RecruitingPhase 2Device studyAlpha/Beta T Cell and CD19+ B Cell Depletion in Allogeneic Stem Cell Transplantation in Patients With Malignant DiseasesThis study will assess the safety, efficacy, and feasibility of ⍺/β CD3+ T-cell and CD19+ B-cell depletion in allogeneic stem cell transplantation in patients with acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), juvenile myelomonocytic leukemia (JMML), high risk myelodysplastic syndrome (MDS), chronic myeloid leukemia (CML) and lymphoma. Subjects will receive an allogeneic stem cell transplant that has been depleted of ⍺/β CD3+ T-cells and CD19+ B-cells using the Miltenyi CliniMACS Prodigy® system.