Allogeneic transplant recipients with GVHD showed increased pathology. Photomicrographs of lung sections stained with hematoxylin and eosin show evidence of increased pathology in infected allogeneic GVHD mice. (A) Normal CBA, mock-infected, original magnification × 25; (B) normal CBA, mock-infected, original magnification × 100; (C) normal CBA, infected, original magnification × 40; (D) normal CBA, infected, original magnification × 100; (E) allogeneic GVHD, mock-infected, original magnification × 10; (F) allogeneic GVHD, mock-infected, original magnification × 75; (G) allogeneic GVHD, infected, original magnification × 10; (H) allogeneic GVHD, infected, original magnification × 100.