Daudi cell stroma: An alternative to dithiothreitol to resolve daratumumab interference in pretransfusion testing

Abstract

Background Treatment of red blood cells with dithiothreitol (DTT) or trypsin effectively denatures CD38; however, this treatment damages other antigens, some of which are of clinical importance. Thus, other avenues to deplete daratumumab (DARA) from plasma samples should be explored. Study Design and Methods The Daudi B‐cell line was found to express high levels of CD38 and was sonicated in a sonication buffer to achieve complete cell lysis. The resulting stroma preparation was centrifuged at 20 000g for 20 minutes and then mixed with 250 μL of DARA–plasma and incubated for 10 minutes at 37°C. The stroma–DARA–plasma mixture was centrifuged again, and the supernatant was collected and subjected to four additional rounds of adsorption with fresh stroma. DARA‐depleted plasma was tested by gel indirect antiglobulin test (IAT). Results CD38 expression on Daudi cells was confirmed by flow cytometry. Gel IAT analysis showed that the incubation of plasma from DARA‐treated patients with Daudi cells stroma resulted in a significant depletion of DARA but allowing detection of other alloantibodies of interest such as anti‐K, anti‐Yta, and anti‐Gya. Conclusions Daudi cell stroma is inexpensive, easy to prepare in large batches, and can be used as an off‐the‐shelf reagent. Incubation of plasma from DARA‐treated patients with Daudi cell stroma can efficiently overcome DARA interference in serologic testing without affecting DTT‐ or trypsin‐sensitive antigens.

Overcoming Drug Interference in Transfusion Testing: A Spotlight on Daratumumab

“…Another method for overcoming daratumumab interference is the use of Daudi cell stroma generated by sonication. 40 Daudi B-cell stroma expresses high levels of CD38. Adsorbing a sample of plasma with Daudi cell stroma led to removal of daratumumab interference while allowing detection of alloantibodies such as anti-K, anti-Yta, and anti-Gya.…”

Efficient neutralization of daratumumab in pretransfusion samples using a novel recombinant monoclonal anti‐idiotype antibody

“…Lower concentrations of DTT (e.g., 0.01 M, as in the Osaka method 8,9 ) can be used to preserve K antigen expression. 10 Other approaches to mitigate the anti-CD38 interference include: denaturing RBC CD38 with other thiol reagents 11 or trypsin; 3,12 using phenotyped cord blood cells 13 or In(Lu) cells, 14 which express low or no serologically detectable CD38; blocking RBC CD38 using F(ab') 2 fragments 15 or antihuman globulin 16 ; using the manual polybrene method; 17 adsorbing plasma with Daudi cell stroma 18 or MEL-745A cells engineered to express high levels of CD38; 19 or providing phenotypically or genotypically matched RBC units. 11,20 One of the first approaches to resolve the anti-CD38 interference was to neutralize DARA in plasma with soluble CD38 or anti-DARA idiotype antibodies.…”