[G-CSF - primed bone marrow as a stem-cell source for allogeneic bone marrow transplantation in children].

Background: Cell dose is one of the most important factors contributing to transplant success. Collection of G-CSF-stimulated haematopoietic stem cells from peripheral blood in adults belongs to standard procedures in transplantology. The data on collection of G-CSF-stimulated bone marrow, both in adults and children, are lacking.

Objective: Analysis of the possibility and safety of use of G-CSF-stimulated haematopoietic stem cells from bone marrow in paediatric allogeneic sibling donor setting.

Patients And Methods: The prospective study included 10 children aged 3-17 years (median 13 years). Donors (aged 5-30 years, median 13 years; including 7/10 aged <18 years) were given subcutaneous G-CSF as 5 03BC g/kg/24 h for 2-4 days before bone marrow collection. Follow-up lasted 0.3-2.1 years.

Results: In none of the donors any serious adverse effects related to G-CSF or stem cell collection were observed. Median number of transplanted mononuclear cells (MNC) and CD3 4 cells was 10 x 10;8/ /kg (range, 5-12.7 x 10;8/kg) and 1.7 x 10;6/kg (range, 0.5-4.7 x 10;6/kg), respectively. All patients had granulocyte and platelet recovery with median time 16 days (range, 11-23 days) i 16 days (range, 12- -39 days), respectively. Overall, 4/10 patients had acute graft-versus-host disease (GVHD) > or =2 degrees and 2/10 patients had chronic GVHD (1 localized and 1 systemic). Higher cell-dose was not related to higher risk of acute or chronic GVHD. One-year probability of event-free-survival was 51.4%.

Conclusions: Collecting G-CSF primed bone marrow from paediatric donors is a safe and promising concept, and may help to obtain higher MNC and CD 34 cell dose from the donor. Benefits to recipient may occur related to faster engraftment after myeloablative transplantation without increasing the risk of GVHD. This concept requires further studies to evaluate this approach.