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1.
BMJ Open ; 14(3): e080501, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485477

RESUMO

BACKGROUND: Invasive non-typhoidal Salmonella (iNTS) disease is a significant health concern in sub-Saharan Africa. While our knowledge of a larger-scale variation is growing, understanding of the subnational variation in iNTS disease occurrence is lacking, yet crucial for targeted intervention. METHOD: We performed a systematic review of reported occurrences of iNTS disease in sub-Saharan Africa, consulting literature from PubMed, Embase and Web of Science published since 2000. Eligibility for inclusion was not limited by study type but required that studies reported original data on human iNTS diseases based on the culture of a normally sterile site, specifying subnational locations and the year, and were available as full-text articles. We excluded studies that diagnosed iNTS disease based on clinical indications, cultures from non-sterile sites or serological testing. We estimated the probability of occurrence of iNTS disease for sub-Saharan Africa on 20 km × 20 km grids by exploring the association with geospatial covariates such as malaria, HIV, childhood growth failure, access to improved water, and sanitation using a boosted regression tree. RESULTS: We identified 130 unique references reporting human iNTS disease in 21 countries published from 2000 through 2020. The estimated probability of iNTS occurrence grids showed significant spatial heterogeneity at all levels (20 km × 20 km grids, subnational, country and subregional levels) and temporal heterogeneity by year. For 2020, the probability of occurrence was higher in Middle Africa (0.34, 95% CI: 0.25 to 0.46), followed by Western Africa (0.33, 95% CI: 0.23 to 0.44), Eastern Africa (0.24, 95% CI: 0.17 to 0.33) and Southern Africa (0.08, 95% CI: 0.03 to 0.11). Temporal heterogeneity indicated that the probability of occurrence increased between 2000 and 2020 in countries such as the Republic of the Congo (0.05 to 0.59) and Democratic Republic of the Congo (0.10 to 0.48) whereas it decreased in countries such as Uganda (0.65 to 0.23) or Zimbabwe (0.61 to 0.37). CONCLUSION: The iNTS disease occurrence varied greatly across sub-Saharan Africa, with certain regions being disproportionately affected. Exploring regions at high risk for iNTS disease, despite the limitations in our data, may inform focused resource allocation. This targeted approach may enhance efforts to combat iNTS disease in more affected areas.


Assuntos
Malária , Infecções por Salmonella , Febre Tifoide , Humanos , Criança , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/complicações , Salmonella , Malária/epidemiologia , África Subsaariana/epidemiologia
2.
Expert Rev Vaccines ; 23(1): 432-444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517153

RESUMO

BACKGROUND: Heterologous prime-boost schedules have been employed in SARS-CoV-2 vaccination, yet additional data on immunogenicity and effectiveness are still needed. RESEARCH DESIGN AND METHODS: Here, we measured the immunogenicity and effectiveness in the real-world setting of the mRNA booster dose in 181 subjects who had completed primary vaccination with ChAdOx1, BNT162b2, or mRNA1273 vaccines (IMMUNO_COV study; protocol code 18,869). The spike-specific antibody and B cell responses were analyzed up to 6 months after boosting. RESULTS: After an initial slower antibody response, the heterologous ChAdOx1/mRNA prime-boost formulation elicited spike-specific IgG titers comparable to homologous approaches, while spike-specific B cells showed a higher percentage of CD21-CD27- atypical cells compared to homologous mRNA vaccination. Mixed combinations of BNT162b2 and mRNA-1273 elicited an immune response comparable with homologous strategies. Non-significant differences in the Relative Risk of infection, calculated over a period of 18 months after boosting, were reported among homologous or heterologous vaccination groups, indicating a comparable relative vaccine effectiveness. CONCLUSIONS: Our data endorse the heterologous booster vaccination with mRNA as a valuable alternative to homologous schedules. This approach can serve as a solution in instances of formulation shortages and contribute to enhancing vaccine strategies for potential epidemics or pandemics.


Assuntos
COVID-19 , Vacinas , Humanos , SARS-CoV-2 , Vacina BNT162 , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Vacinação , Vacina de mRNA-1273 contra 2019-nCoV , Pandemias , RNA Mensageiro , Adenoviridae , Anticorpos Antivirais , Anticorpos Neutralizantes
3.
Microorganisms ; 11(10)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37894265

RESUMO

Recurrence of coronavirus disease 19 (COVID-19) symptoms and SARS-CoV-2 viral load relapse have been reported in people treated with nirmatrelvir/ritonavir (NM/r). However, little is understood about the etiology of this phenomenon. Our aim was to investigate the relation between the host's immune response and viral rebound. We described three cases of COVID-19 rebound that occurred after treatment with nirmatrelvir/ritonavir (group A). In addition, we compared spike-specific antibody response and plasma cytokine/chemokine patterns of the rebound cases with those of (i) control patients treated with nirmatrelvir/ritonavir who did not show rebound (group B), and (ii) subjects not treated with any anti-SARS-CoV-2 drug (group C). The anti-spike antibodies and plasma cytokines/chemokines were similar in groups A and B. However, we observed a higher anti-BA.2 spike IgG response in patients without antiviral treatment (group C) [geometric mean titer 210,807, 5.1- and 8.2-fold higher compared to group A (p = 0.039) and group B (p = 0.032)]. Moreover, the patients receiving antiviral treatment (groups A-B) showed higher circulating levels of platelet-derived growth factor subunit B (PDGF-BB) and vascular endothelial growth Factors (VEGF) and lower levels of interleukin-9 (IL-9), interleukine-1 receptor antagonist (IL-1 RA), and regulated upon activation normal T cell expressed and presumably secreted chemokine (RANTES) when compared to group C. In conclusion, we observed lower anti-spike IgG levels and different cytokine patterns in nirmatrelvir/ritonavir-treated patients compared to those not treated with anti-SARS-CoV-2 drugs. This suggests that early antiviral treatment, by reducing viral load and antigen presentation, could mitigate the immune response against SARS-CoV-2. The clinical relevance of such observation should be further investigated in larger populations.

4.
Antibiotics (Basel) ; 12(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37627650

RESUMO

Enterococcus hirae is a rare pathogen in human infections, although its incidence may be underestimated due to its difficult isolation. We describe the first known case of E. hirae infective endocarditis (IE), which involves the mitral valve alone, and the seventh E. hirae IE worldwide. Case presentation: a 62-year-old male was admitted to our department with a five-month history of intermittent fever without responding to antibiotic treatment. His medical history included mitral valve prolapse, recent pleurisy, and lumbar epidural steroid injections due to lumbar degenerative disc disease. Pre-admission transesophageal echocardiography (TEE) showed mitral valve vegetation, and Enterococcus faecium was isolated on blood cultures by MALDI-TOF VITEK MS. During hospitalization, intravenous (IV) therapy with ampicillin and ceftriaxone was initiated, and E. hirae was identified by MALDI-TOF Bruker Biotyper on three blood culture sets. A second TEE revealed mitral valve regurgitation, which worsened due to infection progression. The patient underwent mitral valve replacement with a bioprosthetic valve and had an uncomplicated postoperative course; he was discharged after six weeks of IV ampicillin and ceftriaxone treatment.

5.
Int J Mol Sci ; 24(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37628844

RESUMO

Molecular and cellular research in the field of endometriosis is moving forward in giant steps [...].


Assuntos
Endometriose , Feminino , Humanos , Endometriose/genética
6.
Cells ; 12(13)2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37443740

RESUMO

The mRNA vaccines for SARS-CoV-2 have demonstrated efficacy and immunogenicity in the real-world setting. However, most of the research on vaccine immunogenicity has been centered on characterizing the antibody response, with limited exploration into the persistence of spike-specific memory B cells. Here we monitored the durability of the memory B cell response up to 9 months post-vaccination, and characterized the trajectory of spike-specific B cell phenotypes in healthy individuals who received two doses of the BNT162b2 vaccine. To profile the spike-specific B cell response, we applied the tSNE and Cytotree automated approaches. Spike-specific IgA+ and IgG+ plasmablasts and IgA+ activated cells were observed 7 days after the second dose and disappeared 3 months later, while subsets of spike-specific IgG+ resting memory B cells became predominant 9 months after vaccination, and they were capable of differentiating into spike-specific IgG secreting cells when restimulated in vitro. Other subsets of spike-specific B cells, such as IgM+ or unswitched IgM+IgD+ or IgG+ double negative/atypical cells, were also elicited by the BNT162b2 vaccine and persisted up to month 9. The analysis of circulating spike-specific IgG, IgA, and IgM was in line with the plasmablasts observed. The longitudinal analysis of the antigen-specific B cell response elicited by mRNA-based vaccines provides valuable insights into our understanding of the immunogenicity of this novel vaccine platform destined for future widespread use, and it can help in guiding future decisions and vaccination schedules.


Assuntos
Vacina BNT162 , COVID-19 , Humanos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinas de mRNA , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M
7.
Commun Med (Lond) ; 3(1): 13, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717688

RESUMO

BACKGROUND: Limited longitudinal data are available on immune response to mRNA SARS-CoV-2 vaccination in people living with HIV (PLWHIV); therefore, new evidence on induction and persistence of spike-specific antibodies and B cells is needed. METHODS: In this pilot study we investigated the spike-specific humoral and B cell responses up to six months after vaccination with two doses of mRNA vaccines in 84 PLWHIV under antiretroviral therapy compared to 79 healthy controls (HCs). RESULTS: Spike-specific IgG persisted six months in PLWHIV with no significant differences compared to HCs, even though a significantly lower IgG response was observed in patients with CD4+ T cells < 350/mmc. The frequency of subjects with antibodies capable of inhibiting ACE2/RBD binding was comparable between PLWHIV and HCs a month after the second vaccine dose, then a higher drop was observed in PLWHIV. A comparable percentage of spike-specific memory B cells was observed at month six in PLWHIV and HCs. However, PLWHIV showed a higher frequency of spike-specific IgD- CD27- double-negative memory B cells and a significantly lower rate of IgD- CD27+ Ig-switched memory B cells compared to HCs, suggesting a reduced functionality of the antigen-specific memory B population. CONCLUSIONS: The mRNA vaccination against SARS-CoV-2 elicits humoral and B cell responses quantitatively similar between PLWHIV and HCs, but there are important differences in terms of antibody functionality and phenotypes of memory B cells, reinforcing the notion that tailored vaccination policies should be considered for these patients.


SARS-CoV-2 vaccination has been demonstrated to protect people from severe COVID-19 and death. This is achieved through the induction of a specific immune response that recognizes and responds to the virus. Limited data are available on the immune response to SARS-CoV-2 vaccination in people living with HIV (PLWHIV). In this study, we evaluated the immune response up to six months after vaccination with two doses of vaccines in PLWHIV being treated with the standard antiretroviral therapy. We show that the immune response observed in PLWHIV is broadly similar to that in healthy subjects but that there are some differences in the cells induced as part of the immune response. We therefore suggest that specific vaccination policies should be considered for these PLWHIV.

8.
Front Immunol ; 13: 1017863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248803

RESUMO

Vaccination against SARS-CoV-2 using mRNA-based vaccines has been highly recommended for fragile subjects, including myelofibrosis patients (MF). Available data on the immune responsiveness of MF patients to mRNA SARS-CoV-2 vaccination, and the impact of the therapy with the JAK inhibitor ruxolitinib, are still fragmented. Here, we profile the spike-specific IgG and memory B-cell response in MF patients, treated or not with ruxolitinib, after the second and the third dose of SARS-CoV-2 BNT162b2 (BioNTech) and mRNA-1273 (Moderna) vaccines. Plasma and peripheral blood mononuclear cells samples were collected before vaccination, post the second and the third doses and tested for spike-specific antibodies, ACE2/RBD antibody inhibition binding activity and spike-specific B cells. The third vaccine dose significantly increased the spike-specific IgG titers in both ruxolitinib-treated and untreated patients, and strongly enhanced the percentage of subjects with antibodies capable of in vitro blocking ACE2/RBD interaction, from 50% up to 80%. While a very low frequency of spike-specific B cells was measured in blood 7 days after the second vaccination dose, a strong and significant increase was elicited by the third dose administration, generating a B cell response similar to the one detected in healthy controls. Despite the overall positive impact of the third dose in MF patients, two patients that were under active concomitant immunosuppressive treatment at the time of vaccination, and a patient that received lymphodepleting therapies in the past, remained low responders. The third mRNA vaccine dose strongly increases the SARS-CoV-2 specific humoral and B cell responses in MF patients, promoting a reactivation of the immune response similar to the one observed in healthy controls.


Assuntos
COVID-19 , Inibidores de Janus Quinases , Mielofibrose Primária , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais , Enzima de Conversão de Angiotensina 2 , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunoglobulina G , Leucócitos Mononucleares , Células B de Memória , Nitrilas , Pirazóis , Pirimidinas , RNA Mensageiro , SARS-CoV-2 , Vacinas Sintéticas , Vacinas de mRNA
9.
Front Cell Infect Microbiol ; 12: 869763, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795182

RESUMO

The in vitro stimulation of immune system cells with live or killed bacteria is essential for understanding the host response to pathogens. In the present study, we propose a model combining transcriptomic and cytokine assays on murine splenocytes to describe the immune recall in the days following pneumococcal lung infection. Mice were sacrificed at days 1, 2, 4, and 7 after Streptococcus pneumoniae (TIGR4 serotype 4) intranasal infection and splenocytes were cultured in the presence or absence of the same inactivated bacterial strain to access the transcriptomic and cytokine profiles. The stimulation of splenocytes from infected mice led to a higher number of differentially expressed genes than the infection or stimulation alone, resulting in the enrichment of 40 unique blood transcription modules, including many pathways related to adaptive immunity and cytokines. Together with transcriptomic data, cytokines levels suggested the presence of a recall immune response promoting both innate and adaptive immunity, stronger from the fourth day after infection. Dimensionality reduction and feature selection identified key variables of this recall response and the genes associated with the increase in cytokine concentrations. This model could study the immune responses involved in pneumococcal infection and possibly monitor vaccine immune response and experimental therapies efficacy in future studies.


Assuntos
Infecções Pneumocócicas , Infecções Respiratórias , Animais , Citocinas/metabolismo , Memória Imunológica , Camundongos , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas , Baço , Streptococcus pneumoniae/genética , Transcriptoma
11.
J Periodontol ; 93(6): 911-923, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34453748

RESUMO

BACKGROUND: The aim of this study is to clinically and molecularly evaluate the effect of an interproximal iuxta/subgingival direct composite restoration on periodontal tissue healing. METHODS: Individuals in need of a posterior iuxta/subgingival interproximal restoration were consecutively enrolled. After enrollment, a test (site with tooth decay) and a control site (intact contralateral tooth) were identified. After a periodontal examination (probing depth [PD], clinical attachment level, recession, plaque, and bleeding on probing [BOP]) and a sampling of gingival crevicular fluid, the composite restoration was performed (T0 ). Clinical and molecular assessments were repeated at 3 (T3 ), 6 (T6 ), and 12 (T12 ) months after the restoration. Intragroup pre-post comparisons for quantitative variables were performed either through one-way ANOVA or Kruskal-Wallis test. A multivariate linear regression analysis was then modeled. With α = 0.05, a power of 80% will be reached with the inclusion of 41 individuals. RESULTS: Biometric parameters demonstrated an increased mean PD (ΔPDT0 -T12 = -0.83 mm; P = 0.001) and loss of attachment (AL) (ΔCALT0 -T12 = -0.91 mm; P = 0.005) in the test site at 12 months. Accordingly, in the final multivariate regression model the radiographic distance between the bone crest and the restorative margin at baseline accounted for the dependent variable "attachment loss (AL)" (ΔCALT0 -T12 ) (P <0.05). CONCLUSIONS: Iuxta/subgingival interproximal restorative margins jeopardized clinically and molecularly the periodontal tissue healing at least up to 1 year of follow-up.


Assuntos
Placa Dentária , Periodonto , Citocinas , Índice de Placa Dentária , Líquido do Sulco Gengival , Humanos , Perda da Inserção Periodontal
12.
Biomedicines ; 9(10)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34680595

RESUMO

Immunization with mRNA SARS-CoV-2 vaccines has been highly recommended and prioritized in fragile subjects, including patients with myelofibrosis (MF). Available data on the vaccine immune response developed by MF patients and the impact of ruxolitinib treatment are still too fragmented to support an informed decision on a third dose for this category of subjects. Here, we show that 76% of MF patients develop spike-specific IgG after the second mRNA SARS-CoV-2 vaccine dose, but the response has a slower kinetics compared to healthy subjects, suggesting a reduced capability of their immune system to promptly react to vaccination. A reduced ACE2/RBD binding inhibition activity of spike-specific antibodies was also observed, especially in ruxolitinib-treated patients. Our results, showing slow kinetics of antibody responses in MF patients following vaccination with mRNA SARS-CoV-2 vaccines, support the need for a third vaccine dose.

13.
Front Immunol ; 12: 740708, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650563

RESUMO

SARS-CoV-2 mRNA vaccines have demonstrated high efficacy and immunogenicity, but limited information is currently available on memory B cell generation and long-term persistence. Here, we investigated spike-specific memory B cells and humoral responses in 145 subjects, up to 6 months after the BNT162b2 vaccine (Comirnaty) administration. Spike-specific antibodies peaked 7 days after the second dose and significant antibody titers and ACE2/RBD binding inhibiting activity were still observed after 6 months, despite a progressive decline over time. Concomitant to antibody reduction, spike-specific memory B cells, mostly IgG class-switched, increased in the blood of vaccinees and persisted 6 months after vaccination. Following the in vitro restimulation, circulating memory B cells reactivated and produced spike-specific antibodies. A high frequency of spike-specific IgG+ plasmablasts, identified by computational analysis 7 days after boost, positively correlated with the generation of IgG+ memory B cells at 6 months. These data demonstrate that mRNA BNT162b2 vaccine elicits strong B cell immunity with spike-specific memory B cells that still persist 6 months after vaccination, playing a crucial role for a rapid response to SARS-CoV-2 virus encounter.


Assuntos
Linfócitos B/imunologia , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas Sintéticas/administração & dosagem , Adulto , Idoso , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Vacina BNT162 , Feminino , Humanos , Imunoglobulina G/sangue , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Adulto Jovem , Vacinas de mRNA
14.
J Infect ; 83(5): 523-532, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34260964

RESUMO

OBJECTIVES: We sought to collate and summarize high-quality data on non-typhoidal Salmonella invasive disease (iNTS) incidence to provide contemporary incidence estimates by location and year. METHODS: We systematically searched the databases Embase + MEDLINE, Web of Science, and PubMed for articles published on the incidence of iNTS from inception of the database through 8 May 2020 with no language, country, date, or demographic restrictions applied. A meta-analysis was performed to report pooled iNTS incidence as a rate of cases per 100,000 per year. RESULTS: Among 13 studies eligible for analysis, there were 68 estimates of incidence. Overall pooled incidence (95% CI) was 44.8 (31.5-60.5) per 100,000 persons per year. When stratified by region, pooled incidence was significantly higher in Africa than Asia, 51.0 (36.3-68.0) compared to 1.0 (0.2-2.5), respectively. Incidence was consistently higher in children aged <5 years compared with older age groups. Incidence displayed considerable heterogeneity in both place and time, varying substantially between locations and over consecutive years in the same location. CONCLUSIONS: iNTS incidence varies by region, location, age group, and over time. Concerted efforts are needed to address the limited high-quality data available on iNTS disease incidence.


Assuntos
Infecções por Salmonella , África/epidemiologia , Idoso , Ásia , Criança , Humanos , Incidência , Salmonella , Infecções por Salmonella/epidemiologia
15.
Vaccines (Basel) ; 9(5)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065899

RESUMO

Salmonella Typhimurium (STm) represents the most prevalent cause of invasive non-typhoidal Salmonella (iNTS) disease, and currently no licensed vaccine is available. In this work we characterized the long-term anti-bacterial immunity elicited by a STm vaccine based on Generalized Modules of Membrane Antigens (GMMA) delivering O:4,5 antigen, using a murine model of systemic infection. Subcutaneous immunization of mice with STmGMMA/Alhydrogel elicited rapid, high, and persistent antigen-specific serum IgG and IgM responses. The serum was bactericidal in vitro. O:4,5-specific IgG were also detected in fecal samples after immunization and positively correlated with IgG observed in intestinal washes. Long-lived plasma cells and O:4,5-specific memory B cells were detected in spleen and bone marrow. After systemic STm challenge, a significant reduction of bacterial load in blood, spleen, and liver, as well as a reduction of circulating neutrophils and G-CSF glycoprotein was observed in STmGMMA/Alhydrogel immunized mice compared to untreated animals. Taken together, these data support the development of a GMMA-based vaccine for prevention of iNTS disease.

16.
Vaccines (Basel) ; 9(3)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804604

RESUMO

Characterizing the impact of the vaccination schedule on the induction of B and T cell immune responses is critical for improving vaccine immunogenicity. Here we compare the effect of a short (4 weeks) or a long (18 weeks) interval between priming and boosting in mice, using a model vaccine formulation based on the chimeric tuberculosis vaccine antigen H56 combined with alum. While no significant difference was observed in serum antigen-specific IgG response and the induction of antigen-specific T follicular helper cells into draining lymph nodes after the two immunization schedules, a longer interval between priming and boosting elicited a higher number of germinal center-B cells and H56-specific antibody-secreting cells and modulated the effector function of reactivated CD4+ T cells. These data show that the scheduling of the booster immunization could affect the immune response elicited by vaccination modulating and improving the immunogenicity of the vaccine.

17.
Cytometry A ; 97(3): 259-267, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31710181

RESUMO

The generation of the B cell response upon vaccination is characterized by the induction of different functional and phenotypic subpopulations and is strongly dependent on the vaccine formulation, including the adjuvant used. Here, we have profiled the different B cell subsets elicited upon vaccination, using machine learning methods for interpreting high-dimensional flow cytometry data sets. The B cell response elicited by an adjuvanted vaccine formulation, compared to the antigen alone, was characterized using two automated methods based on clustering (FlowSOM) and dimensional reduction (t-SNE) approaches. The clustering method identified, based on multiple marker expression, different B cell populations, including plasmablasts, plasma cells, germinal center B cells and their subsets, while this profiling was more difficult with t-SNE analysis. When undefined phenotypes were detected, their characterization could be improved by integrating the t-SNE spatial visualization of cells with the FlowSOM clusters. The frequency of some cellular subsets, in particular plasma cells, was significantly higher in lymph nodes of mice primed with the adjuvanted formulation compared to antigen alone. Thanks to this automatic data analysis it was possible to identify, in an unbiased way, different B cell populations and also intermediate stages of cell differentiation elicited by immunization, thus providing a signature of B cell recall response that can be hardly obtained with the classical bidimensional gating analysis. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.


Assuntos
Subpopulações de Linfócitos B , Vacinas , Adjuvantes Imunológicos , Animais , Análise por Conglomerados , Citometria de Fluxo , Camundongos
18.
Front Immunol ; 10: 2661, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798589

RESUMO

Current influenza vaccines manufactured using eggs have considerable limitations, both in terms of scale up production and the potential impact passaging through eggs can have on the antigenicity of the vaccine virus strains. Alternative methods of manufacture are required, particularly in the context of an emerging pandemic strain. Here we explore the production of recombinant influenza haemagglutinin using the ciliated protozoan Tetrahymena thermophila. For the first time we were able to produce haemagglutinin from both seasonal influenza A and B strains. This ciliate derived material was immunogenic, inducing an antibody response in both mice and non-human primates. Mice immunized with ciliate derived haemagglutinin were protected against challenge with homologous influenza A or B viruses. The antigen could also be combined with submicron particles containing a Nod2 ligand, significantly boosting the immune response and reducing the dose of antigen required. Thus, we show that Tetrahymena can be used as a manufacturing platform for viral vaccine antigens.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Tetrahymena thermophila/genética , Animais , Anticorpos Antivirais/biossíntese , Cães , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/biossíntese , Macaca , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Proteína Adaptadora de Sinalização NOD2/administração & dosagem , Poliésteres/administração & dosagem , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia
19.
Front Immunol ; 9: 1248, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922291

RESUMO

Transcriptomic profiling of the immune response induced by vaccine adjuvants is of critical importance for the rational design of vaccination strategies. In this study, transcriptomics was employed to profile the effect of the vaccine adjuvant used for priming on the immune response following re-exposure to the vaccine antigen alone. Mice were primed with the chimeric vaccine antigen H56 of Mycobacterium tuberculosis administered alone or with the CAF01 adjuvant and boosted with the antigen alone. mRNA sequencing was performed on blood samples collected 1, 2, and 7 days after priming and after boosting. Gene expression analysis at day 2 after priming showed that the CAF01 adjuvanted vaccine induced a stronger upregulation of the innate immunity modules compared with the unadjuvanted formulation. The immunostimulant effect of the CAF01 adjuvant, used in the primary immunization, was clearly seen after a booster immunization with a low dose of antigen alone. One day after boost, we observed a strong upregulation of multiple genes in blood of mice primed with H56 + CAF01 compared with mice primed with the H56 alone. In particular, blood transcription modules related to innate immune response, such as monocyte and neutrophil recruitment, activation of antigen-presenting cells, and interferon response were activated. Seven days after boost, differential expression of innate response genes faded while a moderate differential expression of T cell activation modules was appreciable. Indeed, immunological analysis showed a higher frequency of H56-specific CD4+ T cells and germinal center B cells in draining lymph nodes, a strong H56-specific humoral response and a higher frequency of antibody-secreting cells in spleen of mice primed with H56 + CAF01. Taken together, these data indicate that the adjuvant used for priming strongly reprograms the immune response that, upon boosting, results in a stronger recall innate response essential for shaping the downstream adaptive response.


Assuntos
Perfilação da Expressão Gênica , Imunidade/genética , Memória Imunológica , Transcriptoma , Vacinas/imunologia , Adjuvantes Imunológicos , Animais , Biologia Computacional/métodos , Feminino , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Imunidade Celular/genética , Imunidade Humoral/genética , Imunidade Inata/genética , Imunização , Imunização Secundária , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Camundongos , Vacinas contra a Tuberculose/administração & dosagem , Vacinas contra a Tuberculose/imunologia , Vacinação , Vacinas/administração & dosagem
20.
Front Immunol ; 9: 380, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29593710

RESUMO

The induction and modulation of the immune response to vaccination can be rationally designed by combining different vaccine formulations for priming and boosting. Here, we investigated the impact of heterologous prime-boost approaches on the vaccine-specific cellular and humoral responses specific for a mycobacterial vaccine antigen. C57BL/6 mice were primed with the chimeric vaccine antigen H56 administered alone or with the CAF01 adjuvant, and boosted with H56 alone, or combined with CAF01 or with the squalene-based oil-in-water emulsion adjuvant (o/w squalene). A strong secondary H56-specific CD4+ T cell response was recalled by all the booster vaccine formulations when mice had been primed with H56 and CAF01, but not with H56 alone. The polyfunctional nature of T helper cells was analyzed and visualized with the multidimensional flow cytometry FlowSOM software, implemented as a package of the R environment. A similar cytokine profile was detected in groups primed with H56 + CAF01 and boosted with or without adjuvant, except for some clusters of cells expressing high level of IL-17 together with TNF-α, IL-2, and IFN-γ, that were significantly upregulated only in groups boosted with the adjuvants. On the contrary, the comparison between groups primed with or without the adjuvant showed a completely different clusterization of cells, strengthening the impact of the formulation used for primary immunization on the profiling of responding cells. The presence of the CAF01 adjuvant in the priming formulation deeply affected also the secondary humoral response, especially in groups boosted with H56 alone or o/w squalene. In conclusion, the presence of CAF01 adjuvant in the primary immunization is crucial for promoting primary T and B cell responses that can be efficiently reactivated by booster immunization also performed with antigen alone.


Assuntos
Adjuvantes Imunológicos , Vacinas Bacterianas/imunologia , Infecções por Mycobacterium/imunologia , Mycobacterium/imunologia , Proteínas Recombinantes de Fusão/imunologia , Esqualeno/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Sistema Imunitário , Imunização Secundária , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL
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