Investigating Cytokine Genes of Stem Cell Donors

The NHLBI Stem Cell Allotransplantation Program is researching methods to improve allogeneic stem cell transplantation. We are particularly interested in identifying factors, which result in individual variability in outcomes. Cytokines are biological modulators of the immune system known to influence various phases of the immune response. Normal variations in the genetic material coding for cytokines (Cytokine Gene Polymorphisms or CGPs) are believed to account for some of the differences in the inflammatory response between individuals. In the future, we hope to tailor stem cell transplantation to take into account these immunological profiles. In order to characterize the effect of any such intervention, we first need to better understand the role CGPs play in immune responses in normal, healthy persons. This involves testing for the presence or absence of a polymorphism in healthy individuals, and comparing with a validated in vitro assay. None of these polymorphisms are associated with known clinical disease to be classifiable as a 'genetic defect'. Moreover, we will not correlate these polymorphisms with clinical studies to identify traits in the sample donors. We plan to utilize stored blood samples from stem cell transplant donors who have previously participated on a hematology branch protocol as well as consent future donors.