A large-scale method for T cell depletion: towards graft engineering of mobilized peripheral blood stem cells.
We have investigated the feasibility and efficacy of large-scale T cell depletion from granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cells (PBSC). The method is based on the use of a CD3 antibody conjugated to magnetic microbeads and magnetic activated cell sorting (Clinimacs). A total of eight large-scale experiments were performed. In four experiments, CD3(+) T cells were depleted from PBSC obtained from volunteers mobilized with G-CSF whereas, in four experiments, T cells were depleted from PBSC from stem cell donors, in which the CD34(+) stem cells had been removed for allogeneic transplantation by positive selection prior to T cell depletion. The mean number of processed mononuclear cells (MNCs) was 3.3 x 10(10) (range 1.5 x 10(10)-5.1 x 10(10)) with a mean T cell proportion of 35.8% (range 16.7-64.0%). After T cell depletion, the percentage of contaminating T cells was 0.15% (range 0.01-1.01%) with a mean log(10) depletion of 3.4 (range 2.8-4.1). The mean recovery of CD3-negative MNCs after depletion was 76% (range 52-100%). The mean recovery of CD34(+) stem cells in the four evaluable experiments was 82% (range 75-92%). In vitro colony assays and in vivo NOD/SCID repopulation assays showed that this large-scale T cell depletion method has no negative impact on the function of the hematopoietic precursor cells. Therefore, we conclude that this T cell depletion method is a valuable tool for further graft engineering strategies involving mobilized PBSCs.
Division of Stem Cell Transplantation, St Jude Children's Research Hospital, 332 N Lauderdale St., Memphis, TN 38105, USA.
P R
PR
Gordon
T
T
Leimig
I
I
Mueller
A
A
Babarin-Dorner
M A
MA
Holladay
J
J
Houston
G
G
Kerst
T
T
Geiger
R
R
Handgretinger
D000071916:AC133 Antigen; D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000032:analysis; D017252:CD3 Complex / Q000276:immunology; D002469:Cell Separation / Q000379:methods*; D005240:Feasibility Studies; D006023:Glycoproteins / Q000276:immunology; D006085:Graft Survival; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D018189:Immunomagnetic Separation; D007963:Leukocytes, Mononuclear / Q000166:cytology; D051379:Mice; D016688:Mice, Inbred NOD; D016853:Muromonab-CD3; D010455:Peptides / Q000276:immunology; D036102:Peripheral Blood Stem Cell Transplantation / Q000379:methods; D013601:T-Lymphocytes; D014183:Transplantation, Heterologous
D000071916:AC133 Antigen; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018952:Antigens, CD34; D017252:CD3 Complex; D006023:Glycoproteins; D016853:Muromonab-CD3; D010455:Peptides; D016179:Granulocyte Colony-Stimulating Factor