-vigilant, so that it is the immune system itself, rather than an infectious agent that causes illness.

The body has two immune systems: the innate immune system and the adaptive immune system.

These experiments tell us that the CD40L on the surface of activated T cells must bind to the CD40 on the macrophage surface to activate the macrophages against Pneumocystis jirovecii organisms.

This journal article was over how our bodies protect us from the internal and external environments. The host has three main “fences” that help with that protection, the skin, the gastrointestinal tract, and the respiratory tract. We are really interesting subjects, the internal and external surfaces of our bodies are constantly being introduced to new bacteria, microbes, and pathogens and yet we do not get sick. The barriers or fences protect us and are crucial for our immune response. There is still much not understood about the immune system but we do know with certainty that when a child is born he or she acquires around two thousand different species of bacteria that really help to get the child immune system started and running. The researchers also know that there is four dominate groups of bacteria phyla’s in the “intestinal niche”, Firmicutes, bacteroidetes, Actinobacteria, and proteobacteria. We are able to have our normal bacteria’s in and on us because our immune system has learned to co-exist with its symbiotic species. As one may wonder or even certainly expect, competition does occur between the host symbiotic organisms and potentially harmful bacterial cells. They compete mainly for nutrients but also for space, some microbes even engage in “chemical warfare” and possibly even killing its rivalry. Inflammatory disorders can possibly arise from the internal and superficial wars going on, that is why the immune system is constantly being monitored for comprises

Lymphocytes are a type of white blood cell, which are an important part of the immune system. Lymphocytes can defend the body against infection because they can distinguish the body’s own cells from foreign ones. Once they recognize foreign material in the body, they produce chemicals to destroy that material. Two types of lymphocyte are produced in the bone marrow before birth.

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 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).

The Immune System The immune system is a network of organs that contain cells which recognize foreign substances and destroys them. All living organisms are exposed to harmful substances and most can protect themselves in several ways, either with physical barriers or chemicals that repel and kill them. It protects vertebrates against viruses, bacteria, fungi and other parasites. These viruses are called pathogens.

Cytotoxic T Cells (CTCs) are comprised of alpha beta chains that have the ability to directly kill infected cells. As a major component of the adaptive immune system, the function of CTCs are to “scan the intracellular environment in order to target and destroy infected cells”. Small peptide molecules, presented on behalf of the entire cell, are transported to the cell surface as pMHC, allowing TCRs on the surface to detect any foreign signals in the method explain above. The diagram below shows how the antigen fragment inside the cell associates with an MHC molecule and is transported to the cell surface. CTC responses to disease are initiated through the interaction between the TCR, and these protein fragments derived from ‘foreign’ invaders that are presented by pMHCI on the surface of infected cells. “The affinity between CD8 and the MHC molecule keeps the T cell and the target cell bound closely together during antigen-specific activation” specially conducted in CTC due to the complex bonds within the CD8. Once a CTL has identified a cell expressing a ‘foreign’ class 1 MHC, the infected cell is eliminated. The structure of the receptors on these CTCs are specialised for this due to its double edged variable region, as shown in the diagram, allowing for additional binding to co receptor CD8, facilitating the phagocytosis on the pathogen if necessary. CDR3 is found on the TCR in CTCs as CTCs interact with a large number of different cell types and recognise a diverse

The body's innate immune response is non-specific and provides the first line of defense against invading pathogens such as bacteria through various receptors that detect bacterial components such as the Toll-like Receptors (TLRs). TLRs are a highly conserved family of proteins that play an important role in pathogen recognition and activation of innate immunity. They are transmembrane proteins that detect different components of a bacterial pathogen. Specifically, Toll-like Receptor 4 (TLR4) detects lipopolysaccharide (LPS) from gram-negative bacteria which leads to an activation cascade of cytoplasmic proteins and transcription factors. This results in the induction of cytokines and chemokines which lead to bacterial clearance by way of neutrophil recruitment. TLR4 uses adaptor proteins MyD88 and Trif to initiate the aforementioned signaling cascade. Despite being a receptor for LPS, TLR4 actually has a weak affinity for LPS while co-receptor CD14 has a strong affinity for LPS. However CD14 lacks a transmembrane domain so it cannot initiate cytoplasmic signaling to activate transcription factors for the induction of cytokines and chemokines. These differing characteristics of the LPS co-receptors necessitated the use of two types of knockout mice, one for each of the receptors.

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.

The circulatory and immune systems are two very closely related systems. The circulatory is composed out of blood vessels, the heart, and blood. The immune system is made up of white blood cells and various lymph nodes. Basically, most of the immune system is found inside the blood of the circulatory system. The circulatory system provides the body with blood. It gives the kidneys of the digestive system something to filter and picks up nutrients from the small intestines. It also picks up air from the lungs of the respiratory system and provides the brain of the nervous system with blood, along with the rests of the body. Protection from wounds in the integumentary system is also provided by the circulatory system which has platelets that aid in blood clotting and forming scabs. The immune system protects all the other systems from disease and helps them from being attacked by viruses and bacteria. It also aids the ears of the nervous system with some very protective earwax. The circulatory system provides us with life fluid while the immune system protects that fluid and the rest of our body.

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 immune system is our body 's defense system – it is vital to our body 's health and survival. We need the immune system to fight off bacteria, viruses, and other foreign, harmful substances - as well as our own cells that have become bad or even cancerous. There are several building blocks that make up the system as a whole, each just as important as the next, that work hand-in-hand. This includes the lymphatic system, biological molecules, antibodies, white blood cells, the tonsils, thymus, bone marrow, and the spleen. The tonsils and thymus both create antibodies, while bone marrow (among other things) creates white blood cells, which are crucial to fighting off infection. The lymphatic system carries waste as well as nutrients, and lymph fluid throughout the body in the blood stream. The lymph nodes act as a strainer or filter, so when the lymph fluid travels through, it traps virus 's, bacteria, and any other substance that 's foreign to your body. These things are then destroyed by lymphocytes, which are specialized white blood cells. The spleen, which also works as a filter, gets rid of aged or damaged platelets and blood cells, and also destroys bacteria and other harmful or foreign substances.

The immune system is made up of a network of cells, tissues, and organs that work together to protect the body. One of the important cells involved are white blood cells, also called leukocytes, which come in two basic types that combine to seek out and destroy disease-causing organisms or substances.