en عمومى General پژوهشي Original article <div><strong>Background and Aims:</strong> The use of herbal remedies, either in combination with conventional drugs or as an alternative, is accepted worldwide. Silymarin derived from Milk thistle has evidence-based therapeutic potency for wide spectrum of liver diseases. The current work aimed to study the immune-modulating activity of Silymarin in HCV-infected patients by measuring the effect of pure Silymarin solution on the production of IL-17 and IL-10.<br> <strong>Materials and Methods:</strong> Nine HCV-1a infected patients and three healthy controls were entered in this study. The mean age of patients and healthy controls were 45.53 (&plusmn; 10.21) and 39.9 (&plusmn;10.88), respectively. The PBMCs were isolated, cultured in 96-well plate and incubated with Silymarin solution (5&micro;g/ml) for 24 hours. The cells and cell culture supernatant of three groups including patients treated with Silymarin, non-treated patients, and healthy controls were then subjected to Real Time PCR and ELISA to measure the levels of inflammatory and non-inflammatory cytokines including IL-17 and IL-10, respectively. Statistical analysis was conducted using SPSS software version 20.0.<br> <strong>Results:</strong> According to Real Time PCR and ELISA results, the level of IL-17 was significantly reduced in patients treated with Silymarin while the expression of IL-10 was remarkably increased in these patients.<br> <strong>Conclusion: </strong>The results of this study approved the immunomodulatory properties of Silymarin in HCV-infected patients. Hepatoprotective, antiviral, as well as immune-modulatory properties of the Silymarin make it a potential therapeutic option in patients with chronic hepatitis C.</div> Silymarin, Hepatitis C Virus (HCV), Interleukin 10 (IL-10), Interleukin 17 (IL-17), Real Time PCR, ELISA 45 49 http://journal.isv.org.ir/browse.php?a_code=A-10-263-1&slc_lang=en&sid=1 Pedram Attar Delgosha pedy.delgosha@gmail.com 10031947532846007249 10031947532846007249 No Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Mehrdad Ravanshad ravanshad@modares.ac.ir 10031947532846007250 10031947532846007250 Yes Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Ali Maleki Ali Maleki 10031947532846007251 10031947532846007251 No Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran