New insights into formation, durability and plasticity of human memory B cells from allergy and COVID-19

Host: Dr Julia Ellyard

Abstract

From birth onwards, humans are exposed to a barrage of microorganisms, generating immunological memory. In healthy individuals, this extensive immune memory provides immunity against disease on subsequent re-exposure. However, impaired or dysfunctional immune B-cell memory (Bmem) underlies disorders such as immunodeficiency, autoimmunity and allergy, as well as poor responses to multiple vaccines for infectious diseases. A historical barrier is the detection of rare antigen-specific cells within the total pool of Bmem.

In my group, we have established a pipeline for production of recombinant proteins that can be used in high-parameter flowcytometry to detect antigen-specific Bmem. Through application of this technology to carefully-recruited patient cohorts, we aim to provide a deeper understanding into the formation and durability of newly-formed Bmem, as well as their plasticity upon booster immunisation or allergen immunotherapy.

In this seminar, I will present our findings on SARS-CoV-2 infection and COVID-19 vaccination, particularly the rapid formation and durability for at least 8 months, and differences between mRNA (Pfizer) and adenoviral vector (AstraZeneca) vaccination, as well as 3^rd dose boosters.

Furthermore, I will present on the transcriptional and immunophenotypic diversity of antigen-specific Bmem in patients with allergic disease, as well as the effects of allergen-immunotherapy on these pathogenic cells.

Our ultimate aim is to translate these biological insights into optimised vaccination strategies and immunotherapies.

Biography

Prof Menno van Zelm obtained his PhD from the Erasmus University in Rotterdam, the Netherlands (2007), and held postdoc positions at the University of California San Diego (USA) and the Erasmus MC (the Netherlands), prior to becoming Lab Head at the Erasmus MC (2010). In 2015, he was recruited to Monash University and the Alfred Hospital where he is currently Deputy Head (research) of the Department of Immunology.

Dr. van Zelm has received continuous fellowship support in the Netherlands and Australia (current NHMRC Senior Research Fellowship). In 2010, he received the Heineken Young Scientists Award from the Royal Netherlands Academy of Sciences (KNAW). Menno van Zelm is chair of the President of HCDM, the organisation that assigns CD Nomenclature, and founding director of the JMF Centre for Immunodeficiencies in Melbourne. He heads the Allergy and Clinical Immunology laboratory, has published >160 papers in international peer-reviewed journals, and is co-inventor on several patent applications. In 2019, he developed technology to detect antigen-specific B-cells in collaboration with Prof Robyn O’Hehir (Alfred Health) and Prof P. Mark Hogarth (Burnet Institute), and currently applies this to evaluate B-cell memory in allergies (NHMRC Ideas grant) and infectious disease, including SARS-CoV2 (MRFF grant).