Allogeneic Blood Stem Cell Transplantation: Peripheralization and Yield of Donor-Derived Primitive Hematopoietic Progenitor Cells (CD34+ Thy-ldim) and Lymphoid Subsets, and Possible Predictors of Engraftment and Graft-Versus-Host Disease

Apheresis-derived hematopoietic progenitor cells have recently been used for allogeneic transplantation. Forty-one normal donors were studied to assess the effects of recombinant human granulocyte colony-stimulating factor (rhGCSF) (12 pglkgld) on the peripheralization of hematopoietic progenitor cells and lymphoid subsets. The white blood cell, polymorphonuclear cell (PMNC), and lymphocyte concentrations at the peak of rhG-CSF effect in the donor's peripheral blood (PB) exceeded baseline by 6.4-, 8.0-, and 2.2-fold, respectively. Corresponding concentrations of PB CD34' cells and primitive subsets such as CD34' Thy-ldim, and CD34' Thy-l""' CD38cells increased by 16.3-fold, 24.2-fold, and 23.2-fold. respectively in eight normal donors. The percentage of CD34+ Thy-ldim and CD34+ Thy-ldim CD38cellsamong CD34+ cells increased as well, suggesting an additional peripheralization effect of rhG-CSF on primitive CD34'subsets. The preapheresis PB CD34' and CD34' Thy-ldim cell concentrations were predictive of their corresponding apheresis yield per liter of donor blood processed. PB lymphoid subsets were not significantly affected by rhG-CSF treatment. The mean apheresis-derived yield of CD34+, CD34+ Thy-ldi", and CD34' Thy-ldim CD38cells per kilogram of recipient body weight and per liter of donor blood processed was 48.9 x I O 4 (n = 41). 27.2 x IO4 (n = IO), and 1.9 x I O 4 (n = IO), respectively. As compared with 43 single bone marrow (BM) harvests, the CD34' cell yield of peripheral blood progenitor cell allografts of 41 normal donors exceeded that of BM allo-