Our previously published ex vivo expansion procedure starting from cord blood CD34+ cells enables a massive expansion of total and CD34+ cells and committed progenitors without negative impact on stem cells exhibiting both short- and long-term repopulating capacity.
It was upgraded to clinical scale [Macopharma HP01® medium in presence of SCF, FLT3-L (100 ng/ml each), G-SCF (10 ng/ml), and TPO (20 ng/ml)] and is in use for an ongoing clinical trial (adult allogeneic context), yielding encouraging results. In order to test the possibility
to use the expanded cells in distant transplantation centers, we studied the functional stability at +4°C (usual temperature of transportation) of hematopoietic progenitors and stem cells 48 h after expansion. If the cells were washed and resuspended in 4% albumin solution (actual procedure
for immediate injection), only one half of total nucleated and CD34+ cells and 30% of committed progenitors survived after 24 h. This condition has also an evident negative impact on stem cells in expansion product as demonstrated on the basis of reconstitution of NSG mice bone
marrow by human CD45, CD33, CD19+ cells as well as by human committed progenitors (CFU). Surprisingly, if the cells were stored 48 h at +4°C in culture medium, very good survival of total and CD34+ cells (90 to 100%) and colony forming unit cells (CFCs; around 70%)
was obtained, as well as the maintenance of stem cells (the same in vivo assay with NSG mice). These data point to the possibility of the maintenance of the full functional capacity of expanded grafts for 2 days, the time allowing for its transportation to any transplantation center worldwide.
Cell Transplantation publishes original, peer-reviewed research and review articles on the subject of cell transplantation and its application to human diseases. To ensure high-quality contributions from all areas of transplantation, separate section editors and editorial boards have been established. Articles deal with a wide range of topics including physiological, medical, preclinical, tissue engineering, and device-oriented aspects of transplantation of nervous system, endocrine, growth factor-secreting, bone marrow, epithelial, endothelial, and genetically engineered cells, among others. Basic clinical studies and immunological research papers are also featured. To provide complete coverage of this revolutionary field, Cell Transplantation will report on relevant technological advances, and ethical and regulatory considerations of cell transplants. Cell Transplantation is now an Open Access journal starting with volume 18 in 2009, and therefore there will be an inexpensive publication charge, which is dependent on the number of pages, in addition to the charge for color figures. This will allow work to be disseminated to a wider audience and also entitle the corresponding author to a free PDF, as well as prepublication of an unedited version of the manuscript.