Profs Present...The Tell-tale Sign of Antibodies: Determining COVID-19 Immunity with Blood Testing with Professor Brian Dixon

Wednesday, September 23, 2020 12:10 pm - 12:10 pm EDT (GMT -04:00)

COVID-19 has brought disease and mortality at levels not seen from a respiratory virus for over 100 years. Immune responses to this virus, which can infect several different tissues, are poorly understood, including the role of antibodies in resolving the infection. In March 2020, we reoriented our lab to develop Enzyme-Linked ImmunoSorbent Assays (ELISA) for human antibody isotypes IgM, IgG and IgA produced in response to the SARS-CoV-2 spike protein. To date we have analyzed samples from 114 patients, including both PCR positive and PCR negative individuals. The initial blind test of 15 positive and 15 negative individuals showed that our assay reliable detected antibody titres in positive cases and not in negative individuals. A larger study of 84 patients showed that there is a diversity of individual antibody responses, with individuals developing IgG responses within 4 days while others take at least 58 days. While some patients seroconvert and lose IgM titres, patients who develop IgG responses can show reduced titres as early as 55 days, or maintain high titres until 108 days, although no patients have completely lost IgG responses to date. We are working to pair these observations with clinical data and outcomes to see patterns in responses that may guide treatments.

Brian Dixon

When the University of Waterloo's research labs shut down for quarantine, biology professor Brian Dixon pivoted some of his research away from blood testing in fish, into looking at blood testing in humans. Instead of sitting around and waiting for his labs to open again, Dixon wanted to use his time and knowledge of biology and immunology to contribute to the global need for understanding and overcoming COVID-19.

Professor Dixon is a Canadian Research Chair (CRC), member of the Water Institute, the Centre for Bioengineering and Biotechnology (CBB) and has been a faculty member in the Dept. of Biology since 2000

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This talk is co-hosted by:

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