Résumé
Objective To explore the antiviral effect and mechanism of interferon-α (IFN-α) in chronic HBV infection mouse model by hydrodynamic tail vein injection. Methods Chronic HBV infection mouse model was constructed with C57BL/6j mice by hydrodynamic tail vein injection of pAAV-HBV1.2 plasmid. Serum IFN-α was determined by ELISA after injection of IFNα- expressing plasmid (i.e., plasmid pKCMvint.IFN-α-2a) or control plasmid pKCMvint. HBsAg and HBeAg levels were assayed on Abbot ARCHITECT i2000SR. Total lymphocytes in liver or spleen were counted and the frequency and function of CD8+T cells and HBV-specific CD8+T cells were analyzed by flow cytometry. Results Serum IFN-α expression level was significantly higher in the animals injected with pKCMvint.IFN-α-2a plasmid than in control group (P＜0.01). Serum HBsAg decreased quickly 12 days after injection and significantly lower than control group. Serum HBeAg was undetectable after IFN-α expression. Interestingly, the frequency of CD8+T cells in the liver of animals injected with pKCMvint.IFN-α-2a plasmid was significant higher than control group (P＜0.05), while total liver lymphocytes and HBV-specific CD8+T cells had a similar trend. Consistently, the HBV-specific CD8+T cells in IFN-α-expressing animals showed higher level of producing IFN-γ, TNF-α and IL-2 than control group. IFN-γ production was significantly different between IFN-α- expressing group and control group (P＜0.05). Conclusions IFN-α can increase the frequency and function of liver CD8+T cells to inhibit HBV gene expression in chronic HBV infection mouse model.
Résumé
Background:Acute gastroenteritis is the second largest public health problem in the world. Rotavirus(RV)is one of the pathogens of acute gastroenteritis in adults,researches focusing on RV infection may provide the basis for prevention and control of the disease. Aims:To determine the epidemiological characteristics of RV infection in adults with acute gastroenteritis in Shanghai,China. Methods:From Jun. 2010 to Dec. 2013,stool samples and clinical data in adults with acute gastroenteritis in a designated hospital in Shanghai Changning District were collected. ELISA and PCR were used to detect RV infection and its genotypes. Results:A total of 1 554 eligible stool samples from acute gastroenteritis patients were recruited,of them 691 were males and 863 were females,the mean age was(46. 19 ± 15. 59)years old. RV was detected in 189 patients with a detection rate of 12. 2% ,163(10. 5% )were categorized as group A RV and 26(1. 7% ) were group B/ C RV;the most common genotypes in group A RV were G9(30. 1% )and G1(25. 2% ). Watery stool and vomiting were more prevalent in RV-positive patients than in RV-negative patients(P < 0. 05). The detection rates in years 2010,2011,2012 and 2013 were 12. 2% ,14. 9% ,6. 8% and 16. 3% ,respectively. When analyzed by age group,the detection rate was significantly lower in 18-39 years group than those in 40-59,60-79,and ≥80 years groups(8. 7% vs. 14. 8% ,14. 2% ,and 17. 1% ,P < 0. 05). The peak of epidemic was from Nov. to next Feb. Conclusions:RV infection in adults with acute gastroenteritis is more popular in middle aged and elderly people and shows a winter seasonality in Shanghai,China. The most common genotypes of group A RV are G9 and G1.