In immunology, the term sensitization is used for the following concepts:Immunization by inducing an adaptive response in the immune system. In this sense, sensitization is the term more often in usage for induction of allergic responses. To bind antibodies to cells such as erythrocytes in advance of performing an immunological test such as a complement-fixation test or a Coombs test. The antibodies are bound to the cells in their Fab regions in the preparation. To bind antibodies or soluble antigens chemically or by adsorption to appropriate biological entities such as erythrocytes or particles made of gelatin or latex for passive aggregation tests.