Abstract
The diagnosis of haematopoietic disorders by immunological methods, termed 'immunophenotyping', or 'cell marker analysis', is now a routine investigation in many haematology laboratories. A wide range of antibodies and fluorochromes are commercially available, in addition to antigen detection systems: immunocytochemistry, direct or indirect immunofluorescence, incorporating either light microscopy or flow cytometry. In view of this variety in methodology, it is important that all antibodies are used appropriately. The following review highlights a variety of issues, including antibody selection and dilution, negative controls, storage, fixatives as well as quality control, that require consideration prior to the routine use of antibody reagents.