The Immune System And The Body 's Own Healthy Cells

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

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.

Lymphocytes that become part of antibody-mediated immunity arm of the adaptive immune response develop in the:

Our bodies were specifically designed to fight off diseases organically through the use of our immune system. When an antigen enters our bodies, our immune system immediately acknowledges its presence and produces antibodies to fight off the foreign organism. The antibodies will search for the disease organism and will dismantle it when found. The next time the body comes in contact with

Active immunizing agents stimulate the body to make its own antibodies and to continue on making them, 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

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 TH1 response is cell mediated and promotes inflammation while the TH2 response is an antibody response and anti-inflammatory. When excessive, the TH1 response can cause extensive tissue damage. TH1 responses are characterized by IFN-gamma production. IFN-gamma produces macrophage activity and causes B cells to create a coating of Abs. This creates a cell-mediated response. This is effective against invaders that are inside of the host cells. In a cell-mediated response, the APC phagocytizes the invader via macrophage, monocyte, or dendritic cell. Next, the antigen enters the lymphatic system via lymph node. The APC presents the antigen to T cells where the T cells recognize the antigen and cytokines are secreted to search and destroy

The immune system is a network of tissues, cells, and organs which cooperate with each other to shield the body from infectious diseases. When the body is invaded with foreign microbes, the immune system attempts to identify the microbes by triggering responses. When an individual is exposed to the Measles disease, the immune system response results to the patient having a high fever, coughing and having a runny nose. This is an innate response of the body to eliminate fatal infections and diseases. However, this innate response is controlled by the receptors which are embedded in the genes of the individual. Therefore, it is only able to control certain patterns of pathogens and is unable to record new pathogens that enter the body. This is where the adaptive immunity response comes to record all new findings of the invading pathogen and bacteria and the best defence to fight off the infection. The adaptive immunity consists of two different types of cells that defend the body. The T-cell and B-cell receptors have specific roles to help the immune system to defend from infections. The B-cell receptors contain molecules that recognises numerous types of viruses and bacteria. The T-cell receptor has similar molecule structure of relating to immunoglobulins. The difference between the T-cell receptors to the B-cell receptors is the ability to recognise short peptide

Immunotherapy is a form of medical treatment intended to stimulate or restore the ability of the immune system to fight infection and disease. This can be by inducing, enhancing, or suppressing an immune response. Immunotherapies designed to elicit or amplify an immune response are classified as activation immunotherapies, while those that reduce or suppress immune response are suppression immunotherapies. Active immunotherapy has been effective against agents that normally cause acute self-limiting infectious disease. However, a more effective immunotherapy for chronic infectious diseases or cancer requires the use of appropriate target antigens; the

The memory helper T cells last for many years and can respond quickly to the same pathogen, virus or bacteria. The effector helper T cells release a “messenger protein called cytokine” that act as alarms to the immune system (Bauman, 480). The effector helper T cells are what also bind to the antigen on the MHC II B cells. However, the key is that the effector helper T cell has to be specific to the antigen that is presented on the MHC II. So, the B cell and effector helper T cell must be specific to that particular pathogen, virus, or bacteria for the B cell to be activated and then start

This kind of immune response to a persisting pathogen, or direct lysis by the persisting pathogen, causes damage to self-tissue and releases antigen from damaged tissue are taken up by APCs, and this initiates a self-specific immune response. ‘A domino effect can occur, where the non-specific activation of one arm of the immune system leads to the activation of other arms. infection may lead autoimmunity through the processing and presentation of ‘cryptic antigens’. In contrast to dominant antigenic determinants, subdominant cryptic antigens are normally invisible to the immune system. The inflammatory environment that arises after infection can induce increased protease production and differential processing of released self-epitopes by APCs.Bystander activation’ describes an indirect or non-specific activation of autoimmune cells caused by the inflammatory environment present during

Immune privilege sites are regions of the body which are able to tolerate the introduction of foreign antigens without producing an inflammatory response [1]. It is an active process and these sites are believed to have emerged in order to protect susceptible parts of the body which aren’t able to regenerate their tissues and have crucial bodily functions [2].Most likely, inflammation in such body parts could lead to a total loss of function. The type of segregation of immunologically privileged sites from the rest of the body’s immune system can lead to them becoming targets of autoimmune diseases. Immune privilege can be innate, as well as acquired. The feedback from the innate section serves as the first line of defence, and it comprises of a stable connection of resident specialized cells (e.g. astrocytes, microglia etc). These cells encompass the tissues they protect with elongated processes that are sensitive to any changes in that particular environment [27]. The second form of defence is acquired, handled by particular groups of T-cells which able to cross the protective barriers of the tissues. There is an active rejection of cells by CD4 T-cells, even when the cell may display harmful antigens [3], because T-cells become pathogenic if they begin to recognise local

In Chapter 2, I studied the biochemical hallmarks underlying T-cell immunogenicity in context of self/nonself discrimination.

Our immune system is made up of two parts that work together to keep us healthy. The first part is called the innate immune system, it is made up mostly of ‘scavenger’ and ‘killer’ cells that fight off bacterial infections and give the body a general defense against harmful substances. The second part of the immune system is called the adaptive immune system. This part