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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22283000

RESUMO

The Omicron era of the COVID-19 pandemic commenced at the beginning of 2022 and whilst it started with primarily BA.1, it was latter dominated by BA.2 and related sub-lineages. Over the course of 2022, we monitored the potency and breadth of antibody neutralization responses to many emerging variants at two levels: (i) we tracked over 400,000 U.S. plasma donors over time through various vaccine booster roll outs and Omicron waves using antibody pools. (ii) we mapped the antibody response at the individual level using blood from strigently curated vaccine and convalescent cohorts. In pooled antibody samples, we observed the maturation of neutralization breadth to Omicron variants over time through continuing vaccine and infection waves. Importantly, in many cases we observed increased antibody breadth to variants that were yet to be in circulation. Resolution of viral neutralisation at the cohort level supported equivalent coverage across prior and emerging variants with emerging isolates BQ.1.1, XBB.1 and BR.2.1 the most evasive. Further, these emerging variants were resistant to Evusheld, whilst neutralization resistance to Sotrovimab was restricted to BQ.1.1 and further supported by lack of Spike glycoprotein binding to this variant. An outgrowth advantage through better utilization of TMPRSS2 was observed across BQ lineages and not those derived from BA.2.75. We conclude at this current point in time that variants derived from BQ lineages can evade antibodies at levels equivalent to their most evasive BA.2.75 counterparts but sustain an entry phenotype that would promote an additional outgrowth advantage.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265549

RESUMO

Chronic lymphocytic leukemia (CLL) is associated with immunocompromise and high risk of severe COVID-19 disease and mortality. Monoclonal B-Lymphocytosis (MBL) patients also have immune impairment. We evaluated humoral and cellular immune responses in 181 patients with CLL (160) and MBL (21) to correlate failed seroconversion (<50AU/mL SARS-CoV-2 II IgG assay, antibody to spike protein, Abbott Diagnostics) following each of 2 vaccine doses with clinical and laboratory parameters. Following first and second doses, 79.2% then 45% of CLL, and 50% then 9.5% of MBL respectively remained seronegative, indicating 2 vaccine doses are crucial. There was significant association between post-dose 2 antibody level with pre-vaccination reduced IgM (p<0.0001), IgG2 (p<0.035), IgG3 (p<0.046), and CLL therapy within 12 months (p<0.001) in univariate analysis. By multivariate analysis, reduced IgM (p<0.0002) and active therapy (p<0.0002) retained significance. There was no significant correlation with age, gender, CLL duration, IgG, IgA or lymphocyte subsets. Anti-spike protein levels varied widely and were lower in CLL, than MBL, and both lower than normal donors. Neutralization activity showed anti-spike levels <1000AU/mL were usually negative for both an early viral clade and the contemporary Delta variant. There were 72.9% of CLL and 53.3% of MBL who failed to reach anti-spike levels >1000AU/mL. In a representative subset of 32 CLL patients, 80% had normal T-cell responses by IFN{gamma} and IL-2 FluoroSpot assay. Failed seroconversion occurred in 36.6%% of treatment-naive patients, 52.9% treatment-naive with reduced IgM, 78.1% on therapy, and 85.7% on ibrutinib. Vaccination failure is very common in CLL, including early-stage disease. 6 Key Novel FindingsO_LIComparison CLL vs MBL vs normal - 45% of CLL and 9.5% of MBL fail to seroconvert with 2 doses of COVID-19 vaccine C_LIO_LINeutralization assay - SARS CoV-2 IgG levels <1000 AU/mL rarely associated with neutralization activity. C_LIO_LICOVID-19-specific T-cell function by FluoroSpot IFN-g and IL-2 production C_LIO_LIIgG, A, M class and IgG subclass: correlations by univariate and multivariate analysis - IgM (OR 7.29 p<0.0001), IgG2 and IgG3 subclass univariate significance C_LIO_LICorrelation with therapy - ICT, targeted therapies, and those on Ig replacement C_LIO_LIHigh risk of vaccination failure for all CLL, including early-stage disease, and MBL C_LI Key PointsCLL and MBL show significantly impaired anti-spike antibody, viral neutralization, with cellular immune response to COVID-19 vaccination Failure to seroconvert is associated with low IgM, IgG2, IgG3, and recent therapy; many CLL and MBL patients remain COVID-19 vulnerable

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