Immunological detection techniques commonly used in clinical practice include two types: first, tests related to antigen-antibody reactions, mainly immunohistochemistry. Immunohistochemistry is the application of labeled specific antibodies to localize and characterize antigens in cells by antigen-antibody reactions and chromogenic reactions of enzyme substrates in tissue cells in situ, and is the more commonly used detection method. In addition, there is immunofluorescence, hemagglutination inhibition, and radioimmunoassay, radioimmunoassay techniques are commonly used for the detection of trace substances such as hormones. Second, the detection of immune cells, immune cell detection in cytotoxicity test is more commonly used, cytotoxicity test is commonly used in the study of immune transplantation of tumors, rejection and viral infections. In addition, FCM flow cytometry can perform cell sorting, cell cycle and apoptosis analysis, mainly according to the needs of clinicians to do the corresponding examination.