Immune response control

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Given the presence of strange agents within their body, the human body triggers a defense response that allows it to continue in a welfare state, but sometimes becomes pathological and extremely deadly. Therefore, the human being has tried to look for how to control an immune response that allows to restore the lost balance.

In 1960, Claman demonstrated that the new humoral immune response requires both the intervention of cells derived from the bone marrow, or B cells, and of thymus cells or T cells. These experiments were performed on irradiated animals, and therefore lacking of immunocompetent cells, to which normal thymus and bone marrow cells were transferred. Thus reconstituted, the animals responded to immunization with ram erythrocytes forming antibodies.

The lymphatic system begins to form towards the end of the fifth week of embryonic life. Lymphatic vessels develop from lymphatic sacks, which arise from developing veins and derive from the mesoderm. The first lymphatic sacks that appear are The pair of jugular lymphatic sacks ; The next to appear is the retroperitoneal lymphatic bag , which is odd. Almost at the same time that the retroperitoneal lymphatic sack develops another sack, the kilo tank . The last to appear is the pair of posterior lymphatic bags . All lymphatic sacks experience the invasion of mesenchymal cells and become groups of lymph nodes. The lymphatic organ that begins lymphocyte production is the fetal liver. The spleen and thymus produce immature cells that are not functional until after birth.

Immune reaction and mediators [ To edit ]

In order to explain how the immune response is controlled, it must be defined that this is a reaction of the agency against an invading agent, called antigen , which is a molecule capable of producing an immune system response by activating lymphocytes and antibody, which is a protein that is responsible for eliminating the antigen through an antigen-antibody complex, where immunocompetent cells also intervene (lymphocytes (lymphocytes B and T), macrophages, dendritic cells, the tumor necrosis factor and antibodies.

The purpose of the immune response is to eliminate the antigen that has invaded the living organism and, thus, restore homeostasis. In order for the immune response to occur, it is necessary that immunocompetent cells such as T and B lymphocytes, macrophages, which are antigen presenters, and interleukins or cytokines, which are secreted by lymphocytes and monocytes intervene.

The macrophages are marked when phagocyte an antigen, and when the T lymphocytes are an adhesion and the B lymphocyte joins the carrier by means of the Hapten receiver. In this way specific proteins are produced against an antigen. If the T lymphocyte is not present in adhesion and lymphocyte B does not join its Hapteno to the bundle, specific proteins are not produced.

Autoimmunity, host graft disease and its control with corticosteroids [ To edit ]

The human body is endowed with immune mechanisms that distinguish the strange thing. Autoimmunity is defined as the impossibility of the organism to recognize their own cells, which entails an immune response against them. It has been possible to distinguish three stages in the response against antigens:

  • Authority: It is a normal regulatory interaction of immune system cells to identify membrane receptors along with MHC molecules and maintain a state of tolerance.
  • Autoimmunity: Increase in reactions against strange material, such as infections.
  • Autoimmune disease: It is the damage to the tissues themselves, which entails a pathology.

Guest graft disease [ To edit ]

An immune reaction of great importance is what is produced in the Guest graft disease , in which the antibodies attack the organ or tissue that has been transplanted. To avoid this, drugs of steroid origin are administered, such as prednisone, or immunosuppressive drugs, such as methotrexate, cyclosporine or sirolimus.

The MHC (major histocompatibility complex) is the one who is in charge of giving or not an answer to particular immunogens by directing it to one place, that the natural immune system recognizes strange invasive molecules by immunoglobulins, T -cell receptors and Glucoproteinic products of the MHC . The MHC is present in all cells while the first two mentioned only in lymphocytes. Upon triggering an immune reaction, a state that puts the life of the person who suffers from it may occur.

This process can be controlled with steroidal drugs such as Prednisone , which is used in autoimmune diseases (the host graft disease, among others), since it acts as an immunosuppressive and reduces the production of antibodies in general. The disadvantage is that it can bring with them the possibility of having more infections due to opportunistic microorganisms.

Another drug that is used as prophylaxis in the face of organ rejection is mycopher , since it is a non -competitive and selective inhibitor of the inosine monophosphate inosine dehydrogenase, important for the synthesis of the guanine nucleotide. This enzyme is important, since B and T lymphocytes need it for proliferation.

He sirolimus It is an immunosuppressive agent that inhibits the activity of a protein with essential action in the coordination of the processes required for the G1 to S pass cell, to interfere in the transduction of the signal caused by the union of the IL2 to its receiver, arresting The T lymphocyte cycle. In this way there is a control of the immune response against the transplanted organ or tissue, since it is prevented that this tissue be attacked by the organism itself.

References [ To edit ]

  • Geffner, Jorge; Fainboim. Introduction to immunology . Edit. Médica Panamericana. Edición. 2007. Pag. 123-134.>
  • Mendez, Huerta. Allergy. Multisystemic disease . Edit. Médica Panamericana. Edición. 2004. Pag. 345-358.>
  • Tortora and recordowski. Anatomy and Physiology . Edit. Oxford. Edición. 2002. Pag. 755.>
  • Sergio A. Zambrano. Immunology . Edit. McCgraw Hill. Edición. 2001. Pag. 153-166.>