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1.
Gerontology ; 69(7): 799-808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36863327

RESUMO

After the first wave of the COVID-19 pandemic, during which the severity of the disease in certain countries was attributed to a lack of basic education of the inhabitants, the authors of this paper initiated a literature review of educational trajectories, health, and ageing well. The findings strongly demonstrate that alongside genetics, the affective and educational family environment, as well as the general environment, greatly interact starting from the very first days of life. Thus, epigenetics plays a major role in the determination of health and disease [DOHAD] in the first 1,000 days of life as well as in the characterization of gender. Other factors such as socio-economic level, parental education, schooling in urban or rural areas, also play a major role in the differential acquisition of health literacy. This determines adherence (or lack thereof) to healthy lifestyles, risky behaviours, substance abuse, but also compliance with hygiene rules, and adherence to vaccines and treatments. The combination of all these elements and lifestyle choices facilitates the emergence of metabolic disorders (obesity, diabetes), which promote cardiovascular and kidney damage, and neurodegenerative diseases, explaining that the less well educated have shorter survival and spend more years of life in disability. After having demonstrated the impact of the educational level on health and longevity, the members of this inter-academic group propose specific educational actions at three levels: (1) teachers and health professionals, (2) parents, (3) the public, emphasizing that these crucial actions can only be carried out with the unfailing support of state and academic authorities.


Assuntos
COVID-19 , Envelhecimento Saudável , Humanos , Acontecimentos que Mudam a Vida , Pandemias , COVID-19/epidemiologia , Escolaridade , Educação em Saúde
2.
4.
Front Immunol ; 13: 844727, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529881

RESUMO

The immunopathological pulmonary mechanisms leading to Coronavirus Disease (COVID-19)-related death in adults remain poorly understood. Bronchoalveolar lavage (BAL) and peripheral blood sampling were performed in 74 steroid and non-steroid-treated intensive care unit (ICU) patients (23-75 years; 44 survivors). Peripheral effector SARS-CoV-2-specific T cells were detected in 34/58 cases, mainly directed against the S1 portion of the spike protein. The BAL lymphocytosis consisted of T cells, while the mean CD4/CD8 ratio was 1.80 in non-steroid- treated patients and 1.14 in steroid-treated patients. Moreover, strong BAL SARS-CoV-2 specific T-cell responses were detected in 4/4 surviving and 3/3 non-surviving patients. Serum IFN-γ and IL-6 levels were decreased in steroid-treated patients when compared to non-steroid treated patients. In the lung samples from 3 (1 non-ICU and 2 ICU) additional deceased cases, a lymphocytic memory CD4 T-cell angiopathy colocalizing with SARS-CoV-2 was also observed. Taken together, these data show that disease severity occurs despite strong antiviral CD4 T cell-specific responses migrating to the lung, which could suggest a pathogenic role for perivascular memory CD4 T cells upon fatal COVID-19 pneumonia.


Assuntos
COVID-19 , Pneumonia , Adulto , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos , Pulmão , SARS-CoV-2
5.
Front Immunol ; 13: 848571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464449

RESUMO

W614A-3S peptide is a modified 3S motif of the HIV-gp41 (mutation W614A). We previously detected the presence of natural neutralizing antibodies directed against W614A-3S peptide (NAbs) in long-term non-progressor HIV+ patients. Here, we compared the efficacy of W614A-3S peptide formulated in either squalene emulsion (SQE) or in aluminum hydroxide (Alum) in inducing broadly-NAbs (bNAbs). Rabbit and mouse models were used to screen the induction of bNAbs following 4 immunizations. SQE was more efficient than Alum formulation in inducing W614A-3S-specific bNAbs with up to 67%-93% of HIV strains neutralized. We then analyzed the quality of peptide-specific murine B cells by single-cell gene expression by quantitative reverse transcription-PCR and single-cell V(D)J sequencing. We found more frequent germinal center B cells in SQE than in Alum, albeit with a different gene expression profile. The V(D)J sequencing of W614A-3S-specific BCR showed significant differences in BCR sequences and validates the dichotomy between adjuvant formulations. All sixteen BCR sequences which were cloned were specific of peptide. Adjuvant formulations of W614A-3S-peptide-conjugated immunogen impact the quantity and quality of B cell immune responses at both the gene expression level and BCR sequence.


Assuntos
Anticorpos Neutralizantes , Infecções por HIV , Adjuvantes Imunológicos , Hidróxido de Alumínio , Animais , Anticorpos Amplamente Neutralizantes , Emulsões , Humanos , Camundongos , Peptídeos , Coelhos , Esqualeno , Vacinas Conjugadas , Vacinas de Subunidades Antigênicas
6.
C R Biol ; 345(3): 83-92, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36852598

RESUMO

In the 19th century, the applications of the scientific discoveries of Louis Pasteur to medicine had difficulty in imposing themselves within the French medical community and its National Academy. Among those concerning infectious diseases, their prevention by hygiene and their etiology by microbes are described here. Louis Pasteur found it difficult to convince and had to fight, to show through the surgical practice of asepsis and examples of infections induced in animal models (anthrax), the modes of transmission of germs and their pathogenicity.


Les applications des découvertes scientifiques de Louis Pasteur à la médecine ont eu du mal à s'imposer au XIX e siècle auprès de la communauté médicale française et de son Académie Nationale. Parmi celles qui concernent les maladies infectieuses, leur prévention par l'hygiène et leur étiologie par les microbes sont ici décrites. Louis Pasteur eut du mal à convaincre et dut combattre, pour montrer à travers la pratique chirurgicale de l'asepsie et des exemples d'infections induites dans des modèles animaux (anthrax), les modalités de transmission des germes et leur pathogénicité.


Assuntos
Academias e Institutos , Higiene , Animais
7.
Stem Cell Reports ; 16(8): 1847-1852, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34329597

RESUMO

Regenerative medicine has great potential. The pace of scientific advance is exciting and the medical opportunities for regeneration and repair may be transformative. However, concerns continue to grow, relating to problems caused both by unscrupulous private clinics offering unregulated therapies based on little or no evidence and by premature regulatory approval on the basis of insufficient scientific rationale and clinical evidence. An initiative by the InterAcademy Partnership convened experts worldwide to identify opportunities and challenges, with a focus on stem cells. This was designed to be inclusive and consensus outputs reflected the diversity of the global research population. Among issues addressed for supporting research and innovation while protecting patients were ethical assessment; pre-clinical and clinical research; regulatory authorization and medicines access; and engagement with patients, policy makers, and the public. The InterAcademy Partnership (IAP) identified options for action for sharing good practice and building collaboration within the scientific community and with other stakeholders worldwide.


Assuntos
Pesquisa Biomédica/métodos , Medicina Regenerativa/métodos , Projetos de Pesquisa , Células-Tronco/citologia , Animais , Pesquisa Biomédica/organização & administração , Pesquisa Biomédica/tendências , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Baseada em Transplante de Células e Tecidos/tendências , Humanos , Disseminação de Informação/métodos , Internacionalidade , Medicina Regenerativa/organização & administração , Medicina Regenerativa/tendências , Células-Tronco/metabolismo
8.
Bull Acad Natl Med ; 205(7): 694-702, 2021 Aug.
Artigo em Francês | MEDLINE | ID: mdl-34092797

RESUMO

The COVID-19 pandemic occurred in the context of a dramatic decline in support for biological and health research in France. An analysis of resources allocated to this sector shows that the credits in 2020 correspond to only 17.2 % of the total credits allocated to research, the lowest ratio inat least 15 years. Another weakness in the system of support for hospital research is the way funds from the health insurance system are allocated. To bring it into line with international best practices, the task of allocating these funds should be entrusted to a "Hospital Research Orientation Council", which should also be involved in the implementation of national research programming. Another article deals with the organization of research. Recommendations are also made to improve the functioning of the research system at the local level, particularly in university hospitals, and at the national level.

9.
Front Med (Lausanne) ; 8: 664179, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055838

RESUMO

At the beginning of 2021, anti-SARS-CoV-2 vaccination campaigns had been launched in almost 60 countries with more than 500 million doses having been distributed. In addition to the few vaccines already in use, many other candidates are in preclinical phases or experimental stages in humans. Despite the fact that the availability of anti-SARS-CoV-2 vaccine constitutes a major advance and appear to be the only way to control the pandemic, some investigation remains to be carried out, and this is notably concerning the impact on transmissibility, the duration of the conferred protection in the mid- and long term, the effectiveness against present and future viral mutants, or the ideal schedule that should be applied. In this paper, we review the circumstances that facilitated such a rapid development of anti-SARS-CoV-2 vaccines and summarize the different vaccine platforms under investigation as well as their present results and perspectives in different settings. We also discuss the indications of vaccination under special conditions, such as a history of previous COVID-19 infection or belonging to extreme age categories like children and elderly. Overall, this review highlights the multiple challenges to face if aiming to find a global solution to the pandemic through high vaccination coverage all over the world.

10.
PLoS Negl Trop Dis ; 15(3): e0009246, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33661894

RESUMO

One health (OH) approaches have increasingly been used in the last decade in the fight against zoonotic neglected tropical diseases (NTDs). However, descriptions of such collaborations between the human, animal and environmental health sectors are still limited for French-speaking tropical countries. The objective of the current survey was to explore the diversity of OH experiences applied to research, surveillance and control of NTDs by scientists from French-speaking countries, and discuss their constraints and benefits. Six zoonotic NTDs were targeted: echinococcoses, trypanosomiases, leishmaniases, rabies, Taenia solium cysticercosis and leptospiroses. Invitations to fill in an online questionnaire were sent to members of francophone networks on NTDs and other tropical diseases. Results from the questionnaire were discussed during an international workshop in October 2019. The vast majority (98%) of the 171 respondents considered OH approaches relevant although only 64% had implemented them. Among respondents with OH experience, 58% had encountered difficulties mainly related to a lack of knowledge, interest and support for OH approaches by funding agencies, policy-makers, communities and researchers. Silos between disciplines and health sectors were still strong at both scientific and operational levels. Benefits were reported by 94% of respondents with OH experience, including increased intellectual stimulation, stronger collaborations, higher impact and cost-efficiency of interventions. Recommendations for OH uptake included advocacy, capacity-building, dedicated funding, and higher communities' involvement. Improved research coordination by NTD networks, production of combined human-animal health NTD impact indicators, and transversal research projects on diagnostic and reservoirs were also considered essential.


Assuntos
Doenças Negligenciadas/prevenção & controle , Medicina Tropical , Zoonoses/prevenção & controle , Animais , Pesquisa Biomédica , Humanos , Inquéritos e Questionários
11.
Mol Psychiatry ; 26(9): 5297-5306, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33456051

RESUMO

Accumulating evidence majorly implicates immune dysfunction in the etiology of psychotic disorders. In particular, altered numbers and functions of natural killer (NK) cells have been described in psychosis, but interpretation has often been confounded by a number of biases, including treatment. Eighty-one first-episode psychosis (FEP) patients who subsequently received a diagnosis of either schizophrenia (SZ; n = 30) or bipolar disorder (BP; n = 31) over a five-year follow-up period were investigated for their NK cell phenotype and compared to 61 healthy controls (HCs). We found a similar proportion of CD3-CD56+ NK cells in FEP patients and HCs. The frequency of NK cells expressing the late cell activation marker HLA-DR was significantly increased in FEP patients compared to HCs, especially in patients with BP (p < 0.0001) and, to a lesser degree, in patients with SZ (p = 0.0128). Interestingly, the expression of the activating NKG2C receptor, known to be associated with infections, was higher in patients with SZ and BP than in HCs (p < 0.0001) and correlated with HLA-DR expression, altogether defining adaptive NK cells. In terms of NK cell function, we observed a suppressed capacity of SZ-derived NK cells to mount cytotoxic responses in the presence of target cells, while NK cells from patients with BP show an inability to produce IFN-γ, a cytokine pivotal to NK function. This study strongly suggests major dysfunction of NK cells in FEP with functioning impairment correlated with psychotic, manic, and depressive symptoms in subsequently diagnosed patients with SZ and BP.


Assuntos
Transtorno Bipolar , Transtornos Psicóticos , Esquizofrenia , Humanos , Imunidade Inata , Células Matadoras Naturais
12.
Front Immunol ; 11: 1662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32719687

RESUMO

An unprecedented outbreak of pneumonia caused by a novel coronavirus (CoV), subsequently termed COVID-19 by the World Health Organization, emerged in Wuhan City (China) in December 2019. Despite rigorous containment and quarantine efforts, the incidence of COVID-19 continues to expand, causing explosive outbreaks in more than 160 countries with waves of morbidity and fatality, leading to significant public health problems. In the past 20 years, two additional epidemics caused by CoVs have occurred: severe acute respiratory syndrome-CoV, which has caused a large-scale epidemic in China and 24 other countries; and respiratory syndrome-CoV of the Middle East in Saudi Arabia, which continues to cause sporadic cases. All of these viruses affect the lower respiratory tract and manifest as pneumonia in humans, but the novel SARS-Cov-2 appears to be more contagious and has spread more rapidly worldwide. This mini-review focuses on the cellular immune response to COVID-19 in human subjects, compared to other clinically relevant coronaviruses to evaluate its role in the control of infection and pathogenesis and accelerate the development of a preventive vaccine or immune therapies.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus , Epidemias , Imunidade Celular , Imunoterapia , Pandemias , Pneumonia Viral , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , SARS-CoV-2
13.
Med Sci (Paris) ; 36(6-7): 642-646, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32530418

RESUMO

TITLE: Épidémies: Leçons d'Histoire. ABSTRACT: Jusqu'au milieu du XVIIIe siècle, l'espérance de vie était de 25 ans dans les pays d'Europe, proche alors de celle de la préhistoire. À cette époque, nos ancêtres succombaient, pour la plupart, à une infection bactérienne ou virale, quand la mort n'était pas le résultat d'un épisode critique, comme la guerre ou la famine. Un seul microbe suffisait à terrasser de nombreuses victimes. L'épidémie de SARS-CoV-2 est là pour nous rappeler que ce risque est désormais à nouveau d'actualité. Si son origine zoonotique par la chauve-souris est probable, la contamination interhumaine montre son adaptation rapide à l'homme et permet d'évoquer ainsi la transmission des épidémies, qu'elle soit ou non liée à des vecteurs, ces derniers pouvant représenter dans d'autres occasions un des maillons de la chaîne.


Assuntos
Infecções Bacterianas/epidemiologia , Epidemias/história , Viroses/epidemiologia , Adulto , Animais , Infecções Bacterianas/história , Betacoronavirus/fisiologia , COVID-19 , Bovinos , Quirópteros/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/história , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/epidemiologia , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Cães , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , Humanos , Expectativa de Vida/história , Expectativa de Vida/tendências , Longevidade/fisiologia , Pandemias , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Ovinos/microbiologia , Ovinos/virologia , Suínos/microbiologia , Suínos/virologia , Viroses/história , Zoonoses/epidemiologia , Zoonoses/virologia
14.
NPJ Vaccines ; 4: 25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231551

RESUMO

VAC-3S is a therapeutic vaccine comprising a highly conserved HIV-gp41 motif coupled with the CRM197 carrier protein. High levels of anti-3S antibodies (Abs) have been associated with improved protection of CD4+ T-cell survival. A previous phase 1 study demonstrated the safety of VAC-3S. This multicentre, randomised, double-blind, placebo-controlled phase 2 clinical trial enroled between January 2014 and March 2015 HIV-1-infected patients under ART with plasma HIV RNA levels below 50 copies/mL and CD4 counts between 200 and 500 cells/µL. Participants were immunised with 16, 32, or 64 µg of VAC-3S, and compared to placebo. The primary outcome was immunogenicity assessed by changes from baseline of anti-3S Abs levels at week 12. Secondary outcomes included adverse events and the course of plasma HIV RNA level, CD4 count, CD4/CD8 ratio, inflammation and immune checkpoints from week 0 to week 48. Vaccination was well tolerated with no serious adverse events and induced a significant increase in anti-3S Ab response in vaccinated patients (p < 0.0001), compared to placebo. In high responders, the robust increased of CD4 count was associated with a significant and sustained reduction of PD-1 expression on CD4+ T cells through week 48 (variance p = 0.0017). PD-1 expression was correlated with level of anti-3S Abs (p = 0.0092, r = -0.68) and expression of NKp44L (p < 0.0001; r = 0.54) in CD4+ T cells. Our findings regarding the increase of non-exhausted CD4+ T cells have potentially important application in personalised HIV vaccination for HIV-infected patients with high level of PD-1 to improve their T-cell immune function.

15.
Mol Autism ; 10: 22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31123562

RESUMO

Background: Autism spectrum disorders (ASD) are characterized by abnormal neurodevelopment, genetic, and environmental risk factors, as well as immune dysfunctions. Several lines of evidence suggest alterations in innate immune responses in children with ASD. To address this question in adults with high-functioning ASD (hf-ASD), we sought to investigate the role of natural killer (NK) cells in the persistence of ASD. Methods: NK cells from 35 adults with hf-ASD were compared to that of 35 healthy controls (HC), selected for the absence of any immune dysfunctions, at different time-points, and over a 2-year follow-up period for four patients. The phenotype and polyfunctional capacities of NK cells were explored according to infectious stigma and clinical parameters (IQ, social, and communication scores). Results: As compared to HC, NK cells from patients with hf-ASD showed a high level of cell activation (p < 0.0001), spontaneous degranulation (p < 0.0001), and interferon-gamma production (p = 0.0004), whereas they were exhausted after in vitro stimulations (p = 0.0006). These data yielded a specific HLA-DR+KIR2DL1+NKG2C+ NK-cell signature. Significant overexpression of NKG2C in hf-ASD patients (p = 0.0005), indicative of viral infections, was inversely correlated with the NKp46 receptor level (r = - 0.67; p < 0.0001), regardless of the IgG status of tested pathogens. Multivariate linear regression analysis also revealed that expression of the late-activating HLA-DR marker was both associated with structural language (r = 0.48; p = 0.007) and social awareness (r = 0.60; p = 0.0007) scores in adult patients with hf-ASD, while KIR2DL1 expression correlated with IQ scores (p = 0.0083). Conclusions: This study demonstrates that adults with hf-ASD have specific NK-cell profile. Presence of NKG2C overexpression together with high-level activation of NK cells suggest an association with underlying pathogens, a hypothesis warranting further exploration in future studies.


Assuntos
Transtorno do Espectro Autista/imunologia , Infecções/imunologia , Células Matadoras Naturais/imunologia , Adolescente , Adulto , Análise por Conglomerados , Comunicação , Feminino , Humanos , Testes de Inteligência , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores KIR2DL1/genética , Receptores KIR2DL1/metabolismo , Comportamento Social , Adulto Jovem
16.
J Immunol Res ; 2019: 9804584, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019982

RESUMO

The design of immunogens susceptible to elicit potent and broadly neutralizing antibodies against the human immunodeficiency virus type 1 (HIV-1) remains a veritable challenge in the course of vaccine development. Viral envelope proteins adopt different conformational states during the entry process, allowing the presentation of transient neutralizing epitopes. We focused on the highly conserved 3S motif of gp41, which is exposed to the surface envelope in its trimeric prefusion state. Vaccination with a W614A-modified 3S peptide induces in animals neutralizing anti-HIV-1 antibodies among which we selected clone F8. We used F8 as bait to select for W614A-3S phage-peptide mimics. Binding and molecular docking studies revealed that F8 interacts similarly with W614A-3S and a Mim_F8-1 mimotope, despite their lack of sequence homology, suggesting structural mimicry. Finally, vaccination of mice with the purified Mim_F8-1 phage elicited HIV-1-neutralizing antibodies that bound to the cognate W614A-3S motif. Collectively, our findings provide new insights into the molecular design of immunogens to elicit antibodies with neutralizing properties.


Assuntos
Anticorpos Neutralizantes/imunologia , Mapeamento de Epitopos/métodos , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Animais , Anticorpos Monoclonais/imunologia , Bacteriófagos/imunologia , HIV-1 , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Simulação de Acoplamento Molecular , Testes de Neutralização , Peptídeos/administração & dosagem , Peptídeos/imunologia , Ligação Proteica/efeitos dos fármacos
17.
EBioMedicine ; 40: 605-613, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30711514

RESUMO

BACKGROUND: Lassa virus (LASV) is the etiologic agent of an acute hemorrhagic fever endemic in West Africa. Natural killer (NK) cells control viral infections in part through the interaction between killer cell immunoglobulin-like receptors (KIRs) and their ligands. LASV infection is associated with defective immune responses, including inhibition of NK cell activity in the presence of MHC-class 1+-infected target cells. METHODS: We compared individual KIR and HLA-class 1 genotypes of 68 healthy volunteers to 51 patients infected with LASV in Sierra Leone, including 37 survivors and 14 fatalities. Next, potential HLA-C1, HLA-C2, and HLA-Bw4 binding epitopes were in silico screened among LASV nucleoprotein (NP) and envelope glycoprotein (GP). Selected 10-mer peptides were then tested in peptide-HLA stabilization, KIR binding and polyfunction assays. FINDINGS: LASV-infected patients were similar to healthy controls, except for the inhibitory KIR2DL2 gene. We found a specific increase in the HLA-C1:KIR2DL2 interaction in fatalities (10/11) as compared to survivors (12/19) and controls (19/29). We also identified that strong of NP and GP viral epitopes was only observed with HLA-C molecules, and associated with strong inhibition of degranulation in the presence of KIR2DL+ NK cells. This inhibitory effect significantly increased in the presence of the vGP420 variant, detected in 28.1% of LASV sequences. INTERPRETATION: Our finding suggests that presentation of specific LASV epitopes by HLA-C alleles to the inhibitory KIR2DL2 receptor on NK cells could potentially prevent the killing of infected cells and provides insights into the mechanisms by which LASV can escape NK-cell-mediated immune pressure.


Assuntos
Epitopos/imunologia , Antígenos HLA-C/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Febre Lassa/imunologia , Febre Lassa/metabolismo , Vírus Lassa/imunologia , Receptores KIR2DL2/metabolismo , Antígenos Virais/imunologia , Linhagem Celular , Citotoxicidade Imunológica , Mapeamento de Epitopos/métodos , Genótipo , Antígenos HLA-C/genética , Humanos , Tolerância Imunológica , Imunomodulação , Imunofenotipagem , Febre Lassa/genética , Febre Lassa/virologia , Ligação Proteica , Receptores KIR2DL2/genética
18.
ACS Appl Mater Interfaces ; 11(10): 9824-9831, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30758939

RESUMO

We describe the preparation and characterization of synthetic antibodies based on molecularly imprinted polymer nanoparticles (MIP-NPs) for the recognition and binding of the highly conserved and specific peptide motif SWSNKS (3S), an epitope of the envelope glycoprotein 41 (gp41) of human immunodeficiency virus type 1 (HIV-1). This motif is implicated in the decline of CD4+ T cells and leads to the deterioration of the immune system during HIV infection. Therefore, the development of MIP-NPs that can target and block the 3S peptide to prevent subsequent cascade interactions directed toward the killing of CD4+ T cells is of prime importance. Because most antibodies recognize their protein antigen via a conformational or structured epitope (as opposed to a linear epitope commonly used for molecular imprinting), we employed protein molecular modeling to design our template epitope so that it mimics the three-dimensional structure fold of 3S in gp41. The resulting template peptide corresponds to a cyclic structure composed of CGSWSNKSC, with the 3S motif well orientated for imprinting. MIP-NPs with a size of 65 nm were obtained by solid-phase synthesis and were water-soluble. They were prepared by a judicious combination of multiple functional monomers affording hydrogen bonding, ionic, π-π, and hydrophobic interactions, conferring high affinity and selectivity toward both the cyclic peptide and the whole gp41 protein. These results suggest that our MIPs could potentially be used for blocking the function of the 3S motif on the virus.


Assuntos
Anticorpos/administração & dosagem , Infecções por HIV/tratamento farmacológico , Impressão Molecular , Nanopartículas/administração & dosagem , Peptídeos/administração & dosagem , Motivos de Aminoácidos/imunologia , Anticorpos/imunologia , Formação de Anticorpos/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Epitopos/efeitos dos fármacos , Epitopos/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Ligação de Hidrogênio , Nanopartículas/química , Peptídeos/síntese química , Peptídeos/química , Polímeros/administração & dosagem , Polímeros/síntese química , Polímeros/química , Conformação Proteica/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/virologia
19.
AIDS ; 33(1): 23-32, 2019 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-30325780

RESUMO

OBJECTIVE: HIV-1 and HIV-2 differ notably in their epidemiology, with worldwide HIV-1 spread and HIV-2 mainly confined to West Africa. Natural killer (NK) cells are critical antiviral effectors of the immune system; however, limited information is available about these innate effector cells during HIV-2 infection. METHOD: In this study, 24 untreated HIV-2-infected patients were analyzed and compared with 21 long-term nonprogressor and 10 controller HIV-1 patients, and healthy donors. Extensive phenotype and functional NK-cell characteristics, as well as ligands of activating NK receptors involved in NK lysis were determined by flow cytometry. RESULTS: We report in HIV-2 patients a very significant reduced expression of the activating NKp30 receptor (P < 0.0001) on NK cells, much higher than observed in HIV-1 patients. The impaired expression of NKp30 is correlated negatively with HLA-DR (r = -0.5970; P = 0.0002), and positively with both NKG2A (r = 0.5324; P < 0.0001) and Siglec-7 (r = 0.5621; P = 0.0004). HIV-2 patients with NKp30 NK cells displayed overproduction of IFN-γ (P < 0.0001) associated with impaired cytolytic function when tested against target cells expressing surface B7-H6. This cellular ligand of NKp30 is strongly detectable as a surface molecule on CD4 T cells infected by HIV-2. CONCLUSION: Altogether, our data suggested that the defective expression of NKp30 may be induced by the chronic engagement of this receptor by B7-H6 expressed on HIV-2-infected target cells. This represents a novel mechanism by which the chronic ligand exposure by the viral environment may subvert NK-cell-mediated function to establish persistent HIV-2 infection.


Assuntos
Antígenos B7/metabolismo , Regulação para Baixo , Infecções por HIV/virologia , HIV-2/patogenicidade , Evasão da Resposta Imune , Células Matadoras Naturais/imunologia , Receptor 3 Desencadeador da Citotoxicidade Natural/biossíntese , Adulto , Feminino , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Hum Immunol ; 79(7): 571-577, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29709555

RESUMO

The precise diagnosis of an immunodeficiency is sometimes difficult to assess, especially due to the large spectrum of phenotypic variation reported among patients. Common variable immunodeficiency disorders (CVID) do not have, for a large part, an identified genetic cause. The identification of a causal genetic mutation is important to confirm, or in some cases correct, the diagnosis. We screened >150 male patients with hypogammaglobulinemia for mutations in three genes involved in pediatric X-linked primary immunoglobulin deficiency: CD40LG, SH2D1A and BTK. The SH2D1A screening allowed to reclassify two individuals with an initial CVID presentation as XLP after mutations identification. All these mutations were associated with a lack of protein expression. In addition, 4 patients with a primary diagnosis of CVID and one with a primary IgG subclass deficiency were requalified as XLA after identifying BTK mutations. Interestingly, two out of these 5 patients carried a damaging coding BTK mutation associated with a lower, but detectable, BTK expression in monocytes, suggesting that a dysfunctional protein explains the disease phenotype in these patients. In conclusion, our results advocate to include SH2D1A and BTK in newly developed targeted NGS genetic testing, to contribute to providing the most appropriate medical treatment and genetic counselling.


Assuntos
Agamaglobulinemia/diagnóstico , Monócitos/fisiologia , Proteínas Tirosina Quinases/genética , Proteínas Recombinantes de Fusão/genética , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária/genética , Tirosina Quinase da Agamaglobulinemia , Biomarcadores/metabolismo , Pré-Escolar , Análise Mutacional de DNA , Aconselhamento Genético , Testes Genéticos , Humanos , Lactente , Masculino , Mutação/genética , Fenótipo
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