Cytokine Gene Expression in Peripheral Blood Mononuclear Cells after Allogeneic Blood Stem Cell Transplantation

Abstract

GVHD is one of the major complications of allogeneic bone marrow transplantation (allo BMT). Although it is mainly caused by donor T lymphocytes, cytokines play a central role in the regulation of immune responses, one manifestation of GVHD being the dysregulation of cytokines. Therefore, we have investigated inflammatory cytokine (IL-1β, IL-6, TNF-α), immunostimulatory cytokine (IL-2, IFN-γ) and immunosuppressive cytokines (IL-4, IL-10, IL-13) mRNA expression in peripheral blood mononuclear cells (PBMC) after allogeneic blood stem cell transplantation. This study shows that inflammatory cytokine mRNA expression in PBMC from severe GVHD (≥grade III) patients increased compared with PBMC from allo BMT without severe GVHD and auto BMT patients. In contrast, immunosuppresive cytokine mRNA expression increased in patients without severe GVHD. On the other hand, immunostimulatory cytokine mRNA expression remained fairly consistent during GVHD. Therefore, it is suggested that the cytokine network system shifted to enhance inflammatory cytokines in severe GVHD patients, but to enhance the immunosuppresive cytokines in patients without severe GVHD.