A Possible Association between the Presence of Interleukin-4-Secreting Cells and a Reduction in the Risk of Acute Graft-Versus-Host Disease.

We monitored interleukin-4 (IL-4), interferon-gamma (IFN-g), and tumor necrosis factor alpha (TNF-a)-secreting cells using an enzyme-linked immunospot (ELISPOT) assay in a prospective study to assess the cytokine network after transplantation. Peripheral blood mononuclear cells were collected from 23 patients who received allogeneic stem cell transplantation, from before the preconditioning regimen to 56 days after transplantation. The frequency of IL-4-secreting cells was significantly higher in 5 patients receiving peripheral blood stem cell transplantation (PBSCT) than that in 18 patients who received bone marrow transplantation (BMT). Based on IFN-g and TNF-a release, there was a trend toward a decrease in the number of cytokine-secreting cells in PBSCT. Furthermore, patients who did not develop acute graft-versus-host disease (GVHD, n = 5) showed a significantly higher number of IL-4-secreting cells compared with those who developed acute GVHD (n = 18). These results indicate that the high percentage of IL-4-secreting cells may be responsible for the inhibition of acute GVHD. In addition, the increased percentage of IL-4-secreting cells may be responsible for the unexpected low incidence of acute GVHD in PBSCT, despite the presence of large numbers of mature T cells in the donor infusion.