Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22276253

RESUMO

ImportancePeople living with multiple sclerosis (MS) and other disorders treated with immunomodulatory therapies remain concerned about suboptimal responses to coronavirus disease 2019 (COVID-19) vaccines. Important questions persist regarding immunological response to third vaccines, particularly with respect to newer virus variants. ObjectiveEvaluate humoral and cellular immune responses to third COVID-19 vaccine dose in people on anti-CD20 therapy and sphingosine 1-phosphate receptor (S1PR) modulators, including Omicron-specific assays. DesignObservational study evaluating immunological response to third COVID-19 vaccine dose in volunteers treated with anti-CD20 agents, S1PR modulators, and healthy controls. Neutralizing antibodies against USA-WA1/2020 (WA1) and B.1.1.529 (BA.1) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were measured before and after third vaccine. Cellular responses to spike peptide pools generated from WA1 and BA.1 were evaluated. SettingMount Sinai Hospital ParticipantsPeople treated with anti-CD20 therapy or S1PR modulators and healthy volunteers ExposureTreatment with anti-CD20 therapy, S1PR modulator, or neither Main outcomes and measuresSerum neutralizing antibodies and ex vivo T cell responses against SARS-CoV-2 antigens. ResultsThis cohort includes 25 participants on anti-CD20 therapy, 12 on S1PR modulators, and 14 healthy controls. Among those on anti-CD20 therapy, neutralizing antibodies to WA1 were significantly reduced compared to healthy controls (ID50% GM post-vaccination of 8.1 {+/-} 2.8 in anti-CD20 therapy group vs 452.6 {+/-} 8.442 healthy controls, P<0.0001) and neutralizing antibodies to BA.1 were below the threshold of detection nearly universally. However, cellular responses, including to Omicron-specific peptides, were not significantly different from controls. Among those on S1PR modulators, neutralizing antibodies to WA1 were detected in a minority, and only 3/12 had neutralizing antibodies just at the limit of detection to BA.1. Cellular responses to Spike antigen in those on S1PR modulators were reduced by a factor of 100 compared to controls (median 0.0008% vs. 0.08%, p<0.001) and were not significantly "boosted" by a third injection. Conclusions and RelevanceParticipants on immunomodulators had impaired antibody neutralization capacity, particularly to BA.1, even after a third vaccine. T cell responses were not affected by anti-CD20 therapies, but were nearly abrogated by S1PR modulators. These results have clinical implications warranting further study.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22275533

RESUMO

AO_SCPLOWBSTRACTC_SCPLOWPersistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have been reported in immune-compromised individuals and people undergoing immune-modulatory treatments. Although intrahost evolution has been documented, to our knowledge, no direct evidence of subsequent transmission and stepwise adaptation is available. Here we describe sequential persistent SARS-CoV-2 infections in three individuals that led to the emergence, forward transmission, and continued evolution of a new Omicron sublineage, BA.1.23, over an eight-month period. The initially transmitted BA.1.23 variant encoded seven additional amino acid substitutions within the spike protein (E96D, R346T, L455W, K458M, A484V, H681R, A688V), and displayed substantial resistance to neutralization by sera from boosted and/or Omicron BA.1-infected study participants. Subsequent continued BA.1.23 replication resulted in additional substitutions in the spike protein (S254F, N448S, F456L, M458K, F981L, S982L) as well as in five other virus proteins. Our findings demonstrate that the Omicron BA.1 lineage can diverge further from its already exceptionally mutated genome during persistent infection in more than one host, and also document ongoing transmission of these novel variants. There is an urgent need to implement strategies to prevent prolonged SARS-CoV-2 replication and to limit the spread of newly emerging, neutralization-resistant variants in vulnerable patients.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22273938

RESUMO

BackgroundBreakthrough infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant (B.1.1.529) has occurred in populations with high vaccination rates. These infections are due to sequence variation in the spike protein leading to a reduction in protection afforded by the current vaccines, which are based on the original Wuhan-Hu-1 strain, or by natural infection with pre-Omicron strains. MethodsIn a longitudinal cohort study, pre-breakthrough infection sera for Omicron breakthroughs (n=12) were analyzed. Assays utilized include a laboratory-developed solid phase binding assay to recombinant spike protein, a commercial assay to the S1 domain of the spike protein calibrated to the World Health Organization (WHO) standard, and a commercial solid-phase surrogate neutralizing activity (SNA) assay. All assays employed spike protein preparations based on sequences from the Wuhan-Hu-1 strain. Participant demographics and clinical characteristics were captured. ResultsPre-breakthrough binding antibody (bAB) titers ranged from 1:800-1:51,200 for the laboratory-developed binding assay, which correlated well and agreed quantitatively with the commercial spike S1 domain WHO calibrated assay. SNA was detected in 10/12 (83%) samples. ConclusionsNeither high bAB nor SNA were markers of protection from Omicron infection/re-infection. Laboratory tests with antigen targets based on Wuhan-Hu-1 may not accurately reflect the degree of immune protection from variants with significant spike protein differences. Omicron breakthrough infections are likely due to high sequence variation of the spike protein and reflect incomplete immune protection from previous infection with strains that preceded Omicron or with vaccinations based on the original Wuhan-Hu-1 strain.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22273914

RESUMO

Two messenger RNA (mRNA)-based vaccines are widely used globally to prevent coronavirus disease 2019 (COVID-19). Both vaccine formulations contain PEGylated lipids in their composition, in the form of polyethylene glycol [PEG] 2000 dimyristoyl glycerol for mRNA-1273, and 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide for BNT162b2. It is known that some PEGylated drugs and products for human use that contain PEG, are capable of eliciting immune responses, leading to detectable PEG-specific antibodies in serum. In this study, we determined if any of the components of mRNA-1273 or BNT162b2 formulations elicited PEG-specific antibody responses in serum by enzyme linked immunosorbent assay (ELISA). We detected an increase in the reactivity to mRNA vaccine formulations in mRNA-1273 but not BNT162b2 vaccinees sera in a prime-boost dependent manner. Furthermore, we observed the same pattern of reactivity against irrelevant lipid nanoparticles from an influenza virus mRNA formulation and found that the reactivity of such antibodies correlated well with antibody levels against high and low molecular weight PEG. Using sera from participants selected based on the vaccine-associated side effects experienced after vaccination, including delayed onset, injection site or severe allergic reactions, we found no obvious association between PEG antibodies and adverse reactions. Overall, our data shows a differential induction of anti-PEG antibodies by mRNA-1273 and BNT162b2. The clinical relevance of PEG reactive antibodies induced by administration of the mRNA-1273 vaccine, and the potential interaction of these antibodies with other PEGylated drugs remains to be explored.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...