title: Generation of memory T cells for adoptive transfer using clinical-grade anti-CD62L magnetic beads.
abstract: Pre-clinical studies of allogeneic stem cell transplantation suggest that depletion of naive T cells from donor lymphocytes will reduce the risk of GvHD but preserve immunity to infectious pathogens. In this study, we have established a clinical-grade protocol under good manufacturing practice conditions for purging CD62L(+) naive T cells from steady-state leukapheresis products using the CliniMACS system. The efficacy of immunomagnetic CD62L depletion was assessed by analysis of cell composition and functional immune responses. A median 2.9 log CD62L depletion was achieved with no evidence of CD62L shedding during the procedure and a mean T-cell yield of 47%. CD62L(-) cells comprised an equal mix of CD4(+) and CD8(+) T cells, with elimination of B cells but maintenance of regulatory T cells and natural killer cell populations. CD62L-depleted T cells were predominantly CD45RA(-) and CD45RA(+) effector memory (>90%) and contained the bulk of pentamer-staining antivirus-specific T cells. Functional assessment of CD62L(-) cells revealed the maintenance of antiviral T-cell reactivity and a reduction in the alloreactive immune response compared with unmanipulated cells. Clinical-grade depletion of naive T cells using immunomagnetic CD62L beads from steady-state leukapheresis products is highly efficient and generates cells suitable for adoptive transfer in the context of clinical trials.
authors.affiliation: Transplantation Immunology Group, Institute of Cancer Studies, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Verfuerth
authors.affiliation: Transplantation Immunology Group, Institute of Cancer Studies, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: P S E
authors.initials: PS
authors.lastname: Sousa
authors.affiliation: Oncohematology Research Group, Navarrabiomed-Miguel Servet Foundation, Pamplona, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Beloki
authors.affiliation: The Centre for Cell, Gene and Tissue Therapeutics, Institute of Immunity and Transplantation, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: M
authors.identifier: http://orcid.org/0000-0002-0379-7161
authors.initials: M
authors.lastname: Murray
authors.affiliation: The Centre for Cell, Gene and Tissue Therapeutics, Institute of Immunity and Transplantation, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: M D
authors.initials: MD
authors.lastname: Peters
authors.forename: A T
authors.initials: AT
authors.lastname: O'Neill
authors.affiliation: Department of Haematology, Royal Free London NHS Foundation Trust, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Mackinnon
authors.affiliation: The Centre for Cell, Gene and Tissue Therapeutics, Institute of Immunity and Transplantation, University College London Medical School, Royal Free Campus, London, UK.|Department of Haematology, Royal Free London NHS Foundation Trust, London, UK.
authors.forename: M W
authors.initials: MW
authors.lastname: Lowdell
authors.affiliation: Transplantation Immunology Group, Institute of Cancer Studies, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: R
authors.initials: R
authors.lastname: Chakraverty
authors.affiliation: The Centre for Cell, Gene and Tissue Therapeutics, Institute of Immunity and Transplantation, University College London Medical School, Royal Free Campus, London, UK.
authors.forename: E R
authors.initials: ER
authors.lastname: Samuel
mesh_terms: D019264:Adoptive Transfer / Q000379:methods*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D064368:Healthy Volunteers; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*; D018189:Immunomagnetic Separation / Q000379:methods*