SARS-CoV-2-specific memory B cells can persist in the elderly despite loss of neutralising antibodies

10.1101/2021.05.30.446322

bioRxiv

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This research has not been peer-reviewed, and has been posted on pre-print repository bioRxiv. This is a preliminary report that should not be regarded as conclusive, guide clinical practice/health-related behaviour, or be reported in news media as established information.


Abstract

Memory B cells (MBC) can provide a recall response able to supplement waning antibodies with an affinity-matured response better able to neutralise variant viruses. We studied a cohort of vulnerable elderly care home residents and younger staff, a high proportion of whom had lost neutralising antibodies (nAb), to investigate their reserve immunity from SARS-CoV-2-specific MBC. Class-switched spike and RBD-tetramer-binding MBC with a classical phenotype persisted five months post-mild/asymptomatic SARS-CoV-2 infection, irrespective of age. Spike/RBD-specific MBC remained detectable in the majority who had lost nAb, although at lower frequencies and with a reduced IgG/IgA isotype ratio. Functional spike/S1/RBD-specific recall was also detectable by ELISpot in some who had lost nAb, but was significantly impaired in the elderly, particularly to RBD. Our findings demonstrate persistence of SARS-CoV-2-specific MBC beyond loss of nAb, but highlight the need for careful monitoring of functional defects in RBD-specific B cell immunity in the elderly.

Author list:

Anna Jeffery-Smith, Alice R Burton, Sabela Lens, Chloe Rees-Spear, Monika Patel, Robin Gopal, Luke Muir, Felicity Aiano, Katie J Doores, J. Yimmy Chow, Shamez N Ladhani, Maria Zambon, Laura E McCoy, Mala K Maini