リバースジェネティクス法を用いた新遺伝子型ＲＳウイルス（ＯＮ１）の増殖能の解析

2016 Fiscal Year Annual Research Report

• Project/Area Number: 15J05618
• Research Institution: Tohoku University
• Principal Investigator: MALASAO RUNGNAPA 東北大学, 医学系研究科, 特別研究員(DC2)
• Project Period (FY): 2015-04-24 – 2017-03-31
• Keywords: Respiratory syncytial / Reverse genetics / NA1 / ON1

Outline of Annual Research Achievements

I analyzed molecular characterization of HRSV in Biliran Island, Philippines over three seasons in 2013, 2014, and 2015. Nasopharyngeal swabs were collected from hospitalized children with severe pneumonia at the Biliran Provincial Hospital. Samples were screened by using real-time polymerase chain reaction (PCR). Genotypes were determined using conventional PCR and sequencing of the 2nd hypervariable region (HVR) of the G gene. Of 1,240 sample tested, 356 (28.7%) were positive for HRSV including 183 (51.4%) HRSV-A and 173 (48.6%) HRSV-B. HRSV-A were further divided into two genotypes; NA1 and ON1. Both NA1 and ON1 were co-circulating in 2013, only ON1 remained to be circulating in 2014. A novel ON1 variant, which was phylogenetically distinct from other ON1 strains, was detected in 2014. These novel ON1 viruses possess three unique amino acid substitutions (K212R, K213G, and K223G) in the 2nd HVR of the G gene, which had not been found in other countries. All HRSV-B viruses were identified as genotype BA9 except two samples identified as GB2. Both HRSV-A and -B were co-circulating in 2013 and 2014 seasons, but most of HRSV detected in 2015 season were HRSV-B. Most of amino acid sites of the 2nd HVR of the G gene were under purifying/negative selection. This study can build on the molecular characterization to contribute the advance of molecular genetics on HRSV in the Philippines. Moreover, I made the manuscript of complete genome sequences of HRSV-A in the Philippines that I did last year.

Research Progress Status

28年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

28年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] Research Institute for Tropical Medicine(Philippines)
  • Country Name: Philippines
  • Counterpart Institution: Research Institute for Tropical Medicine
• [Journal Article] Differences in viral load among human respiratory syncytial virus genotypes in hospitalized children with severe acute respiratory infections in the Philippines (2016)
  • Author(s): Kadji FM, Okamoto M, Furuse Y, Tamaki R, Suzuki A, Lirio I, Dapat C, Malasao R, Saito M, Pedrera-Rico GA, Tallo V, Lupisan S, Saito M, Oshitani H.
  • Journal Title: Virol J Volume: 13 Pages: 113
  • DOI: 10.1186/s12985-016-0565-8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Complete genome analysis of a rare G12P[6] rotavirus isolated in Thailand in 2012 reveals a prototype strain of DS-1-like constellation (2016)
  • Author(s): Saikruang W, Khamrin P, Malasao R, Kumthip K, Ushijima H, Maneekarn N.
  • Journal Title: Virus Res Volume: 224 Pages: 38-45
  • DOI: 10.1016/j.virusres.2016.08.002
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Molecular epidemiology of HRSV in Biliran, Philippines (2016)
  • Author(s): Malasao R, Okamoto M, Furuse Y, Dapat C, Saito M, Saito-Obata M, Tamaki R, Pedrera-Rico GA, Segubre-Mercado E, Lupisan S, Oshitani H
  • Organizer: The 64th Annual Meeting of the Japanese Society for Virology
  • Place of Presentation: Sapporo Convention Center, Sapporo(Japan)
  • Year and Date: 2016-10-23 – 2016-10-25
• [Remarks] 東北大学大学院医学系研究科 微生物学分野
  • URL: http://www.virology.med.tohoku.ac.jp/
• [Remarks] Tohoku-RITM Collaborating Research Center
  • URL: http://www.virology.med.tohoku.ac.jp/project/jgrid/jgrid.html