GVHD remains the major complication of allogeneic BM transplantation and is initiated during the conditioning of the recipient for transplant when the host tissues are damaged. Research has demonstrated that the gastrointestinal (GI) tract is a critical organ in GVHD pathophysiology. Agents that protect the GI tract may provide prophylaxis against the cytokine cascade and can lead to a reduced incidence and severity of GVHD. KGF is a protein that stimulates the growth of epithelial cells including those of the GI tract. KGF can protect the GI tract, prevent GVHD, and preserve donor T-cell function.