Abstract
To elucidate the influence of various storage conditions on cell viability and flow cytometric (FCM) detection of cell surface antigens, bone marrow aspirates obtained from 8 patients with acute lymphoblastic leukemia were divided into aliquots with or without culture medium, and stored at 4°C or 20°C for 12, 24, and 48 h. Mononuclear cells were isolated from aliquots either immediately after bone marrow collection or after storage under various conditions. There were no significant differences between fresh and stored cells in cell viability assessed with trypan blue stain, or in FCM detection of cell surface antigens including CD10, CD19, CD20, CD34, CD38, CD45 and CD58. However, CD22 levels that were positive in 2 patients became negative under all storage conditions. These results indicate that FCM with CD22 antibody may affect an evaluation of neoplastic B cell differentiation when samples are not processed immediately after collection.
