Immune Health Glossary

Acquired (Adaptive) immune system – one of two parts of the immune system, characterized by a slower response to the first encounter with an infection and then a rapid-recall memory for any future encounters with the same infection.

Antibody – a factor secreted from B cells that either alone or in cooperation with phagocytes can neutralize the ability of pathogens to infect the body.

B cells – one type of lymphocyte generally considered part of the adaptive immune system. B cells have two main functions in adaptive immunity; to secrete antibodies and to help activate other cells of the immune system to defend the body.

Beta glucan – polymer of glucose (sugar) molecules attached in a specific conformation. Beta glucans can come from different source such as cereals (oats and barley) and fungi such as mushroom and yeast.

Complement – a system of proteins that are present in blood that act together to defend the body against pathogens.

CR3 receptors protein on the surface of many immune cells including neutrophils which when bound to beta glucan helps to prime the neutrophils to respond to infectious challenges.

Complement Receptor –  a protein on the surface of a cell that binds to activated complement proteins.

Dendritic cells – cells whose main function is to show (present) small parts of potential pathogens to other immune cells in order to activate the body’s defenses.

Hygiene Hypothesis – as described in Janeway’s Immunobiology 8th Ed., “a hypothesis first proposed in 1989 that a change in exposure to ubiquitous microorganisms was a possible cause of the increase in allergy.”

Immune response – action taken by the body to defend against a potential pathogen.

Immune system – The tissues, cells, and molecules involved in innate immunity and adaptive immunity. (Janeway’s Immunobiology, 8th Ed.)

Immunonutrition – the nutrients required for proper functioning of the immune system, generally in addition to normal nutritive requirements for the human body.

Immunosuppression – physiological state of the immune system in which immune response is greatly diminished or absent.

Innate immune system – one of two parts of the immune system, characterized by a rapid and broad response to infections with no “memory” capability when the same infection is encountered subsequently.

Lymphocyte cells – cellular components of the adaptive immune system including B and T cells.

M-Cells – cells located in the immune tissue of the intestines which are specialized to continuously sample the contents of the intestines in order to alert the body to potential pathogens.

Macrophage – cells important in both innate and adaptive immunity that engulf potentially infectious agents and trigger innate and adaptive immune responses.

Natural killer (NK) cells – a type of immune cell which is able to directly kill virally-infected cells and/or cancer cells, generally not thought to have a memory function and therefore are considered part of the innate immune system.

Neutrophil – a type of immune cell that is the major effector cell type in the innate immune system. Neutrophils kill microorganisms by engulfing them and digesting them with enzymes and chemicals.

Oxidative burst – method through which some cells of the innate immune system, including neutrophils, produce anti-microbial chemicals.

Peyer’s Patches – areas in the gut which contain a grouping of many different types of immune cells, which is very important for initiation of an immune response in the gut.

Phagocyte – any immune cell that can engulf (“eat”) another cell, includes neutrophils.

Prime – to make ready for action without complete activation of an immune response. 

T-Cells – one type lymphocyte cell that is part of the adaptive immune system. The two main types of T cells, helper and  killer T cells, are responsible for cell-mediated adaptive immune responses in the body.