Definition |
A method that uses the reaction of antibodies with cell antigens to determine a specific type of cell in a sample of blood cells, marrow cells, or lymph node cells. The antibodies react with specific antigens on the cell. A tag is attached to antibody so that it can be detected. The tag can be identified by the laboratory equipment used for the test. As cells carrying their array of antigens are tagged with specific antibodies they can be identified; for example, myelogenous leukemic cells can be distinguished from lymphocytic leukemic cells. Normal lymphocytes may be distinguished from leukemic lymphocytes. This method also helps to subclassify cell types, which may, in turn, help to decide on the best treatment to apply in that type of leukemia or lymphoma. The antigen on a cell is referred to as cluster of differentiation or "CD" with an associated number. For example, CD16 may be present on leukemic lymphoblasts and CD33 on leukemic myeloblasts. determining what kind of surface molecules are present on leukemic lymphoblasts. Used by pathologists to determine the exact sub-type of leukemia. Immunophenotyping is the classification of cell types according to their immunologic characteristics. With the development of a form of testing known as monoclonal antibody (MAb) technology, types of leukemia cell lines are now better defined. Numerous antibody reagants have been identified; reagents are substances used to create chemical reactions. Some reagants recognize specific "clusters of differentiation" (CD); for example, CD79 recognizes B-cells, CD3 recognizes T-cells, and antimyeloperoxidase recognizes myeloid cells. Other useful, but less specific reagants are CD19, CD22,CD5, CD7, CD13, CD33, glycophorin, and CD61.
|