Cytotoxicity Assessment and Apoptosis-related Gene Profiling of Antibody Treated Acute Myeloid Leukemia (AML) and Acute Lymphocytic Leukemia (ALL) Cancerous Cell Lines

Acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) are common acute leukemia in adults and children, respectively. In these malignancies, chemotherapy is the main treatment strategy that fails in many cases and is usually associated with adverse effects on healthy cells. In this regard, the development of new therapies is essential. Monoclonal antibodies directed to the cell surface markers of leukemic blasts may have promising consequences with minimal toxic effects on normal cells. Since cluster of differentiation 45Ra (CD45Ra) and CD123 antigens, two considered surface markers of leukemic blasts in AML and ALL respectively, are overexpressed on AML and ALL blasts, CD34+ leukemic progenitors, and AML-LSCs in comparison with normal hematopoietic stem cells (HSCs), they were selected to be targeted; using specific monoclonal antibodies. In this project, CD45Ra+ cells and CD123+ cells were targeted by anti-CD45Ra and/or anti-CD123 monoclonal antibodies. Cytotoxicity effect and cell death induction was determined by 3-(4,5-dimethylthiazol-2-yl)-2–5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Changes in the expression profile of MCL1, cMyc, Survivin, Id1, and PIM1 genes were assessed by real-time PCR. Statistical analysis of the results showed effective antibody-mediated cytotoxicity and induction of apoptosis in KG1α (CD45Ra+) and Nalm6 (CD123+) cell lines. Also, a significant change in the expression level of some of the apoptosis-related genes was observed. According to the results of this study, it can be concluded that an effective targeting of AML and ALL cancerous cell lines can be performed by anti-CD45Ra and anti-CD123 monoclonal antibodies through their effector functions and apoptosis induction.