Extra-hepatic infection of hepatitis C virus in the colon tissue and its relationship with hepatitis C virus pathogenesis Hetta, Helal F. and Mekky, Mohamed A. and Khalil, Nasr K. and Mohamed, Wegdan A. and El-Feky, Mohamed A. and Ahmed, Shabaan H. and Daef, Enas A. and Medhat, Ahmed and Nassar, Mahmoud I. and Sherman, Kenneth E. and Shata, Mohamed Tarek M.,, 65, 703-712 (2016), doi = https://doi.org/10.1099/jmm.0.000272, publicationName = Microbiology Society, issn = 0022-2615, abstract= Extra-hepatic compartments might contribute to hepatitis C virus (HCV) persistence and extra-hepatic manifestations. Therefore, we investigated HCV infection in colonic tissue in patients with chronic hepatitis C (CHC) and its relationship with HCV pathogenesis. Colonic biopsies were collected from three groups with CHC infection: treatment naïve (TN; n=12), non-responders (NR; n=10) to anti-HCV therapy (pegylated interferon-α and ribavirin) and sustained virologic response (SVR; n=10) and from a fourth healthy control group (n=10). Liver biopsies were examined to assess inflammation and fibrosis. HCV infection and colonic T regulatory (Treg) frequency were detected by immunohistochemistry. HCV core and NS3 proteins were detected in B cells and macrophage/monocytes of 42 % and 25 % of TN and 50 % and 30 % of NR, respectively, but not in SVR or control group. The numbers of cells expressing HCV proteins were positively correlated with both HCV viral load and colonic Treg frequency. A significant negative correlation between HCV-expressing cells with both liver inflammation and fibrosis was identified. Our study provides evidence that HCV can infect B cells and macrophages of the colon. The correlations between HCV infection in colonic tissue and HCV viral load and liver pathology underline the significance of this extra-hepatic infection in HCV pathogenesis and response to therapy., language=, type=