The following are some of the major terms used in immunology that you should keep in mind, as these are the basic ones and will be used most frequently.
- Immune system: a group of cells, cell products ,organs that provide resistance against foreign bodies (antigen). Cells include B-lymphocytes , T-lymphocytes, products of various cells, macrophages dendritic cells and many more. among the organs Thymus, Spleen, and bone marrow, and secondary lymphatic tissues such as spleen, tonsils, lymph vessels, lymph nodes.
- Antigen: any substance (usually a protein or carbohydrate) capable of inducing an immune response.
- Epitope: part of an antigen recognized by the immune system.
- Antibody (Immunoglobulins) : a Y-shaped protein found in the blood or other bodily fluids produced by the B cells in response to an antigen.
- B-lymphocytes (B-cells): they are a type of white blood cells that function in the humoral immunity component of the adaptive immune system by secreting antibodies. They are produced in the bone marrow.
- T-lymphocytes (T-cells): these are a type of white blood cells that function in he cell-mediated immunity component of the immune system. these are distinguished by the other cells by the presence of the TCR (T-cell receptor) and produced in the bone marrow but migrate to the thymus for maturation. these are of 2 types t-helper cells and t-cytotoxic cells.
- T-Cell receptor: these are the heterodimeric antigen receptor of the T lymphocyte hat is responsible for recognizing fragments of antigen as peptides bound to major histocompatiblity complex (MHC) molecules.
- Humoral immune response: immune response caused by the b-cells activation (activated by the T-helper cells) for the destruction of the antigen. they differentiate into memory b cells and plasma cells (they have the ability to secrete antibody)
- Cell mediated immunity : it is another component of adaptive immunity but it does not produce antibodies rather it release various cytokinin in response to an antigen. T-cells are a central part of cell mediated immune system.
- Immunodeficiency : inability of body from fighting diseases and infections. Eg: DiGeorge syndrome , SCID (sever combined immunodeficiency)
- Autoimmunity: when the immune system of an organism work against its own cells i.e. it considers its self cells as non-self/ antigen and cause the destruction of that particular tissue/cell/organ. Eg: Grave’s disease
- vaccines: a biological preparation of killed attenuated or live microorganism that help in enhancing immunity against diseases
- Antigen presenting cells (APC): these cells display antibody complexed with major histocombatiblity complex (by the process antigen presenting)
- Major Histocompatiblity Complex (MHC) : is a set of cell surface proteins that help the immune system distinguish between harmful and safe foreign substances in the body.