Expression of HCV genotype-4 core antigen in prokaryotic E. coli system for diagnosis of HCV infection in Egypt.

BACKGROUND: Egypt has a high prevalence of hepatitis C virus (HCV) infection with 92.5% of genotype-4. AIM: This study aimed to clone and express the core gene of HCV genotype-4 for using it to develop a highly sensitive, specific, and cost-effective diagnostic assay for detecting HCV infection. METHODS: Using synthetic HCV genotype-4 core gene, pET15b as E. coli expression vector, and 1 mM lactose as inducer, the HCV core protein (MW 17 kDa) was expressed in the form of inclusion bodies (IBs) that was purified and solubilized using 8 M guanidinium HCl. The recombinant core protein was in vitro refolded by a rapid dilution method for further purification using weak cation exchange liquid chromatography. The immunogenicity of the purified protein was tested by ELISA using 129 serum samples. RESULTS: The recombinant core protein was successfully expressed and purified. The results also showed that the in-house anti-HCV core assay is accurate, specific (~96.6%), and highly sensitive (~100%) in accordance with the commercial ELISA kit. CONCLUSION: The sensitivity, specificity, and reproducibility of the developed assay were high and promising to be used as a screening assay for detecting HCV infection.

Gut microbiota modulation as a promising therapy with metformin in rats with non-alcoholic steatohepatitis: Role of LPS/TLR4 and autophagy pathways.

Gut microbiota is a crucial factor in pathogenesis of non-alcoholic steatohepatitis (NASH). Therefore, targeting the gut-liver axis might be a novel therapeutic approach to treat NASH. This study aimed to investigate the therapeutic effects of a probiotic (Lactobacillus reuteri) and metronidazole (MTZ) (an antibiotic against Bacteroidetes) either alone or in combination with metformin (MTF) in experimentally-induced NASH. NASH was induced by feeding rats high fat diet (HFD) for 12 weeks. MTF (150 mg/kg/day) or L. reuteri (2x109 colony forming unit/day) were given orally for 8 weeks; meanwhile, MTZ (15 mg/kg/day, p.o.) was administered for 1 week. Treatment with L. reuteri and MTZ in combination with MTF showed additional benefit compared to MTF alone concerning lipid profile, liver function, oxidative stress, inflammatory and autophagic markers. Furthermore, combined regimen succeeded to modulate acetate: propionate: butyrate ratios as well as Firmicutes and Bacteroidetes fecal contents with improvement of insulin resistance (IR). Yet, the administration of MTF alone failed to normalize Bacteriodetes and acetate contents which could be the reason for its moderate effect. In conclusion, gut microbiota modulation may be an attractive therapeutic avenue against NASH. More attention should be paid to deciphering the crosstalk mechanisms linking gut microbiota to non-alcoholic fatty liver disease (NAFLD) to identify new therapeutic targets for this disease.