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1.
Lancet Infect Dis ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38513684

RESUMO

BACKGROUND: A human hookworm vaccine is being developed to protect children against iron deficiency and anaemia associated with chronic infection with hookworms. Necator americanus aspartic protease-1 (Na-APR-1) and N americanus glutathione S-transferase-1 (Na-GST-1) are components of the blood digestion pathway critical to hookworm survival in the host. Recombinant Na-GST-1 and catalytically inactive Na-APR-1 (Na-APR-1[M74]) adsorbed to Alhydrogel were safe and immunogenic when delivered separately or co-administered to adults in phase 1 trials in non-endemic and endemic areas. We aimed to investigate the safety and immunogenicity of these antigens in healthy children in a hookworm-endemic area. METHODS: This was a randomised, controlled, observer-blind, phase 1, dose-escalation trial, conducted in a clinical research centre, in 60 children aged six to ten years in Lambaréné, a hookworm-endemic region of Gabon. Healthy children (determined by clinical examination and safety laboratory testing) were randomised 4:1 to receive co-administered Na-GST-1 on Alhydrogel plus Na-APR-1(M74) on Alhydrogel and glucopyranosyl lipid A in aqueous formulation (GLA-AF), or co-administered ENGERIX-B hepatitis B vaccine (HBV) and saline placebo, injected into the deltoid of each arm. Allocation to vaccine groups was observer-masked. In each vaccine group, children were randomised 1:1 to receive intramuscular injections into each deltoid on two vaccine schedules, one at months 0, 2, and 4 or at months 0, 2, and 6. 10 µg, 30 µg, and 100 µg of each antigen were administered in the first, second, and third cohorts, respectively. The intention-to-treat population was used for safety analyses; while for immunogenicity analyses, the per-protocol population was used (children who received all scheduled vaccinations). The primary outcome was to evaluate the vaccines' safety and reactogenicity in healthy children aged between six and ten years. The secondary outcome was to measure antigen-specific serum IgG antibody levels at pre-vaccination and post-vaccination timepoints by qualified ELISAs. The trial is registered with ClinicalTrials.gov, NCT02839161, and is completed. FINDINGS: Between Jan 23 and Oct 3, 2017, 137 children were screened, of whom 76 were eligible for this trial. 60 children were recruited, and allocated to either 10 µg of the co-administered antigens (n=8 for each injection schedule), 30 µg (n=8 for each schedule), 100 µg (n=8 for each schedule), or HBV and placebo (n=6 for each schedule) in three sequential cohorts. Co-administration of the vaccines was well tolerated; the most frequent solicited adverse events were mild-to-moderate injection-site pain, observed in up to 12 (75%) of 16 participants per vaccine group, and mild headache (12 [25%] of 48) and fever (11 [23%] of 48). No vaccine-related serious adverse events were observed. Significant anti-Na-APR-1(M74) and anti-Na-GST-1 IgG levels were induced in a dose-dependent manner, with peaks seen 14 days after the third vaccinations, regardless of dose (for Na-APR-1[M74], geometric mean levels [GML]=2295·97 arbitrary units [AU] and 726·89 AU, while for Na-GST-1, GMLs=331·2 AU and 21·4 AU for the month 0, 2, and 6 and month 0, 2, and 4 schedules, respectively). The month 0, 2, and 6 schedule induced significantly higher IgG responses to both antigens (p=0·01 and p=0·04 for Na-APR-1[M74] and Na-GST-1, respectively). INTERPRETATION: Co-administration of recombinant Na-APR-1(M74) and Na-GST-1 to school-aged Gabonese children was well tolerated and induced significant IgG responses. These results justify further evaluation of this antigen combination in proof-of-concept controlled-infection and efficacy studies in hookworm-endemic areas. FUNDING: European Union Seventh Framework Programme.

2.
Antibiotics (Basel) ; 12(4)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37107088

RESUMO

To combat infection by microorganisms host organisms possess a primary arsenal via the innate immune system. Among them are defense peptides with the ability to target a wide range of pathogenic organisms, including bacteria, viruses, parasites, and fungi. Here, we present the development of a novel machine learning model capable of predicting the activity of antimicrobial peptides (AMPs), CalcAMP. AMPs, in particular short ones (<35 amino acids), can become an effective solution to face the multi-drug resistance issue arising worldwide. Whereas finding potent AMPs through classical wet-lab techniques is still a long and expensive process, a machine learning model can be useful to help researchers to rapidly identify whether peptides present potential or not. Our prediction model is based on a new data set constructed from the available public data on AMPs and experimental antimicrobial activities. CalcAMP can predict activity against both Gram-positive and Gram-negative bacteria. Different features either concerning general physicochemical properties or sequence composition have been assessed to retrieve higher prediction accuracy. CalcAMP can be used as an promising prediction asset to identify short AMPs among given peptide sequences.

3.
PLoS Negl Trop Dis ; 15(10): e0009732, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34597297

RESUMO

Two hookworm vaccine candidates, Na-GST-1 and Na-APR-1, formulated with Glucopyranosyl Lipid A (GLA-AF) adjuvant, have been shown to be safe, well tolerated, and to induce antibody responses in a Phase 1 clinical trial (Clinicaltrials.gov NCT02126462) conducted in Gabon. Here, we characterized T cell responses in 24 Gabonese volunteers randomized to get vaccinated three times with Na-GST-1 and Na-APR-1 at doses of 30µg (n = 8) or 100µg (n = 10) and as control Hepatitis B (n = 6). Blood was collected pre- and post-vaccination on days 0, 28, and 180 as well as 2-weeks after each vaccine dose on days 14, 42, and 194 for PBMCs isolation. PBMCs were stimulated with recombinant Na-GST-1 or Na-APR-1, before (days 0, 28 and 180) and two weeks after (days 14, 42 and 194) each vaccination and used to characterize T cell responses by flow and mass cytometry. A significant increase in Na-GST-1 -specific CD4+ T cells producing IL-2 and TNF, correlated with specific IgG antibody levels, after the third vaccination (day 194) was observed. In contrast, no increase in Na-APR-1 specific T cell responses were induced by the vaccine. Mass cytometry revealed that, Na-GST-1 cytokine producing CD4+ T cells were CD161+ memory cells expressing CTLA-4 and CD40-L. Blocking CTLA-4 enhanced the cytokine response to Na-GST-1. In Gabonese volunteers, hookworm vaccine candidate, Na-GST-1, induces detectable CD4+ T cell responses that correlate with specific antibody levels. As these CD4+ T cells express CTLA-4, and blocking this inhibitory molecules resulted in enhanced cytokine production, the question arises whether this pathway can be targeted to enhance vaccine immunogenicity.


Assuntos
Ancylostomatoidea/imunologia , Antígenos de Helmintos/administração & dosagem , Infecções por Uncinaria/imunologia , Infecções por Uncinaria/prevenção & controle , Linfócitos T/imunologia , Vacinas/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Adulto , Ancylostomatoidea/genética , Animais , Anticorpos Anti-Helmínticos/imunologia , Formação de Anticorpos , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Feminino , Gabão , Infecções por Uncinaria/parasitologia , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Vacinação , Vacinas/genética , Vacinas/imunologia , Adulto Jovem
5.
Lancet Infect Dis ; 21(2): 275-285, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32926834

RESUMO

BACKGROUND: Hookworms cause substantial morbidity in children and women of reproductive age. The control strategy of mass drug administration is suboptimal, hence the need for a vaccine. Necator americanus aspartic protease-1 (Na-APR-1) and N americanus glutathione S-transferase-1 (Na-GST-1) are involved in the digestion and detoxification of haemoglobin in the hookworm digestive tract. In animal models, vaccination against these antigens resulted in protection from challenge infection. Both vaccine candidates were shown to be safe and well tolerated when administered separately to healthy adults. We assessed the safety and immunogenicity of co-administered Na-GST-1 and Na-APR-1 (M74) vaccines in healthy Gabonese adults. METHODS: This randomised, controlled, double-blind, phase 1, dose-escalation trial was done at the Centre de Recherches Médicales de Lambaréné, in a region of Gabon where N americanus and other helminths are prevalent. Healthy adults aged 18-50 years and living in Lambaréné or the surrounding areas were recruited to the study. Participants were enrolled consecutively into two dose cohorts (30 µg or 100 µg of the experimental vaccines) and randomly assigned in blocks (block size four) to receive three doses of either co-administered Na-GST-1 plus Na-APR-1 (M74; 30 µg or 100 µg of each), adjuvanted with Alhydrogel (aluminium hydroxide gel suspension) together with an aqueous formulation of glucopyranosyl lipid A, or hepatitis B vaccine plus saline (control group). Vaccines were administered intramuscularly on days 0, 28, and 180. The primary endpoint was safety, with immunogenicity a secondary endpoint. The intention-to-treat population was used for safety analyses, whereas for immunogenicity analyses, the per-protocol population was used (participants who received all scheduled vaccinations). Control vaccine recipients for both dose cohorts were combined for the analyses. The trial is registered with ClinicalTrials.gov, NCT02126462. FINDINGS: Between Oct 27, 2014, and Jan 31, 2015, 56 individuals were screened for eligibility, of whom 32 were enrolled and randomly assigned to one of the three study groups (12 each in the 30 µg and 100 µg experimental vaccine groups and eight in the control group). Both study vaccines were well tolerated in both dose groups. The most common adverse events were mild-to-moderate injection-site pain, headache, myalgia, and nausea. No severe or serious adverse events related to the vaccines were recorded. 52 unsolicited vaccine-related adverse events occurred during the study, but there was no difference in frequency between vaccine groups. IgG antibodies were induced to each of the vaccine antigens, with mean IgG levels increasing after each vaccination. Vaccination with 100 µg of each vaccine antigen consistently induced IgG seroconversion (IgG levels above the reactivity threshold). Peak IgG responses were observed 2 weeks after the third vaccine dose for both antigens, with all participants who received the 100 µg doses seroconverting at that timepoint. IgG levels steadily declined until the final study visit 6 months after the third vaccination, although they remained significantly higher than baseline in the 100 µg dose group. INTERPRETATION: Vaccination with recombinant Na-GST-1 and Na-APR-1 (M74) in healthy adults living in N americanus-endemic areas of Gabon was safe and induced IgG to each antigen. To our knowledge, this study is the first to report results of Na-APR-1 (M74) co-administered with Alhydrogel in participants from an N americanus-endemic area. Further clinical development of these vaccines should involve efficacy studies. FUNDING: European Union Seventh Framework Programme.


Assuntos
Infecções por Uncinaria/prevenção & controle , Necator americanus/imunologia , Vacinas/imunologia , Adulto , Animais , Anticorpos Anti-Helmínticos/sangue , Relação Dose-Resposta Imunológica , Método Duplo-Cego , Feminino , Gabão/epidemiologia , Infecções por Uncinaria/epidemiologia , Humanos , Imunoglobulina G/sangue , Masculino , Vacinas/administração & dosagem , Adulto Jovem
6.
BMJ Glob Health ; 4(5): e001559, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31646008

RESUMO

Global Health has not featured as prominently in the European Union (EU) research agenda in recent years as it did in the first decade of the new millennium, and participation of low-income and middle-income countries (LMICs) in EU health research has declined substantially. The Horizon Europe Research and Innovation Framework adopted by the European Parliament in April 2019 for the period 2021-2027 will serve as an important funding instrument for health research, yet the proposed health research budget to be finalised towards the end of 2019 was reduced from 10% in the current framework, Horizon 2020, to 8% in Horizon Europe. Our analysis takes the evolvement of Horizon Europe from the initial framework of June 2018 to the framework agreed on in April 2019 into account. It shows that despite some improvements in terms of Global Health and reference to the Sustainable Development Goals, European industrial competitiveness continues to play a paramount role, with Global Health research needs and relevant health research for LMICs being only partially addressed. We argue that the globally interconnected nature of health and the transdisciplinary nature of health research need to be fully taken into account and acted on in the new European Research and Innovation Framework. A facilitated global research collaboration through Horizon Europe could ensure that Global Health innovations and solutions benefit all parts of the world including EU countries.

7.
Int J Antimicrob Agents ; 54(5): 610-618, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31356860

RESUMO

Skin bacterial colonization/infection is a frequent cause of morbidity in patients with chronic wounds and allergic/inflammatory skin diseases. This study aimed to develop a novel approach to eradicate meticillin-resistant Staphylococcus aureus (MRSA) from human skin. To achieve this, the stability and antibacterial activity of the novel LL-37-derived peptide P10 in four ointments was compared. Results indicate that P10 is chemically stable and antibacterial in hypromellose gel and Softisan-containing cream, but not in Cetomacrogol cream (with or without Vaseline), at 4 °C for 16 months. Reduction in MRSA counts on Leiden human epidermal models (LEMs) by P10 in hypromellose gel was greater than that of the peptide in Cetomacrogol cream or phosphate buffered saline. P10 did not show adverse effects on LEMs irrespective of the ointment used, while Cetomacrogol with Vaseline and Softisan cream, but not hypromellose gel or Cetomacrogol cream, destroyed MRSA-colonized LEMs. Taking all this into account, P10 in hypromellose gel dose-dependently reduced MRSA colonizing the stratum corneum of the epidermis as well as biofilms of this bacterial strain on LEMs. Moreover, P10 dose-dependently reduced MRSA counts on ex-vivo human skin, with P10 in hypromellose gel being more effective than P10 in Cetomacrogol and Softisan creams. P10 in hypromellose gel is a strong candidate for eradication of MRSA from human skin.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pomadas/farmacologia , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Administração Tópica , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cetomacrogol/farmacologia , Portadores de Fármacos/farmacologia , Humanos , Derivados da Hipromelose/farmacologia , Lipídeos/farmacologia , Testes de Sensibilidade Microbiana , Vaselina/farmacologia , Pele/microbiologia , Catelicidinas
8.
Lancet ; 384(9958): 1942-51, 2014 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25103176

RESUMO

BACKGROUND: Standard first-line antiretroviral therapy for HIV-1 infection includes two nucleoside or nucleotide reverse transcriptase inhibitors (NtRTIs), but these drugs have limitations. We assessed the 96 week efficacy and safety of an NtRTI-sparing regimen. METHODS: Between August, 2010, and September, 2011, we enrolled treatment-naive adults into this randomised, open-label, non-inferiority trial in treatment-naive adults in 15 European countries. The composite primary outcome was change to randomised treatment before week 32 because of insufficient virological response, no virological response by week 32, HIV-1 RNA concentration 50 copies per mL or higher at any time after week 32; death from any cause; any new or recurrent AIDS event; or any serious non-AIDS event. Patients were randomised in a 1:1 ratio to receive oral treatment with 400 mg raltegravir twice daily plus 800 mg darunavir and 100 mg ritonavir once daily (NtRTI-sparing regimen) or tenofovir-emtricitabine in a 245 mg and 200 mg fixed-dose combination once daily, plus 800 mg darunavir and 100 mg ritonavir once daily (standard regimen). This trial was registered with ClinicalTrials.gov, number NCT01066962. FINDINGS: Of 805 patients enrolled, 401 received the NtRTI-sparing regimen and 404 the standard regimen, with median follow-up of 123 weeks (IQR 112-133). Treatment failure was seen in 77 (19%) in the NtRTI-sparing group and 61 (15%) in the standard group. Kaplan-Meier estimated proportions of treatment failure by week 96 were 17·8% and 13·8%, respectively (difference 4·0%, 95% CI -0·8 to 8·8). The frequency of serious or treatment-modifying adverse events were similar (10·2 vs 8·3 per 100 person-years and 3·9 vs 4·2 per 100 person-years, respectively). INTERPRETATION: Our NtRTI-sparing regimen was non-inferior to standard treatment and represents a treatment option for patients with CD4 cell counts higher than 200 cells per µL. FUNDING: European Union Sixth Framework Programme, Inserm-ANRS, Gilead Sciences, Janssen Pharmaceuticals, Merck Laboratories.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Adenina/análogos & derivados , Adenina/uso terapêutico , Adulto , Contagem de Linfócito CD4 , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Darunavir , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Farmacorresistência Viral , Quimioterapia Combinada , Emtricitabina , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Organofosfonatos/uso terapêutico , Pirrolidinonas/uso terapêutico , Raltegravir Potássico , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Tenofovir , Resultado do Tratamento
9.
AIDS ; 17(7): 987-99, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12700448

RESUMO

OBJECTIVE: To compare one protease inhibitor (PI)-based and two PI-sparing antiretroviral therapy regimens. METHODS: International, open label, randomized study of antiretroviral drug-naive patients, with CD4 lymphocyte counts >/= 200 x 106 cells/l and plasma HIV-1 RNA levels > 500 copies/ml. Treatment assignment to stavudine and didanosine plus indinavir or nevirapine or lamivudine. Primary study endpoint was the percentage of patients with plasma HIV-1 RNA levels < 500 copies/ml after 48 weeks in the intention-to-treat analysis (ITT). RESULTS: In total, 298 patients were enrolled. After 48 weeks, the percentage of patients in the indinavir, nevirapine and lamivudine arms with HIV-1 RNA < 500 copies/ml was 57.0%, 58.4% and 58.7%, respectively, in an ITT analysis. After 96 weeks of follow-up, these percentages were 50.0%, 59.6% and 45.0%, respectively. The percentage of patients with HIV-1 RNA < 50 copies/ml was significantly less for those allocated to lamivudine in an on-treatment analysis after 48 and 96 weeks of follow-up. Patients in the nevirapine arm experienced a smaller increase in the absolute number of CD4 T lymphocytes. There were no significant differences in the incidence of serious adverse events. CONCLUSIONS: A comparable virological response can be achieved with first-line PI-base and PI-sparing regimens. The triple nucleoside regimen utilized may be less likely to result in viral suppression to < 50 copies/ml, while the nevirapine-based regimen is associated with a lower increase in CD4 T lymphocytes.


Assuntos
Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1 , Indinavir/uso terapêutico , Lamivudina/uso terapêutico , Nevirapina/uso terapêutico , Adolescente , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/sangue , Inibidores da Protease de HIV/efeitos adversos , Humanos , Indinavir/efeitos adversos , Lamivudina/efeitos adversos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Nevirapina/efeitos adversos , Resultado do Tratamento
10.
J Infect Dis ; 186(8): 1092-7, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12355359

RESUMO

Effective highly active antiretroviral therapy (HAART) for human immunodeficiency virus type 1 is associated with virus suppression and immune reconstitution. However, in some patients, this reconstitution is partial or incomplete because CD4(+) cell counts do not increase significantly. This may be due to damage in the microenvironment of lymphoid tissues (LTs), where CD4(+) T cells reside. To test this hypothesis, LT samples were obtained from 23 patients enrolled in a prospective trial that compared 3 different HAART regimens. Analysis of LT architecture and CD4(+) T cells populations revealed abnormalities in 100% of the LT samples, especially in the follicles, with 43% showing absence, 14% showing regression, and 43% showing hyperplasia. CD4(+) T cell populations were abnormal in 16 (89%) of 18 tissue samples, with 7 (39%) of 18 decreased by >50% of normal levels. These data are consistent with the hypothesis that persistent abnormalities in the microenvironment can influence immune reconstitution and document persistent LT abnormalities with HAART not detected by measures of peripheral CD4(+) T cell count.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Tecido Linfoide/imunologia , Tecido Linfoide/patologia , Adulto , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Estudos de Coortes , Feminino , HIV/imunologia , HIV/fisiologia , Infecções por HIV/imunologia , Humanos , Tecido Linfoide/efeitos dos fármacos , Masculino , RNA Viral/sangue , Carga Viral
11.
Ethiop Med J ; 40 Suppl 1: 51-75, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12802831

RESUMO

Slightly more than a decade after the discovery of HIV as the causative agent of AIDS, effective therapies against this virus have become available. Because of a large degree of cross-resistance among antiretroviral agents in the same class (nRTIs, NNRTIs, or PIs), once a therapy has failed virologically, future therapeutic options with currently available drugs are limited, however. Poor tolerability and toxicity may also compromise the long-term prospects of antiretroviral therapy. Nevertheless, benefits of antiretroviral therapy far outweigh the downsides and efforts to scale up responsible use of antiretroviral agents in developing countries are a priority in the fight against HIV/AIDS. This paper presents an overview of antiretroviral therapy and resistance to antiretroviral drugs.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Vacinas contra a AIDS , Fármacos Anti-HIV/classificação , Fármacos Anti-HIV/farmacologia , Terapia Antirretroviral de Alta Atividade/métodos , Países em Desenvolvimento , Interações Medicamentosas , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , Inibidores da Protease de HIV/uso terapêutico , Transcriptase Reversa do HIV/antagonistas & inibidores , Prioridades em Saúde , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Seleção de Pacientes , Prevenção Primária/métodos , Inibidores da Transcriptase Reversa/uso terapêutico , Resultado do Tratamento
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