20.500.12556/DiRROS-30469 The influence of cytotoxic drugs on the immunophenotype of blast cells in paediatric B precursor acute lymphoblastic leukaemia Vpliv citotoksičnih zdravil na imunofenotip blastnih celic B-celične akutne limfoblastne levkemije otrok Flow cytometry plays is important in the diagnosis of acute lymphoblastic leukaemia (ALL) and when antigen-specific immunotherapy is indicated. We have investigated the effects of prednisolone, vincristine, daunorubicin, asparaginase and methotrexate on the antigen expression on blast cells that could influence the planning of antigen-specific therapy as well as risk-based treatment assignment. Patients and methods. Patients aged ≤ 17 years with de novo B-cell ALL (B-ALL) were enrolled in the study. Blast cells were isolated and exposed in vitro to 5 individual cytotoxic drugs in logarithmically increasing concentrations. Then, the expression of CD10, CD19, CD20, CD27, CD34, CD45, CD58, CD66c and CD137 antigens was determined by quantitative flow cytometry. Results. Cytotoxic drugs caused dose-dependent or dose-independent modulation of antigen expression. Daunorubicin caused a dose-dependent down-modulation of CD10, CD19, CD34, CD45 and CD58 and an up-modulation of CD137. Vincristine caused a dose-dependent down-modulation of CD19 and CD58 and an up-modulation of CD45. Daunorubicin also caused dose-independent down-modulation of CD27 and prednisolone down-modulation of CD10, CD19, CD27, CD34 and CD58. Down-modulation of CD20 was detected only in relation to the specific dose of daunorubicin. Conclusions. The results of the study have shown that cytotoxic drugs can alter the expression of antigens that are important for immunotherapy. Importantly, daunorubicin, prednisolone and vincristine caused down-modulation of CD19 and CD58, suggesting that these drugs are better avoided during bridging therapy prior to bispecific antibodies or CAR-T cell therapy. In addition, immunophenotypic changes on blast cells induced by different drugs could also influence risk-based treatment assignment. immunophenotypic changes chemotherapy immunotherapy imunofenotipi spremmembe kemoterapija imunoterapija true false true Onkološki inštitut Ljubljana Angleški jezik Slovenski jezik Neznano 2026-06-26 14:03:14 2026-06-26 14:03:15 2026-06-27 03:52:15 0000-00-00 00:00:00 2024 0 0 str. 133-144, XIII no. 1 Vol. 58 Mar. 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2024-03-01 616-006 1318-2099 10.2478/raon-2024-0006 187712771 RAZ_Prelog_Tomaz_2024.pdf RAZ_Prelog_Tomaz_2024.pdf 1 789C826D0243E75FDB45451D5671B5FF 0c51be78119c140cee87ba6a7203f71f45b3830a60be682b5e5728f39f632e4e 1ce28f8c-7157-11f1-b414-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=46274 Društvo radiologije in onkologije Onkološki inštitut Ljubljana 0 0 0