Simplifying Stem Cell Harvesting

Restoring hematological function in patients after myeloablative chemotherapy is increasingly achieved using peripheral blood-derived progenitor cells rather than autologous bone marrow transplantation, as this approach greatly shortens the duration of pancytopenia and so reduces the risks of infection and bleeding.

Now, researchers from Germany have reported that this approach, which still requires the removal of a large volume of blood by leukapheresis, can be improved by growing the progenitor cell populations ex vivo after taking a relatively small volume of blood. Patients who received high-dose chemotherapy for solid tumors had their hematopoietic systems stimulated prior to harvesting by treatment with Amgen's Neupogen (filgrastim; G-CSF), and the CD34+ progenitor cells were separated from peripheral blood samples using the Ceprate SC column developed by CellPro.

The progenitor cells were grown in medium containing autologous plasma, recombinant human stem cell factor, interleukin-1 beta, IL-3, IL-6 and erythropoietin, and then reinfused back into the patient to allow recovery of the hematological system. The cells promoted a rapid and sustained recovery, according to the researchers, who point out that this approach requires a smaller amount of patient blood so reduces the risk of tumor cell contamination, circumvents the need for leukapheresis and may allow more intensive high-dose chemotherapy to be carried out.