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In a recent IUIS Webinar, Eric Vivier presented data on longitudinal analysis of immune responses in the blood and bronchoalveolar lavage fluid (BALF) of patients at various stages of COVID-19 severity: paucisymptomatic, pneumonia and acute respiratory distress syndrome (ARDS). Anti-C5aR1 therapeutic monoclonal antibodies, Avdoralimab, prevented C5a-mediated human myeloid cell recruitment and activation...

Dexamethasone is a corticosteroid that was put into clinical trial to identify whether it could modulate immune-mediated lung injury and reduce progression to respiratory failure and death in COVID-19 patients. In a pre-peer reviewed paper, preliminary results of the RECOVERY trial was reported. This was a randomized trial comparing a range of possible treatments with usual care...

A recent publication in Nature Medicine investigated the acute antibody response to SARS-CoV-2 infection. Virus-specific IgG and IgM were measured in serum samples from asymptomatic and symptomatic individuals. In the asymptomatic group, 81.1% tested positive for IgG, and 83.8% of the symptomatic group tested positive for IgG approximately 3–4 weeks after exposure.

Authors in a pre-peer reviewed article established a quantitative RT-PCR assay for SARS-CoV-2 in breastmilk with a limit of detection of 250 copies per mL. They applied this to a series of 64 serial breastmilk samples from 18 SARS-CoV-2-infected women and found viral RNA in only one sample. After viral culture, they found the sample to be replication-incompetent and concluded that breast milk is not a source of SARS-CoV-2 infection to infants.

A recent study in the New England Journal of Medicine made a genome wide association analysis of 1980 patients with varying severities of COVID-19 to identify genetic factors associated with disease. The authors detected cross-replicating associations with rs11385942 at locus 3p21.31 and with rs657152 at locus 9q34.2. Locus 3p21.3 spans the genes SLC6A20, LZTFL1...

Researchers have developed a “pilot-scale production of a purified inactivated SARS-CoV-2 virus vaccine candidate (PiCoVacc), which induced SARS-CoV-2-specific neutralizing antibodies in mice, rats and non-human primates”. The induced antibodies neutralized 10 representative SARS-CoV-2 strains which suggests that there may be a possible broader neutralizing ability. “Three immunizations using two different doses...

Lisa Ng in a recent IUIS webinar, “provides an overview of the pathophysiology of SARS-CoV-2 infection. She describes its interaction with the immune system and the subsequent contribution of dysfunctional immune responses to disease progression”. Highlights of her webinar include:Identification of two B cell epitopes S14P5 and S21P that induce neutralising Ab in COVID-19 patients...

IUIS webinar by Donna Farber described respiratory immunity associated with COVID-19. Highlights from her talk include: The importance of T cell differentiation and tissue localisation, particularly development of tissue resident memory (TRM) cells, in the maintenance of protective immunity against respiratory viruses. Research by Zhao et al., that demonstrate that airway TRM CD4 T cells play...

Identification of immunogenic SARS-CoV-2 epitopes and peptides are critical to the design of new diagnostics and potential vaccines. Researchers from A*Star and other Singaporean research institutions aimed to identify potential B cell epitopes recognised by Abs from convalescent COVID-19 patients. Using neutralisation assays researchers identified two immunodominant epitopes S14P5 and S21P...

Developing neutralising antibodies that target the SARS-CoV-2 Spike protein, has been highlighted as a potential strategy for an effective COVID-19 vaccine. Pre-clinical studies have demonstrated the ability to induce high levels of SARS-CoV-2 spike protein-specific neutralising Abs (nAbs) in animal models. However, adenovirus-based vaccines such as the ChAdOx1 and a human adenovirus 5...