Neutrophil chemotaxis in bile duct-obstructed rats,and effect of internal biliary drainage

BACKGROUND/AIMS: Our previous studies demonstrated enhanced neutrophil chemotaxis in bile duct-ligated, obstructive jaundice rats. In the present study, we produced a reversible obstructive jaundice model in rats. The efficacy of the present model in producing sufficient bile flow blockade and subsequent internal biliary drainage was assessed. Furthermore, the effect of internal biliary drainage on neutrophil chemotaxis was evaluated. METHODOLOGY: Bile duct was obstructed with a polyester tape attached with a stainless steel coil. Internal biliary drainage was performed by removing the tape. Rats were subjected to either 10 days' bile duct obstruction or 4 days' bile duct obstruction followed by 6 days' internal biliary drainage. Some animals underwent conventional bile duct ligation and dissection for 4 or 10 days. Neutrophil chemotaxis was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-beta) as chemoattractant. RESULTS: The present technique produced sufficient obstructive jaundice as evidenced by increases in serum alanine aminotransferase and total bilirubin throughout the observation period, the values of which were insignificant with those induced by the conventional method. Internal biliary drainage effectively normalized these values. Similarly, neutrophil chemotaxis was enhanced with both procedures, and increased neutrophil chemotaxis was significantly decreased after drainage. CONCLUSIONS: The present reversible obstructive jaundice method is as efficacious as the conventional method for producing obstructive jaundice, and internal biliary drainage could be readily available. With the present model, neutrophil overactivity in obstructive jaundice was effectively alleviated by internal biliary drainage. The result may support the role of preoperative biliary drainage in the prevention of postoperative septic complications.     

Increased neutrophil chemotaxis in obstructive jaundice: An in vitro experiment in rats

BACKGROUND AND AIMS: Changes in neutrophil functions in obstructive jaundice have been poorly understood. An in vitro experimental study was performed to evaluate the effect of obstructive jaundice on the functions of macrophages (secretion of neutrophil chemoattractants) and neutrophils (chemotaxis and superoxide anion generation). METHODS: Obstructive jaundice was produced in rats by 7 day bile duct ligation. Peripheral neutrophils and peritoneal macrophages were harvested from either normal, sham-ligated or bile duct-ligated rats and supernatants of the monolayers of the respective macrophages were prepared after stimulation with lipopolysaccharide. Neutrophil chemotaxis was evaluated with a modified Boyden method. RESULTS: The supernatant of the bile duct-ligated rat macrophages showed a chemotactic effect on normal rat neutrophils with insignificant difference from the supernatant of the sham-ligated rat macrophages. Chemotaxis of the bile duct-ligated rat neutrophils towards the supernatant of the normal rat macrophages was significantly increased, compared with that of sham-ligated rat neutrophils. Similarly, neutrophils from bile duct-ligated rats showed significantly greater chemotaxis to formyl-methionyl-leucyl-phenylalanine than the sham-ligated rat neutrophils. Superoxide anion generation in response to formyl-methionyl-leucyl-phenylalanine or phorbol myristate acetate was significantly increased in the bile duct-ligated rats compared with the sham-ligated rats. CONCLUSIONS: The results suggest that the neutrophil is primed in terms of chemotaxis and superoxide anion generation in obstructive jaundice. How these activated neutrophils play a role in the inflammatory response to obstructive jaundice should be evaluated.     

Effects of sera from patients with obstructive jaundice on the generation of oxygen intermediates by normal polymorphonuclear leukocytes

Recently it has been suggested that oxygen intermediates play an important role in the pathogenesis of tissue damage. The effect of sera from patients with obstructive jaundice on the generation of oxygen intermediates by normal polymorphonuclear leukocytes (PMNs) was investigated. Sera from patients with obstructive jaundice increased superoxide anion (O2-), hydrogen peroxide (H2O2) and hydroxol radical (OH.) generation compared with sera from healthy individuals or patients with biliary tract stones and/or tumors of the biliary tract or pancreas (without obstructive jaundice). In particular, the hydroxyl radical, which is one of the most potent oxidants capable of causing tissue damage, was produced in large quantities. Sera from patients with obstructive jaundice have a strong capacity to induce production of oxygen intermediates from PMNs, and oxygen intermediates may play a role in the pathogenesis of hepatic and other organ injury in obstructive jaundice.     

Effects of obstructive jaundice on neutrophil production and acquisition of chemotactic activity in the bone marrow

Background and Aims:  Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats.
Methods:  Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-β) as a chemoattractant.
Results:  Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage.
Conclusion:  The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.     

Effects of obstructive jaundice on neutrophil production and acquisition of chemotactic activity in the bone marrow

BACKGROUND AND AIMS: Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats. METHODS: Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-beta) as a chemoattractant. RESULTS: Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage. CONCLUSION: The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.     

Perioperative hepatic functional risk assessed with technetium-99m diethylenetriamine pentaacetic acid-galactosyl human serum albumin liver scintigraphy in patients undergoing pancreaticoduodenectomy complicated by obstructive jaundice.

CONCLUSION: Liver scintigraphy with technetium-99m diethylenetriamine pentaacetic acid-galactosyl human serum albumin (Tc-GSA) can be used to predict outcome of biliary drainage and hepatic function after pancreaticoduodenectomy in patients with pancreatic, biliary, and ampullary carcinomas complicated by obstructive jaundice. BACKGROUND: Preoperative obstructive jaundice has been reported as a crucial risk factor for serious postoperative complications in patients undergoing pancreaticoduodenectomy. The aim of the present study was to investigate whether Tc-GSA liver scintigraphy can assess hepatic functional risk in patients with pancreatic, biliary, and ampullary carcinomas complicated by obstructive jaundice. METHODS: Liver scintigraphy was performed before biliary drainage in 18 patients with obstructive jaundice. The maximum removal rate of Tc-GSA (GSA-Rmax; standard normal value > or = 0.60) was calculated. These patients underwent pancreaticoduodenectomy with wide lymphadenectomy. The efficacy of preoperative biliary drainage was assessed with the decrease in serum bilirubin concentration in the first week after biliary drainage. Postoperative liver function was assessed with the increase in serum bilirubin concentration, which was the difference between the immediate preoperative and maximal postoperative bilirubin concentrations. RESULTS: Serum bilirubin decreased more in the first week after biliary drainage in patients with GSA-Rmax > or = 0.60 (7.64 +/- 1.09 mg/Dl/wk) than in patients with GSA-Rmax < 0.60 (3.56 +/- 1.25 mg/DL/wk, p = 0.042). Postoperative bilirubin increased less in patients with GSA-Rmax > or = 0.60 (0.81 +/- 0.30 mg/dL) than in patients with GSA-Rmax < 0.60 (4.00 +/- 0.69 mg/DL, p = 0.0012). Multivariate analysis showed that GSA-Rmax significantly predicted the postoperative bilirubin increase (p = 0.020).     

Neuropeptides and inflammation. A somatostatin analog as a selective antagonist of neutrophil activation by substance P.

OBJECTIVE. Substance P and somatostatin are neuropeptides found in peripheral sensory nerves. In vitro, these have opposing effects on inflammatory cells. We compared the effects of these peptides on the activation of neutrophils. METHODS. Neutrophils were isolated from healthy volunteers, and chemotaxis, superoxide anion generation, aggregation, and changes in cytosolic calcium and GTPase activity were measured in the presence of substance P, somatostatin, and the chemoattractant FMLP. RESULTS. Substance P was an effective chemoattractant, 20% as potent as FMLP at equimolar concentrations. Substance P also stimulated GTPase activity in neutrophil plasma membranes. Somatostatin did not activate neutrophils; however, it effectively inhibited neutrophil chemotaxis and GTPase activity provoked by substance P, but not by FMLP. CONCLUSIONS. These studies demonstrate that substance P can effectively stimulate chemotaxis, possibly via effects on a GTP-binding protein distinct from that triggered by FMLP, and that somatostatin is a selective antagonist of substance P. The biochemical specificities of these peptides on cells may modulate neurogenic inflammation at the local level.     

Endotoxin, cytokines, and endotoxin binding proteins in obstructive jaundice and after preoperative biliary drainage

BACKGROUND: Obstructive jaundice is associated with postoperative complications related to increased endotoxaemia and the inflammatory response. In animals obstructive jaundice is associated with endotoxaemia and cytokine induction, which are reversed by internal biliary drainage. AIMS: To study endotoxaemia and the subsequent inflammatory response in obstructive jaundiced patients and after endoscopic biliary drainage. METHODS: In 15 patients with malignant distal obstructive jaundice, inflammatory and bacteriological parameters were assessed before endoscopic stent placement and after three weeks endoscopic drainage. RESULTS: Drainage reduced bilirubin from 252.5 to 45.1 micromol/l. At baseline low level endotoxaemia was detected (4.3 pg/ml) which was not affected after drainage (4.5 pg/ml). Serum interleukin 8 (IL-8) and endotoxin binding proteins were increased in jaundice and reduced after drainage (IL-8 113.6 to 20.7 pg/ml; lipopolysaccharide binding protein 24.2 to 16.5 microg/ml; sCD14 17.4 to 7.6 microg/ml; bactericidal/permeability increasing protein 2.9 to 1.8 ng/ml). Levels of other cytokines, augmented in animals, were only slightly increased and not changed after drainage (tumour necrosis factor (TNF): 21.7 and 18.4 pg/ml; sTNFr p55/75: 2.9/7.0 and 2.7/5.6 ng/ml; IL-6: 4.2 and 6.1 pg/ml; IL-10: 4.5 and 2.7 pg/ml). Elastase and lactoferrin tended towards reduction after drainage. All bile cultures were positive after stenting. CONCLUSIONS: The effects of obstructive jaundice in humans on endotoxin and cytokines are different from those in animal models. Obstructive jaundice causes alterations in circulating endotoxin binding proteins and IL-8. Concentrations of other mediators (TNF, previously suggested as being responsible for systemic endotoxaemia effects) are low and not affected by drainage.     

Serum endothelin-1 and hepatocyte growth factor levels in patients with obstructive jaundice.

BACKGROUND/AIMS: Endothelin-1, a potent vasoconstrictive peptide, is known to modulate changes in local circulation. Additionally, hepatocyte growth factor, a potent mitogen for hepatocytes, is increased in various liver diseases. The present study examined changes in serum endothelin-1 and hepatocyte growth factor levels in patients with obstructive jaundice before and after percutaneous transhepatic cholangio drainage. METHODOLOGY: Endothelin-1 and hepatocyte growth factor levels were measured by enzyme-linked immunosorbent assay using sera from 16 patients with obstructive jaundice before and after percutaneous transhepatic cholangio drainage. RESULTS: Serum endothelin-1 levels decreased rapidly in the good bilirubin decrease group after biliary drainage. Endothelin-1 levels decreased 1 week after drainage but then increased gradually in the worse bilirubin decrease group. Serum hepatocyte growth factor levels decreased gradually after biliary drainage, and were higher in the worse bilirubin decrease group than in the good bilirubin decrease group throughout the study. CONCLUSIONS: These results suggest that endothelin-1 may be associated with the microcirculatory disturbance in obstructive jaundice and prolonged cholestasis. Measurement of hepatocyte growth factor levels in patients with obstructive jaundice before percutaneous transhepatic cholangio drainage may be an early clinical predictor of the subsequent rate of decrease of the serum bilirubin concentration.     

Effect of percutaneous biliary drainage on serum levels of tumor markers in patients with obstructive jaundice

BACKGROUND/AIMS: Some tumor markers such as CA 19-9 are shown to be increased in obstructive jaundice due to either benign or malignant causes. In this study the clinical importance of raised serum levels of tumor markers have been evaluated, with particular reference to obstructive jaundice and percutaneous biliary drainage. METHODOLOGY: We conducted a prospective longitudinal before-after trial. Twenty-one patients with obstructive jaundice were investigated, 5 with benign obstruction and 16 with malignant disease. All patients were examined with abdominal CT prior to biliary drainage. All patients underwent percutaneous transhepatic cholangiography, and 20 of 21 patients underwent percutaneous biliary drainage within 3 days after the CT examination. RESULTS: The mean CA 19-9 at presentation was lower in the group with benign disease (95 +/- 60.9 IU/mL) than those with malignancy (461.9 +/- 331.4 IU/mL). The mean CA 19-9 level in the benign group 1 week after drainage was 12 +/- 11.8 IU/mL. The mean CA 19-9 level in the malignant group after drainage was 249.7 +/- 279.5 IU/mL. CONCLUSIONS: A prominently high serum CA 19-9 level at the presentation and a high serum CA 19-9 level after successful biliary drainage should prompt investigation for a malignant etiology of obstructive jaundice.     

The redox tolerance test as a measure of hepatic function in patients with obstructive jaundice

The redox tolerance test was performed before percutaneous transhepatic biliary drainage, in 15 patients with obstructive jaundice, and repeated 2 weeks after. Four patients without jaundice were evaluated as a control group. No difference was found in the redox tolerance index between the controls and the group with good bilirubin clearance. On the contrary, the redox tolerance index was significantly lower in the group with poor bilirubin clearance. No significant change in the redox tolerance index was revealed after percutaneous drainage. However, of four patients whose indices were smaller than 0.5 before biliary drainage, three died after developing cholangitis. The redox tolerance test is useful for evaluating hepatic function and predicting outcome in patients with obstructive jaundice.     

经内镜鼻胆管引流术与经内镜胆道支架置入术在低位恶性梗阻性黄疸术前胆道引流效果比较的Meta分析

目的比较经内镜鼻胆管引流术(ENBD)和经内镜胆道支架置入术(EBS)在低位恶性梗阻性黄疸术前胆道引流中的有效性及安全性。方法在中英文数据库中检索从建库至2020年8月发表的有关ENBD与EBS在低位恶性梗阻性黄疸术前胆道引流疗效对照研究的所有中英文文献,对纳入的研究进行质量评价和数据提取后,采用RevMan 5.3软件进行Meta分析,比较ENBD与EBS术前胆管炎发生率、术前胰腺炎发生率、支架障碍率、术前术后总并发症发生率、术后胰漏率的差异。结果最终纳入6项研究,包括1182例患者。Meta分析结果显示,在术前胰腺炎发生率、支架障碍率、术前术后总并发症发生率方面,ENBD组与EBS组比较差异均无统计学意义(OR分别为0.66、1.14、0.69,95%CI分别为0.44~0.99、0.56~2.31、0.41~1.15,P值分别为0.05、0.72、0.15)。但是,ENBD组相较于EBS降低了术前胆管炎发生率和术后胰漏率,差异均有统计学意义(OR分别为0.34、0.53,95%CI分别为0.23~0.50、0.32~0.88,P值分别为<0.00001、0.01)。结论对于诊断明确的低位恶性胆道梗阻患者,术前胆道引流使用ENBD优于使用EBS。未来需要更多的多中心大样本随机对照试验来验证这一结论。     

The prostaglandin paradox: additive inhibition of neutrophil function by aspirin-like drugs and the prostaglandin E1 analog misoprostol.

Nonsteroidal antiinflammatory drugs (NSAID) are thought to act in part by inhibiting prostaglandin H (PGH) synthase which diminishes release of inflammatory prostaglandins (PG). Paradoxically, PG of the E series also have antiinflammatory properties. We therefore studied the combined effects of NSAID and PGE1 on neutrophil activation. Incubation of neutrophils with a PGE1 analog, misoprostol (miso; 1 microM; 5 min, 37 degrees), reduced superoxide anion generation in response to the chemoattractant fmet-leu-phe (FMLP) to 70.7 +/- 7% of control (p less than 0.01). Piroxicam (10 microM) independently reduced FMLP dependent superoxide anion generation to 63.7 +/- 7.4% (p less than 0.01) of control. Addition of miso to piroxicam reduced superoxide anion production to 37.4 +/- 1.9%, an inhibition that exceeded that observed with either drug alone. Similarly, the addition of miso enhanced the inhibitory effects of indomethacin and sodium salicylate on superoxide anion generation, and of all 3 NSAID on other neutrophil functions (degranulation, aggregation and global rises in cytosolic calcium). Miso (1 microM) and NSAID, alone or in combination, did not inhibit superoxide anion generation in response to the calcium ionophore A23187 or phorbol myristate acetate, agents that bypass G protein depending signaling pathways, and that do not induce a rise in cytosolic cyclic AMP (cAMP). Therefore, our data clearly show that miso at micromolar concentrations, augments the inhibitory effects of NSAID on neutrophil activation via a mechanism dependent upon signal transduction across the plasma membrane.     

Neuropeptides and inflammation. A somatostatin analog as a selective antagonist of neutrophil activation by substance P

Objective. Substance P and somatostatin are neuropeptides found in peripheral sensory nerves. In vitro, these have opposing effects on inflammatory cells. We compared the effects of these peptides on the activation of neutrophils. Methods. Neutrophils were isolated from healthy volunteers, and chemotaxis, superoxide anion generation, aggregation, and changes in cytosolic calcium and GTPase activity were measured in the presence of substance P, somatostatin, and the chemoattractant FMLP. Results. Substance P was an effective chemoattractant, 20% as potent as FMLP at equimolar concentrations. Substance P also stimulated GTPase activity in neutrophil plasma membranes. Somatostatin did not activate neutrophils; however, it effectively inhibited neutrophil chemotaxis and GTPase activity provoked substance P, but not by FMLP. Conclusions. These studies demonstrate that substance P can effectively stimulate chemotaxis, possible via effects on a GTP-binding protein distinct from that triggered by FMLP, and that somatostatin is a selective antagonist of substance P. The biochemical specificities of these peptides on cells may modulate neurogenic inflammation at the local level.     

Neutrophils superoxide anion generation during carvedilol therapy in patients with stable angina

Neutrophil superoxide anion (O(2)(*-)) generation was measured during carvedilol therapy in patients with stable angina. The carvedilol group comprised 27 patients (18 men and 9 women), aged 38-51 years (mean 47.6 years) with stable angina. Carvedilol was administered in increased every 4-week doses: 12.5, 25 and 50 mg/24 h, respectively. The control group included 12 healthy subjects, aged 39-49 years (mean 45.7 years) with no drug administered. Blood samples were collected from cubital vein before and 4, 8 and 12 weeks after the therapy and once in the control group. Neutrophil O(2)(*-) generation was determined in whole blood without and with opsonized zymosan (OZ) stimulation according to Bellavite et al. method using superoxide dismutase from bovine erythrocytes. O(2)(*-) generation by nonstimulated and OZ-stimulated neutrophils was significantly higher (p<0.05) in patients with stable angina than in the control group. In carvedilol group, statistically significant (p<0.05) decrease in superoxide anion generation by nonstimulated and OZ-stimulated neutrophils was observed 8 and 12 weeks after the therapy and it did not differ from that in healthy subjects. Carvedilol has been shown to inhibit neutrophil O(2)(*-) generation in patients with stable angina.     

Hepatic functional evaluation using the galactose tolerance test in patients with obstructive jaundice

Hepatic functional mass was evaluated in patients with obstructive jaundice using the galactose tolerance test (GaTT), which reflected cytosolic function of hepatocyte. The T-1/2 values as an index on the GaTT were significantly prolonged in patients with obstructive jaundice in comparison with control subjects whether before or after percutaneous transhepatic biliary drainage (PTBD). But in each cases, some showed nearly normal GaTT-T/2 value and others showed severely prolonged value. Patients with obstructive jaundice could be divided into two groups according to the GaTT-T/2 value before PTBD. The decreasing rate of serum bilirubin level "b" after PTBD was significantly fair in the group A patients (good GaTT-T/2 value before PTBD) than the group B (poor GaTT-T/2 value before PTBD) (P less than 0.05). It was that GaTT-T/2 before PTBD which represented hepatic cytosolic functional mass could predict the effect of PTBD in patients with obstructive jaundice.     

Palliation for Extrahepatic Biliary Obstruction by Metastatic Colorectal Carcinoma

Objectives: Extrahepatic biliary obstruction due to metastatic colorectal carcinoma, though rare, can account for the occurrence of obstructive jaundice even in the presence of hepatic metastases. The present report aims at reviewing our experience with the palliative treatment of these patients. Methods: During a 5-yr period, 11 patients with obstructive jaundice had documented extrahepatic biliary obstruction secondary to metastatic colorectal carcinoma. Their clinical records were retrospectively analyzed. Results: Nonoperative drainage was performed in eight patients by either the endoscopic (n = 5) or percutaneous (n = 3) route. Palliation was achieved in six patients with a mean hospital stay of 24.5 days (14 % of survival). Three patients died of hepatorenai failure before a drainage procedure could be performed. Blocked stent and cholangitis were noted in two patients. The mean survival was 5 months in the drainage group. Conctusions: The occurrence of obstructive jaundice in patients with metastatic colorectal carcinoma deserves routine investigation to exclude extrahepatic biliary obstruction. Endoprosthesis insertion by nonoperative means should be considered for palliation.     

Effects of recombinant human granulocyte colony-stimulating factor on neutrophil function in normal rats.

We studied the effects of recombinant human granulocyte colony-stimulating factor (rG-CSF) on neutrophil functions in vitro using neutrophils isolated from the venous blood of normal rats. FMLP-induced superoxide anion (O2-) release, phagocytosis, and FMLP-induced chemotaxis were evaluated. These functions were significantly enhanced by rG-CSF treatment. In addition to performing neutrophil function assays, we evaluated FMLP binding to rat neutrophils after rG-CSF treatment. FMLP specific binding was not changed by rG-CSF treatment. In addition, we intravenously injected rG-CSF (10 micrograms/kg) or control vehicle into rats for 7 consecutive days, and evaluated the functions of neutrophils isolated from venous blood at 6 h after the final injection. The neutrophil count in the peripheral blood of rG-CSF-treated rats was increased significantly compared with that in control rats. FMLP-induced O2- release, phagocytosis, FMLP-induced chemotaxis and spontaneous migration of rG-CSF-treated neutrophils were significantly enhanced in comparison with those in control rats. These findings demonstrate that rG-CSF not only increases neutrophil counts in peripheral blood, but that it also enhances neutrophil functions, both in vitro and in vivo.     

Superoxide and nitric oxide production by Kupffer cells in rats with obstructive jaundice: effect of internal and external drainage

BACKGROUND AND AIMS: The role of Kupffer cells in obstructive jaundice (OJ) has not been fully understood. The aims of the present study were to measure superoxide and nitric oxide (NO) production by Kupffer cells in experimental OJ in rats and to investigate the response to internal and external biliary drainage. METHODS: Eighty male Sprague-Dawley rats were assigned to four groups: sham operation, OJ, and internal and external biliary drainage. Kupffer cells were isolated on day 7 in the sham operation and OJ group, and on day 7 after drainage procedures. Cells were cultured with or without lipopolysaccharide (LPS). Superoxide production was quantified in cultured Kupffer cells at 2 h and 48 h, respectively, after cell isolation using the superoxide dismutase inhibitable ferricytochrome c reduction method. Nitrite production in cell culture supernatants was measured 48 h later using Greiss reagents. RESULTS: Without LPS stimulation, Kupffer cells produced comparable superoxide and nitrite in each group (P > 0.05). With LPS stimulation, Kupffer cells in the OJ group produced significantly higher superoxide anions than the other groups (P = 0.006). Nitrite production was significantly increased in the OJ group and external biliary drainage group compared to rats in the sham operation and internal drainage groups (P < 0.01). CONCLUSIONS: Kupffer cells from rats with OJ produce great amounts of endotoxin-mediated oxidants. Both internal and external biliary drainage can decrease the elevated superoxide production. Internal drainage is superior to external drainage for reversing the distortional capacity of NO production by Kupffer cells.     

In vitro inhibition of interleukin-2-induced defective polymorphonuclear chemotaxis by TNF inhibitor

Abstract: Patients undergoing immunotherapy with interleukin-2 experience multiple side effects and are highly susceptible to bacteremia. In a previous study, we confirmed that a profound deficiency of neutrophil chemotaxis is induced by interleukin-2 therapy. Migration in response to N-formyl-methionyl-leucyl-phenylalanine (FMLP), being normal before therapy, was markedly impaired after the first cycle and further decreased after the third cycle of treatment. A direct effect of interleukin-2 on neutrophil chemotaxis is controversial. However, peripheral blood cells exposed to interleukin-2 secrete secondary cytokines. In particular, the release of tumor necrosis factor after interleukin-2 injection has been proposed as an important regulatory mechanism. When testing random migration and chemotaxis of neutrophils from normal subjects after incubation with the serum from treated patients, we found that this serum induced a defective chemotaxis similar to that of neutrophils from interleukin-2-treated patients. In order to assess the influence of tumor necrosis factor, we tested the effect of anti-tumor necrosis factor-alpha antibody on the chemotactic response of cells after incubation with the serum, and we observed a dose-dependent reduction of neutrophil chemotaxis deficiency. These data suggest that TNF is counteracting the neutrophil chemotactic deficiency observed during IL-2 treatment.