Young child as a donor of cells for transplantation and lymphocyte based therapies.

In most cases of hematopoietic cell transplantation (HSCT) in pediatric recipient, the priority is given to bone marrow as a hematopoietic cell (HSC) source. The same expectations should be given to pediatric sibling donor. Bone marrow (BM) harvest is a standard method of HSC collection in pediatric siblings, however peripheral blood HSC (PBSC) collection is safe in healthy pediatric donors, and target hematopoietic cell yields can be achieved. Bone marrow or peripheral blood cell collection, both hematopoietic cells and lymphocytes, in pediatric sibling donors is safe, however there is a small risk of severe adverse events (SAE); still the risk of SAE is lower in children than in adults. The early adverse effects (AE) both after BM and PBSC collection are mild, short-term and easy to prevent or control, however they can occur in a relatively large proportion of donors. The risk of mild AE is lower in children than in adults, except PBSC collection in children <20 kg, who might be at risk of various complications. Short-term G-CSF administration and PBSC collection in pediatric donors is safe. No data exist on long-term adverse effects of short-term G-CSF course. Pediatric donors and their parents must be informed about the risk of possible complications.