title: Immune Recovery after Allogeneic Hematopoietic Stem Cell Transplantation Following Flu-TBI versus TLI-ATG Conditioning.
abstract: OBJECTIVE
  A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been developed to induce graft-versus-tumor effects without graft-versus-host disease (GVHD).
  
  
  METHODS
  We compared immune recovery in 53 patients included in a phase II randomized study comparing nonmyeloablative HCT following either fludarabine plus 2 Gy total body irradiation (TBI arm, n = 28) or 8 Gy TLI plus ATG (TLI arm, n = 25).
  
  
  RESULTS
  In comparison with TBI patients, TLI patients had a similarly low 6-month incidence of grade II-IV acute GVHD, a lower incidence of moderate/severe chronic GVHD (P = 0.02), a higher incidence of CMV reactivation (P < 0.001), and a higher incidence of relapse (P = 0.01). While recovery of total CD8(+) T cells was similar in the two groups, with median CD8(+) T-cell counts reaching the normal values 40 to 60 days after allo-HCT, TLI patients had lower percentages of naïve CD8 T cells. Median CD4(+) T-cell counts did not reach the lower limit of normal values the first year after allo-HCT in the two groups. Furthermore, CD4(+) T-cell counts were significantly lower in TLI than in TBI patients the first 6 months after transplantation. Interestingly, while median absolute regulatory T-cell (Treg) counts were comparable in TBI and TLI patients, Treg/naïve CD4(+) T-cell ratios were significantly higher in TLI than in TBI patients the 2 first years after transplantation.
  
  
  CONCLUSIONS
  Immune recovery differs substantially between these two conditioning regimens, possibly explaining the different clinical outcomes observed (NCT00603954).
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium. m.hannon@chu.ulg.ac.be.
authors.forename: Muriel
authors.initials: M
authors.lastname: Hannon
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium. Department of Clinical Hematology, CHU of Liège, Liège, Belgium.
authors.forename: Yves
authors.initials: Y
authors.lastname: Beguin
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium.
authors.forename: Grégory
authors.initials: G
authors.lastname: Ehx
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium. Department of Clinical Hematology, CHU of Liège, Liège, Belgium.
authors.forename: Sophie
authors.initials: S
authors.lastname: Servais
authors.affiliation: Department of statistics, SIME, CHU of Liège, Liège, Belgium.
authors.forename: Laurence
authors.initials: L
authors.lastname: Seidel
authors.affiliation: Mont-Godine University Hospital (UCL), Yvoir, Belgium.
authors.forename: Carlos
authors.initials: C
authors.lastname: Graux
authors.affiliation: AZ Gasthuisberg Leuven, Leuven, Belgium.
authors.forename: Johan
authors.initials: J
authors.lastname: Maertens
authors.affiliation: Ghent University Hospital, Ghent, Belgium.
authors.forename: Tessa
authors.initials: T
authors.lastname: Kerre
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium.
authors.forename: Coline
authors.initials: C
authors.lastname: Daulne
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium.
authors.forename: Muriel
authors.initials: M
authors.lastname: de Bock
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium.
authors.forename: Marianne
authors.initials: M
authors.lastname: Fillet
authors.affiliation: Department of Clinical Hematology, CHU of Liège, Liège, Belgium.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Ory
authors.affiliation: Department of Clinical Hematology, CHU of Liège, Liège, Belgium.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Willems
authors.affiliation: Department of Laboratory Medicine, University of Liège, Liège, Belgium.
authors.forename: André
authors.initials: A
authors.lastname: Gothot
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Humblet-Baron
authors.affiliation: Groupe Interdisciplinaire de Génoprotéomique Appliquée (GIGA)-I3, University of Liège, Liège, Belgium. Department of Clinical Hematology, CHU of Liège, Liège, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Baron
mesh_terms: D000328:Adult; D000368:Aged; D000961:Antilymphocyte Serum / Q000008:administration & dosage; D000970:Antineoplastic Agents / Q000008:administration & dosage; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D005260:Female; D005434:Flow Cytometry; D006086:Graft vs Host Disease / Q000453:epidemiology; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011878:Radiotherapy / Q000379:methods; D019172:Transplantation Conditioning / Q000379:methods*; D014184:Transplantation, Homologous; D014740:Vidarabine / Q000008:administration & dosage / Q000031:analogs & derivatives
chemical_list: D000961:Antilymphocyte Serum; D000970:Antineoplastic Agents; D007155:Immunologic Factors; D014740:Vidarabine; C024352:fludarabine