Use of the APAAP method in the classification and diagnosis of hematologic disorders.

The APAAP technique is a sensitive and relatively easy immunocytochemical method to perform. It requires only a modest amount of laboratory space and no expensive equipment with the exception of a light microscope. Staining can be performed on peripheral blood and bone marrow films as well as cryostat and paraffin-embedded tissue sections. Prior to staining peripheral blood and bone marrow films as well as cryostat sections, slides can be stored at -70 degrees C, thus allowing for batch processing of specimens. Stained slides can be kept at room temperature for prolonged periods of time without loss of label. Surface or cytoplasmic determinants can be stained with the APAAP method. Because the preparations are usually counterstained, the identification of the labeled cells can be observed and photographed. The APAAP method is a reliable procedure and a significant addition to the routine hematology and histopathology laboratory.