Failure of an organism’s immune system to recognize its own constituent parts as self, which allows an immune response against its own cells and tissues, causing self injury.

Lymphocyte that matures in the bone marrow, then matures further into plasma cells & provides humoral immunity. The principal functions of B cells are to make antibodies against antigens, perform the role of antigen-presenting cells (APCs) and eventually develop into memory B cells after activation by antigen interaction. B-lymphocytes tend to fight bacteria.

Biochemical cascade of the innate immune system that helps clear pathogens from an organism. It is derived from many small plasma proteins that work together to disrupt the target cell's plasma membrane leading to cytolysis of the cell. The complement system consists of more than 34 proteins that interact in different complement pathways.  It is involved in the activities of both innate immunity and acquired immunity.

A regulatory protein released by cells of the immune system that acts as intercellular mediators in the generation of an immune response.  Their general function as a class is to regulate the growth & the differentiation & enhance the activation of immune cells.

– T-lymphocytes that when activated by antigen, are able to destroy or remove the infectious microorganism.

Immune cells that’s major function is to process antigen material & present it on the surface to other cells of the immune system. The activated dendritic cell’s function is not to destroy the invader, but to travel with in within the lymphatic vessels to a lymph node. They are present in small quantities in tissues that are in contact with the external environment, mainly the skin & the inner lining of the nose, lungs, stomach & intestines. Similar to a macrophage & resides near it in tissue.

A type of granulocyte that plays a role in allergic reactions and defense against bacterial and parasitic infections. Both basophils & eosinophils are derived from the same precursor cell.

– They assist other white blood cells (both other T-lymphocytes & B-lymphocytes) in the immunologic processes, including maturation of B cells into plasma cells and memory B cells, and activation of cytotoxic T cells and macrophages .  Helper T cells recognize foreign antigen on the surfaces of other cells, then they stimulate B cells to produce antibody and signal killer T cells to destroy the antigen-displaying cells. Subsequently suppressor T cells return the immune system to normal by inactivating the B cells and killer T cells.

– Aspect of acquired immunity that produces antibodies that circulate in the blood & extra-cellular fluids.

Immunity possessed that is present in an individual at birth prior to exposure to a pathogen or antigen.

Treatment of disease by using the immune system to focus treatment of a specific pathogen or targeted cell.

One type of immune cell, specifically white blood cell, which differentiates into B-lymphocytes (bone marrow) or T-lymphocytes (thymus) They play a defense role against bacterial & viral infections.

- A large white blood cell that ingests foreign particles and infectious microorganisms by phagocytosis. Macrophages are the main tissue-resident cell of the immune system. They guard the borders of the potential entry & are found in abundance in many different organs to include: liver spleen, lungs, GI tract & within connective tissue.

Cell surface molecule encoded by a large gene family in all vertebrates.  MHC molecules mediate interactions of leukocytes. MHC determines compatibility of donors for organ transplant as well as one's susceptibility to an autoimmune disease.

A large, circulating white blood cell, formed in  and in the spleen, that ingests large foreign particles and cell debris. They play a role in allergic reactions and defense against bacterial and parasitic infections. Monocytes regularly leave the blood circulation, migrate into tissues, & mature into macrophages.  They are usually < 10% of the total WBC.

Large lymphocytes that are part of the innate immune system with distinctive cytotoxic granules. NK cells are activated when cancer cells display altered surface molecules that differentiate them from the host’s normal, non-cancerous cells.

The ingestion of a smaller cell or cell fragment, a microorganism, or foreign particles by means of the local infolding of a cell's membrane and the protrusion of its cytoplasm around the fold until the material has been surrounded and engulfed by closure of the membrane and formation of a vacuole: characteristic of amebas and some types of white blood cells.

A hypergammaglobulinemia resulting from an increased production of several different immunoglobulins and usually attributable to persistent, high level exposure to antigens, occuring in a wide variety of infectious, inflammatory, and immune-mediated diseases. Most frequently associated with chronic hepatitis, connective tissue diseases & other chronic inflammatory or infectious conditions.

Test that produces a pattern of bands that provides a rough measurement of the different types of immunoglobulins present in the serum.