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1.
J Virol ; 98(4): e0119023, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38501840

RESUMO

Topically applied microbicides may play a critical role in preventing sexual transmission of human immunodeficiency virus type 1 (HIV-1); however, their efficacy can be compromised by amyloid fibrils present in semen, which significantly increase HIV-1 infectivity. This phenomenon may have contributed to the failure of most microbicide candidates in clinical settings. Understanding the impact of semen on microbicide effectiveness is thus crucial. In our study, we evaluated the influence of semen on the neutralizing activity of broadly neutralizing antibodies (bNAbs), including PG16, PGT121, 10-1074, 3BNC117, and VRC01, which are potential microbicide candidates. We found that semen enhances infection of HIV-1 transmitted/founder viruses but only marginally affects the neutralizing activity of tested antibodies, suggesting their potential for microbicide application. Our findings underscore the need to consider semen-mediated enhancement when evaluating and developing microbicides and highlight the potential of incorporating HIV-1 bNAbs in formulations to enhance efficacy and mitigate HIV-1 transmission during sexual encounters.IMPORTANCEThis study examined the impact of semen on the development of microbicides, substances used to prevent the transmission of HIV-1 during sexual activity. Semen contains certain components that can render the virus more infectious, posing a challenge to microbicide effectiveness. Researchers specifically investigated the effect of semen on a group of powerful antibodies called broadly neutralizing antibodies, which can neutralize a large spectrum of different HIV-1 variants. The results revealed that semen only had a minimal effect on the antibodies' ability to neutralize the virus. This is promising because it suggests that these antibodies could still be effective in microbicides, even in the presence of semen. Understanding this interaction is crucial for developing better strategies to prevent HIV-1 transmission. By incorporating the knowledge gained from this study, scientists can now focus on creating microbicides that consider the impact of semen, bringing us closer to more effective prevention methods.


Assuntos
Anti-Infecciosos , Infecções por HIV , HIV-1 , Sêmen , Humanos , Anti-Infecciosos/farmacologia , Anticorpos Neutralizantes , Antivirais/farmacologia , Anticorpos Amplamente Neutralizantes/farmacologia , Anticorpos Anti-HIV , Infecções por HIV/transmissão , HIV-1/fisiologia , Sêmen/química , Sêmen/virologia
2.
Infection ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492196

RESUMO

PURPOSE: The risk of developing active tuberculosis (TB) is considerably increased in people living with HIV/AIDS (PLWH). However, incidence of HIV/TB coinfection is difficult to assess as surveillance data are lacking in many countries. Here, we aimed to perform a quantitative analysis of HIV/TB coinfections within the Cologne/Bonn HIV cohort and to determine risk factors for active TB. METHODS: We systematically evaluated data of patients with HIV/TB coinfection between 2006 and 2017. In this retrospective analysis, we compared HIV/TB-coinfected patients with a cohort of HIV-positive patients. The incidence density rate (IDR) was calculated for active TB cases at different time points. RESULTS: During 2006-2017, 60 out of 4673 PLWH were diagnosed with active TB. Overall IDR was 0.181 cases/100 patient-years and ranged from 0.266 in 2006-2009 to 0.133 in 2014-2017. Patients originating from Sub-Saharan Africa had a significantly (p < 0.001) higher IDR (0.694/100 patient-years of observation, 95% CI [0.435-1.050]) in comparison to patients of German origin (0.053/100 patient-years of observation, 95% CI [0.028-0.091]). In terms of TB-free survival, individuals originating from countries with a TB incidence higher than 10/100,000 exhibited a markedly reduced TB-free survival compared to those originating from regions with lower incidence (p < 0.001). In 22 patients, TB and HIV infection were diagnosed simultaneously. CONCLUSION: Overall, we observed a decline in the incidence density rate (IDR) of HIV/TB coinfections between 2006 and 2017. Patients originating from regions with high incidence bear a higher risk of falling ill with active TB. For PLWH born in Germany, the observed risk of active TB appears to be lower compared to other groups within the cohort. These findings should be considered when developing TB containment and screening strategies for PLWH in low-incidence countries.

3.
Blood Adv ; 8(4): 968-977, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38207206

RESUMO

ABSTRACT: Large B-cell lymphoma (LBCL) carrying MYC rearrangement, alone or together with BCL2 and/or BCL6 translocations, have shown a poor prognosis when treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in the HIV population. Scanty data are available on the prevalence and prognostic impact of MYC rearrangements in HIV-associated LBCL. We conducted a retrospective study to evaluate the clinical effect of MYC rearrangement in HIV-associated LBCL. We evaluated clinical characteristics, treatment received, and outcome of LBCL in patients with HIV with MYC rearrangement (MYC+) and without MYC rearrangement (MYC-). A total of 155 patients with HIV who had received fluorescence in situ hybridization analysis for MYC were enrolled in 11 European centers: 43 with MYC+ and 112 MYC-. Among patients with MYC, 10 had double-/triple-hit lymphomas, and 33 had isolated MYC rearrangement (single-hit lymphoma). Patients with MYC+ had more frequently advanced stage, >2 extranodal site at presentation, and higher proliferative index. There were no significant differences in overall survival and progression-free survival (PFS) between the 2 groups. However, patients with MYC+ received more frequently intensive chemotherapy (iCT) (44%) than (R)CHOP alone (35%) or infusional treatment (DA-EPOCH-R and R-CDE) (19%). Among patients with MYC+, those who received iCT achieved a better outcome than patients who received nonintensive treatment (complete remission, 84% vs 52%; P = .028; 5-year PFS, 66% vs 36%; P = .021). Our retrospective results suggest that HIV-associated LBCL with MYC+ could be considered for an intensive therapeutic approach whenever possible, whereas (R)CHOP seems to give inferior results in this subset of patients in terms of complete remission and PFS.


Assuntos
Infecções por HIV , Linfoma Difuso de Grandes Células B , Humanos , Ciclofosfamida/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hibridização in Situ Fluorescente , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/genética , Estudos Retrospectivos , Rituximab/uso terapêutico , Vincristina/uso terapêutico
4.
Nat Commun ; 14(1): 7137, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932288

RESUMO

HIV-1 broadly neutralizing antibodies (bNAbs) are able to suppress viremia and prevent infection. Their induction by vaccination is therefore a major goal. However, in contrast to antibodies that neutralize other pathogens, HIV-1-specific bNAbs frequently carry uncommon molecular characteristics that might prevent their induction. Here, we perform unbiased sequence analyses of B cell receptor repertoires from 57 uninfected and 46 chronically HIV-1- or HCV-infected individuals and learn probabilistic models to predict the likelihood of bNAb development. We formally show that lower probabilities for bNAbs are predictive of higher HIV-1 neutralization activity. Moreover, ranking bNAbs by their probabilities allows to identify highly potent antibodies with superior generation probabilities as preferential targets for vaccination approaches. Importantly, we find equal bNAb probabilities across infected and uninfected individuals. This implies that chronic infection is not a prerequisite for the generation of bNAbs, fostering the hope that HIV-1 vaccines can induce bNAb development in uninfected people.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-HIV , Anticorpos Neutralizantes
5.
Nat Med ; 29(11): 2763-2774, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37957379

RESUMO

Human immunodeficiency virus type 1 (HIV-1)-neutralizing antibodies (nAbs) that prevent infection are the main goal of HIV vaccine discovery. But as no nAb-eliciting vaccines are yet available, only data from HIV-1 neutralizers-persons with HIV-1 who naturally develop broad and potent nAbs-can inform about the dynamics and durability of nAb responses in humans, knowledge which is crucial for the design of future HIV-1 vaccine regimens. To address this, we assessed HIV-1-neutralizing immunoglobulin G (IgG) from 2,354 persons with HIV-1 on or off antiretroviral therapy (ART). Infection with non-clade B viruses, CD4+ T cell counts <200 µl-1, being off ART and a longer time off ART were independent predictors of a more potent and broad neutralization. In longitudinal analyses, we found nAb half-lives of 9.3 and 16.9 years in individuals with no- or low-level viremia, respectively, and 4.0 years in persons who newly initiated ART. Finally, in a potent HIV-1 neutralizer, we identified lower fractions of serum nAbs and of nAb-encoding memory B cells after ART initiation, suggesting that a decreasing neutralizing serum activity after antigen withdrawal is due to lower levels of nAbs. These results collectively show that HIV-1-neutralizing responses can persist for several years, even at low antigen levels, suggesting that an HIV-1 vaccine may elicit a durable nAb response.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , HIV-1 , Humanos , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Replicação Viral
6.
Front Immunol ; 14: 1226622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781408

RESUMO

Background: While the short-term symptoms of post-COVID syndromes (PCS) are well-known, the long-term clinical characteristics, risk factors and outcomes of PCS remain unclear. Moreover, there is ongoing discussion about the effectiveness of post-infection vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) to aid in PCS recovery. Methods: In this longitudinal and observational case-control study we aimed at identifying long-term PCS courses and evaluating the effects of post-infection vaccinations on PCS recovery. Individuals with initial mild COVID-19 were followed for a period of 15 months after primary infection. We assessed PCS outcomes, distinct symptom clusters (SC), and SARS-CoV-2 immunoglobulin G (IgG) levels in patients who received SARS-CoV-2 vaccination, as well as those who did not. To identify potential associating factors with PCS, we used binomial regression models and reported the results as odds ratios (OR) with 95% confidence intervals (95%CI). Results: Out of 958 patients, follow-up data at 15 month after infection was obtained for 222 (23.2%) outpatients. Of those individuals, 36.5% (81/222) and 31.1% (69/222) were identified to have PCS at month 10 and 15, respectively. Fatigue and dyspnea (SC2) rather than anosmia and ageusia (SC1) constituted PCS at month 15. SARS-CoV-2 IgG levels were equally distributed over time among age groups, sex, and absence/presence of PCS. Of the 222 patients, 77.0% (171/222) were vaccinated between 10- and 15-months post-infection, but vaccination did not affect PCS recovery at month 15. 26.3% of unvaccinated and 25.8% of vaccinated outpatients improved from PCS (p= .9646). Baseline headache (SC4) and diarrhoea (SC5) were risk factors for PCS at months 10 and 15 (SC4: OR 1.85 (95%CI 1.04-3.26), p=.0390; SC5: OR 3.27(95%CI 1.54-6.64), p=.0009). Conclusion: Based on the specific symptoms of PCS our findings show a shift in the pattern of recovery. We found no effect of SARS-CoV-2 vaccination on PCS recovery and recommend further studies to identify predicting biomarkers and targeted PCS therapeutics.


Assuntos
COVID-19 , Pacientes Ambulatoriais , Síndrome de COVID-19 Pós-Aguda , Humanos , Estudos de Casos e Controles , Vacinas contra COVID-19/administração & dosagem , Imunoglobulina G , Fatores de Risco , SARS-CoV-2 , Vacinação , Estudos Longitudinais
8.
Cell Host Microbe ; 31(7): 1200-1215.e9, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37327779

RESUMO

Understanding the specificities of human serum antibodies that broadly neutralize HIV can inform prevention and treatment strategies. Here, we describe a deep mutational scanning system that can measure the effects of combinations of mutations to HIV envelope (Env) on neutralization by antibodies and polyclonal serum. We first show that this system can accurately map how all functionally tolerated mutations to Env affect neutralization by monoclonal antibodies. We then comprehensively map Env mutations that affect neutralization by a set of human polyclonal sera that neutralize diverse strains of HIV and target the site engaging the host receptor CD4. The neutralizing activities of these sera target different epitopes, with most sera having specificities reminiscent of individual characterized monoclonal antibodies, but one serum targeting two epitopes within the CD4-binding site. Mapping the specificity of the neutralizing activity in polyclonal human serum will aid in assessing anti-HIV immune responses to inform prevention strategies.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Mutação , Epitopos/genética , HIV-1/genética , Anticorpos Monoclonais , Proteína gp120 do Envelope de HIV/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
9.
Front Med (Lausanne) ; 10: 1129288, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168268

RESUMO

Background: Symptoms lasting longer than 12 weeks after severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection are called post-coronavirus disease (COVID) syndrome (PCS). The identification of new biomarkers that predict the occurrence or course of PCS in terms of a post-viral syndrome is vital. T-cell dysfunction, cytokine imbalance, and impaired autoimmunity have been reported in PCS. Nevertheless, there is still a lack of conclusive information on the underlying mechanisms due to, among other things, a lack of controlled study designs. Methods: Here, we conducted a prospective, controlled study to characterize the humoral and cellular immune response in unvaccinated patients with and without PCS following SARS-CoV-2 infection over 7 months and unexposed donors. Results: Patients with PCS showed as early as 6 weeks and 7 months after symptom onset significantly increased frequencies of SARS-CoV-2-specific CD4+ and CD8+ T-cells secreting IFNγ, TNF, and expressing CD40L, as well as plasmacytoid dendritic cells (pDC) with an activated phenotype. Remarkably, the immunosuppressive counterparts type 1 regulatory T-cells (TR1: CD49b/LAG-3+) and IL-4 were more abundant in PCS+. Conclusion: This work describes immunological alterations between inflammation and immunosuppression in COVID-19 convalescents with and without PCS, which may provide potential directions for future epidemiological investigations and targeted treatments.

10.
HIV Med ; 24(7): 785-793, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36883641

RESUMO

OBJECTIVES: Our objective was to assess immune responses and their influencing factors in people living with HIV after messenger RNA (mRNA)-based COVID-19 booster vaccination (third dose). METHODS: This was a retrospective cohort study of people living with HIV who received booster vaccination with BNT-162b2 or mRNA-1273 between October 2021 and January 2022. We assessed anti-spike receptor-binding domain (RBD) immunoglobulin G (IgG), virus neutralizing activity (VNA) titres reported as 100% inhibitory dilution (ID100 ), and T-cell response (using interferon-gamma-release-assay [IGRA]) at baseline and quarterly follow-up visits. Patients with reported COVID-19 during follow-up were excluded. Predictors of serological immune response were analyzed using multivariate regression models. RESULTS: Of 84 people living with HIV who received an mRNA-based booster vaccination, 76 were eligible for analysis. Participants were on effective antiretroviral therapy (ART) and had a median of 670 CD4+ cells/µL (interquartile range [IQR] 540-850). Following booster vaccination, median anti-spike RBD IgG increased by 705.2 binding antibody units per millilitre (BAU/mL) and median VNA titres increased by 1000 ID100 at the follow-up assessment (median 13 weeks later). Multivariate regression revealed that time since second vaccination was a predictor of stronger serological responses (p < 0.0001). No association was found for other factors, including CD4+ status, choice of mRNA vaccine, or concomitant influenza vaccination. In total, 45 patients (59%) had a reactive baseline IGRA, of whom two lost reactivity during follow-up. Of 31 patients (41%) with non-reactive baseline IGRA, 17 (55%) converted to reactive and seven (23%) remained unchanged following booster vaccination. CONCLUSIONS: People living with HIV with ≥500 CD4+ cells/µL showed favourable immune responses to mRNA-based COVID-19 booster vaccination. A longer time (up to 29 weeks) since second vaccination was associated with higher serological responses, whereas choice of mRNA vaccine or concomitant influenza vaccination had no impact.


Assuntos
COVID-19 , Infecções por HIV , Influenza Humana , Humanos , Estudos Retrospectivos , COVID-19/prevenção & controle , Vacinação , RNA Mensageiro , Imunidade , Imunoglobulina G , Anticorpos Antivirais
11.
bioRxiv ; 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36993197

RESUMO

Understanding the specificities of human serum antibodies that broadly neutralize HIV can inform prevention and treatment strategies. Here we describe a deep mutational scanning system that can measure the effects of combinations of mutations to HIV envelope (Env) on neutralization by antibodies and polyclonal serum. We first show that this system can accurately map how all functionally tolerated mutations to Env affect neutralization by monoclonal antibodies. We then comprehensively map Env mutations that affect neutralization by a set of human polyclonal sera known to target the CD4-binding site that neutralize diverse strains of HIV. The neutralizing activities of these sera target different epitopes, with most sera having specificities reminiscent of individual characterized monoclonal antibodies, but one sera targeting two epitopes within the CD4 binding site. Mapping the specificity of the neutralizing activity in polyclonal human serum will aid in assessing anti-HIV immune responses to inform prevention strategies.

12.
Cell Host Microbe ; 30(9): 1231-1241.e6, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35921836

RESUMO

SARS-CoV-2 neutralizing antibodies play a critical role in COVID-19 prevention and treatment but are challenged by viral evolution and the emergence of novel escape variants. Importantly, the recently identified Omicron sublineages BA.2.12.1 and BA.4/5 are rapidly becoming predominant in various countries. By determining polyclonal serum activity of 50 convalescent or vaccinated individuals against BA.1, BA.1.1, BA.2, BA.2.12.1, and BA.4/5, we reveal a further reduction in BA.4/5 susceptibility to vaccinee sera. Most notably, delineation of sensitivity to an extended 163-antibody panel demonstrates pronounced antigenic differences with distinct escape patterns among Omicron sublineages. Antigenic distance and/or higher resistance may therefore favor immune-escape-mediated BA.4/5 expansion after the first Omicron wave. Finally, while most clinical-stage monoclonal antibodies are inactive against Omicron sublineages, we identify promising antibodies with high pan-SARS-CoV-2 neutralizing potency. Our study provides a detailed understanding of Omicron-sublineage antibody escape that can inform on effective strategies against COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Testes de Neutralização , Glicoproteína da Espícula de Coronavírus/genética
13.
Sci Adv ; 8(32): eabp8155, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35960796

RESUMO

The induction of broadly neutralizing antibodies (bNAbs) is a potential strategy for a vaccine against HIV-1. However, most bNAbs exhibit features such as unusually high somatic hypermutation, including insertions and deletions, which make their induction challenging. VRC01-class bNAbs not only exhibit extraordinary breadth and potency but also rank among the most highly somatically mutated bNAbs. Here, we describe a VRC01-class antibody isolated from a viremic controller, BG24, that is much less mutated than most relatives of its class while achieving comparable breadth and potency. A 3.8-Å x-ray crystal structure of a BG24-BG505 Env trimer complex revealed conserved contacts at the gp120 interface characteristic of the VRC01-class Abs, despite lacking common CDR3 sequence motifs. The existence of moderately mutated CD4-binding site (CD4bs) bNAbs such as BG24 provides a simpler blueprint for CD4bs antibody induction by a vaccine, raising the prospect that such an induction might be feasible with a germline-targeting approach.

14.
AIDS ; 36(15): 2107-2119, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35848573

RESUMO

BACKGROUND: Weight gain is becoming increasingly prevalent amongst people with HIV (PWH) receiving contemporary antiretroviral treatment. We investigated BMI changes and clinical impact in a large prospective observational study. METHODS: PWH aged ≥18 years were included who started a new antiretroviral (baseline) during 2010-2019 with baseline and ≥1 follow-up BMI assessment available. Rates of clinical outcomes (cardiovascular disease [CVD], malignancies, diabetes mellitus [DM] and all-cause mortality) were analysed using Poisson regression to assess effect of time-updated BMI changes (>1 kg/m 2 decrease, ±1 kg/m 2 stable, >1 kg/m 2 increase), lagged by 1-year to reduce reverse causality. Analyses were adjusted for baseline BMI plus key confounders including antiretroviral exposure. RESULTS: 6721 PWH were included; 72.3% were male, median age 48 years (interquartile range [IQR] 40-55). At baseline, 8.4% were antiretroviral-naive, and 5.0% were underweight, 59.7% healthy weight, 27.5% overweight, and 7.8% were living with obesity. There was an 8.2% increase in proportion of overweight and 4.8% in obesity over the study period (median follow-up 4.4 years [IQR 2.6-6.7]).100 CVDs, 149 malignancies, 144 DMs, and 257 deaths were observed with incidence rates 4.4, 6.8, 6.6, 10.6 per 1000 person-years of follow-up, respectively. Compared to stable BMI, >1 kg/m 2 increase was associated with increased risk of DM (adjusted incidence rate ratio [IRR]: 1.96, 95% confidence interval [CI]: 1.36-2.80) and >1 kg/m 2 decrease with increased risk of death (adjusted IRR: 2.33, 95% CI: 1.73-3.13). No significant associations were observed between BMI changes and CVD or malignancies. CONCLUSIONS: A BMI increase was associated with DM and a decrease associated with death.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Infecções por HIV , Neoplasias , Masculino , Humanos , Adolescente , Adulto , Pessoa de Meia-Idade , Feminino , Índice de Massa Corporal , Sobrepeso/complicações , Sobrepeso/tratamento farmacológico , Sobrepeso/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Antirretrovirais/uso terapêutico , Obesidade/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Doenças Cardiovasculares/complicações , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Neoplasias/complicações , Fatores de Risco
15.
PLoS One ; 17(5): e0268530, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35613127

RESUMO

BACKGROUND: COVID-19 has so far affected more than 250 million individuals worldwide, causing more than 5 million deaths. Several risk factors for severe disease have been identified, most of which coincide with advanced age. In younger individuals, severe COVID-19 often occurs in the absence of obvious comorbidities. Guided by the finding of cytomegalovirus (CMV)-specific T cells with some cross-reactivity to SARS-CoV-2 in a COVID-19 intensive care unit (ICU) patient, we decided to investigate whether CMV seropositivity is associated with severe or critical COVID-19. Herpes simplex virus (HSV) serostatus was investigated as control. METHODS: National German COVID-19 bio-sample and data banks were used to retrospectively analyze the CMV and HSV serostatus of patients who experienced mild (n = 101), moderate (n = 130) or severe to critical (n = 80) disease by IgG serology. We then investigated the relationship between disease severity and herpesvirus serostatus via statistical models. RESULTS: Non-geriatric patients (< 60 years) with severe COVID-19 were found to have a very high prevalence of CMV-seropositivity, while CMV status distribution in individuals with mild disease was similar to the prevalence in the German population; interestingly, this was not detectable in older patients. Prediction models support the hypothesis that the CMV serostatus, unlike HSV, might be a strong biomarker in identifying younger individuals with a higher risk of developing severe COVID-19, in particular in absence of other co-morbidities. CONCLUSIONS: We identified 'CMV-seropositivity' as a potential novel risk factor for severe COVID-19 in non-geriatric individuals in the studied cohorts. More mechanistic analyses as well as confirmation of similar findings in cohorts representing the currently most relevant SARS-CoV-2 variants should be performed shortly.


Assuntos
COVID-19 , Infecções por Citomegalovirus , Herpes Simples , Idoso , Anticorpos Antivirais , COVID-19/epidemiologia , Citomegalovirus , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Humanos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
16.
Curr Opin Virol ; 54: 101211, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35306354

RESUMO

Potent broadly neutralizing antibodies (bNAbs) targeting HIV-1 exhibit significant antiviral activity in humans. Recent advances have demonstrated that novel antibodies and bNAb combinations can effectively restrict the development of viral escape mutations. Moreover, passive immunization trials have provided proof-of-principle for bNAb-mediated prevention of infection with antibody-sensitive HIV-1 strains. In contrast, clinical studies investigating the activity of HIV-1 bNAbs on the latent reservoir failed to demonstrate substantial effects. Clinical adoption of HIV-1 bNAbs will require the development of more potent and broadly active antibodies as well as their implementation in optimized strategies to fully harness the capabilities of bNAbs. We review preclinical and clinical studies on HIV-1 bNAbs to highlight their potential and remaining limitations.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Anticorpos Anti-HIV , Infecções por HIV/prevenção & controle , Humanos
17.
Emerg Infect Dis ; 28(5): 1050-1052, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35259088

RESUMO

To determine neutralizing activity against the severe acute respiratory syndrome coronavirus 2 ancestral strain and 4 variants of concern, we tested serum from 30 persons with breakthrough infection after 2-dose vaccination. Cross-variant neutralizing activity was comparable to that after 3-dose vaccination. Shorter intervals between vaccination and breakthrough infection correlated with lower neutralizing titers.


Assuntos
COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , SARS-CoV-2 , Vacinação
18.
Nat Med ; 28(3): 477-480, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35046572

RESUMO

The Omicron variant of SARS-CoV-2 is causing a rapid increase in infections across the globe. This new variant of concern carries an unusually high number of mutations in key epitopes of neutralizing antibodies on the viral spike glycoprotein, suggesting potential immune evasion. Here we assessed serum neutralizing capacity in longitudinal cohorts of vaccinated and convalescent individuals, as well as monoclonal antibody activity against Omicron using pseudovirus neutralization assays. We report a near-complete lack of neutralizing activity against Omicron in polyclonal sera from individuals vaccinated with two doses of the BNT162b2 COVID-19 vaccine and from convalescent individuals, as well as resistance to different monoclonal antibodies in clinical use. However, mRNA booster immunizations in vaccinated and convalescent individuals resulted in a significant increase of serum neutralizing activity against Omicron. This study demonstrates that booster immunizations can critically improve the humoral immune response against the Omicron variant.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunização Secundária , RNA Mensageiro , SARS-CoV-2/genética
19.
Cell Host Microbe ; 30(1): 69-82.e10, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34973165

RESUMO

A fraction of COVID-19 convalescent individuals mount a potent antibody response to SARS-CoV-2 with cross-reactivity to SARS-CoV-1. To uncover their humoral response in detail, we performed single B cell analysis from 10 SARS-CoV-2 elite neutralizers. We isolated and analyzed 126 monoclonal antibodies, many of which were sarbecovirus cross-reactive, with some displaying merbecovirus- and embecovirus-reactivity. Several isolated broadly neutralizing antibodies were effective against B.1.1.7, B.1.351, B.1.429, B.1.617, and B.1.617.2 variants and 19 prominent potential escape sites. Furthermore, assembly of 716,806 SARS-CoV-2 sequences predicted emerging escape variants, which were also effectively neutralized. One of these broadly neutralizing potent antibodies, R40-1G8, is a IGHV3-53 RBD-class-1 antibody. Remarkably, cryo-EM analysis revealed that R40-1G8 has a flexible binding mode, targeting both "up" and "down" conformations of the RBD. Given the threat of emerging SARS-CoV-2 variants, we demonstrate that elite neutralizers are a valuable source for isolating ultrapotent antibody candidates to prevent and treat SARS-CoV-2 infection.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/imunologia , COVID-19/virologia , Células Cultivadas , Chlorocebus aethiops , Reações Cruzadas/imunologia , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
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