Allogeneic transplant recipients with GVHD showed increase of periluminal mononuclear infiltrates. The pathology scores of mock-infected mice and mice 7 days after intranasal HSV-1 infection were determined. Data represent means ± SE of individual mice, derived from at least two separate experiments. Numbers of mock-infected mice were: 11 (normal CBA), 9 (allogeneic GVHD), 6 (allogeneic No GVHD), and 2 (syngeneic). Numbers of infected mice were: 17 (normal CBA), 13 (allogeneic GVHD), 8 (allogeneic No GVHD), and 4 (syngeneic). The asterisks indicate a significant difference from both normal CBA and allogeneic No GVHD (P = .05; Student'st-test).