Prof. Hellmann is author and co- author of more than 300 peer–reviewed articles in medical journals including NEJM and Blood. During a period 2005 – 2008 Prof. Hellmann was acting as a vice – rector of Medical University of Gdańsk. From 2003 till 2011Prof. Hellmann was the president of the Polish Society of Hematology and Transfusion Medicine. He is also the chairman of CML Study Group within the Polish Adult Leukemia Group. He is also the member of European Leukemia Network, American Society of Hematology, European Hematology Association, European Group for Blood and Marrow Transplantation, and International Society of Hematology. His special practical and research interest is still focused on myeloproliferative neoplasms.

Field of scientific activity:
Hematology, coagulation, transplantology. Among others, there are conducted molecular studies in myeloproliferative neoplasms which are applied for formulation of new standards in the targeted therapy for such disorders. The team is also engaged in studies of hematopoietic chimerysm after allogenic bone narrow transplantation.

Main achievements:
Hematopoietic stem cells transplantation (HSCT) mplemented into clinical practice. The implementation of Treg lymphocytes for the treatment of graft-versus-host disease.