title: Selection of normal human hematopoietic stem cells for bone marrow transplantation using immunomagnetic microspheres and CD34 antibody.
abstract: Complete yet nontoxic removal of tumor cells from autologous marrow grafts has proved difficult. New methods for separating normal stem cells from tumor cells are needed. The CD34+ cells in bone marrow, 1-2% of the low-density leukocytes, include precursors of all lymphohematopoietic lineages and probably also the primitive cells responsible for engraftment. A nontoxic, inexpensive, reproducible, and clinically applicable method for positive selection of CD34+ cells was developed. Paramagnetic microspheres coated with goat anti-mouse IgG1 are used to partition the cells; brief incubation with chymopapain is used to release them from the beads. Chymopapain exposure does not injury colony-forming cells or delay engraftment in rodents. Clinical volumes of bone marrow can be processed rapidly. In pilot experiments, the resulting grafts have a purity of 85-99% CD34+ cells and 40% median recovery of the assayable colony-forming cells. These studies form the background for a Phase I trial of autologous BMT using CD34+ stem cells.
authors.affiliation: Division of Pediatric Oncology, Johns Hopkins Oncology Center, Baltimore, Maryland.
authors.forename: L C
authors.initials: LC
authors.lastname: Strauss
authors.forename: T M
authors.initials: TM
authors.lastname: Trischmann
authors.forename: S D
authors.initials: SD
authors.lastname: Rowley
authors.forename: J M
authors.initials: JM
authors.lastname: Wiley
authors.forename: C I
authors.initials: CI
authors.lastname: Civin
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology*; D018952:Antigens, CD34; D016026:Bone Marrow Transplantation / Q000276:immunology*; D002469:Cell Separation / Q000379:methods*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D006801:Humans; D008280:Magnetics; D008863:Microspheres; D051381:Rats
chemical_list: D015703:Antigens, CD; D018952:Antigens, CD34