Blood, 15 October 2001, Vol. 98, No. 8, pp. 2352-2357
CLINICAL OBSERVATIONS, INTERVENTIONS, AND THERAPEUTIC TRIALS
Allogeneic transplantation of CD34+
selected cells from peripheral blood from human leukocyte
antigen-identical siblings: detrimental effect of a high number of
donor CD34+ cells?
Alvaro Urbano-Ispizua,
Enric Carreras,
Pedro Marín,
Montserrat Rovira,
Carmen Martínez,
Francesc Fernández-Avilés,
Blanca Xicoy,
Juan-Carlos Hernández-Boluda, and
Emili Montserrat
From the Institute of Hematology and Oncology, Bone
Marrow Transplant Unit, Postgraduate School of Hematology
"Farreras-Valentí," Institut d'investigacions Biomediques
August Pi i Sunyer, Hospital Clínic of Barcelona, University of
Barcelona, Spain.
Clinical results after T-cell-depleted allografts might be
improved by modifying the graft content of progenitor and accessory cells. Although the association of the number of donor T cells with the
clinical outcome has been studied extensively, the optimum number of
progenitor cells that should be administered to patients is unknown.
The characteristics of 84 consecutive human leukocyte antigen
(HLA)-identical sibling transplants of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood progenitor cells depleted of
T cells by CD34+ positive selection
(allo-PBT/CD34+) were analyzed for their effect on clinical
outcome. After a median follow-up of 24 months (range, 1-70 months), 50 patients remain alive (59.5%) and 34 have died (21 [25%] as a
result of the transplant and 13 [15.5%] due to disease relapse). The
median number of CD34+ cells administered to the patients
was 3.9 × 106/kg (range, 1.2-14.3 × 106/kg). A number of CD34+ cells in the
inoculum of 1 × 106/kg to 3 × 106/kg was
associated with increased survival: 21 of 28 (75%) patients are alive,
as compared with 29 of 56 (52%) patients receiving more than
3 × 106/kg (actuarial probability 75% vs. 42%,
respectively; P = .01). In the multivariate analysis, the
independent prognostic variables for survival were CD34+
cell dose 1 × 106/kg to 3 × 106/kg
(RR = 4.8; P = .0008), sex-pairing match (RR = 3.2;
P = .002), and early stage of disease (RR = 2.8;
P = .007). From these results it appears that, in
allo-PBT/CD34+ from HLA-identical siblings, a number of
CD34+ cells in the inoculum between
1 × 106/kg to 3 × 106/kg is an important
factor for better survival, and that higher CD34+ cell
doses might be associated with a poorer outcome.
