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1.
Virol J ; 21(1): 68, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509536

RESUMO

PURPOSE: Besides the well-established efficacy in preventing severe COVID-19, the impact of early treatments, namely antivirals and monoclonal antibodies (mAbs), on the time length to negativization of SARS-CoV-2 nasal swabs is still unclear. The aim of this study was to compare the efficacy of different early treatments in reducing the SARS-CoV-2 viral shedding, identifying a single drug that might potentially lead to a more rapid negativization of SARS-CoV-2 nasal swab. METHODS: This was a single-centre, retrospective, observational study conducted at Ospedale Luigi Sacco in Milan. Data of high-risk COVID-19 patients who received early treatments between 23 December 2021 and March 2023 were extracted. The comparison across treatments was conducted using the Kruskall-Wallis test for continuous variables. Dunn's test with Bonferroni adjustment was performed for post-hoc comparisons of days to negativization. Secondly, a negative binomial regression adjusted for age, sex, number of comorbidities, immunosuppression, and SARS-CoV-2 vaccination status was implemented. RESULTS: Data from 428 patients receiving early treatments were collected. The majority were treated with Nirmatrelvir/Ritonavir and were affected by SARS-CoV-2 Omicron infection with BA.2 sublineage. The median length time to SARS-CoV-2 nasal swab negativization was 9 days [IQR 7-13 days]. We found that Nirmatrelvir/Ritonavir determined a significant decrease of the length time to SARS-CoV-2 nasal swab negativization compared to mAbs (p = 0.003), but not compared to Remdesivir (p = 0.147) and Molnupiravir (p = 0.156). CONCLUSION: Our findings highlight the importance of promptly treating high-risk COVID-19 patients with Nirmatrelvir/Ritonavir, as it also contributes to achieving a faster time to negative SARS-CoV-2 nasal swabs.


Assuntos
COVID-19 , Lactamas , Leucina , Nitrilas , Prolina , SARS-CoV-2 , Humanos , Anticorpos Monoclonais/uso terapêutico , Ritonavir/uso terapêutico , Vacinas contra COVID-19 , Estudos Retrospectivos , Tratamento Farmacológico da COVID-19 , Antivirais/uso terapêutico
2.
Int J Cancer ; 154(8): 1371-1376, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100252

RESUMO

Solid cancer patients are at higher risk of SARS-CoV-2 infection and severe complications. Moreover, vaccine-induced antibody response is impaired in patients on anticancer treatment. In this retrospective, observational, hypothesis-generating, cohort study, we assessed the antibody response to the third dose of mRNA vaccine in a convenience sample of patients on anticancer treatment, comparing it to that of the primary two-dose cycle. Among 99 patients included, 62.6% were ≥60 years old, 32.3% males, 67.7% with advanced disease. Exactly 40.4% were receiving biological therapy, 16.2% chemotherapy only and 7.1% both treatments. After the third dose, seroconversion rate seems to increase significantly, especially in non-responders to two doses. Heterologous vaccine-type regimen (two-dose mRNA-1273 and subsequent tozinameran or vice versa) results in higher antibody levels. This explorative study suggests that repeated doses of mRNA-vaccines could be associated with a better antibody response in this population. Furthermore, heterologous vaccine-type three-dose vaccination seems more effective in this population. Since this is a hypothesis-generating study, adequately statistically powered studies should validate these results.


Assuntos
COVID-19 , Neoplasias , Vacinas , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Formação de Anticorpos , Estudos de Coortes , Estudos Retrospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Neoplasias/tratamento farmacológico , RNA Mensageiro/genética , Anticorpos Antivirais
4.
Cancer Med ; 12(12): 12967-12974, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37114577

RESUMO

INTRODUCTION: Cancer patients are frail individuals, thus the prevention of SARS-CoV-2 infection is essential. To date, vaccination is the most effective tool to prevent COVID-19. In a previous study, we evaluated the immunogenicity of two doses of mRNA-based vaccines (BNT162b2 or mRNA-1273) in solid cancer patients. We found that seroconversion rate in cancer patients without a previous exposure to SARS-CoV-2 was lower than in healthy controls (66.7% vs. 95%, p = 0.0020). The present study aimed to evaluate the clinical efficacy of the vaccination in the same population. METHODS: This is a single-institution, prospective observational study. Data were collected through a predefined questionnaire through phone call in the period between the second and third vaccine dose. The primary objective was to describe the clinical efficacy of the vaccination, defined as the percentage of vaccinated subjects who did not develop symptomatic COVID-19 within 6 months after the second dose. The secondary objective was to describe the clinical features of patients who developed COVID-19. RESULTS: From January to June 2021, 195 cancer patients were enrolled. Considering that 7 (3.59%) patients tested positive for SARS-CoV-2 and 5 developed symptomatic disease, the clinical efficacy of the vaccination was 97.4%. COVID-19 disease in most patients was mild and managed at home; only one hospitalization was recorded and no patient required hospitalization in the intensive care unit. DISCUSSION: Our study suggests that increasing vaccination coverage, including booster doses, could improve the prevention of infection, hospitalization, serious illness, and death in the frail population of cancer patients.


Assuntos
COVID-19 , Neoplasias , Humanos , COVID-19/prevenção & controle , Vacina BNT162 , SARS-CoV-2 , Resultado do Tratamento , Neoplasias/terapia
5.
Int J Cancer ; 152(4): 661-671, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36056571

RESUMO

Previous studies on the immunogenicity of SARS-CoV-2 mRNA vaccines showed a reduced seroconversion in cancer patients. The aim of our study is to evaluate the immunogenicity of two doses of mRNA vaccines in solid cancer patients with or without a previous exposure to the virus. This is a single-institution, prospective, nonrandomized study. Patients in active treatment and a control cohort of healthy people received two doses of BNT162b2 (Comirnaty, BioNTech/Pfizer, The United States) or mRNA-1273 (Spikevax, Moderna). Vaccine was administered before starting anticancer therapy or on the first day of the treatment cycle. SARS-CoV-2 antibody levels against S1, RBD (to evaluate vaccine response) and N proteins (to evaluate previous infection) were measured in plasma before the first dose and 30 days after the second one. From January to June 2021, 195 consecutive cancer patients and 20 healthy controls were enrolled. Thirty-one cancer patients had a previous exposure to SARS-CoV-2. Cancer patients previously exposed to the virus had significantly higher median levels of anti-S1 and anti-RBD IgG, compared to healthy controls (P = .0349) and to cancer patients without a previous infection (P < .001). Vaccine type (anti-S1: P < .0001; anti-RBD: P = .0045), comorbidities (anti-S1: P = .0274; anti-RBD: P = .0048) and the use of G-CSF (anti-S1: P = .0151) negatively affected the antibody response. Conversely, previous exposure to SARS-CoV-2 significantly enhanced the response to vaccination (anti-S1: P < .0001; anti-RBD: P = .0026). Vaccine immunogenicity in cancer patients with a previous exposure to SARS-CoV-2 seems comparable to that of healthy subjects. On the other hand, clinical variables of immune frailty negatively affect humoral immune response to vaccination.


Assuntos
COVID-19 , Neoplasias , Humanos , Vacina BNT162 , Vacina de mRNA-1273 contra 2019-nCoV , COVID-19/prevenção & controle , Estudos Prospectivos , SARS-CoV-2 , Vacinas de mRNA , Anticorpos Antivirais , Vacinação , Neoplasias/terapia
6.
iScience ; 26(1): 105726, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36507220

RESUMO

Memory B cells (MBCs) generate rapid antibody responses upon secondary encounter with a pathogen. Here, we investigated the kinetics, avidity, and cross-reactivity of serum antibodies and MBCs in 155 SARS-CoV-2 infected and vaccinated individuals over a 16-month time frame. SARS-CoV-2-specific MBCs and serum antibodies reached steady-state titers with comparable kinetics in infected and vaccinated individuals. Whereas MBCs of infected individuals targeted both prefusion and postfusion Spike (S), most vaccine-elicited MBCs were specific for prefusion S, consistent with the use of prefusion-stabilized S in mRNA vaccines. Furthermore, a large fraction of MBCs recognizing postfusion S cross-reacted with human betacoronaviruses. The avidity of MBC-derived and serum antibodies increased over time resulting in enhanced resilience to viral escape by SARS-CoV-2 variants, including Omicron BA.1 and BA.2 sublineages, albeit only partially for BA.4 and BA.5 sublineages. Overall, the maturation of high-affinity and broadly reactive MBCs provides the basis for effective recall responses to future SARS-CoV-2 variants.

7.
bioRxiv ; 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36203553

RESUMO

Memory B cells (MBCs) generate rapid antibody responses upon secondary encounter with a pathogen. Here, we investigated the kinetics, avidity and cross-reactivity of serum antibodies and MBCs in 155 SARS-CoV-2 infected and vaccinated individuals over a 16-month timeframe. SARS-CoV-2-specific MBCs and serum antibodies reached steady-state titers with comparable kinetics in infected and vaccinated individuals. Whereas MBCs of infected individuals targeted both pre- and postfusion Spike (S), most vaccine-elicited MBCs were specific for prefusion S, consistent with the use of prefusion-stabilized S in mRNA vaccines. Furthermore, a large fraction of MBCs recognizing postfusion S cross-reacted with human betacoronaviruses. The avidity of MBC-derived and serum antibodies increased over time resulting in enhanced resilience to viral escape by SARS-CoV-2 variants, including Omicron BA.1 and BA.2 sub-lineages, albeit only partially for BA.4 and BA.5 sublineages. Overall, the maturation of high-affinity and broadly-reactive MBCs provides the basis for effective recall responses to future SARS-CoV-2 variants.

8.
Front Immunol ; 13: 850846, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371011

RESUMO

A relevant portion of patients with disease caused by the severe acute respiratory syndrome coronavirus 2 (COVID-19) experience negative outcome, and several laboratory tests have been proposed to predict disease severity. Among others, dramatic changes in peripheral blood cells have been described. We developed and validated a laboratory score solely based on blood cell parameters to predict survival in hospitalized COVID-19 patients. We retrospectively analyzed 1,619 blood cell count from 226 consecutively hospitalized COVID-19 patients to select parameters for inclusion in a laboratory score predicting severity of disease and survival. The score was derived from lymphocyte- and granulocyte-associated parameters and validated on a separate cohort of 140 consecutive COVID-19 patients. Using ROC curve analysis, a best cutoff for score of 30.6 was derived, which was associated to an overall 82.0% sensitivity (95% CI: 78-84) and 82.5% specificity (95% CI: 80-84) for detecting outcome. The scoring trend effectively separated survivor and non-survivor groups, starting 2 weeks before the end of the hospitalization period. Patients' score time points were also classified into mild, moderate, severe, and critical according to the symptomatic oxygen therapy administered. Fluctuations of the score should be recorded to highlight a favorable or unfortunate trend of the disease. The predictive score was found to reflect and anticipate the disease gravity, defined by the type of the oxygen support used, giving a proof of its clinical relevance. It offers a fast and reliable tool for supporting clinical decisions and, most important, triage in terms of not only prioritization but also allocation of limited medical resources, especially in the period when therapies are still symptomatic and many are under development. In fact, a prolonged and progressive increase of the score can suggest impaired chances of survival and/or an urgent need for intensive care unit admission.


Assuntos
COVID-19 , Humanos , Oxigênio , Curva ROC , Estudos Retrospectivos , SARS-CoV-2
9.
Int Immunopharmacol ; 100: 108081, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34461492

RESUMO

OBJECTIVE: Circulating lymphocyte subtypes are not fully explored parameters for monitoring chronic T cell activation during inflammatory bowel disease (IBD). Tumor necrosis factor α (TNFα), one of the main mediators of IBD related inflammation induces expression of CD70 on T cells. CD70 limits T cell expansion and controls CD27 receptor on activated B lymphocytes. Aim of this study was to assess the number and the frequency of CD70+ T cells and CD27+ B cells in IBD patients during inactive phase of the disease under or without anti-TNFα treatment. DESIGN: We studied 91 patients with inactive IBD, 31 untreated, 29 treated with infliximab (IFX), and 31 treated with adalimumab (ADA). Lymphocyte phenotypes were assessed by flow cytometry using anti-CD45, CD19, CD27, CD3, and CD70 monoclonal antibodies. IFX and ADA actual capacity of TNFα neutralization in serum was estimated by the recoveryELISA technique. RESULTS: Whereas CD3+ T cells were increased in treated compared to untreated patients, the percentage of the CD70+ T cells was significantly lower in treated patients indicating a 'cooling' effect of the biological therapy. This effect differs between samples according to the therapeutic range of the circulating drug. Although the CD19+ B-cell percentage tended to be lower in treated patients, CD19+27+ memory B cells did not show significant differences between groups. CONCLUSIONS: Frequency of peripheral blood CD70+ T cells was significantly reduced by treatment with anti-TNFα antibodies. Monitoring of this parameter of T cells can give better insight to the disease progression and therapy application in IBD patients.


Assuntos
Adalimumab/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/farmacologia , Linfócitos T/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab/uso terapêutico , Adulto , Idoso , Ligante CD27/análise , Ligante CD27/metabolismo , Complexo CD3/análise , Complexo CD3/metabolismo , Feminino , Humanos , Imunofenotipagem , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Infliximab/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Front Immunol ; 12: 682094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335583

RESUMO

Peripheral neutrophils in HIV-infected individuals are characterized by impairment of chemotaxis, phagocytosis, bactericidal activity, and oxidative burst ability regardless of whether patients are receiving antiretroviral therapy or not. Neutrophil dysfunction leads not only to increased susceptibility to opportunistic infections but also to tissue damage through the release of reactive oxygen species (ROS), proteases, and other potentially harmful effector molecules contributing to AIDS progression. In this study, we demonstrated high levels of histone H3 lysine K4 trimethylated (H3K4me3) and dysregulation of DNA transcription in circulating neutrophils of HIV-infected subjects. This dysregulation was accompanied by a deficient response of neutrophils to LPS, impaired cytokine/chemokine/growth factor synthesis, and increased apoptosis. Chromatin immunoprecipitation sequencing (ChIPseq) H3K4me3 histone analysis revealed that the most spectacular abnormalities were observed in the exons, introns, and promoter-TSS regions. Bioinformatic analysis of Gene Ontology, including biological processes, molecular function, and cellular components, demonstrated that the main changes were related to the genes responsible for cell activation, cytokine production, adhesive molecule expression, histone remodeling via upregulation of methyltransferase process, and downregulation of NF-κB transcription factor in canonical pathways. Abnormalities within H3K4me3 implicated LPS-mediated NF-κB canonical activation pathway that was a result of low amounts of κB DNA sites within histone H3K4me3, low NF-κB (p65 RelA) and TLR4 mRNA expression, and reduced free NF-κB (p65 RelA) accumulation in the nucleus. Genome-wide survey of H3K4me3 provided evidence that chromatin modifications lead to an impairment within the canonical NF-κB cell activation pathway causing the neutrophil dysfunction observed in HIV-infected individuals.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Infecções por HIV/etiologia , Infecções por HIV/metabolismo , Histonas/metabolismo , Interações Hospedeiro-Patógeno , Neutrófilos/imunologia , Neutrófilos/metabolismo , Adulto , Biomarcadores , Biologia Computacional/métodos , Suscetibilidade a Doenças/imunologia , Feminino , Infecções por HIV/patologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Anotação de Sequência Molecular , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Adulto Jovem
11.
Blood Transfus ; 19(3): 181-189, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33539289

RESUMO

BACKGROUND: The Milan metropolitan area in Northern Italy was among the most severely hit by the SARS-CoV-2 outbreak. The aim of this study was to examine the seroprevalence trends of SARS-CoV-2 in healthy asymptomatic adults, and the risk factors and laboratory correlates of positive tests. MATERIALS AND METHODS: We conducted a cross-sectional study in a random sample of blood donors, who were asymptomatic at the time of evaluation, at the beginning of the first phase (February 24th to April 8th 2020; n=789). Presence of IgM/IgG antibodies against the SARS-CoV-2-Nucleocapsid protein was assessed by a lateral flow immunoassay. RESULTS: The test had a 100/98.3 sensitivity/specificity (n=32/120 positive/negative controls, respectively), and the IgG test was validated in a subset by an independent ELISA against the Spike protein (n=34, p<0.001). At the start of the outbreak, the overall adjusted seroprevalence of SARS-CoV-2 was 2.7% (95% CI: 0.3-6%; p<0.0001 vs 120 historical controls). During the study period, characterised by a gradual implementation of social distancing measures, there was a progressive increase in the adjusted seroprevalence to 5.2% (95% CI: 2.4-9.0; 4.5%, 95% CI: 0.9-9.2% according to a Bayesian estimate) due to a rise in IgG reactivity to 5% (95% CI: 2.8-8.2; p=0.004 for trend), but there was no increase in IgM+ (p=not significant). At multivariate logistic regression analysis, IgG reactivity was more frequent in younger individuals (p=0.043), while IgM reactivity was more frequent in individuals aged >45 years (p=0.002). DISCUSSION: SARS-CoV-2 infection was already circulating in Milan at the start of the outbreak. The pattern of IgM/IgG reactivity was influenced by age: IgM was more frequently detected in participants aged >45 years. By the end of April, 2.4-9.0% of healthy adults had evidence of seroconversion.


Assuntos
Infecções Assintomáticas/epidemiologia , Doadores de Sangue/estatística & dados numéricos , COVID-19/epidemiologia , Pandemias , SARS-CoV-2/imunologia , Adulto , Fatores Etários , Anticorpos Antivirais/sangue , Teorema de Bayes , COVID-19/imunologia , Teste Sorológico para COVID-19/métodos , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Soroconversão , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia
12.
Front Immunol ; 12: 793191, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975897

RESUMO

Purpose: To compare SARS-CoV-2 antigen-specific antibody production and plasma neutralizing capacity against B.1 wild-type-like strain, and Gamma/P.1 and Delta/B.1.617.2 variants-of-concern, in subjects with different Covid-19 disease and vaccination histories. Methods: Adult subjects were: 1) Unvaccinated/hospitalized for Covid-19; 2) Covid-19-recovered followed by one BNT162b2 vaccine dose; and 3) Covid-19-naïve/2-dose BNT162b2 vaccinated. Multiplex Luminex® immunoassays measured IgG, IgA, and IgM plasma levels against SARS-CoV-2 receptor-binding domain (RBD), spike-1 (S), and nucleocapsid proteins. Neutralizing activity was determined in Vero E6 cytopathic assays. Results: Maximum anti-RBD IgG levels were similar in Covid-19­recovered individuals 8‒10 days after single-dose vaccination and in Covid-19-naïve subjects 7 days after 2nd vaccine dosing; both groups had ≈2­fold higher anti-RBD IgG levels than Unvaccinated/Covid-19 subjects tracked through 2 weeks post-symptom onset. Anti-S IgG expression patterns were similar to RBD within each group, but with lower signal strengths. Viral antigen-specific IgA and IgM levels were more variable than IgG patterns. Anti-nucleocapsid immunoglobulins were not detected in Covid-19-naïve subjects. Neutralizing activity against the B.1 strain, and Gamma/P.1 and Delta/B.1.617.2 variants, was highest in Covid­19-recovered/single-dose vaccinated subjects; although neutralization against the Delta variant in this group was only 26% compared to B.1 neutralization, absolute anti-Delta titers suggested maintained protection. Neutralizing titers against the Gamma and Delta variants were 33‒77% and 26‒67%, respectively, versus neutralization against the B.1 strain (100%) in the three groups. Conclusion: These findings support SARS-CoV-2 mRNA vaccine usefulness regardless of Covid-19 history, and confirm remarkable protection provided by a single vaccine dose in people who have recovered from Covid-19.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacina BNT162/imunologia , COVID-19/imunologia , Isotipos de Imunoglobulinas/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Vacina BNT162/administração & dosagem , COVID-19/virologia , Chlorocebus aethiops , Feminino , Humanos , Imunoensaio/métodos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Isotipos de Imunoglobulinas/sangue , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinação/métodos , Células Vero
13.
Cell ; 183(4): 1024-1042.e21, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32991844

RESUMO

Analysis of the specificity and kinetics of neutralizing antibodies (nAbs) elicited by SARS-CoV-2 infection is crucial for understanding immune protection and identifying targets for vaccine design. In a cohort of 647 SARS-CoV-2-infected subjects, we found that both the magnitude of Ab responses to SARS-CoV-2 spike (S) and nucleoprotein and nAb titers correlate with clinical scores. The receptor-binding domain (RBD) is immunodominant and the target of 90% of the neutralizing activity present in SARS-CoV-2 immune sera. Whereas overall RBD-specific serum IgG titers waned with a half-life of 49 days, nAb titers and avidity increased over time for some individuals, consistent with affinity maturation. We structurally defined an RBD antigenic map and serologically quantified serum Abs specific for distinct RBD epitopes leading to the identification of two major receptor-binding motif antigenic sites. Our results explain the immunodominance of the receptor-binding motif and will guide the design of COVID-19 vaccines and therapeutics.


Assuntos
Anticorpos Neutralizantes/imunologia , Mapeamento de Epitopos/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2 , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Reações Antígeno-Anticorpo , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Sítios de Ligação , COVID-19 , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Epitopos/química , Epitopos/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Cinética , Simulação de Dinâmica Molecular , Pandemias , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Ligação Proteica , Domínios Proteicos/imunologia , Estrutura Quaternária de Proteína , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
14.
J Med Virol ; 92(9): 1637-1640, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32222993

RESUMO

This report describes the isolation, molecular characterization, and phylogenetic analysis of the first three complete genomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) isolated from three patients involved in the first outbreak of COVID-19 in Lombardy, Italy. Early molecular epidemiological tracing suggests that SARS-CoV-2 was present in Italy weeks before the first reported cases of infection.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Genoma Viral , Genômica , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/genética , Biologia Computacional/métodos , Genômica/métodos , Humanos , Itália/epidemiologia , Análise de Regressão
15.
Cells ; 9(1)2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861635

RESUMO

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS) mediated by autoreactive lymphocytes. The role of autoreactive lymphocytes in the CNS demyelination is well described, whereas very little is known about their role in remyelination during MS remission. In this study, we identified a new subpopulation of myelin-specific CD49d+CD154+ lymphocytes presented in the peripheral blood of MS patients during remission, that proliferated in vitro in response to myelin peptides. These lymphocytes possessed the unique ability to migrate towards maturing oligodendrocyte precursor cells (OPCs) and synthetize proinflammatory chemokines/cytokines. The co-culture of maturing OPCs with myelin-specific CD49d+CD154+ lymphocytes was characterized by the increase in proinflammatory chemokine/cytokine secretion that was not only a result of their cumulative effect of what OPCs and CD49d+CD154+ lymphocytes produced alone. Moreover, maturing OPCs exposed to exogenous myelin peptides managed to induce CD40-CD154-dependent CD49d+CD154+ lymphocyte proliferation. We confirmed, in vivo, the presence of CD49d+CD154+ cells close to maturating OPCs and remyelinating plaque during disease remission in the MS mouse model (C57Bl/6 mice immunized with MOG35-55) by immunohistochemistry. Three weeks after an acute phase of experimental autoimmune encephalomyelitis, CD49d+/CD154+ cells were found to be co-localized with O4+ cells (oligodendrocyte progenitors) in the areas of remyelination identified by myelin basic protein (MBP) labelling. These data suggested that myelin-specific CD49d+CD154+ lymphocytes present in the brain can interfere with remyelination mediated by oligodendrocytes probably as a result of establishing proinflammatory environment.


Assuntos
Ligante de CD40/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Integrina alfa4/metabolismo , Esclerose Múltipla/imunologia , Bainha de Mielina/metabolismo , Adulto , Animais , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Linfócitos/citologia , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito/efeitos adversos , Células Precursoras de Oligodendrócitos/citologia , Células Precursoras de Oligodendrócitos/imunologia , Fragmentos de Peptídeos/efeitos adversos , Remielinização
16.
Cells ; 8(12)2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775315

RESUMO

The critical aspect in multiple sclerosis (MS) progression involves insufficient regeneration of CNS resulting from deficient myelin synthesis by newly generated oligodendrocytes (OLs). Although many studies have focused on the role of autoreactive lymphocytes in the inflammatory-induced axonal loss, the problem of insufficient remyelination and disease progression is still unsolved. To determine the effect of myelin-specific lymphocytes on OL function in MS patients and in a mouse model of MS, we cultured myelin induced MS CD49d+CD154+ circulating lymphocytes as well as Experimental Autoimmune Encephalomyelitis (EAE) mouse brain-derived T and memory B cells with maturing oligodendrocyte precursor cells (OPCs). We found that myelin-specific CD49d+CD154+ lymphocytes affected OPC maturation toward formation of immune reactive OLs. Newly generated OLs were characterized by imbalanced myelin basic protein (MBP) and proteolipid protein (PLP) production as well as proinflammatory chemokine/cytokine synthesis. The analysis of cellular pathways responsible for OL reprogramming revealed that CD49d+CD154+ lymphocytes affected miRNA synthesis by dysregulation of polymerase II activity. miR-665 and ELL3 turned out to be the main targets of MS myelin-specific lymphocytes. Neutralization of high intracellular miR-665 concentration restored miRNA and MBP/PLP synthesis. Together, these data point to new targets for therapeutic intervention promoting CNS remyelination.


Assuntos
Linfócitos , Esclerose Múltipla , Oligodendroglia , Remielinização , Adulto , Animais , Linhagem Celular , Feminino , Humanos , Linfócitos/imunologia , Linfócitos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Proteína Básica da Mielina/imunologia , Proteína Proteolipídica de Mielina/imunologia , Oligodendroglia/imunologia , Oligodendroglia/patologia , Fatores de Elongação da Transcrição/imunologia
17.
Cell Host Microbe ; 26(5): 623-637.e8, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31653484

RESUMO

Potent and broadly neutralizing antibodies (bnAbs) are the hallmark of HIV-1 protection by vaccination. The membrane-proximal external region (MPER) of the HIV-1 gp41 fusion protein is targeted by the most broadly reactive HIV-1 neutralizing antibodies. Here, we examine the structural and molecular mechansims of neutralization by anti-MPER bnAb, LN01, which was isolated from lymph-node-derived germinal center B cells of an elite controller and exhibits broad neutralization breadth. LN01 engages both MPER and the transmembrane (TM) region, which together form a continuous helix in complex with LN01. The tilted TM orientation allows LN01 to interact simultaneously with the peptidic component of the MPER epitope and membrane via two specific lipid binding sites of the antibody paratope. Although LN01 carries a high load of somatic mutations, most key residues interacting with the MPER epitope and lipids are germline encoded, lending support for the LN01 epitope as a candidate for lineage-based vaccine development.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/imunologia , Vacinas contra a AIDS/imunologia , Sequência de Aminoácidos/genética , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Domínios Proteicos/imunologia
18.
Sci Rep ; 7: 42470, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28211903

RESUMO

Several studies demonstrated a relevant role of polymorphisms located within the HLA-B and -C loci and the Killer Immunoglobulin Receptors (KIRs) 3DL1 and 3DS1 in controlling HIV-1 replication. KIRs are regulatory receptors expressed at the surface of NK and CD8+ T-cells that specifically bind HLA-A and -B alleles belonging to the Bw4 supratype and all the -C alleles expressing the C1 or C2 supratype. We here disclose a novel signature associated with the Elite Controller but not with the long-term nonprogressor status concerning 2DS activating KIRs and HLA-C2 alleles insensitive to miRNA148a regulation. Overall, our findings support a crucial role of NK cells in the control of HIV-1 viremia.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/imunologia , Antígenos HLA-C/imunologia , Interações Hospedeiro-Patógeno/imunologia , Receptores KIR/agonistas , Alelos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Cromossomos Humanos Par 19 , Cromossomos Humanos Par 6 , Progressão da Doença , Predisposição Genética para Doença , Genótipo , Infecções por HIV/genética , Antígenos HLA-C/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Interações Hospedeiro-Patógeno/genética , Humanos , Razão de Chances , Polimorfismo Genético , Receptores KIR/genética , Receptores KIR/metabolismo
19.
AIDS Res Hum Retroviruses ; 29(1): 142-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22775001

RESUMO

The present study aimed to evaluate the role of genetic polymorphisms in the emergence of lipoatrophy or lipodystrophy in HIV-infected patients with antiretroviral therapy (ART) in Thailand. Position 455 upstream of the Apolipoprotein C3 gene (ApoC3 T-455C, rs2854116), codon 64 of the Beta3 adrenergic receptor gene (ARß3 Tcod64C, rs4994), and position 670 upstream of the Fas gene (Fas A-670G, rs1800682) were genotyped in 829 HIV-infected Thai patients who had started ART. Crude and adjusted incidence rate ratios (IRR) were calculated using Poisson regression. The serum levels of cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were also analyzed. Multivariate analysis revealed an association between the Fas -670AA genotype, but not the ApoC3 -455 or ARß3 cod64 genotypes, with the incidence of lipoatrophy after adjusting for gender and stavudine (d4T)-containing regimens (IRR=1.72, 95% CI=1.20-2.45, p=0.003). However, ApoC3 -455C homozygous patients showed elevated serum levels of triglycerides, while this genotype did not affect serum total cholesterol, HDL, or LDL levels in patients with lipoatrophy or lipodystrophy. In contrast, the ARß3 cod64 genotype did not show any significant association with the serum levels of cholesterol, triglycerides, HDL, or LDL. In conclusion, Fas -670AA affected the incidence of lipoatrophy in HIV-1-infected Thai patients, while the ApoC3 -455C allele affected the serum levels of triglycerides. These results confirmed the role of genetics in the development of ART-related metabolic disorders.


Assuntos
Proteína Ligante Fas/genética , Síndrome de Lipodistrofia Associada ao HIV/genética , Adulto , Apolipoproteína C-III/genética , Povo Asiático/genética , Povo Asiático/estatística & dados numéricos , Colesterol/sangue , Feminino , Genótipo , HIV-1 , Síndrome de Lipodistrofia Associada ao HIV/sangue , Síndrome de Lipodistrofia Associada ao HIV/epidemiologia , Homozigoto , Humanos , Incidência , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores Adrenérgicos beta 3/genética , Tailândia/epidemiologia , Triglicerídeos/sangue
20.
J Antimicrob Chemother ; 67(9): 2236-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22661571

RESUMO

OBJECTIVES: Hyperbilirubinaemia is a frequent complication of atazanavir-containing antiretroviral therapy and its severity is related to UDP-glucuronosyl transferase (UGT) 1A1*28 polymorphism. The aim of this study was to evaluate the safety and outcome of unboosted atazanavir-containing regimens based on the genetic constitution. METHODS: Fifty-one HIV-1-infected patients on boosted atazanavir were prospectively enrolled in the study. Twenty-five patients with a UGT1A1*28 allele switched to 400 mg of unboosted atazanavir. RESULTS: At baseline, UGT1A1 heterozygous and homozygous patients had significantly higher bilirubin levels than wild-type (P = 0.012 and P < 0.001, respectively). After ritonavir removal, a reduction was observed in total bilirubin (from 4.09 to 1.82 mg/dL; P < 0.001), γ-glutamyl transpeptidase (P = 0.015), triglycerides (P = 0.03) and total cholesterol (P = 0.05). No significant changes in CD4 T cell count and no increases in viral load were observed 12 months after unboosting. Plasma drug monitoring after ritonavir removal revealed the presence of therapeutic atazanavir concentrations in all patients except one with poor therapy adherence. CONCLUSIONS: UGT1A1*28 is significantly related to hyperbilirubinaemia in HIV-1 patients receiving atazanavir. Genotyping before the initiation of antiretroviral therapy can reduce the emergence of severe hyperbilirubinaemia. Unboosted atazanavir-containing therapy is safe and efficacious in patients with an undetectable viral load with a UGT1A1*28 polymorphism, allowing the use of atazanavir in patients otherwise likely unable to receive it.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Bilirrubina/sangue , Glucuronosiltransferase/genética , Infecções por HIV/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Oligopeptídeos/efeitos adversos , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Triglicerídeos/sangue , Adulto , Fármacos Anti-HIV/efeitos adversos , Sulfato de Atazanavir , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Estudos Prospectivos , Resultado do Tratamento
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