Expression of CD4+CD25+ regulatory T cells and Foxp3 in peripheral blood of patients with gastric carcinoma

The aim of this research was to study the clinical significance and expression of CD4+CD25+ regulatory T cells (Tregs) and p3Forkhead transcription factor-3 (Foxp3) in peripheral blood of patients with gastric carcinoma (GC) and to investigate the effects in the occurrence and development process of GC, to further comprehend their clinical values and provide a theoretical basis for the early diagnosis and immunotherapy of GC. The expression levels of CD4+CD25+Foxp3+Tregs in GC patients, at TNM staging, differentiated degree, lymphatic metastasis, cancer sites and cancer diameter of GC, were analyzed within the groups. The comparison of the expression levels of CD4+CD25+Foxp3+Tregs in peripheral blood between the GC group and the healthy control group showed a statistically significant difference. At TNM staging within the groups, pairwise comparisons of the expression levels of CD4+CD25+Foxp3+Tregs indicated that differences among the stage I+II group, stage III group and stage IV group were statistically significant. The expression levels of CD4+CD25+Foxp3+Tregs are closely relative to the occurrence and development of GC, providing theoretical bases and evidence for the early diagnosis, prognosis evaluation and immunotherapy of GC.

Lipopolysaccharide results in a marked decrease in hepatocyte nuclear factor 4 alpha in rat liver

The acute-phase response can result in decreased liver-specific functions and death as a result of liver failure. We show here that lipopolysaccharide (LPS), an endotoxin that induces the acute-phase response, results in a marked decrease in the major isoforms of the transcription factor, hepatocyte nuclear factor 4 alpha (HNF-4 alpha), in livers of rats. HNF-4 alpha is a nuclear receptor that is critical for the expression of several liver-specific genes. This decrease in HNF-4 alpha is primarily the result of a posttranscriptional mechanism, because mRNA levels are normal, and there are no major changes in the splicing patterns. This decrease was of functional significance, because expression of a gene that is highly dependent on HNF-4 alpha, HNF-1 alpha, was reduced. Interleukin-1 beta (IL-1 beta) is a cytokine whose levels are increased in vivo in response to LPS. IL-1 beta resulted in a decrease in HNF-4 alpha levels in HepG2 cells. This IL-1 beta-induced decrease was likely caused by degradation via the proteasome, because it was prevented by the addition of the proteasome inhibitor, MG132. We conclude that the decrease in HNF-4 alpha that occurs in vivo after the administration of LPS may be the result of IL-1 beta-induced degradation, and likely contributes to the liver insufficiency that occurs. IL-1 beta antagonists or proteasome inhibitors might increase HNF-4 alpha protein levels in the acute-phase response, which could result in increased liver function and survival.

Quantitative variation in vascular endothelial growth factor mRNA expression during early flexor tendon healing: an investigation in a canine model

Vascular endothelial growth factor (VEGF) is a potent mediator of angiogenesis, with direct mitogenic activity on cells of endothelial origin. We quantified the temporal accumulation of VEGF mRNA at the repair site of an in vivo canine intrasynovial flexor tendon repair and rehabilitation model by means of quantitative Northern blot analysis, in order to detail a molecular signal involved in the intrinsic angiogenic process that accompanies early flexor tendon healing. Significant accumulation of VEGF mRNA occurred at the flexor tendon repair site at 7 days post-operatively, with peak levels seen at post-operative days 7 and 10. Levels returned to baseline by day 14. Local VEGF mRNA accumulation at the repair site temporally precedes and is spatially distinct from the vascular ingrowth itself, which has been shown to occur maximally at day 17. These data suggest that cells within the flexor tendon repair site are involved in molecular processes other than the synthesis of extracellular matrix, such as modulation of angiogenesis.

Lovastatin decreases mortality and improves liver functions in fulminant hepatic failure from 90% partial hepatectomy in rats

BACKGROUND/AIMS

Liver insufficiency occurs when the liver cannot perform critical functions such as ammonia metabolism, gluconeogenesis, or production of coagulation factors The hypothesis of this study was that decreased function of existing hepatocytes may contribute to hepatic failure, and that the function of these cells might be increased pharmacologically. Lovastatin is a 3-hydroxy-3-methylglutaryl CoA reductase inhibitor that inhibits cholesterol biosynthesis and affects the activity of some signal transduction pathways and liver transcription factors. Changes in hepatic transcription factors during liver regeneration might result in decreased liver functions, and lovastatin might prevent these changes

METHODS

Rats received 90% partial hepatectomy (90% PH), and either lovastatin or vehicle alone daily. Survival and liver functions were assessed.

RESULTS

Lovastatin increased survival to 58% (vs. 6% in controls that received 90% PH without drug), decreased the peak ammonia level to 427 microM (vs. 846 microM in controls), increased the nadir of glucose to 88 mg/dl (vs. 57 mg/dl in controls), decreased the peak prothrombin time to 23 s (vs 29 s in controls), and decreased the peak activated partial thromboplastin time to 29 s (vs. 39 s in controls). The full survival and metabolic benefits were observed when lovastatin was started at 30 min after 90% PH, but lovastatin was less efficacious when started at later times.

CONCLUSIONS

Lovastatin increases the function of existing hepatocytes and might be used to improve liver function after extensive hepatic resection.

Lipopolysaccharide potentiates the effect of hepatocyte growth factor on hepatocyte replication in rats by augmenting AP-1 activity

The liver regenerates by replication of differentiated hepatocytes after damage or removal of part of the liver. Although several growth factors and signaling pathways are activated during regeneration, it is unclear as to which of these are essential for hepatocyte replication. We show here that low- (1 mg/kg) and high- (10 mg/kg) dose hepatocyte growth factor (HGF) induced replication of 2.1% and 11.1% of hepatocytes in rats, respectively. Lipopolysaccharide (LPS), an inducer of the acute phase response, augmented hepatocyte replication in response to low- and high-dose HGF by 4- and 2-fold, respectively. HGF alone induced moderate levels of c-Jun-N-terminal kinase (JNK) and p44/p42 mitogen-activated protein kinase (MAPK), resulting in moderate levels of AP-1-DNA binding activity. The combination of LPS + HGF increased JNK and AP-1-DNA binding activity more than levels seen with LPS or HGF alone. The activation of Stat3 that was observed after administration of LPS + HGF, but not HGF alone, could contribute to increased transcription of AP-1 components. Because phosphorylation of the c-Jun component of AP-1 by JNK increases its ability to activate transcription, the AP-1 in hepatocytes from animals treated with LPS + HGF may be more active than in rats treated with LPS or HGF alone. LPS may contribute to hepatocyte replication by potentiating the effect of HGF on the activation of both AP-1-DNA binding and transcriptional activity.

Substance P- and 5-hydroxytryptamine-mediated depolarization in sympathetic ganglion neurons

By means of intracellular recordings from sympathetic ganglion in vitro, the present study was to investigate whether the receptors of substance P (SP) and 5-hydroxytryptamine (5-HT) exist in the same neuron or separately in different neurons of guinea pig celiac ganglion (CG) and inferior mesenteric ganglion (IMG) and whether there are some interactions between the two transmitters. Of the 133 neurons of CG, 66 (49.6%) responded to both SP and 5-HT, 40 (30.1%) only to SP or 5-HT, 27 (20.3%) insensitive to both. The corresponding numbers of the corresponding groups of neurons of the 129 IMG neurons are 47 (36.4%), 65 (50.4%) and 17 (13.2%). Continuous superfusion of IMG with 5-HT did not affect SP depolarization, while continuous superfusion of IMG with SP did not affect 5-HT depolarization. The results indicate that SP receptor and 5-HT receptor may exist in the same neuron, and neither affects each other.

5-HT1P receptor-mediated slow depolarization in neurons of guinea pig inferior mesenteric ganglion

AIM

To study the effects of several 5-hydroxytryptamine (5-HT) receptor subtype antagonists on 5-HT-induced depolarization and the effects of 5-HT1P receptor agonist on the membrane potential in the neurons of guinea pig inferior mesenteric ganglion (IMG).

METHODS

Intracellular recordings were made from neurons of the isolated guinea pig IMG.

RESULTS

Cyproheptadine (5-HT1/2 antagonist 10 mumol.L-1, n = 7) and BRL 24924 (5-HT1P antagonist 10 mumol.L-1, n = 19) reversibly suppressed 5-HT slow response; pressure ejection of MCPP (5-HT1P agonist 10 mmol.L-1) induced a slow depolarization in most of 5-HT sensitive neurons (10/14).

CONCLUSION

5-HT-induced slow depolarization is mediated by 5-HT1P receptor.

Intramuscular injection of an adenoviral vector expressing hepatocyte growth factor facilitates hepatic transduction with a retroviral vector in mice

Retroviral vectors can result in therapeutic and stable levels of expression of proteins from the liver. However, most retroviral vectors transduce only dividing cells, and hepatocytes are normally quiescent. The goal of this study was to determine if an adenoviral vector could transiently express hepatocyte growth factor (HGF) in order to induce hepatocyte replication and facilitate retroviral vector transduction of the liver. Intramuscular injection of an adenoviral vector that expressed human HGF from the cytomegalovirus promoter (Ad.CMV.HGF) resulted in moderate levels of HGF in blood and liver, and replication of 3 to 12% of hepatocytes. No cytopathic effect was observed in the liver, and a control adenoviral vector induced no or lower levels of replication. When a retroviral vector expressing beta-galactosidase cDNA was injected into a peripheral vein during the peak period of hepatocyte replication induced by intramuscularly administered Ad.CMV.HGF, 8% of hepatocytes were transduced. We conclude that intramuscular injection of Ad.CMV.HGF is a safe and effective way to induce transient systemic expression of HGF and hepatocyte replication, and to facilitate transduction of hepatocytes with a retroviral vector.

Embolization of portal vein branches induces hepatocyte replication in swine: a potential step in hepatic gene therapy

PURPOSE

To determine whether embolization of portal vein branches would stimulate hepatocyte replication in pigs.

MATERIALS AND METHODS

The portal vein branches supplying 50%-70% of the liver were embolized in eight pigs by using a combination of coils and polyvinyl alcohol particles. The extent of embolization was assessed at portography in all animals and at computed tomography in one animal. Hepatocyte replication was determined by calculating the percentage of cells that incorporated bromodeoxyuridine into their nuclei. Animals survived up to 35 days after the procedure.

RESULTS

Embolization of the portal vein branches supplying the left and median lobes caused transient increases of less than 70% in portal vein pressures and of less than 100% in liver enzyme levels. Indocyanine green clearance was measured in two animals and decreased less than 50%. The percentage of replicating hepatocytes in the nonembolized lobe was 0% on day 0, 7% on day 2, 14% on day 7, and 2% on day 12.

CONCLUSION

Substantial hepatocyte replication occurred 2-7 days after embolization of portal vein branches. Further research will help determine if this procedure can facilitate retroviral transduction in large animals. If successful, the low morbidity of this method may allow its use in humans for gene therapy.

Therapeutic levels of human protein C in rats after retroviral vector-mediated hepatic gene therapy

Protein C deficiency results in a thrombotic disorder that might be treated by expressing a normal human protein C (hPC) gene in patients. An amphotropic retroviral vector with a liver-specific promoter and the hPC cDNA was delivered to rat hepatocytes in vivo during liver regeneration. Expression of hPC varied from 55 to 203 ng/ml (1.3-5.0% of normal) for 2 wk after transduction. Expression increased to an average of 900 ng/ml (22% of normal) in some rats and was maintained at stable levels for 1 yr. All of these rats developed anti-hPC antibodies and exhibited a prolonged hPC half-life in vivo. The hPC was functional as determined by a chromogenic substrate assay after immunoprecipitation. We conclude that most rats achieved hPC levels that would prevent purpura fulminans, and that hepatic gene therapy might become a viable treatment for patients with severe homozygous hPC deficiency. Anti-hPC antibodies increased the hPC half-life and plasma levels in some rats, but did not interfere with its functional activity. Thus, the development of antibodies against a plasma protein does not necessarily abrogate its biological effect in gene therapy experiments.

[Receptors of monoamine in sympathetic preganglionic neurons of neonatal rat spinal cord in vitro]

By means of intracellular recordings from spinal cord slices of neonatal rats in vitro, the effects of 5-hydroxytryptamine (5-HT), nor-adrenaline (NA) and adrenaline (AD) on membrane potential in sympathetic preganglionic neurons (SPN) were observed, in order to clarify whether these neuron contain a single type of the monoamine receptor or in combination with more than one type of receptors. The results showed that: (1) 5-HT, NA and AD induced membrane depolarization respectively in 57.1% (16/28), 60% (15/25) and 52.4% (11/21) of SPN. (2) According to the reactions of SPN to the three monoamines, several subtypes of SPN could be divided: those sensitive to all the three monoamines (3/19), those sensitive to two of them (9/19), those only sensitive to one type of monoamines (4/19) and those insensitive at all (3/19). The significance of coexistence of more than one type of the three monoamines in a single neuron remains to be elucidated.

Therapeutic levels of functional human factor X in rats after retroviral-mediated hepatic gene therapy

Factor X deficiency results in a rare but serious bleeding disorder that might be treated by expressing a normal factor X gene in patients. We generated an amphotropic retroviral vector with the human FX cDNA and delivered it to rat hepatocytes in vivo during liver regeneration. The human alpha1-antitrypsin promoter was chosen to direct expression because it was the most efficient of several tested in yielding expression of alpha1-antitrypsin protein from a retroviral vector in hepatocytes in vivo. We achieved expression of factor X in four rats at levels sufficient to maintain hemostasis in humans (10% to 43% of normal). The factor X was determined to be functional by using a chromogenic substrate assay after immunoprecipitation with human specific antibodies. Expression of factor X remained stable for more than 10 months in two rats. It is likely that expression will be maintained for the life of the animals, because retroviral vectors integrate into the chromosome and hepatocytes are long-lived. The high and stable levels of expression achieved using this liver-specific promoter overcomes one of the two major obstacles to successful human gene therapy for hemophilia.

Portal branch occlusion safely facilitates in vivo retroviral vector transduction of rat liver

Hepatic gene therapy might correct the clinical manifestations of several genetic disorders in patients. Although retroviral vectors with a strong liver-specific promoter can result in stable and therapeutic levels of expression of genes from the liver, application of these techniques in humans is limited by the need to perform one or more invasive procedures to achieve ex vivo or in vivo transduction of hepatocytes. In vivo delivery involves injection of retrovirus into the portal vein during liver regeneration. Although transduction is efficient and specific for the liver, induction of hepatocyte replication requires a 70% partial hepatectomy or administration of a liver toxin. An alternative method for inducing hepatocyte replication is to occlude branches of the portal vein. This results in apoptosis of hepatocytes in the occluded lobes and compensatory replication of the hepatocytes in the nonoccluded lobes. We demonstrate here that portal branch occlusion is nearly as effective as partial hepatectomy at facilitating retroviral vector transduction in vivo and has a lower morbidity. Portal branch occlusion could be performed in larger animals by minimally invasive techniques and has been used safely to treat human patients with liver cancer. Portal branch occlusion might ultimately be used in humans to facilitate retroviral vector transduction in vivo for the treatment of genetic diseases.

[The relationship of late slow excitatory potential with 5-hydroxytryptamine and substance P in the guinea-pig celiac ganglion]

The work was carried out to investigate the relationship of non-cholinergic late slow excitatory potential (LS-EPSP) with 5-hydroxytryptamine (5-HT) and substance P (SP) in the neurons of the guinea pig celiac ganglion (CG) using intracellular electrodes in vitro. During repetitive stimulation of the splanchnic nerve (SN), LS-EPSP following a series of action potentials could be recorded in 161 out of 206 neurons (78.2%); Application of 5-HT and SP by superfusion or pressure ejection induced 5-HT depolarization in 102 out of 149 neurons (68.5%) and SP depolarization in 98 out of 188 neurons (52.1%), respectively; Most neurons, from which LS-EPSP could be recorded during stimulation of SN, were sensitive to 5-HT (73/88, 83.0%) and SP (68/114, 59.7%). However, only a small number of neurons not showing LS-EPSP during stimulation of SN were sensitive to 5-HT (10/26, 38.5%, P < 0.0001) and SP (11/36, 30.6%, P < 0.01). The results support the viewpoint that both 5-HT and SP are involved in the formation of LS-EPSP as transmitters; In addition, both effects of 5-HT and SP were examined in 133 neurons. There were 66 of these neurons (49.6%) to be sensitive to both 5-HT and SP, suggesting that there may be some functional relations between 5-HT and SP in the neurons of guinea pig CG.

New sequential external counterpulsation for the treatment of acute myocardial infarction

Over a period of 6 years, 52 patients with acute myocardial infarction (AMI) were treated with sequenced external counterpulsation (SECP). Of the 23 patients who experienced severe chest pain, 22 had complete relief within 30 min of SECP, and 31 of the 52 patients showed remarkable improvement in their electrocardiogram after the first hour of treatment. Fifteen patients were studied using the 35-lead ST segment elevation-mapping method. sigma ST and NST, indicators of infarct size, showed decreasing trends in seven patients treated with SECP for a period of 6 days, whereas sigma ST and NST of the control group of eight patients increased during the same period. Our hemodynamic data indicate that in four of five patients with AMI and left heart failure, the central venous pressure and cardiac output increased after SECP, whereas the pulmonary wedge pressure decreased. Measurements of the P-wave terminal force of lead V1 also demonstrated that the application of SECP can improve left ventricular function in a majority of patients with AMI.