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Morbilliviruses are members of the family Paramyxoviridae and are known for their ability to cause systemic disease in a variety of mammalian hosts. The prototypic morbillivirus, measles virus (MeV), infects humans and still causes morbidity and mortality in unvaccinated children and young adults. Experimental infection studies in non-human primates have contributed to the understanding of measles pathogenesis. However, ethical restrictions call for the development of new animal models. Canine distemper virus (CDV) infects a wide range of animals, including ferrets, and its pathogenesis shares many features with measles. However, wild-type CDV infection is almost always lethal, while MeV infection is usually self-limiting. Here, we made five recombinant CDVs, predicted to be attenuated, and compared their pathogenesis to the non-attenuated recombinant CDV in a ferret model. Three viruses were insufficiently attenuated based on clinical signs, fatality, and systemic infection, while one virus was too attenuated. The last candidate virus caused a self-limiting infection associated with transient viremia and viral dissemination to all lymphoid tissues, was shed transiently from the upper respiratory tract, and did not result in acute neurological signs. Additionally, an in-depth phenotyping of the infected white blood cells showed lower infection percentages in all lymphocyte subsets when compared to the non-attenuated CDV. In conclusion, infection models using this candidate virus mimic measles and can be used to study pathogenesis-related questions and to test interventions for morbilliviruses in a natural host species.IMPORTANCEMorbilliviruses are transmitted via the respiratory route but cause systemic disease. The viruses use two cellular receptors to infect myeloid, lymphoid, and epithelial cells. Measles virus (MeV) remains an important cause of morbidity and mortality in humans, requiring animal models to study pathogenesis or intervention strategies. Experimental MeV infections in non-human primates are restricted by ethical and practical constraints, and animal morbillivirus infections in natural host species have been considered as alternatives. Inoculation of ferrets with wild-type canine distemper virus (CDV) has been used for this purpose, but in most cases, the virus overwhelms the immune system and causes highly lethal disease. Introduction of an additional transcription unit and an additional attenuating point mutation in the polymerase yielded a candidate virus that caused self-limiting disease with transient viremia and virus shedding. This rationally attenuated CDV strain can be used for experimental morbillivirus infections in ferrets that reflect measles in humans.
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Modelos Animais de Doenças , Vírus da Cinomose Canina , Furões , Sarampo , Infecções por Morbillivirus , Animais , Cães , Humanos , Cinomose/virologia , Vírus da Cinomose Canina/genética , Sarampo/patologia , Vírus do Sarampo/genética , Morbillivirus/genética , Infecções por Morbillivirus/patologia , Primatas , ViremiaRESUMO
Subacute sclerosing panencephalitis (SSPE) is a rare but fatal late neurological complication of measles, caused by persistent measles virus (MeV) infection of the central nervous system. There are no drugs approved for the treatment of SSPE. Here, we followed the clinical progression of a 5-year-old SSPE patient after treatment with the nucleoside analog remdesivir, conducted a post-mortem evaluation of the patient's brain, and characterized the MeV detected in the brain. The quality of life of the patient transiently improved after the first two courses of remdesivir, but a third course had no further clinical effect, and the patient eventually succumbed to his condition. Post-mortem evaluation of the brain displayed histopathological changes including loss of neurons and demyelination paired with abundant presence of MeV RNA-positive cells throughout the brain. Next-generation sequencing of RNA isolated from the brain revealed a complete MeV genome with mutations that are typically detected in SSPE, characterized by a hypermutated M gene. Additional mutations were detected in the polymerase (L) gene, which were not associated with resistance to remdesivir. Functional characterization showed that mutations in the F gene led to a hyperfusogenic phenotype predominantly mediated by N465I. Additionally, recombinant wild-type-based MeV with the SSPE-F gene or the F gene with the N465I mutation was no longer lymphotropic but instead efficiently disseminated in neural cultures. Altogether, this case encourages further investigation of remdesivir as a potential treatment of SSPE and highlights the necessity to functionally understand SSPE-causing MeV.IMPORTANCEMeasles virus (MeV) causes acute, systemic disease and remains an important cause of morbidity and mortality in humans. Despite the lack of known entry receptors in the brain, MeV can persistently infect the brain causing the rare but fatal neurological disorder subacute sclerosing panencephalitis (SSPE). SSPE-causing MeVs are characterized by a hypermutated genome and a hyperfusogenic F protein that facilitates the rapid spread of MeV throughout the brain. No treatment against SSPE is available, but the nucleoside analog remdesivir was recently demonstrated to be effective against MeV in vitro. We show that treatment of an SSPE patient with remdesivir led to transient clinical improvement and did not induce viral escape mutants, encouraging the future use of remdesivir in SSPE patients. Functional characterization of the viral proteins sheds light on the shared properties of SSPE-causing MeVs and further contributes to understanding how those viruses cause disease.
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Monofosfato de Adenosina , Alanina , Vírus do Sarampo , Sarampo , Panencefalite Esclerosante Subaguda , Proteínas Virais , Pré-Escolar , Humanos , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Alanina/administração & dosagem , Alanina/análogos & derivados , Alanina/uso terapêutico , Autopsia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Progressão da Doença , Evolução Fatal , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Sarampo/complicações , Sarampo/tratamento farmacológico , Sarampo/virologia , Vírus do Sarampo/efeitos dos fármacos , Vírus do Sarampo/genética , Vírus do Sarampo/metabolismo , Proteínas Mutantes/análise , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Qualidade de Vida , RNA Viral/análise , RNA Viral/genética , Panencefalite Esclerosante Subaguda/tratamento farmacológico , Panencefalite Esclerosante Subaguda/etiologia , Panencefalite Esclerosante Subaguda/virologia , Proteínas Virais/análise , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
Neutralizing antibodies are considered a correlate of protection against severe human respiratory syncytial virus (HRSV) disease. Currently, HRSV neutralization assays are performed on immortalized cell lines like Vero or A549 cells. It is known that assays on these cell lines exclusively detect neutralizing antibodies (nAbs) directed to the fusion (F) protein. For the detection of nAbs directed to the glycoprotein (G), ciliated epithelial cells expressing the cellular receptor CX3CR1 are required, but generation of primary cell cultures is expensive and labor-intensive. Here, we developed a high-throughput neutralization assay based on the interaction between clinically relevant HRSV grown on primary cells with ciliated epithelial cells, and validated this assay using a panel of infant sera. To develop the high-throughput neutralization assay, we established a culture of differentiated apical-out airway organoids (Ap-O AO). CX3CR1 expression was confirmed, and both F- and G-specific monoclonal antibodies neutralized HRSV in the Ap-O AO. In a side-by-side neutralization assay on Vero cells and Ap-O AO, neutralizing antibody levels in sera from 125 infants correlated well, although titers on Ap-O AO were consistently lower. We speculate that these lower titers might be an actual reflection of the neutralizing antibody capacity in vivo. The organoid-based neutralization assay described here holds promise for further characterization of correlates of protection against HRSV disease.
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Anticorpos Neutralizantes , Receptor 1 de Quimiocina CX3C , Testes de Neutralização , Organoides , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Humanos , Vírus Sincicial Respiratório Humano/imunologia , Anticorpos Neutralizantes/imunologia , Organoides/metabolismo , Organoides/imunologia , Organoides/virologia , Organoides/citologia , Animais , Testes de Neutralização/métodos , Chlorocebus aethiops , Células Vero , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Receptor 1 de Quimiocina CX3C/metabolismo , Receptor 1 de Quimiocina CX3C/imunologia , Anticorpos Antivirais/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/metabolismo , Lactente , Células Epiteliais/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/virologia , Anticorpos Monoclonais/imunologiaRESUMO
BackgroundFollowing the 2022-2023 mpox outbreak, crucial knowledge gaps exist regarding orthopoxvirus-specific immunity in risk groups and its impact on future outbreaks.AimWe combined cross-sectional seroprevalence studies in two cities in the Netherlands with mathematical modelling to evaluate scenarios of future mpox outbreaks among men who have sex with men (MSM).MethodsSerum samples were obtained from 1,065 MSM attending Centres for Sexual Health (CSH) in Rotterdam or Amsterdam following the peak of the Dutch mpox outbreak and the introduction of vaccination. For MSM visiting the Rotterdam CSH, sera were linked to epidemiological and vaccination data. An in-house developed ELISA was used to detect vaccinia virus (VACV)-specific IgG. These observations were combined with published data on serial interval and vaccine effectiveness to inform a stochastic transmission model that estimates the risk of future mpox outbreaks.ResultsThe seroprevalence of VACV-specific antibodies was 45.4% and 47.1% in Rotterdam and Amsterdam, respectively. Transmission modelling showed that the impact of risk group vaccination on the original outbreak was likely small. However, assuming different scenarios, the number of mpox cases in a future outbreak would be markedly reduced because of vaccination. Simultaneously, the current level of immunity alone may not prevent future outbreaks. Maintaining a short time-to-diagnosis is a key component of any strategy to prevent new outbreaks.ConclusionOur findings indicate a reduced likelihood of large future mpox outbreaks among MSM in the Netherlands under current conditions, but emphasise the importance of maintaining population immunity, diagnostic capacities and disease awareness.
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Surtos de Doenças , Homossexualidade Masculina , Humanos , Masculino , Países Baixos/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , Homossexualidade Masculina/estatística & dados numéricos , Adulto , Pessoa de Meia-Idade , Vacínia/epidemiologia , Anticorpos Antivirais/sangue , Vacinação/estatística & dados numéricos , Adulto Jovem , Modelos Teóricos , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/sangueRESUMO
Purpose: Previous studies have demonstrated that the majority of patients with an inborn error of immunity (IEI) develop a spike (S)-specific IgG antibody and T-cell response after two doses of the mRNA-1273 COVID-19 vaccine, but little is known about the response to a booster vaccination. We studied the immune responses 8 weeks after booster vaccination with mRNA-based COVID-19 vaccines in 171 IEI patients. Moreover, we evaluated the clinical outcomes in these patients one year after the start of the Dutch COVID-19 vaccination campaign. Methods: This study was embedded in a large prospective multicenter study investigating the immunogenicity of COVID-19 mRNA-based vaccines in IEI (VACOPID study). Blood samples were taken from 244 participants 8 weeks after booster vaccination. These participants included 171 IEI patients (X-linked agammaglobulinemia (XLA;N=11), combined immunodeficiency (CID;N=4), common variable immunodeficiency (CVID;N=45), isolated or undefined antibody deficiencies (N=108) and phagocyte defects (N=3)) and 73 controls. SARS-CoV-2-specific IgG titers, neutralizing antibodies, and T-cell responses were evaluated. One year after the start of the COVID-19 vaccination program, 334 study participants (239 IEI patients and 95 controls) completed a questionnaire to supplement their clinical data focusing on SARS-CoV-2 infections. Results: After booster vaccination, S-specific IgG titers increased in all COVID-19 naive IEI cohorts and controls, when compared to titers at 6 months after the priming regimen. The fold-increases did not differ between controls and IEI cohorts. SARS-CoV-2-specific T-cell responses also increased equally in all cohorts after booster vaccination compared to 6 months after the priming regimen. Most SARS-CoV-2 infections during the study period occurred in the period when the Omicron variant had become dominant. The clinical course of these infections was mild, although IEI patients experienced more frequent fever and dyspnea compared to controls and their symptoms persisted longer. Conclusion: Our study demonstrates that mRNA-based booster vaccination induces robust recall of memory B-cell and T-cell responses in most IEI patients. One-year clinical follow-up demonstrated that SARS-CoV-2 infections in IEI patients were mild. Given our results, we support booster campaigns with newer variant-specific COVID-19 booster vaccines to IEI patients with milder phenotypes.
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Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , Masculino , Feminino , SARS-CoV-2/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Adulto , Pessoa de Meia-Idade , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Seguimentos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Estudos Prospectivos , Linfócitos T/imunologia , Adulto Jovem , Vacinação , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Síndromes de Imunodeficiência/imunologia , AdolescenteRESUMO
Healthy individuals with hybrid immunity, due to a SARS-CoV-2 infection prior to first vaccination, have stronger immune responses compared to those who were exclusively vaccinated. However, little is known about the characteristics of antibody, B- and T-cell responses in kidney disease patients with hybrid immunity. Here, we explored differences between kidney disease patients and controls with hybrid immunity after asymptomatic or mild coronavirus disease-2019 (COVID-19). We studied the kinetics, magnitude, breadth and phenotype of SARS-CoV-2-specific immune responses against primary mRNA-1273 vaccination in patients with chronic kidney disease or on dialysis, kidney transplant recipients, and controls with hybrid immunity. Although vaccination alone is less immunogenic in kidney disease patients, mRNA-1273 induced a robust immune response in patients with prior SARS-CoV-2 infection. In contrast, kidney disease patients with hybrid immunity develop SARS-CoV-2 antibody, B- and T-cell responses that are equally strong or stronger than controls. Phenotypic analysis showed that Spike (S)-specific B-cells varied between groups in lymph node-homing and memory phenotypes, yet S-specific T-cell responses were phenotypically consistent across groups. The heterogeneity amongst immune responses in hybrid immune kidney patients warrants further studies in larger cohorts to unravel markers of long-term protection that can be used for the design of targeted vaccine regimens.
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OBJECTIVE: We evaluated the immunogenicity of a bivalent BA.1 COVID-19 booster vaccine in people with HIV (PWH). DESIGN: Prospective observational cohort study. METHODS: PWH aged ≥45âyears received Wuhan-BA.1 mRNA-1273.214 and those <45âyears Wuhan-BA.1 BNT162b2. Participants were propensity score-matched 1â:â2 to people without HIV (non-PWH) by age, primary vaccine platform (mRNA-based or vector-based), number of prior COVID-19 boosters and SARS-CoV-2 infections, and spike (S1)-specific antibodies on the day of booster administration. The primary endpoint was the geometric mean ratio (GMR) of ancestral S1-specific antibodies from day 0 to 28 in PWH compared to non-PWH. Secondary endpoints included humoral responses, T-cell responses and cytokine responses up to 180âdays post-vaccination. RESULTS: Forty PWH received mRNA-1273.214 ( N â=â35) or BNT162b2 ( N â=â5) following mRNA-based ( N â=â29) or vector-based ( N â=â11) primary vaccination. PWH were predominantly male (87% vs. 26% of non-PWH) and median 57âyears [interquartile range (IQR) 53-59]. Their median CD4 + T-cell count was 775 (IQR 511-965) and the plasma HIV-RNA load was <50âcopies/ml in 39/40. The GMR of S1-specific antibodies by 28âdays post-vaccination was comparable between PWH [4.48, 95% confidence interval (CI) 3.24-6.19] and non-PWH (4.07, 95% CI 3.42-4.83). S1-specific antibody responses were comparable between PWH and non-PWH up to 180âdays, and T-cell responses up to 90âdays post-vaccination. Interferon-γ, interleukin (IL)-2, and IL-4 cytokine concentrations increased 28âdays post-vaccination in PWH. CONCLUSION: A bivalent BA.1 booster vaccine was immunogenic in well treated PWH, eliciting comparable humoral responses to non-PWH. However, T-cell responses waned faster after 90âdays in PWH compared to non-PWH.
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Anticorpos Antivirais , Vacina BNT162 , Vacinas contra COVID-19 , COVID-19 , Infecções por HIV , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Infecções por HIV/imunologia , COVID-19/prevenção & controle , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , Vacina BNT162/administração & dosagem , Países Baixos , Adulto , SARS-CoV-2/imunologia , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Vacina de mRNA-1273 contra 2019-nCoV/administração & dosagem , Citocinas/imunologia , IdosoRESUMO
Bivalent COVID-19 vaccines comprising ancestral Wuhan-Hu-1 (WH1) and the Omicron BA.1 or BA.5 subvariant elicit enhanced serum antibody responses to emerging Omicron subvariants. Here, we characterized the RBD-specific memory B cell (Bmem) response following a fourth dose with a BA.1 or BA.5 bivalent vaccine, in direct comparison with a WH1 monovalent fourth dose. Healthcare workers previously immunized with mRNA or adenoviral vector monovalent vaccines were sampled before and one month after a fourth dose with a monovalent or a BA.1 or BA.5 bivalent vaccine. Serum neutralizing antibodies (NAb) were quantified, as well as RBD-specific Bmem with an in-depth spectral flow cytometry panel including recombinant RBD proteins of the WH1, BA.1, BA.5, BQ.1.1, and XBB.1.5 variants. Both bivalent vaccines elicited higher NAb titers against Omicron subvariants compared to the monovalent vaccine. Following either vaccine type, recipients had slightly increased WH1 RBD-specific Bmem numbers. Both bivalent vaccines significantly increased WH1 RBD-specific Bmem binding of all Omicron subvariants tested by flow cytometry, while recognition of Omicron subvariants was not enhanced following monovalent vaccination. IgG1+ Bmem dominated the response, with substantial IgG4+ Bmem only detected in recipients of an mRNA vaccine for their primary dose. Thus, Omicron-based bivalent vaccines can significantly boost NAb and Bmem specific for ancestral WH1 and Omicron variants and improve recognition of descendent subvariants by pre-existing, WH1-specific Bmem beyond that of a monovalent vaccine. This provides new insights into the capacity of variant-based mRNA booster vaccines to improve immune memory against emerging SARS-CoV-2 variants and potentially protect against severe disease. ONE-SENTENCE SUMMARY: Omicron BA.1 and BA.5 bivalent COVID-19 boosters, used as a fourth dose, increase RBD-specific Bmem cross-recognition of Omicron subvariants, both those encoded by the vaccines and antigenically distinct subvariants, further than a monovalent booster.
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OBJECTIVES: The 2022 mpox epidemic reached a peak in Belgium and the rest of Europe in July 2022, after which it unexpectedly subsided. This study investigates epidemiological, behavioral, and immunological factors behind the waning of the epidemic in Belgium. METHODS: We investigated temporal evolutions in the characteristics and behavior of mpox patients using national surveillance data and data from a prospective registry of mpox patients in the Institute of Tropical Medicine (Antwerp). We studied behavioral changes in the population at risk using a survey among HIV-preexposure prophylaxis (PrEP) users. We determined the seroprevalence of anti-orthopoxvirus antibodies among HIV-PrEP users across four-time points in 2022. RESULTS: Mpox patients diagnosed at the end of the epidemic had less sexual risk behavior compared to those diagnosed earlier: they engaged less in sex at mass events, had fewer sexual partners, and were less likely to belong to the sexual network's central group. Among HIV-PrEP users there were no notable changes in sexual behavior. Anti-orthopoxvirus seroprevalence did not notably increase before the start of national vaccination campaigns. CONCLUSION: The observed changes in group immunity and behavior in the population at greater risk of exposure to mpox seem unable to explain the waning of the mpox epidemic. A change in the profile of mpox patients might have contributed to the decline in cases.
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Infecções por HIV , Comportamento Sexual , Humanos , Bélgica/epidemiologia , Estudos Soroepidemiológicos , Masculino , Adulto , Infecções por HIV/epidemiologia , Pessoa de Meia-Idade , Feminino , Profilaxia Pré-Exposição , Estudos Prospectivos , Assunção de Riscos , Anticorpos Antivirais/sangueRESUMO
BACKGROUND: Insight into cellular immune responses to COVID-19 vaccinations is crucial for optimizing booster programs in kidney transplant recipients (KTRs). METHODS: In an immunologic substudy of a multicenter randomized controlled trial (NCT05030974) investigating different repeated vaccination strategies in KTR who showed poor serological responses after 2 or 3 doses of an messenger RNA (mRNA)-based vaccine, we compared SARS-CoV-2-specific interleukin-21 memory T-cell and B-cell responses by enzyme-linked immunosorbent spot (ELISpot) assays and serum IgG antibody levels. Patients were randomized to receive: a single dose of mRNA-1273 (100 µg, nâ =â 25), a double dose of mRNA-1273 (2 × 100 µg, nâ =â 25), or a single dose of adenovirus type 26 encoding the SARS-CoV-2 spike glycoprotein (Ad26.COV2.S) (nâ =â 25). In parallel, we also examined responses in 50 KTR receiving 100 µg mRNA-1273, randomized to continue (nâ =â 25) or discontinue (nâ =â 25) mycophenolate mofetil/mycophenolic acid. As a reference, the data were compared with KTR who received 2 primary mRNA-1273 vaccinations. RESULTS: Repeated vaccination increased the seroconversion rate from 21% to 66% in all patients, which was strongly associated with enhanced levels of SARS-CoV-2-specific interleukin-21 memory T cells (odd ratio, 3.84 [1.89-7.78]; Pâ <â 0.001) and B cells (odd ratio, 35.93 [6.94-186.04]; Pâ <â 0.001). There were no significant differences observed in these responses among various vaccination strategies. In contrast to KTR vaccinated with 2 primary vaccinations, the number of antigen-specific memory B cells demonstrated potential for classifying seroconversion after repeated vaccination (area under the curve, 0.64; 95% confidence interval, 0.37-0.90; Pâ =â 0.26 and area under the curve, 0.95; confidence interval, 0.87-0.97; Pâ <â 0.0001, respectively). CONCLUSIONS: Our study emphasizes the importance of virus-specific memory T- and B-cell responses for comprehensive understanding of COVID-19 vaccine efficacy among KTR.
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Waning antibody responses after COVID-19 vaccination combined with the emergence of the SARS-CoV-2 Omicron lineage led to reduced vaccine effectiveness. As a countermeasure, bivalent mRNA-based booster vaccines encoding the ancestral spike protein in combination with that of Omicron BA.1 or BA.5 were introduced. Since then, different BA.2-descendent lineages have become dominant, such as XBB.1.5, JN.1, or EG.5.1. Here, we report post-hoc analyses of data from the SWITCH-ON study, assessing how different COVID-19 priming regimens affect the immunogenicity of bivalent booster vaccinations and breakthrough infections (NCT05471440). BA.1 and BA.5 bivalent vaccines boosted neutralizing antibodies and T-cells up to 3 months after boost; however, cross-neutralization of XBB.1.5 was poor. Interestingly, different combinations of prime-boost regimens induced divergent responses: participants primed with Ad26.COV2.S developed lower binding antibody levels after bivalent boost while neutralization and T-cell responses were similar to mRNA-based primed participants. In contrast, the breadth of neutralization was higher in mRNA-primed and bivalent BA.5 boosted participants. Combined, our data further support the current use of monovalent vaccines based on circulating strains when vaccinating risk groups, as recently recommended by the WHO. We emphasize the importance of the continuous assessment of immune responses targeting circulating variants to guide future COVID-19 vaccination policies.
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Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Linfócitos T/imunologia , VacinaçãoRESUMO
Background: Data on cellular response and the decay of antibodies and T cells in time are scarce in lung transplant recipients (LTRs). Additionally, the development and durability of humoral and cellular immune responses have not been investigated in patients on the waitlist for lung transplantation (WLs). Here, we report our 6-month follow-up of humoral and cellular immune responses of LTRs and WLs, compared with controls. Methods: Humoral responses to two doses of the mRNA-1273 vaccination were assessed by determining spike (S)-specific IgG antibodies and neutralizing antibodies. Cellular responses were investigated by interferon gamma (IFN-γ) release assay (IGRA) and IFN-γ ELISpot assay at 28 days and 6 months after the second vaccination. Results: In LTRs, the level of antibodies and T-cell responses was significantly lower at 28 days after the second vaccination. Also, WLs had lower antibody titers and lower T-cell responses compared with controls. Six months after the second vaccination, all groups showed a decrease in antibody titers and T-cell responses. In WLs, the rate of decline of neutralizing antibodies and T-cell responses was significantly higher than in controls. Conclusion: Our results show that humoral and cellular responses in LTRs, if they develop, decrease at rates comparable with controls. In contrast, the inferior cellular responses and the rapid decay of both humoral and cellular responses in the WL groups imply that WLs may not be protected adequately by two vaccinations and repeat boostering may be necessary to induce protection that lasts beyond the months immediately post-transplantation.