Epidemiological profile of hepatitis B virus infection in Iran in the past 25 years; a systematic review and meta-analysis of general population studies

Background: Chronic hepatitis B virus [HBV] infection is one of the most important health problems worldwide with a high rate of morbidity and mortality. It is a major risk factor for cirrhosis and liver cancer. Currently, Iran is located in the intermediate HBV zone; however, recent studies have provided some evidence indicating an epidemiological change in the country. The aim of this study was to estimate the prevalence of HBV in Iran

Methods: A systematic review was conducted to evaluate the studies performed in the past 25 years that have reported the prevalence of HBV infection and its associated factors in the Iranian general population [1990-2014]. Any study assessing and reporting serum Hbs Ag levels was included in this review

Results: After excluding all impertinent studies, 19 eligible studies were included in the analysis. The overall prevalence of HBV was 3% [95% CI 2% to 3%]. Its distribution showed that the prevalence of HBV varies in different provinces from 0.87% to 8.86%. The HBV rate was highest in the Golestan [8.86%] and lowest in the Kurdistan [0.87%] provinces

Conclusion: This study provides some evidence about the prevalence of HBV in Iran. However, the collected data was very heterogenic, even within a single province, which made it hard to estimate a single-point prevalence. High quality studies are needed to find reliable information about HBV prevalence and to decrease the heterogeneity of results in the country

[TGF-bReceptor2 knocked down by SiRNA increases cord blood CD34+ HSCs self-renewal]

Nowadays, cord blood Hematopoietic stem cells [HSCs] are known as a valuable source for bone marrow transplantation but unfortunately their insufficient number is a limiting factor for using them in adult bone marrow transplantation. Cord blood HCSs expansion is an approach to overcome this problem, by inducing their self-renewal. TGF-b signaling pathway is a key inhibitory agent for HSCs self-renewal. In this study, we tried to enhance self-renewal of long term culture initiating cell by inhibiting TGFbR2 expression. CD34+ HSCs were isolated from cord blood units with MACS column. SiRNA against TGFbR2 was transfected by Lipofectamine [TM] RNAiMAX as transfection reagent. HSCs were cultured in IMDM medium containing 10% FBS and early acting cytokines [Flt3L, SCF, Tpo] for 8 days. Then we evaluated TGFbR2 expression by QRT-PCR. The CD34+ subpopulation of cultured cells were examined by flow cytometry on the 8th day. Finally the expanded cells were evaluated for the presence of early hematopoietic stem cells by LT-CIC and clonogenic assays. According to our results, TGFbR2 down regulation increases CD34+ subpopulation of HSCs. In addition, LT-CIC assay showed an enhancement in primitive hematopoietic stem cell capable of self-renewal. All in all, it seems that positive regulators have attracted more attention in the field of HSCs expansion while negative regulators have same importance in self-renewal process of HSCs and their inhibition can be a beneficial tool for enhancement of HSCs self-renewa