v25i2

and compared with SARS-CoV, providing new insights on COVID-19’s reduced disease severity, mortality and diarrhoea incidence, but higher transmissibility. » The screening of broad-spectrum host- based antivirals identified interferon and lipogenesis pathways as a main treatment option for COVID-19. » Human brain organoids and human neural progenitor cells were another part of our testing kit and we were the first to discover that SARS-CoV-2 could infect these, too, and thus enter the human central nervous system. » We provided the first comprehensive cell- line tropism report, demonstrating the tissue and species tropism of SARS-CoV-2. » The human immune response to SARS-CoV-2 has also been probed. One study showed that the levels of bacterial products released in infected human plasma correlated with disease severity and that the virus evaded the innate host responses normally marshalled to combat virus infections. » Potent neutralising antibodies against multiple epitopes on the SARS-CoV-2 spike protein were identified as promising monoclonal antibodies for therapeutic/ prophylactic agents against SARS-CoV-2. » Stronger antibody responses were also found to be associated with more severe COVID-19, including the neutralising antibody response. Systematic neutralising antibodies may be insufficient for inhibiting SARS-CoV-2 infection at the mucosal portal of viral entry. Acute SARS-CoV-2 infection also results in broad immune cell reduction and functional impairment, including both dendritic cells and T cells. While neutralising antibodies are rapidly generated, antigen-specific T cells are delayed at the acute stage of infection. » We identified two novel virus protein targets, ORF8 and ORF3b, which facilitate antibody testing for COVID-19. Treatment and vaccine development » A finding that acute SARS-CoV-2 infection impaired human immune defences pointed to treatment that could jump-start the immune response, in particular the early use of drugs with immune-boosting and antiviral properties. » An international study involving HKUMed also identified 13 existing antiviral drugs with effective enough concentrations to be potential therapeutic treatments for COVID-19 patients, from a field of 12,000 such drugs. The advantage of this approach is that many of these drugs have already been tested in clinical settings for other purposes. HKUMed researchers found that acute SARS- CoV-2 infection was shown to impair human immune defences, with significant implications for viral transmission, disease severity and vaccine research. 19