sensitization
1. (of a cell) The alteration of the integrity of a plasma membrane resulting from the reaction of specific antibodies with antigens on the surface of the cell. In the presence of complement, the cell ruptures.

2. (of an individual) Initial exposure to a specific antigen such that re-exposure to the same antigen causes a severe immune response (see anaphylaxis).

sensitization
1. The increase in the likelihood that a particular and significant stimulus will produce a response in an animal repeatedly exposed to it. Compare EXTINCTION; HABITUATION.

2. In increase in the specific reactivity of an organism or cell to an antigen or hapten.

sensitization (sen-si-ty-zay-shŏn) n.
1. alteration of the responsiveness of the body to the presence of foreign substances. In the development of an allergy, an individual becomes sensitized to a particular allergen. The phenomena of sensitization are due to the production of antibodies.

2. (in behaviour therapy) a form of aversion therapy in which anxiety-producing stimuli are associated with the unwanted behaviour.

sensitization The increase in the likelihood that a particular and significant stimulus will produce a response in an animal repeatedly exposed to it. Compare extinction and habituation.