Agglutinins are natural plant carbohydrates that protect the plant from environmental insults, such as bacteria, fungi and insects.

A type of protein produced by the immune system that protects the body from outside substances which the body recognizes as alien such as bacteria, viruses, and foreign substances/ antigens in the bloodstream.

Any structural substance which serves as a target for the receptors of an adaptive immune response. For example, dietary proteins, environmental molecules, chemical molecules. Protein structures than can elicit an immune response.

Any one of a group of proteins in cell membranes that allow the passage of water across the membrane. Aquaporin is found in the astrocytic foot process on the nervous system side of the blood-brain barrier. Aquaporins balance water transport across the blood-brain barrier.

An autoantibody is an antibody (a type of protein) produced by the immune system that is directed against one or more of the individual's self-tissues. Many autoimmune diseases are caused by such autoantibodies.

A self-tissue protein that becomes the target of an immune attack, which, if not addressed, can result in an autoimmune disease.

Cross-Reactivity occurs when an antibody programmed to recognize a specific antigen (for example milk) mistakes another protein (for example brain tissue) as milk and tags the tissue for attack by other immune cells, resulting in autoimmunity against the tissue.

The type of epithelial cell that lines blood vessels and lymph vessels; these cells are usually squamous (flattened) and form sheets one layer thick. A sheet of endothelial cells is called an endothelium. Endothelium makes up the inner layer of vessels such as arteries, veins, and lymphatic vessels. 

A heat-stable toxin associated with the outer membranes of certain gram-negative bacteria, including Brucella, Neisseria, and Vibrio species.

Cells that form a thin surface coating on the outside of a body structure. In relation to Array 2 these are the barrier cells separating the intestinal tract from the body.