title: Impact of Pegylated Interferon-alfa-2a on Perforin Level in Patients With Chronic Hepatitis B; Preliminary Study.
abstract: BACKGROUND
  Chronic hepatitis B is one of the most common causes of cirrhosis and hepatocellular toxicity in many countries, including Iran. Cytotoxic T lymphocyte (CTL) and Natural killer (NK) cells are the two of main cell populations considered as cytotoxic cells. One of the distinct pathways CTL and NK cells exert cytotoxicity is perforin/granzyme. After the cytotoxic cell/target cell junction, perforin is released from granules by exocytosis. Once it is anchored, perforin forms cylindrical pores through which granzymes and granulysin enter and induce apoptosis.
  
  
  OBJECTIVE
  Large controlled trials have demonstrated the efficacy of PEG-IFN-α-2a in treatment of chronic hepatitis B. This study was aimed to examine whether the enhancement of cytotoxicity by PEG-IFN-α-2a is mainly due to the perforin pathway.
  
  
  METHODS
  This research work was performed on 50 patients and five healthy people. Patients with chronic hepatitis B were further subdivided into two groups: patients with inactive chronic hepatitis B (carriers, n = 30), and those with active chronic hepatitis B who were under treatment with PEG-IFN-alfa-2a (n = 20) for minimum six and maximum 12 months. Serum perforin level was measured using ELISA method (CUSABIO Company), HBV viral load was assessed using COBAS Taq-man, and we used Elecsys hepatitis B surface antigen (HBs Ag) II quantitative assay method for HBs Ag determination. HBeAg was evaluated by ELISA method, and AST and ALT were measured by routine laboratorymethods.
  
  
  RESULTS
  Based on the results obtained serum perforin level in healthy group was 0.64 ng/mL, the mean of serum perforin level in inactive HBs Ag carriers was 2.63ng/mL, and 4.63 ng/mL in patients with active chronic hepatitis B under treatment with PEG-IFN-α-2a. The mean of serum perforin level in patients with and without virologic response to treatment were 5.45 ng/mL,and 3.4 ng/mL respectively. Finally in patients with virologic response and seroconverted serum perforin level was 7.23 ng/mL.
  
  
  CONCLUSIONS
  Based on our results higher perforin level in patients under treatment with PEG-IFN-α-2a, could be an indication of elevated cytotoxicity via perforin/granzyme pathway.
authors.affiliation: Department of Laboratory Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Meisam
authors.initials: M
authors.lastname: Mahdavi
authors.affiliation: Department of Laboratory Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Houshang
authors.initials: H
authors.lastname: Amirrasouli
authors.affiliation: Baqiyatallah Research Center for Gastroenterology and Liver Diseases, Baqiyatallah University of Medical Sciences, Tehran, IR Iran ; Middle East Liver Diseases Center (MELD Center), Tehran, IR Iran.
authors.forename: Seyed Moayed
authors.initials: SM
authors.lastname: Alavian
authors.affiliation: Middle East Liver Diseases Center (MELD Center), Tehran, IR Iran.
authors.forename: Bita
authors.initials: B
authors.lastname: Behnava
authors.affiliation: Department of Laboratory Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Faranak
authors.initials: F
authors.lastname: Kazerouni
authors.affiliation: Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, IR Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Keshvari
authors.affiliation: Department of Laboratory Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Namaki
authors.affiliation: Biostatistic Department, Faculty of Medicine, Tarbiat Modares University, Tehran, IR Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Gholami Fesharaki
authors.affiliation: Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Hooman
authors.initials: H
authors.lastname: Rahimipour
authors.affiliation: Department of Laboratory Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Jahangir
authors.initials: J
authors.lastname: Mohammadzade
authors.affiliation: Department of Microbiology, Faculty of Basic Sciences, Islamic Azad University, North Tehran Branch, Tehran, IR Iran.
authors.forename: Farahnaz
authors.initials: F
authors.lastname: Zohrehbandian
authors.affiliation: Faculty of Medicine, Ilam University of Medical Sciences, Ilam, IR Iran.
authors.forename: Fazel
authors.initials: F
authors.lastname: Mahdavipour
keywords: Hepatitis B; PEG-IFN-Alfa-2a; Perforin