Introduction
Allogeneic hematopoietic stem cell transplantation (HSCT) provides a
potentially curative treatment for both malignant and non-malignant
hematopoietic diseases in pediatric and adult age
groups.1 While bone marrow (BM) has been the most
common source of both autologous and allogeneic hematopoietic stem cells
for many years, peripheral blood stem cells (PBSC) mobilized by the
growth factor, granulocyte colony stimulating factor (G-CSF) have become
a more important source for hematopoietic stem cells in recent years.
Early clinical studies on the source of stem cells showed that PBSC
provided a higher dose of stem cells as well as faster engraftment
benefit compared to BM without G-CSF modification.2Post-transplantation engraftment is directly related to the source of
hematopoietic stem cells and the number of immature progenitor cells in
the graft.3
Despite being the recently preferred source of stem cells for most
adults with a transplant from an HLA-matched sibling donor, PBSC appears
to be less commonly preferred as a standard stem cell source for
pediatric patients. A recent analysis conducted by the International
Bone Marrow Transplant Registry (IBMTR) showed that the use of PBSC in
pediatric patients had a higher risk of chronic graft versus host
disease (GvHD) and transplantation-related mortality. In addition,
apheresis often requires insertion of a central venous catheter, which
challenges the feasibility in children. 2 On the other
hand, PBSC has recently been the preferred source for allogeneic HSCT in
adults, especially in those with malignant disease.2,3,4 As a result of BMSC being more widely preferred
as a stem cell source for allogeneic HSCT during childhood, acute and
chronic GvHD, which are among the most important problems increasing
transplant-related mortality (TRM), are less common compared to
adults.5
While G-CSF administration to autologous transplant donors in order to
collect PBSC for autologous transplantation is now routinely used,
recently, it has also been frequently used in normal healthy donors for
allogeneic transplantation.1 Results from studies on
different donor-derived stem cells in allogeneic HSCT have shown that
higher doses of BM nucleated cell doses given to HSCT recipients result
in faster engraftment and improved survival.6
It has been shown in numerous studies that the collection of CD34 cells
from PBSC and BMSC after administering growth factors such as G-CSF to
donors, accelerates engraftment with the quantitative and qualitative
effects of growth factors on progenitor cells and increases the number
of nucleated and CD34 cells for harvesting.7 When
G-CSF is used to collect stem cells from a healthy donor whose stem cell
source is BM, the number of nucleated and CD34 cells collected in the BM
product increases and faster engraftment occurs without increasing the
risk of GvHD. 7,8
The present study reports the results we obtained by administering a
single dose of 3 different G-CSF molecules to healthy donors before
collecting CD34 cells from BM.