title: Characterization of a Chikungunya virus strain isolated from banked patients' sera.
abstract: Chikungunya virus (CHIKV) is a prevalent mosquito-borne pathogen that is emerging in many parts of the globe causing significant human morbidity. Here, we report the isolation and characterization of an infectious CHIKV from banked serum specimens of suspected patients from the 2009 epidemic in Thailand.
  
  
  
  Standard plaque assay was used for CHIKV isolation from the banked serum specimens. Isolated CHIKV was identified base on E1 structural gene sequence. Growth kinetic, infectivity, cell viability and cytokine gene expression throughout CHIKV infection in a permissive cell line, 293T cells, was performed using several approaches, including standard plaque assay, immunofluorescence assay, classical MTT assay, and quantitative real-time PCR. Two tailed Student's t test was used for evaluation statistically significance between the mean values of the groups.
  
  
  
  Based on the E1 structural gene sequence and phylogenetic analysis, we identified the virus as the CHIK/SBY8/10 isolate from Indonesia. Assessment of the growth kinetics, cytopathic effects as well as its ability to induce cellular immune responses suggested that the currently isolated CHIK/SBY8/10 virus is relatively more virulent than a known CHIKV vaccine strain, which also induces more dramatic proinflammatory responses.
  
  
  
  Our studies further add to the infectivity of a less-studied yet infectious CHIKV isolate as well as underscored the importance and utility of 293T cells as an excellent cell culture model for studying viral growth, CHIKV-induced inflammatory cellular responses and cell death. Together, these studies provide novel information on the CHIKV biology, infectivity and virus-cell interaction, which would help develop novel interventions against the infection.
authors: Department of Molecular Biotechnology and Bioinformatics, Faculty of Science, Prince of Songkla University, Hatyai, Songkhla, 90112, Thailand.
authors: Pattra
authors: P
authors: Chalaem
authors: Division of Infectious Disease, Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Hatyai, Songkhla, 90112, Thailand.
authors: Sarunyou
authors: S
authors: Chusri
authors: Department of Virology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, Thailand.
authors: Stefan
authors: S
authors: Fernandez
authors: Department of Molecular Biotechnology and Bioinformatics, Faculty of Science, Prince of Songkla University, Hatyai, Songkhla, 90112, Thailand.
authors: Wilaiwan
authors: W
authors: Chotigeat
authors: CIC bioGUNE, 48160, Derio, Bizkaia, Spain.|Ikerbasque, Basque Foundation for Science, 48011, Bilbao, Bizkaia, Spain.
authors: Juan
authors: J
authors: Anguita
authors: Department of Veterinary Medicine and Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD, 20742, USA.
authors: Utpal
authors: U
authors: Pal
authors: Department of Molecular Biotechnology and Bioinformatics, Faculty of Science, Prince of Songkla University, Hatyai, Songkhla, 90112, Thailand. kpromnares@gmail.com.
authors: Kamoltip
authors: K
authors: Promnares
mesh_terms: D002460:Cell Line; D065632:Chikungunya Fever / Q000453:epidemiology / Q000821:virology*; D002646:Chikungunya virus / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D058872:Epidemics; D006801:Humans; D010949:Plasma / Q000821:virology*; D017422:Sequence Analysis, DNA; D013785:Thailand / Q000453:epidemiology; D010948:Viral Plaque Assay; D015678:Viral Structural Proteins / Q000235:genetics; D014779:Virus Replication
chemical_list: D015678:Viral Structural Proteins
keywords: 293T cells; CHIK/SBY8/10 isolate; CHIKV 181/clone 25; Chikungunya virus; Cytokines; Gene expression