Apr 01, 2022
RPG Seminar (2022-04-01)
Date: Friday, 1 April 2022
Time: 5:00 p.m. - 6:00 p.m.
Meeting ID: 922 5574 1566
Presenter: Mr. Xuansheng LIN, PhD candidate
Primary Supervisor: Prof. Jiandong HUANG
Presentation Title: Development of live attenuated vaccine against Staphylococcus aureus by synthetic biology approach
Abstract: Staphylococcus aureus (S. aureus) is an opportunistic pathogen which is capable of causing various infection across a broad spectrum of tissues. Currently, treatment of S. aureus infection in clinical settings heavily relies on the use of antibiotics, thus leads to prevalence of multidrug resistant S. aureus strain. To efficiently combat the prevalence of multidrug resistant, vaccine development represents an effective approach. Unfortunately, no vaccines against S. aureus are approved by regulatory authorities up to date. Previous attempts to develop S. aureus vaccines mainly focused on employing single or combination of simple components, such as bacteria derived proteins and polysaccharides. Here, we present a synthetic biological approach to design a live attenuated S. aureus vaccine. In current project, we constructed a live attenuated vaccine candidate by knocking out adenosine synthase A (adsA), capsule biosynthesis gene cluster (CP), D-alanine aminotransferase (dat) and glutamate racemase (murI) coding genes in S. aureus Newman strain. Protective effect of the candidate was evaluated in survival study, mice vaccinated by the candidate had a significantly higher survival rate comparing to controls. This result indicates that live attenuated Staphylococcus aureus can serve as a promising vaccine candidate.
Presenter: Mr. Chon Phin ONG, PhD candidate
Primary Supervisor: Prof. Dong-Yan JIN
Presentation Title: Development of a 2’-O-Methyltransferase Defective SARS-CoV-2 mutant as a candidate live attenuated vaccine
Abstract: Prevention is better than cure. Over the years, vaccines have been proven successful in averting pathogen-induced illnesses. Among various types of vaccines, live attenuated vaccines were outstanding in stimulating the immune system and concurrently providing long lasting immunity to the host. Presently, COVID-19 remains devastating despite two years since its emergence, resulted from the adaptation mutation capability of SARS-CoV-2 to facilitate immune evasion. Here, we generated an impaired 2’-O-Methyltransferase (NSP16) mutant virus, designated as d16. In vivo studies in Syrian hamsters and transgenic mice have revealed severe attenuation of d16 in terms of pathogenicity. Single intranasal administration in Syrian hamsters has resulted in sterilising immunity in respiratory tracts and concomitantly prevented viral transmission in a contact-based transmission model. In summary, d16 potentially serves as a new platform in prospective development of live attenuated vaccines. Further modifications could be introduced to d16 to improve safety, immunogenicity and efficacy.
ALL ARE WELCOME
Should you have any enquiries, please feel free to contact Miss Cynthia Cheung at 3917 9748.