Abstract:Abstract: Objective To analyze the antibodies in the multiple myeloma patients treated with anti-CD38 MoAb antibodies and explore the strategies for identification of antibodies. Methods A total of 30 patients with multiple myeloma who were treated with anti-CD38 MoAb and exhibited crossmatching incompatibility from November 2019 to June 2021 were selected as the study subjects. 0.2 mol/L dithiothreitol ( DTT) -treated profiling cells were used to identify the specificity of various antibodies in the studied serum samples. The serum of the patients with autoantibodies were identified by multiple dilution method. The concentrations of free hemoglobin in normal saline and diluent for blood group analysis were monitored on the day 1, 7, 14, 28 and 35. Results The identification for profiling cells treated with DTT revealed that none was detected as positive antibodies in the 24 cases. Anti-E alloantibodies combined with autoanti- bodies were detectable in 1 case. Autoantibodies were detectable in 5 cases who were conformed by diluted serum. Among them, 4 cases showed no andibody-related specificity, and one mimicked the specifcity of anti-C antibody. The concentrations of free hemoglobin in both saline group and diluent group showed increased trend with the prolongation of storage time, but the difference between the two groups showed statistically significant. Conclusion DTT-treated spectrum cells combined with serum dilution method can be used to identify the alloantibodies ,autoantibodies quickly and easily in the multiple myeloma patients who were treated with anti-CD38 MoAb.The diluents for blood group analysis can be used to preserve the DTT- treated spectrum cells.