[Proteins support stem cells - use of protein therapeutics in hematopoietic stem cell transplantation]

Hematopoietic stem cell transplantation (HSCT) has evolved from a largely experimental therapeutic approach three decades ago to a well-established therapy today for many malignant and non-malignant disorders of the hematopoietic and the immune system. Although it is per se a therapy by transmission of cells, protein therapeutics such as growth factors and antibodies are relevant in all phases of a HSCT and substantially contribute to the success of this often only curative treatment. This review discusses HSCT with a particular focus on the protein therapeutics involved. Granulocyte colony stimulating factor (G-CSF) for mobilization of stem cells to the peripheral blood, the polyclonal anti-T-cell globulin (ATG) and the monoclonal antibodies alemtuzumab and etanercept for prophylaxis and therapy of graft versus host disease (GvHD) are highlighted. Also rituximab, palivizumab and polyclonal intravenous immunoglobulins for treating infections in post-transplant patients are discussed. Since our understanding of cell surface receptors, cytokine and signaling pathways is increasing, there will emerge new targets for directed therapy by proteins in the future. They may have the potential to further improve the success and to widen theapplication of HSCT.