Kinetics of serum cytokines after allogeneic bone marrow transplantation: interleukin-5 as a potential marker of acute graft-versus-host disease.

Cytokine levels in sera from 14 patients undergoing allogeneic bone marrow transplantation (alloBMT) or donor lymphocyte infusion (DLI) were sequentially measured to evaluate the roles of cytokines in clinical graft-versus-host disease (GVHD). In clinical courses, interleukin (IL)-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma were measured by enzyme-linked immunosorbent assay. Among the evaluable cases, 6 patients developed acute GVHD. Serum IL-5 levels increased to more than 100 pg/mL in 5 of the 6 patients before, or simultaneously with, the clinical manifestation of acute GVHD. Elevation of IL-5 was transient in 3 patients. In the other 2 patients who showed regimen-related toxicity and/or thrombotic microangiopathy as well as acute GVHD, remarkable and sustained elevation of the serum IL-5 level was observed. In 7 patients without acute GVHD, IL-5 levels remained below 100 pg/mL. An association of acute GVHD was less prominent with TNF-alpha than with IL-5 in our study. Elevation of IL-6 was associated with infections. In 2 patients with severe extensive chronic GVHD, serum IL-10 was elevated in parallel with exacerbation of clinical symptoms. Our findings suggest that an elevated serum IL-5 level may be a marker of acute GVHD.