We used flow cytometry to determine the CD58 expression on nonmalignant B cells at different stages of maturation in the bone marrow and compared it with that of blasts in adult and pediatric precursor B-cell acute lymphoblastic leukemia (B-ALL). The mean fluorescence intensity (MFI) of CD58 expression decreased significantly as nonmalignant B cells differentiated in the bone marrow from an early to a mature stage. Few nonneoplastic B cells at a mid or mature stage of development expressed CD58 MFI values comparable to those seen in leukemic cases. Early-stage nonneoplastic B-cell precursors expressed relatively higher CD58 levels, which frequently overlapped with the variable level of CD58 expression observed among leukemic blasts. As a group, however, the malignant precursor B-ALL cells showed significantly higher expression of CD58 than nonmalignant B-cell populations at any maturational stage. These findings support the potential usefulness of CD58 expression in the diagnosis and monitoring of precursor B-ALL, but only when blasts express high levels of CD58.

No abstract

In this report, the flow cytometric expression patterns for CD14 on monocytic cells and CD16 on granulocytic cells in peripheral blood or bone marrow specimens are illustratedfor 15 patients proven to have a paroxysmal nocturnal hemoglobinuria (PNH) phenotype by flow cytometric analysis for CD55 and CD59. The varied clinical manifestations of PNH and its rarity may make it difficult to recognize clinically. As a result, blood or bone marrow samples may be submitted for flow cytometric analysis to exclude bone marrow neoplasia or dysplasia in patients with cytopenias rather than to exclude PNH. This was true in 5 of 15 study cases. Unlike CD55 and CD59, CD14 and/or CD16 are assessed routinely in the flow cytometric analysis of blood and bone marrow samples. Recognition of abnormal patterns of CD14 and CD16 expression might permit the identification of clinically unsuspected PNH by routine flow cytometric analysis.

In this report, the flow cytometric expression patterns for CD14 on monocytic cells and CD16 on granulocytic cells in peripheral blood or bone marrow specimens are illustratedfor 15 patients proven to have a paroxysmal nocturnal hemoglobinuria (PNH) phenotype by flow cytometric analysis for CD55 and CD59. The varied clinical manifestations of PNH and its rarity may make it difficult to recognize clinically. As a result, blood or bone marrow samples may be submitted for flow cytometric analysis to exclude bone marrow neoplasia or dysplasia in patients with cytopenias rather than to exclude PNH. This was true in 5 of 15 study cases. Unlike CD55 and CD59, CD14 and/or CD16 are assessed routinely in the flow cytometric analysis of blood and bone marrow samples. Recognition of abnormal patterns of CD14 and CD16 expression might permit the identification of clinically unsuspected PNH by routine flow cytometric analysis.