Cytokine-induced upregulation of hepatic intercellular adhesion molecule-1 messenger RNA expression and its role in the pathophysiology of murine endotoxin shock and acute liver failure

Neutrophil-induced liver injury during endotoxemia is dependent on the adhesion molecule Mac-1 (CD11b/CD18) on neutrophils. The potential involvement of its counterreceptor, intercellular adhesion molecule—1 (ICAM-1), in the pathogenesis was investigated after administration of 100 μg/kg Salmonella abortus equi endotoxin (ET) in galactosamine-sensitized mice (Gal). In ETsensitive mice (C3Heb/FeJ), which generated large amounts of tumor necrosis factor—alpha (TNF-α), massive neutrophil infiltration and severe liver injury were observed. In an ET-resistant strain (C3H/HeJ), which did not generate TNF-α, Gal/ET failed to cause neutrophil accumulation or injury. ICAM-1 messenger RNA (mRNA), negligible in control livers, was selectively induced by Gal/ET in ET-sensitive mice. Intravenous injection of murine TNF-α, interleukin-1 alpha (IL-1α) or IL-1β (13 to 23 μg/kg) strongly induced the ICAM-1 message in both strains, showing a comparable capacity for ICAM-1 mRNA synthesis. All cytokines caused similar neutrophil accumulation in the liver; however, only Gal/ TNF-α also caused upregulation of Mac-1 on circulating neutrophils and liver injury. The anti-murine ICAM-1 monoclonal antibody YN.1 (3 mg/kg) attenuated liver injury in ET-sensitive mice by 67% to 90% compared with isotype-matched control antibody-treated animals but did not reduce neutrophil accumulation in hepatic sinusoids. Our data suggest that the cytokines TNF-α and IL-1 are the main mediators responsible for upregulation of ICAM-1 mRNA in the liver during endotoxemia. The upregulation of both adhesion molecules, ICAM-1 and Mac-1, is necessary for a neutrophil-induced liver injury to occur. Blocking ICAM-1 and/or interfering with ICAM1 induction could be a successful therapeutic strategy to prevent sepsis-related inflammatory liver injury.     

Effect of FK506 on the activation state of hepatic macrophages in Propionibacterium acnes-treated rats

Activated hepatic macrophages can provoke massive liver necrosis following endotoxin stimulation through microcirculatory disturbances due to sinusoidal fibrin deposition in rats pretreated with heat-killed Propionibacterium acnes. In these rats, FK506 (tachlorinus) administered 24 h before and at the time of endotoxin injection, significantly attenuated liver injury compared with the rats given no FK506. The effect of FK506 on hepatic macrophage activation and its action sites were studied in Propionibacterium acnes-treated rats. When rats received Propionibacterium acnes intravenously, hepatic-mRNA expression of interferon-γ-inducing factor and interleukin-2 and splenic-mRNA expression of interferon-γ were significantly increased compared with normal rats. Hepatic-mRNA expression of CD14, a receptor for lipopolysaccharide and its binding protein complex, was also increased preceding the expressions of the three cytokines in the liver and spleen. FK506 administration attenuated hepatic-mRNA expression of interleukin-2 and both superoxide anions as well as tumour necrosis factor-α production by hepatic macrophages, but did not change CD14-mRNA expression in Propionibacterium acnes-treated rats. It is suggested that a cytokine network through interferon-γ-inducing factor, interferon-γ and interleukin-2 may operate during activation of hepatic macrophages in rats treated with heat-killed Propionibacterium acnes, while CD14 expression on the cells may increase independently of this network. FK506 seems to attenuate such activation by suppressing hepatic interleukin-2 expression, without affecting CD14 expression on the cells.     

Provocation of massive hepatic necrosis by endotoxin after partial hepatectomy in rats

When rats received endotoxin 48 hours after two-thirds liver resection, 50% of them died within 12 hours with massive hepatic necrosis at a dose that did not affect sham-operated rats. In the hepatic sinusoids, fibrin deposition and endothelial cell destruction occurred 5 hours after endotoxin administration. When antithrombin III concentrate was infused concomitantly with endotoxin administration, all rats survived 12 hours, and the extent of hepatic necrosis and the deranged serum glutamic pyruvic transaminase values were significantly attenuated at 5 hours compared with those in the control rats. Similar improvements in the incidence of mortality and liver injury were observed after treatment with gum arabic before hepatectomy. The stimulatory state of Kupffer cells based on the ability to produce superoxide anions estimated by formazan deposition after liver perfusion with nitro blue tetrazolium and phorbol myristate acetate was increased between 24 and 72 hours after operation. This increase disappeared after gum arabic treatment. It is concluded that massive hepatic necrosis can occur as a result of sinusoidal fibrin deposition provoked by endotoxin in partially hepatectomized rats. Activated Kupffer cells may contribute to this provocation.     

Inhibition of macrophages with gadolinium chloride alters intercellular adhesion molecule-1 expression in the liver during acute endotoxemia in rats

Cell adhesion molecules are important for localized accumulation of phagocytes at sites of tissue damage. In the present studies, we analyzed the effects of blocking hepatic macrophages on expression of beta2 integrins and intercellular adhesion molecule-1 (ICAM-1) adhesion molecules on liver cells during acute endotoxemia. Flow cytometric analysis revealed distinct subpopulations of macrophages from control animals that varied on the basis of their size and density. In contrast, hepatocytes and endothelial cells were relatively homogeneous. Treatment of rats with endotoxin (5 mg/kg, intravenously) resulted in a time-dependent increase in the percentage of small, dense macrophages and a progressive loss of larger, less-dense cells. In contrast, no major effects were observed on the physical properties of hepatocytes or endothelial cells. ICAM-1 was found to be constitutively expressed on endothelial cells and hepatocytes, as well as on macrophages. Induction of acute endotoxemia resulted in a time-dependent increase in ICAM-1 expression on hepatocytes, which was observed within 3 hours and reached a maximum after 24 hours. An increase in ICAM-1 expression was also observed on endothelial cells and on macrophages at 3 hours, followed by a decrease at 24 to 48 hours. Macrophages and endothelial cells also constitutively expressed beta2 integrins. Induction of acute endotoxemia had no effect on beta2 integrin expression by these cells. Pretreatment of rats with gadolinium chloride (GdCl3), a macrophage inhibitor known to block endotoxin-induced liver injury, abrogated the effects of endotoxin on ICAM-1 expression by hepatocytes and macrophages. In contrast, ICAM-1 expression on endothelial cells increased. Interestingly, treatment of rats with GdCl3 alone resulted in a marked increase in expression of ICAM-1 on endothelial cells and hepatocytes, and of beta2 integrins on macrophages and endothelial cells. Taken together, these data suggest that ICAM-1 is involved in mediating macrophage adherence and accumulation in the liver during endotoxemia. Furthermore, macrophages appear to regulate expression of this cell adhesion molecule on parenchymal cells.     

Intravascular coagulation in the development of massive hepatic necrosis induced by Corynebacterium parvum and endotoxin in rats

When Escherichia coli endotoxin was intravenously injected into rats given killed Corynebacterium parvum 6 days previously, fibrin deposition and endothelial cell injury occurred in hepatic sinusoids at 1.5 h and were intensified thereafter. Serum alanine aminotransferase values were increased along with prothrombin time and decreased plasma levels of antithrombin III and coagulation factor VIII:C at 5 h. Antithrombin III concentrate (plus heparin) or superoxide dismutase infused concurrently with injection of endotoxin significantly attenuated the derangements of these variables and the histologic extent of liver injury at 5 h. Intravascular coagulation, probably developing through the action of superoxide anion, may contribute to the development of massive hepatic necrosis induced by C. parvum and endotoxin in rats.     

Release of soluble intercellular adhesion molecule 1 into bile and serum in murine endotoxin shock

Neutrophil-induced liver injury during endotoxemia is dependent on the adhesion molecules Mac-1 (CD11b/CD18) on neutrophils and its counterreceptor on endothelial cells and hepatocytes, intercellular adhesion molecule 1 (ICAM-1). To investigate a potential release of a soluble form of ICAM-1 (sICAM-1), animals received 100 micrograms/kg Salmonella abortus equi endotoxin alone or in combination with 700 mg/kg galactosamine. In endotoxin-sensitive mice (C3Heb/FeJ), injection of endotoxin did not cause liver injury but induced a time-dependent increase of sICAM-1 in serum (300%) and in bile (615%) without affecting bile flow. In galactosamine/endotoxin-treated animals, which developed liver injury, the increase in both compartments was only 97% and 104%, respectively. In either case, the increase in sICAM-1 concentrations paralleled the enhanced ICAM-1 expression in the liver. The endotoxin-resistant strain (C3H/HeJ) did not show elevated sICAM-1 levels in serum or bile after endotoxin administration. In contrast, the intravenous injection of murine tumor necrosis factor alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha) or IL-1 beta (13-23 micrograms/kg) into endotoxin-resistant mice induced a 225% to 364% increase in serum sICAM-1 and a 370% elevation of the biliary efflux of sICAM-1, again independent of changes in bile flow. These data indicate that cytokines are major inducers of sICAM-1 formation during endotoxemia in vivo. The described experimental model can be used to investigate the role of sICAM-1 in the pathophysiology of inflammatory liver disease. (Hepatology 1996 Mar;23(3):530-6)     

Gut-derived substances in activation of hepatic macrophages after partial hepatectomy in rats.

When liver perfusion with nitro blue tetrazolium and phorbol myristate acetate was performed in rats 24 h after two-thirds liver resection, there were marked deposits of formazan converted from nitro blue tetrazolium in hepatic macrophages throughout the liver, indicating macrophage activity. The extent of the deposits was significantly reduced when perfusion was performed following oral administration of polymyxin B sulfate, a non-absorbable bacteriocidal agent against gram-negative bacilli which can also bind endotoxin lipopolysaccharides. Polymyxin B sulfate administration also attenuated the derangements of SGPT and the histological liver injury provoked by endotoxin administration after partial hepatectomy. These results suggests that gut-derived substances sensitive to polymyxin B sulfate may contribute to activation of hepatic macrophages after partial hepatectomy in rats.     

Pathophysiologic importance of E- and L-selectin for neutrophil-induced liver injury during endotoxemia in mice

Neutrophils can cause parenchymal cell injury in the liver during ischemia-reperfusion and endotoxemia. Neutrophils relevant for the injury accumulate in sinusoids, transmigrate, and adhere to hepatocytes. To investigate the role of E- and L-selectin in this process, C3Heb/FeJ mice were treated with 700 mg/kg galactosamine and 100 microgram/kg endotoxin (Gal/ET). Immunogold labeling verified the expression of E-selectin on sinusoidal endothelial cells 4 hours after Gal/ET injection. In addition, Gal/ET caused up-regulation of Mac-1 (CD11b/CD18) and shedding of L-selectin from circulating neutrophils. Gal/ET induced hepatic neutrophil accumulation (422 +/- 32 polymorphonuclear leukocytes [PMN]/50 high power fields [HPF]) and severe liver injury (plasma alanine transaminase [ALT] activities: 4,120 +/- 960 U/L; necrosis: 44 +/- 3%) at 7 hours. Treatment with an anti-E-selectin antibody (3 mg/kg, intravenously) at the time of Gal/ET administration did not significantly affect hepatic neutrophil accumulation and localization. However, the anti-E-selectin antibody significantly attenuated liver injury as indicated by reduced ALT levels (-84%) and 43% less necrotic hepatocytes. In contrast, animals treated with an anti-L-selectin antibody or L-selectin gene knock out mice were not protected against Gal/ET-induced liver injury. However, E-, L-, and P-selectin triple knock out mice showed significantly reduced liver injury after Gal/ET treatment as indicated by lower ALT levels (-65%) and reduced necrosis (-68%). Previous studies showed that circulating neutrophils of E-selectin-overexpressing mice are primed and activated similar to neutrophils adhering to E-selectin in vitro. Therefore, we conclude that blocking E-selectin or eliminating this gene may have protected against Gal/ET-induced liver injury in vivo by inhibiting the full activation of neutrophils during the transmigration process.     

Deranged blood coagulation equilibrium as a factor of massive liver necrosis following endotoxin administration in partially hepatectomized rats

Activated Kupffer cells provoke massive liver necrosis after endotoxin stimulation through microcirculatory disturbance caused by sinusoidal fibrin deposition in rats undergoing 70% hepatectomy. In these rats, serum activities of purine nucleoside phosphorylase (PNP) and alanine transaminase (ALT) were increased at 1 and 5 hours, respectively, following endotoxin administration. When 70% resected liver was perfused with Dulbecco's modified Eagle medium (DMEM) containing heat-inactivated fetal calf serum, the increase in both enzyme activities was not affected by addition of endotoxin during perfusion, suggesting that activated Kupffer cells injured neither sinusoidal endothelial cells nor hepatocytes. The activity of tissue factor, an initiator of blood coagulation cascade, was much higher in Kupffer cells isolated from partially hepatectomized rats than in those from normal rats. In contrast, mRNA expressions of tissue factor pathway inhibitor (TFPI) as well as thrombomodulin were almost undetectable in normal and partially resected livers. When recombinant human TFPI was injected intravenously in 70% hepatectomized rats, TFPI was markedly stained on the surfaces of sinusoidal endothelial cells and microvilli of hepatocytes on immunohistochemistry. In these rats, endotoxin-induced liver injury was significantly attenuated compared with rats given no TFPI. Similar attenuation was also found in rats receiving recombinant human thrombomodulin. These results suggest that fibrin deposition developing in 70% hepatectomized rats after endotoxin administration may be caused by deranged blood coagulation in the hepatic sinusoids through increasing tissue factor activity in Kupffer cells and minimal TFPI and thrombomodulin in endothelial cells. The destruction of sinusoidal endothelial cells as well as hepatocytes may occur as a result of microcirculatory disturbance caused by such sinusoidal fibrin deposition.     

Impaired transendothelial migration by neonatal neutrophils: abnormalities of Mac-1 (CD11b/CD18)-dependent adherence reactions

In order to evaluate the functions of lymphocyte function antigen-1 (LFA-1) (CD11a/CD18) and Mac-1 (CD11b/CD18) on neonatal neutrophils, we examined neutrophil adhesion to and migration through human umbilical vein endothelial cell (HUVEC) monolayers in vitro. Transendothelial migration of adult neutrophils was greatly enhanced by preincubation of HUVEC with interleukin-1 (IL-1). This migration was significantly inhibited by monoclonal antibodies (MoAbs) against LFA-1 (CD11a) and Mac-1 (CD11b) subunits. Migration of neonatal neutrophils was markedly diminished compared to adult neutrophils, and MoAbs against LFA-1 further reduced migration. In contrast, anti-Mac-1 MoAb was not inhibitory. Adhesion of adult neutrophils was significantly enhanced by prestimulation of HUVEC with IL-1, and was significantly inhibited by MoAbs against LFA-1. Adhesion of neonatal neutrophils was near adult levels and comparably inhibited by anti-LFA-1 MoAb. In addition, adhesion of neonatal and adult neutrophils to purified ICAM-1 in artificial planar membranes was comparable and almost completely inhibited by anti-LFA-1 MoAb. Chemotactic stimulation induced Mac-1-dependent adhesion of adult neutrophils to endothelial cells, purified intercellular adherence molecule-1 (ICAM-1) and protein-coated glass. In marked contrast, adhesion of neonatal neutrophils to these substrates was not significantly increased by chemotactic stimulation. These findings indicate that diminished transendothelial migration by neonatal neutrophils is related to abnormal interactions of Mac-1 with ICAM-1 and possibly other endothelial ligands. These functional deficits may contribute to impaired inflammation and infectious susceptibility in human neonates.     

Use of prostaglandin I2 analog in treatment of massive hepatic necrosis associated with endothelial cell injury and diffuse sinusoidal fibrin deposition

Endothelial cell damage causes massive hepatic necrosis as a result of fibrin deposition in the hepatic sinusoids. When a stable analog of prostaglandin I₂, beraprost sodium, was administered to rats given either dimethylnitrosamine, carbon tetrachloride, or endotoxin followingCorynebacterium parvum administration, the hepatic necrosis produced in each was attenuated, but to a greater extent in the dimethylnitrosamine and endotoxin/Corynebacterium parvum models, where fibrin deposition in the hepatic sinusoids occurs, as compared to the carbon tetrachloride model, where such fibrin deposition does not occur. Beraprost sodium reduced the expected increase of portal venous pressure in the endotoxin/Corynebacterium parvum model without affecting plasma thrombin-antithrombin III complex levels. Beraprost sodium also significantly reduced cell killing of both isolated rat hepatocytes and hepatic sinusoidal endothelial cells exposed totert-butyl hydroperoxide when compared to controls. Beraprost sodium could prove to be a therapeutic candidate for the treatment of hepatic necrosis, particularly in cases associated with fibrin deposition in the hepatic sinusoids because of its fibrin clot-clearning action.     

Is the intercellular adhesion molecule-1/leukocyte function associated antigen 1 pathway of leukocyte adhesion involved in the tissue damage of alcoholic hepatitis?

Alcoholic hepatitis is characterised histologically by an intense inflammatory cell infiltrate made up predominantly of neutrophils but including other cell types, particularly lymphocytes. Leukocyte cytotoxicity requires cell adhesion, which is mediated via receptors on the leukocyte surface including leukocyte function associated antigen-1 (LFA-1) which binds to the ligand intercellular adhesion molecule-1 (ICAM-1) on the target cell. The distribution of ICAM-1 and LFA-1 expression in liver biopsy specimens from patients with alcoholic liver disease was examined to ascertain whether this pathway of leukocyte adhesion is involved in the tissue damage of alcoholic hepatitis. Specimens were stained for ICAM-1 and LFA-1 by a three step immunoalkaline-phosphatase method using monoclonal antibodies against ICAM-1 and LFA-1. LFA-1 staining on portal tract inflammatory cells and parenchymal inflammatory cells and ICAM-1 staining on liver components were examined. ICAM-1 expression on hepatocytes was significantly greater in alcoholic hepatitis compared with fatty liver (p less than 0.001) and normal controls (p less than 0.01). ICAM-1 expression correlated with the histological degree of hepatocellular damage (tau = 0.79; p = 0.0005) and parenchymal inflammation (tau = 0.65; p less than 0.001, and with LFA-1 expression on parenchymal leukocytes (tau = 0.63; p = 0.01). The ICAM-1/LFA-1 pathway may therefore be involved in leukocyte mediated tissue damage during alcoholic hepatitis.     

Chronic Ethanol Consumption Enhances Endotoxin Induced Hepatic Sinusoidal Leukocyte Adhesion

In alcoholic liver disease, endotoxin has been postulated to play an important role in its pathogenesis. Endotoxin is known to lead to impediment of hepatic microcirculation, including the adhesion of leukocytes to sinusoidal endothelial cells. In this study, the effect of chronic ethanol consumption on the leukocyte adhesion elicited by endotoxin was examined. Male Wistar rats were pair-fed with a liquid diet containing ethanol or an isocaloric control diet for 6 weeks. The liver of anesthetized rats were placed on the nonfluorescent cover-glass for observation by an intravital inverted microscope equipped with a silicon intensified target camera. The red blood cell (RBC) velocity in hepatic sinusoids was measured by an off-line temporal correlation velocimeter (Capiflow, Sweden) after intravenous injection of fluorescein isothiocyanate-labeled rat RBC. RBC velocity in sinusoids was more severely disturbed in ethanol fed rats than in controls. Leukocytes were stained by the intravenous injection of carboxyfluorescein succinimidyl ester for a fluorographic observation of leukocyte adhesion. After lipopolysaccharide injection, the number of adherent leukocytes was significantly greater in ethanol-fed rats than in controls. Plasma tumor necrosis factor-α levels were also higher in ethanol-fed rats than in controls. These results suggest that chronic ethanol consumption aggravates endotoxin induced leukocytes adhesion that may result in hepatic microcirculatory disturbances. Leukocyte adhesion to the sinusoidal wall may be associated with increased in tumor necrosis factor-α levels.     

Neutrophil depletion protects against murine acetaminophen hepatotoxicity

We previously reported that liver natural killer (NK) and NKT cells play a critical role in mouse model of acetaminophen (APAP)-induced liver injury by producing interferon gamma (IFN-gamma) and modulating chemokine production and subsequent recruitment of neutrophils into the liver. In this report, we examined the role of neutrophils in the progression of APAP hepatotoxicity. C57BL/6 mice were given an intraperitoneal toxic dose of APAP (500 mg/kg), which caused severe acute liver injury characterized by significant elevation of serum ALT, centrilobular hepatic necrosis, and increased hepatic inflammatory cell accumulation. Flow cytometric analysis of isolated hepatic leukocytes demonstrated that the major fraction of increased hepatic leukocytes at 6 and 24 hours after APAP was neutrophils (Mac-1+ Gr-1+). Depletion of neutrophils by in vivo treatment with anti-Gr-1 antibody (RB6-8C5) significantly protected mice against APAP-induced liver injury, as evidenced by markedly reduced serum ALT levels, centrilobular hepatic necrosis, and improved mouse survival. The protection was associated with decreased FasL-expressing cells, cytotoxicity against hepatocytes, and respiratory burst in hepatic leukocytes. In intracellular adhesion molecule (ICAM)-1-deficient mice, APAP caused markedly reduced liver injury when compared with wild-type mice. The marked protection in ICAM-1-deficient mice was associated with decreased accumulation of neutrophils in the liver. Hepatic GSH depletion and APAP-adducts showed no differences among the antibody-treated, ICAM-1-deficient, and normal mice. In conclusion, accumulated neutrophils in the liver contribute to the progression and severity of APAP-induced liver injury.     

ICAM-1 mediates lung leukocyte recruitment but not pulmonary fibrosis in a murine model of bleomycin-induced lung injury.

Bleomycin-induced lung injury has been extensively used as a model of interstitial pneumonia and pulmonary fibrosis. Intercellular adhesion molecule (ICAM)-1 is a ligand for lymphocyte function-associated antigen (LFA)-1alpha and has been shown to be required for leukocyte migration into inflamed areas. The purpose of this report was to investigate the role of the ICAM-1/LFA-1alpha pathway in a murine model of bleomycin-induced lung injury. Animals received 75 mg x kg(-1) bleomycin (BLM) i.v. followed by treatment with phosphate-buffered saline (BLM group), anti-ICAM-1 and LFA-1alpha monoclonal antibodies (mAb) (BLM+mAb group). Inflammatory cell counts of bronchoalveolar lavage (BAL) fluid, hydroxyproline content and histological findings were compared between these groups. In the BLM group, significant increases in total cell count, macrophage count and neutrophil count of BAL fluid were observed on days 7 and 14. In the BLM+mAb group, bleomycin-induced accumulation of neutrophils was significantly reduced on days 7 and 14 (p<0.01). However, the administration of mAb to ICAM-1 and LFA-1alpha did not decrease the lung hydroxyproline content or the histopathological fibrosis grading score, indicating that the antagonism of ICAM-I and LFA-1alpha did not attenuate bleomycin-induced pulmonary fibrosis. This study suggests that the intercellular adhesion molecule-1/lymphocyte function-associated antigen-1alpha pathway mediates the accumulation of inflammatory cells in the injured lung caused by bleomycin; however, other mechanisms are important for the subsequent development of pulmonary fibrosis.     

Activated protein C prevents multiple organ injury following extensive hepatectomy in cirrhotic rats

BACKGROUND/AIMS: Extended hepatectomy for cirrhotic liver in patients with hepatocellular carcinoma often triggers posthepatectomy liver failure. It has been shown that the microcirculatory disturbance caused by microthrombus formation and sinusoidal endothelial cellular injury is one of the causes of post-hepatectomy liver dysfunction. We therefore investigated the effect of activated protein C (APC), a potent antithrombotic serine protease with anti-inflammatory effects, on posthepatectomy liver dysfunction and multiple organ injury in cirrhotic rats. METHODS/RESULTS: Dimethylnitrosamine-induced cirrhotic rats underwent 70% hepatectomy and received lipopolysaccharide (200 microg/kg) 48 h later to prepare a lethal posthepatectomy acute liver failure model. APC (1500 U/kg), given intravenously 15 min before and 1 h after endotoxin challenge, attenuated liver dysfunction and decreased serum tumor necrosis factor-alpha concentration. APC significantly improved the survival rate of rats at 12 h after endotoxin challenge. Histological examination revealed that APC treatment inhibited not only intrasinusoidal fibrin deposition and massive hepatocellular necrosis but also pulmonary injury and glomerular fibrin deposition. Immunohistochemically, expression of intercellular adhesion molecule-1 on sinusoidal cells and renal glomeruli was decreased in the APC-treated animals. CONCLUSIONS: APC administration prevented acute liver dysfunction and attenuated multiple organ injury following extended hepatectomy in cirrhotic rats, possibly via anticoagulant and anti-inflammatory effects.     

Immunological reactions in liver graft perireperfusion in living donor liver transplantation--change of expression of adhesion molecules,deposition of immunoglobulins and cytokine level

BACKGROUND/AIMS: In liver transplantation from living donors, injury of graft by operative procedure might be a potential risk for the deterioration of the liver graft. To clarify influences of the surgical procedures on the graft we investigated indices of immunological reactions in the graft and change of blood cytokine levels in the early period after transplantation. METHODOLOGY: Subjects were ten patients who received living donor liver transplantation. Two cases with ABO incompatibility and one case with positive crossmatch were included. Liver biopsy was taken at laparotomy, graftectomy, 6 hours after reperfusion. Liver function parameters, blood cytokines (IL-6, IL-8, and TNF alpha), expression of adhesion molecules (ICAM-1, ELAM-1, LFA-1 and SleX), and immunoglobulins deposition in the graft were examined to evaluate the degree of immunological reaction. RESULTS: Slight elevation of the total bilirubin and ALT was recognized after reperfusion. Elevation of blood cytokine levels was observed six hours after reperfusion and these values normalized within two days. Expressions of adhesion molecules in vessels were not enhanced except ELAM-1 of the hepatic vein. Infiltration of LFA-1 or SleX-positive cells was observed at graftectomy and reperfusion. No increment of IgG deposition was recognized in vessels even in anti-donor antibody positive cases but deposition of IgA and IgM increased only in the sinusoids. CONCLUSIONS: These results suggested that immunological reactions were generated by the operative procedure in the liver graft to some extent but the graft viability was not severely affected and that antibodies did not play important roles in liver injury in the early period after transplantation, even in anti-donor antibody positive cases.     

Sinusoidal endothelial cell injury by superoxide anion and iron in the Propionibacterium acnes-pretreated and lipopolysaccharide-stimulated rat liver

AIMS/BACKGROUND: We attempted to measure the generation of superoxide anion, examine its site of release and determine its pathological role in Propionibacterium acnes-lipopolysaccharide-induced liver injury in the rat. METHODS: The P. acnes-pretreated (16 mg/kg i.v.) rat liver was perfused with buffer containing lipopolysaccharide (2.5 microg/ml). Chemiluminescence enhanced with Cypridina luciferin analog, MCLA, and reduction of nitro blue tetrazolium were used for detecting superoxide anion. Leakage of enzymes and release of cytokines into the perfusate, and histological specimens were also examined. RESULTS: Superoxide dismutase-inhibitable chemiluminescence peaked at 30 min of lipopolysaccharide infusion and blue formazan precipitate was histochemically deposited mainly on hepatic macrophages. Purine nucleoside phosphorylase (PNP) activity in the perfusate, as a marker of sinusoidal endothelial cell injury, reached its maximum at 50 min and aspartate aminotransferase (AST) activity, as a marker of hepatocyte injury, reached a plateau at 90 min. Simultaneous treatment with superoxide dismutase and deferoxamine mesylate significantly suppressed the leakage of PNP and AST. Release of tumor necrosis factor-alpha and growth-related oncogene/cytokine-induced neutrophil chemoattractant-1 lagged behind PNP leakage. Light microscopy showed destruction of the sinusoids followed by hepatocyte necrosis. Electron microscopy revealed adherence of hepatic macrophages to sinusoidal endothelial cells. CONCLUSION: These results indicate that superoxide anion released from hepatic macrophages may induce sinusoidal endothelial cell injury via interaction with iron in the P. acnes-lipopolysaccharide-treated liver.     

Role of the spleen in endotoxin-induced hepatic injury in chronic alcohol-fed rats.

The present experiments were designed to study the role of the spleen in endotoxin-induced hepatic injury in chronic alcohol-fed rats. Administration of 2 mg/kg body weight of endotoxin caused severe hepatic injury in chronic alcohol-fed rats as compared with controls. This injury was significantly less in those whose spleens had been resected 1 week prior to endotoxin administration. There were no differences in plasma endotoxin levels 16 h after intravenous injection of endotoxin between sham-operated control rats, and chronic alcohol-fed rats with and without splenectomy. The plasma tumor necrosis factor (TNF) level 1 h after intravenous injection of endotoxin was significantly higher in chronic alcohol-fed rats than in controls. However, TNF levels were significantly lower in those with splenectomy. Neutrophil infiltration was seen in the liver sinusoid of sham-operated chronic alcohol-fed rats as early as 1 h after injection of endotoxin, and was observed even 15 h later. These results suggest that endotoxin-induced liver injury is closely related to factors derived from the spleen and induced by plasma endotoxin, especially when Kupffer cell function is reduced by chronic alcohol feeding. In addition, TNF and neutrophils may play an important role in this type of liver injury.     

Role of the spleen in endotoxin-induced hepatic injury in chronic alcohol-fed rats

ABSTRACT— The present experiments were designed to study the role of the spleen in endotoxin-induced hepatic injury in chronic alcohol-fed rats. Administration of 2 mg/kg body weight of endotoxin caused severe hepatic injury in chronic alcohol-fed rats as compared with controls. This injury was significantly less in those whose spleens had been resected 1 week prior to endotoxin administration. There were no differences in plasma endotoxin levels 16 h after intravenous injection of endotoxin between sham-operated control rats, and chronic alcohol-fed rats with and without splenectomy. The plasma tumor necrosis factor (TNF) level 1 h after intravenous injection of endotoxin was significantly higher in chronic alcohol-fed rats than in controls. However, TNF levels were significantly lower in those with splenectomy. Neutrophil infiltration was seen in the liver sinusoid of sham-operated chronic alcohol-fed rats as early as 1 h after injection of endotoxin, and was observed even 15 h later. These results suggest that endotoxin-induced liver injury is closely related to factors derived from the spleen and induced by plasma endotoxin, especially when Kupffer cell function is reduced by chronic alcohol feeding. In addition, TNF and neutrophils may play an important role in this type of liver injury.