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Found Antigen 164 times.

Displaying results 1 to 10.

1. ABO blood group (blood type, blood typing)
A system of describing the oligosaccharide antigen s found on the surface of human blood cells. According to the type of antigen present, a person may be assigned a blood type of A, B, AB or O. A second type of antigen, the Rh factor , renders a "positive" or "negative" blood type. The ABO blood group system is important because it determines who can donate blood to or accept blood from whom. Type A or AB blood will cause an immune reaction in people with type B blood, and type B and AB blood will cause a reaction in people with type A blood. Conversely, type O blood has no A or B antigens, so people with type O blood are "universal donors." And since AB blood already produces both antigens, people who are type AB can accept any of the other blood types without suffering an immune reaction. The ABO system is also important because it can be used in paternity suits to rule out whether a man is the father of a certain child or not.

2. Absorption
The process of absorbing; specifically: * In physiology, it refers to the movement of liquids and solute s into cells by way of diffusion or osmosis. * In chemistry, it refers to the drawing of a gas or liquid into the pores of a permeable solid. * In immunology, it refers to a process in which an antigen or antibody is used to pull an analogous antigen or antibody out of a solution. Compare adsorption .

3. Acellular vaccine
Vaccine consisting of antigenic parts of cells.

4. Adjuvant
* In pharmacology, a substance that, when added to a medicine, speeds or improves its action. * In immunology, a substance that is added to a vaccine to improve the immune response so that less vaccine is needed to produce more antibodies. Such adjuvants apparently work by speeding the division of lymphocytes and by keeping the antigen in the area where the immune response is taking place. In research with humans, aluminum phosphate and aluminum hydroxide gel are commonly used; in research involving lab animals, Freund's adjuvant is used.

5. Affinity
Attraction between particles or substances to other particles or substances. In biological and biochemical fields, this term generally is a measure of the attraction of one biological molecule toward another molecule (which can be organic or inorganic), either to alter it, destroy it, or form a compound with it. Examples are enzyme s and their substrate s, or antibodies and their antigen s.

6. Agar-gel reaction
The reaction between an antibody and an antigen during an immunology lab procedure where the two are allowed to diffuse toward each other through an agar-gel medium. Lines of precipitation form in the places on the gel where the two react with each other and shows where the reaction has occurred.

7. Allergens
antigens that provoke an allergic reaction.

8. Allergy
A harmful immune reaction, either immediate-type or delayed-type hypersensitivity caused by a foreign antigen (i.e. allergen ) in food, pollen, or chemicals. In most cases the cause of the allergy is otherwise harmless to the body.

9. Alloimmune
Indicates or refers to an organism's being immune to protein s, cells, or other antigen s from members of its own species .

10. Alloimmunization
Immunization against allogenic antigen s; immunization against substances that can provoke an immune system response which are produced by genetically dissimilar members of the same species .

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