Abstract: Objective To investigate the expression of CD38 on erythrocyte surface of ABO with different blood groups and different preservation periods, in order to clarify the blood selection problem of daretuzumab in m ultiple myeloma (MM) patients. Methods Donor blood samples collected from the Blood Collection and Supply Centers of the Whole Army from May 25, 2022 to June 30, 2022 were selected. The four blood groups of type A, B, O and AB were divided into 5 preservation cycles from the date of blood collection. There were 15 normal specimens in different preservation periods of the four blood groups, totaling 300 specimens. For each preservation cycle, 5 people with different blood types were randomly mixed into a group and divided into three groups of specimens. The concentration gradient of CD38 monoclonal antibody was determined by diluting 100 mg/5 mL of CD38 monoclonal antibody with normal saline. Standard pre-transfusion tests were used for detection. Red blood cells and different levels of CD38 antibodies were added to anti-human globulin card in proportion (50 μL for red blood cells and 25 μL for CD38 antibodies), incubated for 15 min, and centrifuged for 10 min to observe the results. Results The monoanticoagulant strength of red blood cells was consistent with that of CD38 for blood groups A, B, O and AB, and there was no statistical significance (P>0.05). The concentration of CD38 monoclonal antibody of the four blood groups ranged from 200 μg to 256 μg, and the red blood cells of different preservation periods all showed 2+ agglutination, with no statistical significance (P=0.062). When the concentration of CD38 mab was 128 ng and 64 ng, erythrocyte agglutination was weakened in five preservation cycles, and the difference was statistically significant (P<0.05). Conclusion The expression of CD38 in different ABO blood groups is basically the same without significant difference. Red blood cells with different storage periods will not increase hemolysis in patients with m ultiple myeloma.

Key words: CD38 monoclonal antibody, ABO different blood types, Multiple myeloma, Erythrocyte retention period