CD-Chex TdT Plus is a ready-to-use control for evaluating intracellular and surface antigens including CD1a, CD2, CD4, CD5, CD7, CD8, CD34, cytoplasmic CD3 and nuclear TdT, with monoclonal antibody binding by flow cytometry. When the cells are stained with fluorescent antibodies and analyzed by flow cytometry, CD Chex TdT Plus provides reference values for abnormal peripheral blood leukocytes often found in certain types of hematopoietic neoplasms. It is a positive procedural control designed to monitor reagent staining, erythrocyte lysis, sample preparation and instrument performance. CD-Chex TdT Plus is compatible with BD Biosciences and Beckman Coulter flow cytometry systems.