July 2020

Corticosteroid treatment for severe COVID-19 could be regarded as a “heavy approach” to relieving the devastating effects of acute respiratory distress syndrome, and would potentially inhibit the signalling pathways leading to robust T and B cell immunity. Perhaps a more selective approach could be used to target the now known inflammatory overreaction leading to severe disease...

There are a number of studies emerging that show people infected with SARS-CoV-2 make robust T cell responses that target the spike protein, membrane antigens and nucleocapsid, with immunodominant responses against spike. With recent findings that nAbs to SARS-CoV-2 wane rapidly after peak symptoms, is there evidence that T cell memory responses linger for longer?

Professor Rudolf Valenta began his talk discussing important advances in diagnosis and therapy that have occurred in in the field of Allergy during the last couple of years. He particularly insisted on the importance of the component resolved diagnosis as a new form of modern allergy diagnosis based on the molecular aspects of allergens.

A recent correspondence in NEJM shows that antibodies to SAR-CoV-2 wane rapidly in mild disease, raising the question around the durability of potential protective immunity. Blood samples were analysed longitudinally in 30 patients with mild disease from 37 days after the onset of symptoms to a mean of 86 days (ranging from 44 to 119 days).

A recent article in Science used high dimensional cytometry to investigate the network of immune cell interactions and how they are connected in patients with COVID-19. Peripheral immune cells were analysed from 125 hospitalised patients with confirmed SARS-CoV-2 infection, 36 non-hospitalised patients who had recovered from infection and 60 healthy individuals.

Michael Reth and his team utilises CRISPR/Cas9 method to rapidly generate mutants of the Burkitt lymphoma cell line Ramos.  They used this methodology to generate Ramos B cells which lack all four components of the BCR, and can expresses the SARS-CoV-2 spike protein. Additionally, they designed a Ramos Spike flow protocol which allows them to test for...

In a pre-peer reviewed publication in MedRxiv, investigators found in critically ill COVID-19 patients that heightened extrafollicular B cells responses which lead to rapid activation of B cells resulting in high proportions of of antibody-secreting cells. However, high levels of extrafollicular B cells and SARS-CoV-2 specific antibodies, was also associated with high inflammation and poor prognosis.

This week we highlight talks by Dr David Sacks (National Institutes of Health, USA) which focused on Xenodiagnosis to evaluate transmission dynamics of visceral leishmaniasis in Bihar, India. After talking about visceral leishmanias (VL) demographical distribution and the vectors involved, Dr Sacks focused on the Kala-azar elimination program in the South Asia Region and their goal to reduce incidence...

Folegatti et al., demonstrated that vaccination with a single dose, induced robust SARS-CoV-2 spike protein-specific antibodies which peaked at day 28, and were maintained at similar levels at day 56. As expected vaccination with two doses resulted in much higher SARS-CoV-2-Ab responses than vaccination with a singe-dose. Researchers observed higher SARS-CoV-2-Ab neutralisation...

One of the hallmarks of COVID-19 immunopathology is cytokine release syndrome (CRS) and T cell dysfunction. These immune functions are partly triggered by SARS-CoV-2 activation of the mTOR pathway. Omarjee et al., describe the potential immuno-therapeutic utility of rapamycin (mTOR inhibitor) against COVID-19, a drug that is currently being tested in a phase 2 trial in USA (NCT04341675).