title: Clinical scale isolation of T cell-depleted CD56+ donor lymphocytes in children.
abstract: We present a clinical scale method for immunomagnetic separation of CD56+ donor natural killer cells for adoptive immunotherapy of pediatric leukemias after allogeneic transplantation. This time-saving and partially automated procedure employed CD56+ selection followed by CD3+ depletion, resulting in a median purity of 98.6% NK cells and a four-log depletion of T cells. The enriched NK cells demonstrated high cytotoxic activity against K562 target cells and fresh leukemic blasts with low HLA class I expression, which could be further enhanced by IL-2 stimulation. Lysis of NK-insensitive leukemic cells with high HLA class I expression could also be demonstrated via ADCC. Due to the high degree of T cell depletion, alloreactive proliferation in mixed lymphocyte cultures and response to T cell-specific mitogen stimulation was profoundly decreased. Our results suggest that, even in the case of mismatched donors, infusions of donor NK cells with extremely low T cell content may be a promising treatment option for leukemic minimal residual disease after allogeneic transplantation without risk of inducing severe GVHD.
authors.affiliation: Children's University Hospital, University of Tuebingen, Hoppe-Seyler Strasse 1, 72076 Tuebingen, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Lang
authors.forename: M
authors.initials: M
authors.lastname: Pfeiffer
authors.forename: R
authors.initials: R
authors.lastname: Handgretinger
authors.forename: M
authors.initials: M
authors.lastname: Schumm
authors.forename: B
authors.initials: B
authors.lastname: Demirdelen
authors.forename: S
authors.initials: S
authors.lastname: Stanojevic
authors.forename: Th
authors.initials: T
authors.lastname: Klingebiel
authors.forename: U
authors.initials: U
authors.lastname: Köhl
authors.forename: S
authors.initials: S
authors.lastname: Kuci
authors.forename: D
authors.initials: D
authors.lastname: Niethammer
mesh_terms: D019002:CD56 Antigen / Q000096:biosynthesis*; D002648:Child; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods; D016219:Immunotherapy, Adoptive; D007694:Killer Cells, Natural / Q000378:metabolism; D007937:Leukapheresis / Q000379:methods; D008213:Lymphocyte Activation / Q000276:immunology; D007959:Lymphocyte Culture Test, Mixed; D008212:Lymphocyte Depletion / Q000379:methods; D008934:Mitogens / Q000494:pharmacology; D016176:T-Lymphocyte Subsets / Q000378:metabolism* / Q000637:transplantation; D013601:T-Lymphocytes / Q000378:metabolism* / Q000637:transplantation; D014019:Tissue Donors; D014184:Transplantation, Homologous / Q000009:adverse effects
chemical_list: D019002:CD56 Antigen; D008934:Mitogens