Date: Wednesday, 2 June 2021

Venue: Cheung Kung Hai Lecture Theatre 1, G/F, William M.W. Mong Block, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong

Time: 5:00 p.m. - 6:00 p.m.

5:00 p.m.

Speaker: Dr. Menglong HU (Post-doctoral Fellow)
Primary Supervisor: Prof. Ren SUN
Presentation Title: Tailor-made monobodies recognizing the conserved epitopes of SARS-CoV-2 N antigen applicable to the broad COVID-19 diagnosis
Abstract: The coronavirus disease 2019 (COVID-19) pandemic has imposed a severe threat to public health. As vaccination is gradually applied worldwide, early detection of viral antigens has become more preponderant than serological assays to facilitate COVID-19 diagnosis. By means of in vitro maturation including mRNA display and high-throughput library, we obtained two fibronectin-based affinity-enhanced antibody mimetics (monobodies) against the SARS-CoV-2 nucleocapsid (N) protein, termed NN2 and NC2.  We resolved the crystal structures of NN2 complexed with N-NTD and NC2 complexed with N-CTD. Of particular note is the high conservation of interfaces of N protein which are engaged in binding to NN2 or NC2, suggesting the high resistance of NN2-N and NC2-N interactions to naturally occurring mutations of SARS-CoV-2. Using this pair of monobodies, we developed enzyme-linked immunosorbent assays (ELISAs) and lateral-flow immunoassays (LFAs) for viral antigen detection. It was shown that N in the viral culture supernatant could be detected. We also presented the potential of monobody-based ELISA for diagnosis with patient samples.

5:30 p.m. 

Speaker: Dr. Sze Wai FUNG (Post-doctoral Fellow)
Primary Supervisor: Prof. George Sai Wah TSAO
Presentation Title: In vivo selection of nasopharyngeal carcinoma cells with persistent latent EBV infection
Abstract: Undifferentiated nasopharyngeal carcinoma (NPC) is strongly associated with latent EBV infection. Persistent latent EBV infection is believed to play a critical role in the pathogenesis of NPC. Yet, although EBV is detected in almost all malignant cells in clinical specimens and patient-derived xenografts, it is often loss during prolonged culture in vitro. We investigated the impact of in vivo growth conditions in supporting the maintenance of EBV latency in NPCs. EBV^+ve NPC43 cell culture re-established from tumor xenografts showed increase in EBV^+ve cell population and increase in EBV copy number per NPC cell, suggesting selection of EBV^+ve cells over EBV^-ve NPC cells in vivo. We demonstrated the importance of the interplay between in vivo tumor microenvironment, tumor cells and latent EBV infection, which would be important for the development of novel therapeutics against EBV-associated NPC.

ALL ARE WELCOME

Should you have any enquiries, please feel free to contact Miss River Wong at 3917 9216.