3A). Hematoxylin and eosin after 24 hours of reperfusion showed increased hepatocellular injury with swelling and fatty changes in wild-type mice compared to mice null for CD39 (Supporting Fig. 2A,B). Cytokine profiling

from serum taken after 3 hours of reperfusion reveals decreased circulating proinflammatory cytokines (Fig. 3B). In order to represent an outcome parameter of potential clinical implication, the area of necrosis was assessed after 4 days of reperfusion.22 Representative images of hematoxylin and eosin staining of liver injury after 4 days of reperfusion are shown in Fig. 3C,D. Long-term effects of liver injury were determined PCI-32765 chemical structure by measurement of the area of liver necrosis at day 4 after ischemia (Fig. 3E). CD39 is the dominant ectonucleotidase on the systemic endothelium but is absent on quiescent liver sinusoidal endothelial cells with heightened expression noted with liver injury and regeneration on proliferating cells.18 We undertook to analyze expression patterns of CD39 on sinusoidal nonendothelial cells and to determine how these this website affected responses after IRI. To examine the contributions of the endothelial versus myeloid and immune

cell components, wild-type mice were reconstituted with bone marrow from wild-type or CD39-null mice after lethal total body irradiation. Transfer of wild-type bone marrow was associated with significantly more injury after 3 hours of hepatic reperfusion, Erythromycin when compared to transfer of bone marrow from CD39-null mice (Fig. 4A). Expansion of hepatic NK and NKT cells was assessed 3 hours after reperfusion by measuring fractions of intrahepatic

lymphocytes. At this time point, expansion of NK cells was observed in wild-type and CD39-null mice (Fig. 4B). The fraction of NK cell population of the entire hepatic mononuclear cells was significantly higher in mice null for CD39. At these same time points, no significant expansion of hepatic NKT cells was observed (Fig. 4C). Next, we tested whether CD39 on NKT cells alone can directly modulate hepatic IRI in immunodeficient, reconstituted mice. This was done via adoptive transfer of purified NKT cells (CD3-positive, NK1.1-positive) to Rag1-null mice (which lack T cells, B cells, and NKT cells but contain NK cells). No difference was seen in hepatic injury measured as ALT elevation after adoptive transfer of either CD39-null or of wild-type NKT cells (Fig. 4D). At 24 hours after reperfusion, however, there was significantly less injury in nonreconstituted mice (without previous cell transfer; phosphate-buffered saline used as a vehicle control) when compared to the two reconstituted groups. IFNγ seems to be crucial in mediating at least some of the manifestations of hepatic and renal IRI.