Objective To investigate the protective effects of antitumor necrosis factor-α antibody （TNF-αAb） on lung injury after cardiopulmonary bypass （CPB） and their mechanisms. Methods Forty healthy New Zealand white rabbits，weighting 2.0-2.5 kg，male or female，were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ，the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ，the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ，the rabbits received CPB only. In group Ⅳ，the rabbits only received sham surgery. Neutrophils count，TNF-α and malondialdehyde （MDA） concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content，TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ，after CPB，the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count，TNF-α and MDA（P＜0.05），higherTNF-α mRNA expression，apoptosis index and water content of the lung tissues （P＜0.05），and significantly lower oxyg-enation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ，after CPB，the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α （5 minutes after aortic declamping，220.43±16.44 pg/ml vs.185.27±11.78 pg/ml，P＜0.05；249.99±14.09 pg/ml vs.185.27±11.78 pg/ml，P＜0.05），significantly higher apoptosis index （at the time of CPB termination，60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），significantly higher blood levels of neutrophils count and MDA （P＜0.05），significantly higher TNF-α mRNA expression and water content of the lung tissues （P＜0.05），and significantly loweroxygenation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ，rabbits in group Ⅲ had significantly higher above parameters （P＜0.05） but lower oxygenation index （P＜0.05） only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.
Objective To examine the levels of interferon-gamma; (INF-gamma;), tumor necrosis factor-alpha; (TNF-alpha;) and interleukin-6(IL-6) in serum of patients with acute uveitis before and after treatment, and to explore the possible roles of those cytokines in the initiation and progression of the uveitis. Methods A series of 75 patients with acute uveitis,and 30 healthy persons from our hospital were investigated. The levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase and convalescent phase were measured by the enzymelinked immunosorbent assay. Result The serum levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase were significantly higher than that of the convalescent phase and the healthy controls (F=65.805/50.418/155.381, P=0.000). A significant negative correlation was found between the serum levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase with their initial visual acuity(r=-0.656, -0.592 and -0.653, Plt;0.01). There was also a positive correlation among the serum levels of INF-gamma;, TNF-alpha; and IL-6(r=0.340, 0.467 and 0.338, Plt;0.05). Conclusions There are high serum levels of INF-gamma;, TNF-alpha; and IL-6 in patients with acute uveitis, and the cytokines levels were decreased after the treatment. The results suggested that the INF-gamma;, TNF-alpha; and IL-6 involved in initiation and progression of uveitis.
Objective To observe the histopathologic features and expression patterns of tumor necrosis factor-alpha; （TNF-alpha;）, interleukin-1beta;（IL-1beta;） and Escherichia coli lipopolysaccharide (LPS) in the rat vitreous with LPS inducedendophthalmitis. Methods Wistar rats were randomly divided into saline control group (SC,136 rats）,endophthalmitis group （EO, 168 rats）and blank control group （BC,12 rats）.EO group received an intravitreal injection of 5 mu;l LPS; SC group received 5 mu;l sterile saline and no intervention for BC group.Six,12,24,48, and 72 hours,5 and 7 days after injection, intraocular inflammation were observed and the eyes and vitreous were collected for histopathological examination and measurement of TNF-alpha;, IL-1beta; and LPS expression. Results Severe inflammatory responses in the eyes were observed in EO group between six and 72 hours after LPS injection，ocular inflammation subsided seven days after LPS injection. In the vitreous, a peak neutrophil count was observed at 24 hours （1224.64plusmn;132.2） cells/eye that rapidly declined at 72 hours （342.25plusmn;47.7） cells/eye. The levels of TNF-alpha; and IL-1beta; in EO group were peaked at 24 hours with （996.18plusmn;89.45） and（5556plusmn;1440）pg/ L, respectively；Persisted at 48 hours and began to decline rapidly thereafter. Seven days after LPS injection, levels of TNF-alpha; and IL-1beta; returned to baseline with （22.16plusmn;5.84）and （73.7plusmn;18.7） pg/L, respectively. LPS concentration in EO group decrease rapidly at 72 hours with （11.03plusmn;3.41） ng and disappear on days 7 with (0.22plusmn;0.08) ng after LPS injection.Conclusions Massive neutrophils infiltration, high levels expression of TNF-alpha; and IL-1beta; and spontaneous elimination of bacterial elements in vitreous cavity were major pathologic characteristics in this experimental model. The expression patterns of TNF-alpha;,IL-1beta; were in accord with LPS clearance process.
Objective To detect the effects of cytokines on the expression of early growth response gene-1 (Egr-1) in cultured human retinal pigment epithelial (RPE) cells. Methods Immunofluorescence staining, Western blotting and reverse transcription polymerase chain reaction (RT-PCR) were used to detect and quantitatively analyze the expression of Egr-1 protein and mRNA in cultured human RPE cells which were exposed to stimulants, including 20 mu;g/ml lipopolysaccharide (LPS), 40 ng/ml tumor necrosis factor (TNF)-alpha;, 10 U/ml interferon (IFN)gamma;, 30% supernatant of monocyte/macrophage strain (THP1 cells) and the vitreous humor from healthy human eyeballs, for 0, 10, 20, 30, 40 and 60 minutes, respectively. Results The RPE cells stimulated for 0 minute revealed faint green fluorescence of Egr-1 in the cytoplasm. With exposure to the stimulants, the expressionof Egr-1 increased obviously and b green fluorescence was found in cytoplasm in some nuclei of RPE cells. Compared with the untreated RPE cells, after stimulated by 20 mu;g/ml LPS, 40 ng/ml TNFalpha;, 10 U/ml IFNgamma;, 30% supernatant of THP-1 cells and the vitreous humor, the approximate ultimate amplitudes of Egr-1 mRNA enhanced 1.9, 1.3, 14, 1.2, and 1.4 times, respectively; the greatest amplitudes of Egr-1 protein increased 3.4, 1.2, 1.7, 32, and 1.3 times, respectively. Conclusion LPS, TNF-alpha;, IFN-gamma;, supernatant of THP-1 cells and the vitreous humor can upregulate the expression of Egr-1 mRNA and protein in cultured human RPE cells, and induce its nuclear transposition, which suggests the activation of Egr-1.
Objective To investigate the effects of expression of TNFα mRNA on glucose uptake in both the liver and skeletal muscle after endotoxemia. Methods In the mice with intraperitoneal injection of lipopolysaccharide (LPS), the changes of TNFα level of plasma and uptake of 2-deoxyglucose (2-DG) in the isolated soleus muscle and hepatic tissues were determined, then the reinstatement of glucose uptake by injecting TNF-McAb for 3 days was also observed. In addition, changes of TNFα mRNA expression of liver were evaluated. Results The expression of TNFα mRNA in the liver showed markedly increased in the first 3 hours post endotoxemia and remaind high for 3 days, and the plasma TNFα level paralleled with TNFα mRNA expression of liver also was elevated. The basal uptake of 2-DG both in muscle and liver were markedly increased, but the stimulated 2-DG uptake with insulin was greatly reduced as compared with the control. In addition, these abnormalities of 2-DG uptake can be partially corrected by neutralization of the circulatory TNFα by administration of TNF-McAb. Conclusion The disorders of glucose uptake of the liver and the muscle due to the overexpression of TNFα mRNA and elevated circulatory TNFα level may be the mechanism of insulin resistance after endotoxemia.
PURPOSE:To measure the concentration changes of tumor necrosis factor a (TNF-alpha;)in vitreous during the development of experimental PVR induced by macrophages and explore the initial and mediated factors which stimulate the cellular proliferation. METHODS:Rabbit PVR model was induced by macrophages and the vitreous was taken at the 7th,14th,21st and 28th day and 4 eyes in each group. The TNF-alpha; levels in vivreous of the above examinated and control eyes were measured with an ELISA kit. RESULTS:The TNF-alpha; level in the vitreous reached its peak 434mu;g/ml at 21st day in the mod-el, then rappidly decreased to 122mu;g/ml at 28th day. CONCLUSION:The changes of TNF-a in the vitreous of the PVR model were parallel to the natrual phases of the development of PVR,indicating TNF-alpha; may play an important role in initiating and mediating the inflammation and cellular proliferation in the vitreous. （Chin J Ocul Fundus Dis,1997,13: 231-233）
In order to observe activity of tumor necrosis factor (TNF) in the serum, pancreatic histopathological damage, as well as their relationships in acute necrotizing pancreatitis (ANP), thirty five SD rats were randomly divided into 7 groups according to their sampling time with 5 in each group. ANP was induced by retrograde infusion of 5% sodium taurocholate through biliopancreatic duct in 6 experimental groups (Group B1～B6).Blood and pancreatic tissue samples were obtained at hour 0,0.5,2,4,6 or 8 respectively when the animals were sacrificed.Results showed that serum level of TNF activity rose significantly in Group B2,and reached the maximal value in Group B4.The pancreatic histopathological damage in ANP rats was getting worse along with time. Serum TNF activity had close relation to pancreatic histopathological score (r=0.63, Ｐ＜0.01),suggesting that serum TNF may play an important role in the process of deterioration of pancreatic tissue damage during ANP.
63 normal human gallbladders (non-stone group) and 47 inflammed cholesterol stone gallbladders(stone group) were assayed for the amount of macrophages(ΜΦ),the levels of tumor necro-sis factor (TNF) and interleukin 1(1L-1).It was found that in stone group,the amount of ΜΦ was significantly higher than in non-stone group(ΜΦ4101.90±295.72 vs 572.13±30.07AU,Plt;0.01).The levels of TNF and 1L-1 released mainly from the MΦ in stone group were also significantly increased in comparison with those in non-stone group(TNF 18.12±2.03 vs 4.45±0.39ng/mg,Plt;0.001;1L-1 102.42±7.84 vs 66.75±9.50u/mg protein,Plt;0.05).These results suggest that the activited ΜΦ and increases of TNF,1L-1 may be closely related to the inflammatory reaction in gallbladders and the formation of cholesterol gallstones.