The expression of SLAMF7 levels in malignant B cells: a novel therapeutic pathway for patients with CLL

Abstract

Signalling lymphocyte activation molecule (SLAM) F7 is found on the surface of some immune cells including B-lymphocytes. Its activation leads to the proliferation or differentiation of immune cells. The objectives of the study were to measure SLAMF7 expression levels on B-CLL cells, and to upregulate the expression of SLAMF7 with phorbol myristate acetate (PMA) and Bryostatin. The levels of expression of SLAMF7 receptors of B-CLL cells from patients were measured; using immunofluorescence, flow cytometry, confocal microscopy and reverse transcriptase polymerase chain reaction (RT-PCR). The effects of treatments with PMA and Bryostatin were determined from different patients. Different levels of SLAMF7 expression were found to be associated with B-CLL cells from different patients. PMA treatment of B-CLL cells showed more positive SLAMF7 staining with the majority of the extracted B-CLL cell cases, while less positive results were associated with Bryostatin treatment. The study has shown that both PMA and Bryostatin could upregulate SLAMF7. Successful modulation of SLAMF7 expression may provide a novel target for the treatment of patients with CLL.