Dose effect of LPS on Cytokine mRNA Expressions by Mouse Peritoneal Macrophages

Many studies for LPS-induced cytokines, chemokines gene expressions have been reported, but results are highly diverse. The dose of LPS used, cell type studied or other technical factors may contribute to the differences. We investigated the cytokine mRNA expressions, interleukin-2 (IL-2), IL-6, IL-10 and IFNr, on thioglycollate (TG) elicited-mouse peritoneal macrophages stimulated with various concentrations, 1 ng/ml, 10 ng/ml, 100 ng/ml, 1 ug/ml and 10 ug/ml, of LPS used by reverse transcription polymerase chain reaction (RT-PCR) and northern blot analysis. TG- elicited peritoneal macrophages expressed IL-6 and IFN-r mRNA in a dose-dependent manner. The expressions of IL-2 and IL-10 mRNA were dose-independent manner. In northern blot analysis, IL-6 mRNA expression was detected only in 10 ug/ml LPS concentration for short stimulation time (0.5 h), while IL-10 mRNAs were expressed evenly in all LPS concentrations. The expression of IL-6 mRNA was sustained until 72 h at 10 ug/ml concentration only, but IL- 10 mRNAs of all cases of LPS concentrations were sustained evenly until then. These results suggest that the concentration of LPS required for cytokine induction must be determined differently from gene to gene types, and although LPS concentration 10 ug/ml has not been used as an ordinary concentration in vitro cytokine study, 10 ug/ml of LPS might be more appropriate concentration in the study of IL-6 expression on mouse peritoneal macrophages.

Detection of Helicobacter DNA in the Bile from the Obstructed Bile Duct / 대한내과학회지

OBJECTIVE: Several newly recognized Helicobacter spp. such as H. hepaticus, H. bilis, H. cholecystus, H. rappini, H. pullorum, can cause persistent hepatitis, hepatoma, cholangiopancreatitis, and cholecystitis in animals. Recently some studies have been reported that Helicobacter DNA can be found in the bile from the patients with diseased bile duct, although its clinical significance is still unclear. The aim of this study is to investigate the existence, and character of Helicobacter in the bile from the obstructed bile duct, and the relationship with pH and the other bacteria found in the bile. METHODS: Twenty-eight bile samples (15 from bile duct cancer, 6 from pancreatic head cancer, 7 from bile duct stones) were obtained from the PTBD route. Bile pH measurement, and Helicobacter culture in microaerophil uric and anaerobic conditions were performed. The primers chosen for polymerase chain reaction (PCR) amplification for detection and characterization were ureA (411 bp) and cagA gene (298 bp), respectively. And primer of 16s rRNA for all known bacteria including Helicobacter was used, and the kinds of bacteria were identified by RFLP. RESULTS: Helicobacter DNA was detected in 39.3%. The bile pH was not related with presence of Helicobacter (7.83 +/-0.41 vs 7.78+/-0.48). The prevalence of cagA was 35.7%, and 16s rRNA was found in 46.4%. The specific 16s rRNA band for Helicobacter was observed in 14.3%. All the culture were not successful. CONCLUSION: Although the Helicobacter spp. were not cultured, Helicobacter exists obviously in the bile from the diseased bile duct, and coexist with other bacteria. These results should stimulate studies to ascertain whether these Helicobacter play a role in the pathogenesis of bile duct diseases in human.