The Innate Immune System Analysis

Cellular Basis Of Disease: Why has the discovery of Toll-like receptors revolutionised our understanding of how the innate immune system works, and what is the therapeutic potential? The body has two immune systems: the innate immune system and the adaptive immune system. Adaptive, or acquired, immunity refers to antigen-specific defence mechanisms

Humans such as us alike cannot live in a world without a highly effective defense system that helps us to resist against infections and toxins caused by microorganisms. The immune system is a complex network of consorting cells, tissues and organs that defend the body from pathogens and other harmful substances. This essential complex consists of two subsections : the innate immune system and the adaptive immune system.

The immune system is made up of several types of cells that work together to fight infections. Lymph cells (called lymphocytes) are the main type of cell in the adaptive immune system. There are 2 types of lymph cells: T cells and B cells. When B cells respond to an infection, they change into plasma cells. The plasma cells are found mainly in the bone marrow—the soft, inner part of some bones. The plasma cells

The innate and adaptive immune response start with exposure to an antigen in the epithelium of

| | spleen. | | | intestine. | | | bone marrow. | | | lymph nodes. | | | thymus. | Question 6 | Before it can cause disease, a pathogen must first cross ___. | | the lining of the stomach | | | the blood - brain barrier | | | from the blood to a cell | | | an epithelium barrier | Question 7 | Lymphocytes that become part of antibody-mediated immunity arm of the adaptive immune response develop in the:

The immune system is made up of trillions of specialised cells (white blood cells) that detect and destroy pathogens or their toxins. Some white blood cells, which are

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.

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.

Immune system 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

Innate immunity refers to nonspecific defence mechanisms that respond to an antigen's presence in the host body. These mechanisms include physical barriers such as skin, chemicals in the blood, and immune system cells that attack foreign cells in the body. The innate immune response is activated by chemical properties of the antigen.

There are two branches of the immune response: the innate immune response and the adaptive immune response. The innate immune response consists of multiple leukocytes that recognize pathogen associated molecular patterns (PAMPs) [1]. These PAMPs are non-specific, conserved motifs present on a broad range of pathogens, and are recognized through various pattern recognition receptors (PRRs) on leukocytes, which trigger a pro-inflammatory response [1]. Conversely, the adaptive immune response is composed of only two leukocytes, B lymphocytes and T lymphocytes. Both subsets of lymphocytes have the capacity to generate an immune response specific to the invading pathogen [1]. In order for this to occur, the adaptive immune system must be able to recognize specific foreign antigens, as opposed to conserved motifs. Thus, stringent regulation of both B and T lymphocytes must occur in order to prevent recognition of self-antigens as foreign; this process is termed self-tolerance. Self-tolerance occurs through two mechanisms. The first is central tolerance, which takes place in the thymus (T cells) and bone marrow (B cells) [2]. Central tolerance selects for individual B and T cells, which do not recognize self-antigens presented to them in the primary lymphoid organs, to continue maturation [2]. The second is peripheral tolerance, which occurs outside of primary lymphoid organs, where B and T lymphocytes are further selected for self-reactivity to antigens that were not presented to

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.

“Humoral immunity is a type of immune response that depends on antibodies.” The response begins when a pathogen binds to a B cell. The B cell will engulf the pathogen and display a part of the antigen on its exterior. Once a T cell is exposed to the antigen-presenting B cell, the T cell will release proteins to activate the B cell. Now that the B cell is activated, it will produce antibodies to cause the pathogens to clump together. In the last stage of humoral immunity, phagocytes will engulf and destroy the pathogens.

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.

Should New Zealand have mandatory vaccinations? 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