Figure 7.

Histopathologic and immunohistochemical analysis of X-GVHD in NOD/SCID-β2m^null mice. NOD/SCID-β2m^null mice were sublethally irradiated with 300 cGy of TBI and injected r.o. with 10 × 10⁶ naive or 10 × 10⁶ activated huT cells. Moribund animals with X-GVHD were euthanized and portions of skin, liver, small intestine, colon, lung, kidney, salivary gland and spleen were saved for histopathologic and immunohistochemical analyses. (A) Liver from a mouse that did not show clinical or histological signs of X-GVHD following injection of huT. This liver shows an unremarkable portal tract and healthy hepatocytes. (B,C) X-GVHD in the liver characterized by (B) dense lymphocytic infiltrates in the portal tract and hepatocyte apoptosis, and (C) endotheliitis (head arrows). (D) X-GVHD in the lung showing perivascular and interstitial lymphocytic infiltration. (E) X-GVHD in the skin showing apoptosis and basal vacuolar damage of the keratinocytes. (F) X-GVHD in the colon showing apoptosis in the mucosa. (G) X-GVHD in the kidney showing prominent perivascular lymphocytic infiltration. (H) An example of immunohistochemical stains showing huT cells in X-GVHD expressing human CD45 in the spleen, (I,J) portal lymphocytes in liver X-GVHD consisting of huT lymphocytes expressing either human CD4 (I) or human CD8 (J). Slides in panels B–G were obtained from mice that received activated huT cells. Slides in panels A and H–J were obtained from mice that received naive huT cells. There were no significant differences in the pathologic damage originated by naive or activated huT cells. Black arrows indicate apoptotic cells.