125 – Impact of G-CSF mobilization on T-cell functionality: New aspects for adoptive immunotherapy

Hematopoietic stem cell transplantation (HSCT) with peripheral blood stem cells (PBSC) mobilized with granulocyte-colony-stimulating factor (G-CSF) is related to a faster engraftment and reduced transplant-related mortality. PBSC products contain more than 10-fold higher number of T cells when compared to bone marrow (BM), leading in most trials to similar rates of acute graft-versus-host disease (aGvHD). Higher viral reactivation rates were shown in PBSCT recipients early after transplantation, while antiviral immunity after 100 days was comparable to BMT. A transient delay in T-cell immunity may be the reason, since it was shown that G-CSF-treatment induces immunologic tolerance and negatively affect T-cell functionality.