title: Isolation and transplantation of autologous peripheral CD34+ progenitor cells highly purified by magnetic-activated cell sorting.
abstract: Peripheral stem cells were mobilized and collected in 26 pediatric patients with malignant diseases. A total of 47 leukaphereses were performed in the 26 patients. The mean number of nucleated cells collected was 4.5 +/- 2.6 x 10(8)/kg and the number of CD34+ progenitors collected was 6.7 +/- 6.8 x 10(6)/kg. CD34-positive selection was performed using a two-step method of magnetic-activated cell sorting (MACS) in 24 patients or a combination of an immunoaffinity column and MACS in two patients. The purity of the positively selected CD34+ progenitors was 98.8 +/- 0.7% and the number of isolated CD34+ cells was 6.5 +/- 5.9 x 10(6)/kg. Thus, the mean recovery of CD34+ cells was 93 +/- 10%. In 22 of the 26 patients, high-dose chemotherapy was performed with subsequent reinfusion of the highly purified CD34+ cells. In all 22 patients, a normal hematopoietic reconstitution was seen with a mean time of 12.4 +/- 2.7 days to reach >0.5 x 10(9)/l neutrophils (range 8-19 days). The time to reach independence from platelet transfusion was 31.6 +/- 17.0 days (range 16-78 days). There were no transplant-related deaths. In summary, we have shown that mobilized peripheral CD34+ progenitors can be highly purified with a good recovery, and that reinfusion of these cells after high-dose chemotherapy results in a rapid, complete and sustained engraftment. We conclude that this method can be used for purging in any CD34-negative malignancies and for autologous T and B cell depletion in the treatment of autoimmune diseases with high-dose immunoablative therapy.
authors.affiliation: Children's University Hospital, University of Tuebingen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Handgretinger
authors.forename: P
authors.initials: P
authors.lastname: Lang
authors.forename: M
authors.initials: M
authors.lastname: Schumm
authors.forename: G
authors.initials: G
authors.lastname: Taylor
authors.forename: S
authors.initials: S
authors.lastname: Neu
authors.forename: E
authors.initials: E
authors.lastname: Koscielnak
authors.forename: D
authors.initials: D
authors.lastname: Niethammer
authors.forename: T
authors.initials: T
authors.lastname: Klingebiel
mesh_terms: D000293:Adolescent; D018952:Antigens, CD34 / Q000032:analysis*; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D005434:Flow Cytometry; D006410:Hematopoiesis; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells; D006801:Humans; D018189:Immunomagnetic Separation; D007223:Infant
chemical_list: D018952:Antigens, CD34