Clinical application of a novel CD45-negative cell sorting in cytogenetic detection of multiple myeloma

Abstract

Objective To explore the clinical value of a novel CD45-negative cell sorting technology in sorting and enriching tumor plasma cells in multiple myeloma (MM). Methods A total of 60 newly diagnosed MM patients from 3 hospitals in Chongqing from July 2018 to December 2019 were recruited in this study. Bone marrow samples of 3~4 mL were taken from each patient and divided into 2 parts. One part (direct detection group) was directly detected by flow cytometry and FISH, and the other part (CD45 sorting group) was subjected to the novel CD45-negative cell sorting, followed by flow cytometry and FISH. The proportion of plasma cells in bone marrow, detection rate of cytogenetic abnormalities and risk stratification were compared in every patient before and after sorting. Results The proportion of plasma cells in bone marrow samples was (14.5±13.8)% and (51.5±30.3)%, respectively, in the direct detection group and CD45 sorting group, with that of the latter group 7.69 times higher than that of the former group (P＜0.001). Direct FISH indicated 17 cases of cytogenetic abnormality, while FISH after CD45 sorting found 39 patients having cytogenetic abnormalities (P＜0.001). The positive rates of IgH rearrangement, 13q14 deletion, 1q21 amplification and 17p deletion were all increased significantly after sorting. According to mSMRAT3.0 standard, only 28.3% of the patients were identified at high risk before sorting, but the number was increased significantly after sorting (accounting for 53.3%, P=0.002). Conclusion The new CD45 negative cell sorting technology is simple and easy to operate, and can improve the detection rate of cytogenetic abnormalities and accurately carry out risk stratification for guiding treatment in MM patients. Thus, this technology is worthy of promotion in primary hospitals.

Keywords

• cd45-negative cell sorting
• multiple myeloma
• cytogenetic abnormality