Figure 1.

The three phases of acute GVHD, as described by Ferrara and colleagues. (from: Hill GR, Ferrara JLM. The primacy of the gastrointestinal tract as a target organ of acute graft-versus-host disease: rationale for the use of cytokine shields in allogeneic bone marrow transplantation. Blood 2000;95:2754–2759. Copyright American Society of Hematology, used by permission).