Impaired immune function in obstructive jaundice

The molecular basis for the immunomodulatory activities of unconjugated bilirubin

Nearly a century ago, jaundiced patients were observed to have surprising and spontaneous remissions from incurable immunologic diseases including rheumatoid arthritis, allergy, and asthma. The mystery of why this phenomenon occurred remains unresolved to this day. Bilirubin has traditionally been considered an excretory product resulting from heme metabolism with little benefit to human physiology. In the past few decades, however, the salutary role of this byproduct as a potent antioxidant has been repeatedly noted. Most recently, the molecule has been found to possess immunomodulatory properties that rival its redox capacity, possibly explaining its ability to suppress inflammation. In this review, we specifically examine unconjugated bilirubin (UCB) as an immunomodulator and explore the molecular basis for its immunosuppressive effects.

Percutaneous transhepatic biliary drainage

Over the past three decades, endoscopic and percutaneous biliary drainage have become readily available in most hospital settings and these minimally invasive techniques have revolutionized the treatment of patients with biliary obstruction. In the past, treatment of biliary obstruction had required surgery under general anesthesia and an extended hospital stay. Currently, the same patient can most often be treated either endoscopically as an outpatient or during a short hospital stay after percutaneous drainage under moderate sedation. This article reviews the indications and technique of percutaneous transhepatic cholangiography and biliary drainage.

Patient preparation before surgery for cholangiocarcinoma

AIM

Multiorgan dysfunction is often encountered in jaundiced patients and may compromise the postoperative outcome after liver resection for cholangiocarcinoma (CCA). The aim of the present study was to elucidate evidence-based medicine regarding the benefit of the available preoperative treatments currently used for the preparation of patients before surgery for hilar CCA.

MATERIAL AND METHODS

An electronic search using the Medline database was performed to identify relevant articles relating to renal dysfunction, bacterial translocation, hemostasis impairment, malnutrition, liver failure, and postoperative outcome in jaundiced patients undergoing liver resection for CCA.

RESULTS

There is grade B evidence to expand the extracellular water volume and to administer oral synbiotic supplements. Intravenous vitamin K administration is an effective treatment. Perioperative nutritional support should be administered preferably by the enteral route in severely malnourished patients with compromised liver function undergoing extended liver resection (grade A evidence). There is only grade C evidence to recommend a portal vein embolization in patients with CCA when the future remnant liver volume is <40%.

CONCLUSIONS

A simplified scheme that might be useful in the management of patients presenting with obstructive jaundice was presented. Despite surgical technique improvements, preparation of patients for surgery will continue to be one of the major determinants for the postoperative prognosis of jaundiced patients.

A new technique of biliary reconstruction after "high hilar resection" of hilar cholangiocarcinoma with tumor extension to secondary and tertiary biliary radicals

BACKGROUND

Radical operation for hilar cholangiocellular carcinoma, including extended hepatic resection, seems to improve prognosis by increasing the surgical curability rate. Nevertheless, high postoperative morbidity and mortality have been reported in patients with obstructive jaundice. We describe the technique of "high hilar resection" and a modification of bilioenteric anastomosis for drainage of the multiple secondary or tertiary biliary radicals.

METHODS

Ten patients with advanced hilar cholangiocellular carcinoma underwent a high hilar resection with complete parenchymal preservation, and the biliary drainage was reconstructed by a sheath-to-enteric hepaticojejunostomy. Because of the technical difficulty caused by anastomosis line in the range of the biliary sheath, a modification was performed by dividing the biliary apertures of segments 5 and 4b.

RESULTS

A high hilar resection was successfully performed, and all patients were discharged from the hospital in good condition. No patient died postoperatively. The proximal resection margin was tumor-free in all patients. One patient died after 29 months of peritoneal carcinomatosis. None of the patients developed local recurrence around the hepaticojejunostomy. The remaining nine patients are alive after a mean follow-up of 28.8 months after surgery without any signs of recurrence.

CONCLUSION

In highly selected patients with advanced hilar cholangiocellular carcinoma, a high hilar resection is technically safe and oncologically justifiable. In combination with our new technique of sheath-to-enteric anastomosis, the patients considerably benefit from the preservation of liver parenchyma with low postoperative morbidity and very short in-hospital stay.

Alterations of tumor necrosis factor-alpha and interleukin 6 production and activity of the reticuloendothelial system in experimental obstructive jaundice in rats

BACKGROUND

Immunological changes are well recognised in obstructive jaundice. The aim of this study was to monitor plasma tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) levels in rats with obstructive jaundice.

METHODS

The ability of splenocytes and peritoneal exudate cells (PEC) to produce these cytokines both spontaneously and on induction with lipopolysaccharide (LPS), was compared in rats with and without obstructive jaundice (OJ). The activity of the reticuloendothelial system (RES) was also measured.

RESULTS

Serum cytokine levels in OJ rats were higher than in control rats. PEC cultures produced significantly more IL-6, compared with control rats, declining thereafter. TNF-alpha activity in the splenocyte cultures of OJ rats was also higher than in the control group. Pronounced differences were found in the ability to produce TNF-alpha by PEC, i.e., TNF-alpha production was much stronger on day 7 in OJ rats than in controls. On day 14 TNF-alpha production was much lower and the spontaneous response was equal to the LPS-induced one. On day 21 the cells of OJ rats partially regained the ability to produce TNF-alpha RES activity of OJ rats was significantly suppressed in the liver and spleen, whereas the phagocytic activity in the lungs was elevated.

CONCLUSION

We have demonstrated that the immune reactivity of OJ rats, initially elevated, underwent subsequent depression. The study also revealed a major effect of the operation alone on the studied parameters.

Translocação bacteriana para o pulmão na icterícia obstrutiva experimental em ratos

OBJETIVO: Tem sido demonstrado que a icterícia obstrutiva provoca depressão do sistema imunológico, mudança no padrão de colonização bacteriana dos intestinos e passagem de bactérias da luz intestinal para a circulação porta e sistêmica. Estudo experimental em ratos procurou observar a possibilidade de translocação bacteriana para os pulmões após a ligadura do colédoco. MÉTODO: Foram utilizados 20 ratos Wistar pesando de 178 a 215g, separados aleatoriamente em dois grupos iguais. Nos ratos do grupo I foi feita a ligadura do colédoco e nos do grupo II apenas a manipulação do colédoco com pinça atraumática (sham operation). No sétimo dia de observação os animais foram mortos com superdose de anestésico, sangue foi colhido para dosagem de bilirrubinas e os pulmões ressecados sob condições assépticas. Metade de cada pulmão foi homogeneizada e semeada em meios de cultura ágar McConkey e ágar sangue. A outra metade serviu para exame histopatológico -coloração hematoxilina e eosina. Os dados foram analisados pelo teste t, com significância 0,05. RESULTADOS: revelaram bilirrubina total em média 18,7±3,6 no grupo I e 0,7±0,2 no grupo II. No grupo I foram isoladas colônias de Klebsiela sp nos pulmões de 30% dos animais e E. coli em 20%, e os escores histopatológicos atingiram a média 6,2±2,08. No grupo II não foram detectadas bactérias nos pulmões e os escores do exame histopatológico atingiram 1,8±1,16. A diferença dos dados analisados mostrou-se significativa (p<0,05). CONCLUSÕES: Concluiu-se que a icterícia obstrutiva por ligadura do colédoco em ratos provocou translocação de germes Gram-negativos para os pulmões e resultou em alterações histopatológicas significativas.

Reticuloendothelial system blockade promotes progression from mild to severe acute pancreatitis in the opossum

OBJECTIVE

To examine the relation between hepatic reticuloendothelial system (RES) dysfunction and the development of acute biliary pancreatitis. In an opossum model, the authors tested the hypothesis that RES blockade can turn the mild pancreatitis seen after pancreatic duct obstruction (PDO) into the severe form.

SUMMARY BACKGROUND DATA

Biliary obstruction is considered the decisive event in gallstone pancreatitis. Suppression of the RES occurs during biliary obstruction.

METHODS

Eighteen opossums were placed into three groups of six animals each: group A, RES blockade with lambda-carrageenan; group B, PDO; and group C, PDO and RES blockade with carrageenan. The severity of pancreatitis was evaluated by enzyme serum levels and percentage of pancreatic tissue necrosis. RES capacity was measured by dynamic liver scintigraphy, and hepatic blood flow was documented using the hydrogen clearance technique.

RESULTS

No changes in hepatic blood flow occurred in groups A to C. RES capacity was suppressed in groups A and C; in group B, RES function remained unchanged. In group A, amylase and lipase levels remained normal, 3 +/- 1.9% of pancreatic tissue were necrotic. The animals in group B developed mild edematous pancreatitis with an increase in amylase and lipase levels and 15 +/- 10% of pancreatic necrosis. In group C, amylase and lipase increased significantly and histology revealed severe necrotizing pancreatitis, with 72 +/- 11% of necrotic areas.

CONCLUSIONS

Artificial RES blockade can promote the progression from mild pancreatitis as observed after PDO to the severe necrotizing form of the disease. Thus, RES dysfunction resulting from biliary obstruction might be an important cofactor in the pathogenesis of bile-induced pancreatitis.

Influência da icterícia obstrutiva na cicatrização da pele e de anastomose jejunal em ratos

A cicatrização da pele e do intestino podem ser influenciadas pela elevação da bilirrubina. Com o objetivo de avaliar o possível efeito da icterícia obstrutiva sobre a sutura da pele e de anastomose jejunal, foram estudados 32 ratos, divididos em quatro grupos (n=8) e acompanhados em períodos pós-operatórios de sete e 14 dias. Todos os animais foram submetidos a laparotomia e anastomose jejunal. Os grupos 1 e 2 serviram como controle dos grupos 3 e 4, os quais foram submetidos a ligadura do ducto biliopancreático. Os animais dos grupos 1 e 2 mantiveram o mesmo peso corporal durante todo o período de acompanhamento, enquanto os ictéricos apresentaram uma queda ponderal significativa após sete dias (p<0,05). Não houve diferença na resistência da sutura de pele entre os ratos ictéricos e não-ictéricos. Após duas semanas, a icterícia reduziu a resistência anastomótica jejunal (p<0,01). O exame histológico revelou menor grau de desenvolvimento da fibrose cicatricial nas anastomoses dos ratos ictéricos. Conclui-se que a icterícia obstrutiva pode atuar negativamente sobre a cicatrização tissular. Deve-se ressaltar a importância dos fatores associados à icterícia na gênese desse efeito.

Increased intestinal permeability and altered mucosal immunity in cholestatic jaundice

OBJECTIVE

To examine the effects of cholestatic jaundice on gut barrier function.

SUMMARY BACKGROUND DATA

Gut barrier failure occurs in animal models of jaundice. In humans, the presence of endotoxemia indirectly implicates failure of this host defense, but this has not previously been investigated in jaundiced patients.

METHODS

Twenty-seven patients with extrahepatic obstructive jaundice and 27 nonicteric subjects were studied. Intestinal permeability was measured using the lactulose-mannitol test. Small intestinal morphology and the presence of mucosal immunologic activation were examined in endoscopic biopsies of the second part of the duodenum. Systemic antiendotoxin core IgG antibodies and serum interleukin-6 and C-reactive protein were also quantified. Intestinal permeability was remeasured in 9 patients 5 weeks after internal biliary drainage.

RESULTS

The median lactulose-mannitol ratio was significantly increased in the jaundiced patients. This was accompanied by upregulation of HLA-DR expression on enterocytes and gut-associated lymphoid tissue, suggesting immune activation. A significant increase in the acute phase response and circulating antiendotoxin core antibodies was also observed in the jaundiced patients. After internal biliary drainage, intestinal permeability returned toward normal levels.

CONCLUSIONS

A reversible impairment in gut barrier function occurs in patients with cholestatic jaundice. Increased intestinal permeability is associated with local immune cell and enterocyte activation. In view of the role of gut defenses in the modern paradigm of sepsis, these data may directly identify an important underlying mechanism contributing to the high risk of sepsis in jaundiced patients.

Adverse metabolic and microbiological effects of tube feeding in experimental canine obstructive jaundice

BACKGROUND

Inadequate oral intake and poor absorption result in malnutrition in obstructive jaundice. Both malnutrition and obstructive jaundice promote bacterial translocation from the gut. This study was designed to test the efficacy of tube feeding in preventing malnutrition and in decreasing the metabolic and microbiological adverse effects in obstructive jaundice.

METHODS

Forty adult mongrel dogs were studied and were allocated into one of four groups: group I (PO-control) underwent sham ligation of the common bile duct (CBDL) and was fed ad libitum on Portagen (Mead Johnson, Evansville, IN); group II (PO-CBDL) underwent CBDL and was ad libitum fed on the same formula; group III (FEG-control) underwent sham CBDL and received forced esophagogastric feeding (FEG) with Portagen; and group IV (FEG-CBDL) underwent CBDL and received FEG. All the animals underwent insertion of a F-12 feeding tube to the stomach from an esophagotomy wound on day 1 and the tube was used for continuous enteral feeding with Portagen over 4 h/d from day 2 until day 13 in groups III and IV. Fourteen days later, blood samplings were done and a laparotomy was performed to obtain liver, mesenteric lymph nodes (MLN), and terminal ileum for quantitative bacterial culture. Bacterial translocation to MLN and liver was represented by log10 CFU/g of tissue in this study.

RESULTS

Both group II and IV animals with CBDL significantly lost body weight (p = .0001) and had a lower level of prealbumin (p = .0054). A significant increase in bacterial translocation to MLN and to liver occurred in groups II and IV (p = .0017 and .0268, respectively). Intestinal bacterial population was also higher in these two groups than in the other two controls (p = 0.0028). An increase in plasma ammonia level was found in dogs with CBDL (p = .0002) and in dogs with FEG (p = .003), compared with their respective controls. Three among 13 dogs in group IV died and no mortality occurred in the other groups (p = .223).

CONCLUSIONS

Tube feeding fails to improve malnutrition in obstructive jaundice and is associated with intestinal bacterial overgrowth, promoting bacterial translocation to MLN and liver, precipitating liver dysfunction and consequently a higher mortality.

Metabolic effect of parenteral nutrition in dogs with obstructive jaundice

OBJECTIVE

To assess the effect of total parenteral nutrition (TPN) on macronutrient metabolism in obstructive jaundice.

METHODS

Forty adult mongrel dogs were equally divided into four groups: group I (PO-control) received sham ligation of common bile duct (CBDL) and was fed dog chow and water ad libitum; group II (PO-CBDL) underwent CBDL and was fed dog chow; group III (TPN-control) received sham CBDL and TPN; and group IV (TPN-CBDL) underwent CBDL and received TPN. Blood chemistries, plasma amino acids and liver histologies were studied before (Day 1) and at the end (Day 14) of the experiment.

RESULTS

A significant elevation of bilirubin and alkaline phosphatase was observed in dogs with CBDL. Blood glucose was not changed significantly in any group. Significant increases in triglyceride and cholesterol were present in CBDL dogs. Significant differences in the concentrations of a few plasma amino acids, including an elevation of phenylalanine, were found in TPN dogs. A significant increase in aromatic amino acids (AAA) and a noticeable depression of the molar ratio of branched-chain amino acids (BCAA) to AAA was present in TPN-CBDL dogs, as was a significant increase in blood ammonia.

CONCLUSION

In the presence of obstructive jaundice, TPN does not significantly affect carbohydrate or lipid metabolism. However, a derangement in protein metabolism with the standard TPN solution in current use suggests that either a modification of amino acid composition or an increase in total energy to protein energy ratio in TPN solution may be necessary to obviate such a consequence.

Modulation of immune function and weight loss by L-arginine in obstructive jaundice in the rat

Jaundiced surgical patients have a high incidence of postoperative complications. Many causative factors have been identified including cachexia and immune suppression. The amino acid L-arginine has anabolic and immunostimulatory properties. It was hypothesized that dietary supplementation with L-arginine would diminish the weight loss and immune suppression of obstructive jaundice. Sixteen male Wistar rats rendered jaundiced by bile duct ligation were allocated to two groups. The test group (n = 8) received drinking water supplemented with 1.8 percent L-arginine ad libitum and the control group (n = 8) received a solution of isonitrogenous glycine. Both groups had free access to standard chow. Body-weight, and fluid and food intake were recorded. After 21 days, delayed-type hypersensitivity to 2,4-dinitrofluorobenzene was assessed. Animals receiving L-arginine consumed more food than controls (mean(s.e.m.) 414(16) versus 360(13) g, P < 0.05) and lost less weight (mean(s.e.m.) proportion of initial body-weight lost 7.8(1.2) versus 14.8(1.4) percent, P < 0.05). The delayed-type hypersensitivity response was significantly greater in rats receiving L-arginine (mean(s.e.m.) increase in ear thickness 23.9(2.7) versus 9.4(2.1) percent, P < 0.05). In this animal model of obstructive jaundice dietary supplementation with L-arginine diminished both weight loss and immune suppression.

Role of parenteral nutrition in preventing malnutrition and decreasing bacterial translocation to liver in obstructive jaundice

Surgery in patients with obstructive jaundice is associated with significant infectious complications probably due to impaired immune function and malnutrition. Total parenteral nutrition (TPN) may alleviate malnutrition but may also promote bacterial translocation (BT) from the gut. To elucidate if TPN can prevent malnutrition without promotion of BT in obstructive jaundice, 40 dogs underwent laparotomy for tissue sampling and placement of a central venous line and were allocated into one of four groups: I (PO-control) received dog chow and water ad libitum; II (PO-CBDL) underwent ligation of common bile duct (CBDL) and was fed dog chow; III (TPN-control) received TPN; and IV (TPN-CBDL) underwent CBDL and received TPN. Body weight, blood samples for liver function tests and bacterial culture, and tissues from liver and mesenteric lymph nodes (MLN) for quantitative bacterial culture and for histology were obtained prior to and 2 weeks after the experiment. The incidence of BT to MLN was 40% in the PO-CBDL and TPN-CBDL animals, which was significantly different from the other two groups (0%; p < 0.05). The incidence of BT to liver was 70% (7/10) in the PO-CBDL animals, which was significantly higher than that in groups I, III, and IV (0%, 20%, 20%, respectively) (p < 0.05). The PO-CBDL animals showed a significant decrease in body weight and prealbumin compatible with malnutrition, whereas the TPN-CBDL animals showed a significant increase in alkaline phosphatase and a consistent cholestasis on histology. The data suggest that TPN can prevent jaundice-associated malnutrition and decrease BT to liver but should be administered cautiously because it may precipitate cholestasis.

Biliary drainage in obstructive jaundice: experimental and clinical aspects

Jaundiced patients undergoing invasive diagnostic and therapeutic procedures are at increased risk of complications and death. Despite the large number of clinical and experimental investigations carried out to identify relevant risk factors, no single parameter has been found to be consistently useful in predicting morbidity or mortality. Biliary decompression was initially employed by surgeons and subsequently by interventional radiologists. More recently, endoscopic retrograde cholangiopancreatography has provided an alternative route for decompression of the biliary tree and preliminary data using this method are encouraging. Although there are enthusiastic proponents of various therapeutic techniques, controlled trials have not been convincing in highlighting the benefits of biliary drainage or in determining the best approach. This article reviews the literature pertaining to this complex surgical problem; an attempt has been made to balance the advantages and disadvantages of biliary decompression as palliation and/or preliminary treatment for extrahepatic biliary obstruction.

Modification of reticuloendothelial function by muramyl dipeptide-encapsulated liposomes in jaundiced rats treated with biliary decompression

Rats with 2 weeks of biliary obstruction, with and without 1 week of concomitant biliary decompression relieving the jaundice, were treated with physiologic saline, free muramyl dipeptide (MDP), placebo liposomes, or liposome-encapsulated MDP. Reticuloendothelial system (RES) function was evaluated by blood clearance of intravenously injected 125I-labelled Escherichia coli. The corrected phagocytic index (alpha) after 1 week of biliary decompression returned to normal levels in animals treated with MDP liposomes, whereas RES function was impaired (P < 0.05) in all other jaundiced and biliary-decompressed groups. In the biliary-decompressed, MDP-liposome-treated group, hepatic uptake of radiolabelled bacteria was significantly higher (P < 0.05) and renal entrapment of bacteria was significantly lower (P < 0.05) than in all other jaundiced and biliary-decompressed groups. We conclude that treatment with MDP liposomes improves the otherwise impaired RES function in rats with biliary obstruction and biliary decompression.

Effect of biliary decompression on reticuloendothelial function in jaundiced rats

The recovery of reticuloendothelial system (RES) function following decompression of obstructive jaundice was studied using a rat model with bile duct ligation and side-to-side choledochoduodenostomy. Histopathological changes in the liver were still present 5 weeks after relief of jaundice, while results of liver function tests had returned to normal. RES function evaluated by the blood clearance and organ uptake of radiolabelled Escherichia coli using a corrected phagocytic index gradually returned to normal following biliary decompression. The severely impaired RES activity noted 1 week after operation may explain the increased incidence of sepsis and renal insufficiency in the early period after biliary surgery in jaundiced patients.

Defective Fc receptor-mediated clearance in patients with primary biliary cirrhosis

Fc receptor-mediated clearance of immunoglobulin G-coated autologous erythrocytes was studied in patients with primary biliary cirrhosis (n = 14), alcoholic liver cirrhosis (n = 5) and healthy reference individuals (n = 14). The mean half-life of the sensitized erythrocytes was significantly prolonged in patients with primary biliary cirrhosis (85 +/- 25 minutes; P less than 0.001) compared with the corresponding value in patients with alcoholic cirrhosis (16 +/- 2 minutes) and healthy reference individuals (20 +/- 5 minutes), respectively. No correlation between clearance rate and age, liver histopathology, or serum levels of bilirubin, aminotransferases, immunoglobulin G, immunoglobulin A, and Clq binding or C3-containing immune complexes was found. The results presented here indicate a profound disturbance of Fc receptor-mediated immune clearance function in patients with primary biliary cirrhosis.

Altered lymphocyte subsets and natural killer cells of patients with obstructive jaundice in perioperative period

Sepsis is a common and occasionally lethal complication of obstructive jaundice. The reasons for the increased susceptibility to infection are not fully understood. This study was conducted to examine lymphocyte subsets and natural killer cells of patients with obstructive jaundice in perioperative period. In these patients, when compared with normal controls, there was a significant reduction in the percentage of Leu 4 (pan T lymphocytes), Leu 3a (T helper cells) and Leu 7 (natural killer cells) before operation, and the immune suppression induced by surgical operation was more marked and persistent.

Effects of relief of biliary obstruction on mononuclear phagocyte system function and cell mediated immunity

Obstructive jaundice causes depression of immune system function but it is unclear at present how rapidly immune function recovers after relief of biliary obstruction. To address this issue, we studied 218 Sprague-Dawley rats with common bile duct obstruction. Mononuclear phagocyte function, cell mediated immune function, portal-systemic shunt fraction, liver function tests, and liver histology were evaluated in normal (sham) rats, obstructed rats, and at weekly intervals after relief of biliary obstruction. Hepatic uptake of radiolabelled bacteria was 82 per cent in sham rats and 66 per cent in rats 21 days after CBD obstruction (P less than 0.05). Phagocytic activity returned to normal within 7 days after choledochoduodenostomy. Cell mediated immunity, measured by skin graft rejection, was significantly prolonged in the obstructed group (P less than 0.05) but had returned to normal 7 days after biliary diversion. Return of hepatocellular function, as measured by liver function tests, paralleled recovery of immune function. This study demonstrates prompt recovery of the immune system after internal biliary drainage for obstructive jaundice. This finding is in contrast to previous studies that demonstrated persistent immune suppression months after biliary diversion. These data may have implications concerning the usefulness of internal biliary drainage before surgery in patients with obstructive jaundice.

Impaired hepatic bacterial clearance is reversed by surgical relief of obstructive jaundice

Sepsis is a major cause of morbidity and mortality in infants with cholestatic jaundice. Previous studies have shown that biliary obstruction in rats causes a significant decrease in hepatic phagocytosis of viable Escherichia coli. This study tests this hypothesis and further evaluates whether the impaired function of the reticuloendothelial system of the liver (Kupffer cells) can be reversed by the relief of the biliary obstruction. Male Sprague-Dawley rats (weighing 140 to 150 g) were placed in three groups. Group I (n = 10) consisted of sham-operated controls. In Group II (n = 30), ligation and division of distal common bile duct (CDL) was performed. Group III (n = 30) underwent choledochoduodenostomy 2 weeks following ligation and division of common bile duct. At 1, 2, and 3 weeks following the operation, 10(9) 35S-radiolabeled viable E coli were injected intravenously via the tail vein. At 10 minutes, bacterial distribution in the liver, spleen, kidneys, and lungs was determined. Tissue samples (50 to 100 mg) from each organ were processed for liquid scintillation counting. The final distribution of bacteria was calculated from the input specific activity (dpm/bacteria) and expressed as the mean percentage of injected viable E coli per gram of tissue and per total organ weight. There was a significant decrease in the trapping of bacteria by the liver's Kupffer cells in rats in group II, at 2 and 3 weeks following CDL (45.0% +/- 14.0% and 15.1% +/- 4.9%, respectively, v controls 75.9% +/- 13.7%; P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)

Soluble interleukin-2 receptor and soluble CD8 in liver cirrhosis and obstructive jaundice

Activated lymphocytes secrete soluble interleukin-2 receptor (sIL-2R); CD8-positive lymphocytes secrete soluble CD8 (sCD8). Liver dysfunction in cirrhosis and obstructive jaundice is known to result in depressed cellular immunity. To evaluate whether this is due to real inactivation of the immune system, we measured sIL-2R and sCD8 in the serum of 46 patients with liver cirrhosis, 25 patients with obstructive jaundice, 32 patients with alcoholic liver disease without evidence of cirrhosis, 23 healthy persons and 43 patients with unrelated disease. sIL-2R in patients with cirrhosis (mean +/- s.e.m. 1499 +/- 140 U/ml) and obstructive jaundice (1517 +/- 204) was significantly increased compared with healthy subjects (363 +/- 29) and patients with unrelated diseases (685 +/- 92); sCD8 was significantly increased in patients with cirrhosis (737 +/- 63) but not in patients with obstructive jaundice (419 +/- 32) compared with healthy subjects (322 +/- 23) and patients with unrelated diseases (375 +/- 22). No difference was found between patients with cirrhosis due to alcohol abuse (n = 15) and chronic hepatitis B (n = 6). The Child-Pugh score had no significant influence on the sIL-2R or sCD8 value. In obstructive jaundice, sIL-2R correlated with alkaline phosphatase as marker of cholestasis (r = 0.43). These data show that in spite of the apparent depressed cellular immune defense both in liver cirrhosis and obstructive jaundice there is a general activation of the immune system but the CD8+ cell compartment is only activated in liver cirrhosis. The great changes of sIL-2R and sCD8 in liver dysfunction are important for the interpretation of studies using these serum proteins as markers for immune activation.

A potential basis for suppressed inflammatory cell function in pediatric cholestatic hosts

Infective mortality is common in children who have hepatic failure. We have demonstrated that experimental hepatic failure (EHF) profoundly suppresses T cell function in vivo. To determine the basis for immune suppression in EHF we postulated that this phenomenon is attributable to alterations in accessory macrophage (Ma) function, T cell subsets, interleukin-2 (IL-2) production, or serum inhibition. Wistar Furth rats (200 g) were randomized to EHF (n = 23), Sham (n = 23), and normal control (NC) (n = 23) groups. On day 21, splenocytes and sera were harvested and immune assays performed in vitro. Following are the results (mean +/- SEM; Student's t test). Serum bilirubin was elevated in EHF versus Sham and NC groups (P less than .01). EHF splenic macrophages suppressed PHA when added to microcultures at 10(5) concentration (-140 +/- 550 v 12,263 +/- 2,492 [Sham] and 21,413 +/- 1,702 [NC] P less than .01). This effect was not evident when macrophages were added back to microcultures at 10(3) and 10(4) concentrations, suggesting a dose-dependent inhibitory effect. T helper: suppressor ratios did not differ in EHF (1.3 +/- 0.2) compared with Sham (1.4 +/- 0.2) and NC groups (1.2 +/- 0.1). IL-2 production was similar in EHF, Sham, and NC animals (112,141 +/- 5,232 versus 106,691 +/- 1,419 and 120,759 +/- 3,249 counts per minute). T cell inhibitory activity was not demonstrable in EHF sera. These data show that splenic macrophages can inhibit T cell function in vitro. This phenomenon may be paramount in predisposing children with liver disease to infection.

Profound suppression of lymphocyte function in early biliary obstruction

The blastogenic response to mitogens was studied in spleen and lymph node cells from four groups of Lewis rats at 1 to 2, 3 to 5, 6 to 9 and 10 to 14 days, respectively, after common bile duct ligation (CBD) or sham celiotomy (SC). Suppression in the splenocytes' mitogenic response to concanavalin A and phytohemagglutinin was noted as early as 3 days after common bile duct ligation. The response remained suppressed during the period of observation. Lymph node cells manifested a suppressed response to concanavalin A and phytohemagglutinin after 4 days of jaundice. No alteration in splenocyte response to lipopolysaccharide was observed. There was no correlation with the level of serum bilirubin.

Impaired specific cell-mediated immunity in experimental biliary obstruction and its reversibility by internal biliary drainage

Little is known of the effect of cholestasis on host immunity. This study evaluates lymphocytic responsiveness to PHA and LPS mitogen and to allogeneic F344 antigen in Sprague-Dawley rats 21 days following bile duct ligation and 31 days following relief of jaundice by internal biliary drainage. Serum bilirubin level was significantly elevated in the bile duct ligated animals at Day 21 (P less than 0.001) and thereafter returned to preoperative levels following internal biliary drainage. Results demonstrate depressed responsiveness to PHA (P less than 0.001) and allogeneic F344 antigen in vivo (P less than 0.04) and in vitro (P less than 0.02) in bile duct ligated animals as compared to sham, sham pair-fed, and normal control rats. The observed deficiency in responsiveness to T-cell-dependent mitogen and antigen cannot be explained on the basis of complicating nutritional, renal, or infective factors. Subsequent internal biliary drainage results in some improvement in T-cell responsiveness in the bile duct ligated group although recovery is not complete. B-Lymphocytic response to LPS mitogen is not affected by bile duct ligation. We conclude that cholestasis subsequent to extrahepatic biliary obstruction per se results in impairment of cell-mediated immunity in vivo. This impairment is partly reversible by internal biliary drainage. In vitro B-cell function does not appear to be affected in this model. Further study of impaired cell-mediated immunity in extrahepatic biliary obstruction will improve our understanding of the immunological status of patients with obstructive jaundice and cholestatic liver diseases.