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1.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-496062

RESUMEN

BackgroundHIV infection dysregulates the B cell compartment, affecting memory B cell formation and the antibody response to infection and vaccination. Understanding the B cell response to SARS-CoV-2 in people living with HIV (PLWH) may explain the increased morbidity, reduced vaccine efficacy, reduced clearance, and intra-host evolution of SARS-CoV-2 observed in some HIV-1 coinfections. MethodsWe compared B cell responses to COVID-19 in PLWH and HIV negative (HIV-ve) patients in a cohort recruited in Durban, South Africa, during the first pandemic wave in July 2020 using detailed flow cytometry phenotyping of longitudinal samples with markers of B cell maturation, homing and regulatory features. ResultsThis revealed a coordinated B cell response to COVID-19 that differed significantly between HIV-ve and PLWH. Memory B cells in PLWH displayed evidence of reduced germinal center (GC) activity, homing capacity and class-switching responses, with increased PD-L1 expression, and decreased Tfh frequency. This was mirrored by increased extrafollicular (EF) activity, with dynamic changes in activated double negative (DN2) and activated naive B cells, which correlated with anti-RBD-titres in these individuals. An elevated SARS-CoV-2 specific EF response in PLWH was confirmed using viral spike and RBD bait proteins. ConclusionsDespite similar disease severity, these trends were highest in participants with uncontrolled HIV, implicating HIV in driving these changes. EF B cell responses are rapid but give rise to lower affinity antibodies, less durable long-term memory, and reduced capacity to adapt to new variants. Further work is needed to determine the long-term effects of HIV on SARS-CoV-2 immunity, particularly as new variants emerge. FundingThis work was supported by a grant from the Wellcome Trust to the Africa Health Research Institute (Wellcome Trust Strategic Core Award [grant number 201433/Z/16/Z]). Additional funding was received from the South African Department of Science and Innovation through the National Research Foundation (South African Research Chairs Initiative, [grant number 64809]), and the Victor Daitz Foundation.

2.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21263564

RESUMEN

Characterizing SARS-CoV-2 evolution in specific geographies may help predict the properties of variants coming from these regions. We mapped neutralization of a SARS-CoV-2 strain that evolved over 6 months from the ancestral virus in a person with advanced HIV disease. Infection was before the emergence of the Beta variant first identified in South Africa, and the Delta variant. We compared early and late evolved virus to the ancestral, Beta, Alpha, and Delta viruses and tested against convalescent plasma from ancestral, Beta, and Delta infections. Early virus was similar to ancestral, whereas late virus was similar to Beta, exhibiting vaccine escape and, despite pre-dating Delta, strong escape of Delta-elicited neutralization. This example is consistent with the notion that variants arising in immune-compromised hosts, including those with advanced HIV disease, may evolve immune escape of vaccines and enhanced escape of Delta immunity, with implications for vaccine breakthrough and reinfections. HighlightsO_LIA prolonged ancestral SARS-CoV-2 infection pre-dating the emergence of Beta and Delta resulted in evolution of a Beta-like serological phenotype C_LIO_LISerological phenotype includes strong escape from Delta infection elicited immunity, intermediate escape from ancestral virus immunity, and weak escape from Beta immunity C_LIO_LIEvolved virus showed substantial but incomplete escape from antibodies elicited by BNT162b2 vaccination C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/21263564v2_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@1194bfdorg.highwire.dtl.DTLVardef@1cbe318org.highwire.dtl.DTLVardef@aa74f8org.highwire.dtl.DTLVardef@e57969_HPS_FORMAT_FIGEXP M_FIG C_FIG

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