Project 3: Attenuating RSV with Mutations in Its Methyltransferase PI: Jianrong Li, DVM, PhD Abstract: Human respiratory syncytial virus (RSV) is the leading causative agent of pediatric respiratory tract disease worldwide. Despite major efforts, there is no vaccine currently available to combat this virus. Live attenuated vaccines are the most promising vaccine candidates for RSV. However, it has been a challenge to identify an attenuated RSV strain that has an optimal balance between attenuation and immunogenicity. The objectives of this project are to rationally attenuate RSV by targeting the viral mRNA cap methyltransferase (MTase) and to develop MTase-defective viruses as novel live attenuated vaccine candidates for RSV. The RSV mRNA cap structure is methylated at the guanine-N-7 (G-N-7) and ribose 2?-O positions by a single conserved region VI (CR-VI) located in the large (L) polymerase protein. Amino acid residues essential for G-N-7 and/or 2?-O MTase activities will be characterized and will be introduced into an infectious cDNA clone of RSV. Recombinant RSVs defective in G-N-7 and/or 2?-O MTase activities will be recovered, and their attenuation in cell culture will be characterized. These recombinant viruses will be tested for their infectivity and ability to spread in primary, well differentiated, human airway epithelial (HAE) cultures. Next, their replication, pathogenesis, immunogenicity, and capacity to induce protection will be examined in cotton rats, the best available small animal model for RSV. By adding interferon-producing NS1 mutations (Project 1) and ?repaired G? mutations (Project 2) to the most promising MTase mutations in L to RSV, we expect that we will generate a panel of ideal RSV vaccine strains that grow well in Vero cells, are attenuated in vitro and in vivo, genetically stable, and highly immunogenic. These new, improved live RSV vaccine candidates can then be used for future trials in nonhuman primates.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZAI1)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Nationwide Children's Hospital
United States
Zip Code
Hussain, Syed-Rehan A; Mejias, Asuncion; Ramilo, Octavio et al. (2018) Post-viral atopic airway disease: pathogenesis and potential avenues for intervention. Expert Rev Clin Immunol :1-10
Garcia-Mauriño, Cristina; Moore-Clingenpeel, Melissa; Wallihan, Rebecca et al. (2018) Discharge Criteria for Bronchiolitis: An Unmet Need. Pediatr Infect Dis J 37:514-519
Wang, Yilong; Liu, Rongxian; Lu, Mijia et al. (2018) Enhancement of safety and immunogenicity of the Chinese Hu191 measles virus vaccine by alteration of the S-adenosylmethionine (SAM) binding site in the large polymerase protein. Virology 518:210-220
Li, Anzhong; Yu, Jingyou; Lu, Mijia et al. (2018) A Zika virus vaccine expressing premembrane-envelope-NS1 polyprotein. Nat Commun 9:3067
Korppi, Matti (2018) Discharge Criteria for Bronchiolitis: Does Age Matter? Pediatr Infect Dis J 37:e350
Garcia-Mauriño, Cristina; Moore-Clingenpeel, Melissa; Ramilo, Octavio et al. (2018) Re: ""Discharge Criteria for Bronchiolitis: Does Age Matter?"" Pediatr Infect Dis J 37:e350-e351
Grieves, Jessica L; Yin, Zhiwei; Garcia-Sastre, Adolfo et al. (2018) A viral-vectored RSV vaccine induces long-lived humoral immunity in cotton rats. Vaccine 36:3842-3852
Garcia-Mauriño, Cristina; Moore-Clingenpeel, Melissa; Thomas, Jessica et al. (2018) Viral Load Dynamics and Clinical Disease Severity in Infants with Respiratory Syncytial Virus Infection. J Infect Dis :
Mazur, Natalie I; Higgins, Deborah; Nunes, Marta C et al. (2018) The respiratory syncytial virus vaccine landscape: lessons from the graveyard and promising candidates. Lancet Infect Dis 18:e295-e311
Hicks, Stephanie N; Chaiwatpongsakorn, Supranee; Costello, Heather M et al. (2018) Five Residues in the Apical Loop of the Respiratory Syncytial Virus Fusion Protein F2 Subunit Are Critical for Its Fusion Activity. J Virol 92:

Showing the most recent 10 out of 21 publications