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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.
STAR Protoc ; 4(4): 102576, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37733596

RESUMO

The lymph node (LN) is a critical biological site for immune maturation after vaccination as it includes several cell populations critical for priming the antibody response. Here, we present a protocol for sampling the LN and isolating cell populations to evaluate immunogens targeting germline cells. We describe steps for media and tube preparation and sample collection using an ultrasound-guided LN fine-needle aspiration procedure. This protocol is safe, quick, low-cost, and less invasive than excisional biopsy. For complete details on the use and execution of this protocol, please refer to Leggat et al. (2022).1.


Assuntos
Centro Germinativo , Linfonodos , Humanos , Biópsia por Agulha Fina , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Vacinação , Ultrassonografia de Intervenção
3.
Nat Med ; 29(9): 2334-2346, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37640860

RESUMO

Vaccine protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection wanes over time, requiring updated boosters. In a phase 2, open-label, randomized clinical trial with sequentially enrolled stages at 22 US sites, we assessed safety and immunogenicity of a second boost with monovalent or bivalent variant vaccines from mRNA and protein-based platforms targeting wild-type, Beta, Delta and Omicron BA.1 spike antigens. The primary outcome was pseudovirus neutralization titers at 50% inhibitory dilution (ID50 titers) with 95% confidence intervals against different SARS-CoV-2 strains. The secondary outcome assessed safety by solicited local and systemic adverse events (AEs), unsolicited AEs, serious AEs and AEs of special interest. Boosting with prototype/wild-type vaccines produced numerically lower ID50 titers than any variant-containing vaccine against all variants. Conversely, boosting with a variant vaccine excluding prototype was not associated with decreased neutralization against D614G. Omicron BA.1 or Beta monovalent vaccines were nearly equivalent to Omicron BA.1 + prototype or Beta + prototype bivalent vaccines for neutralization of Beta, Omicron BA.1 and Omicron BA.4/5, although they were lower for contemporaneous Omicron subvariants. Safety was similar across arms and stages and comparable to previous reports. Our study shows that updated vaccines targeting Beta or Omicron BA.1 provide broadly crossprotective neutralizing antibody responses against diverse SARS-CoV-2 variants without sacrificing immunity to the ancestral strain. ClinicalTrials.gov registration: NCT05289037 .


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacinas contra COVID-19/efeitos adversos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Anticorpos Amplamente Neutralizantes
4.
Curr Opin Virol ; 60: 101331, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37187125

RESUMO

Viral-associated cancers are a distinct group of malignancies with a unique pathogenesis and epidemiology. Liquid biopsy is a minimally invasive way to identify tumor-associated abnormalities in blood derivatives, such as plasma, to guide the diagnosis, prognosis, and treatment of patients with cancer. Liquid biopsy encompasses a multitude of circulating analytes with the most extensively studied being cell-free DNA (cfDNA). In recent decades, substantial advances have been made toward the study of circulating tumor DNA in nonviral-associated cancers. Many of these observations have been translated to the clinic to improve the outcomes of patients with cancer. The study of cfDNA in viral-associated cancers is rapidly evolving and reveals tremendous potential for clinical applications. This review provides an overview of the pathogenesis of viral-associated malignancies, the current state of cfDNA analysis in oncology, the current state of cfDNA analysis in viral-associated cancers, and perspectives for the future of liquid biopsies in viral-associated cancers.


Assuntos
Ácidos Nucleicos Livres , Neoplasias , Humanos , Ácidos Nucleicos Livres/genética , Biomarcadores Tumorais/genética , Neoplasias/diagnóstico , Neoplasias/genética , Biópsia Líquida , Prognóstico
5.
PLoS One ; 18(4): e0284305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37043507

RESUMO

Detection of anti-Strongyloides IgG in urine by enzyme-linked immunosorbent assay (ELISA) for diagnosis of strongyloidiasis reportedly has comparable performance to conventional serum assays. Initial comparisons of urine assays using commercial ELISA kits designated for serology have shown its diagnostic potential but sub-optimal accuracy. In the present study, we optimized urine ELISA protocols based on different antigen types and evaluated their accuracies in determining the epidemiology of strongyloidiasis in Northeast Thailand. Paired urine and fecal samples of 966 individuals from the study community were collected for three consecutive days and tested for strongyloidiasis. We compared three ELISA protocols using different antigens including crude S. stercoralis antigen (Ss-ELISA), crude S. ratti antigen (Sr-ELISA) and recombinant NIE antigen (NIE-ELISA) and fecal examination by agar plate-culture (APCT) technique and formalin-ethyl acetate concentration technique (FECT). The optimized ELISA protocols using three different antigen sources yielded significantly higher prevalence rates of strongyloidiasis (58.9-65.1%) than those by fecal examination methods (19.7%). The prevalence of strongyloidiasis determined by ELISA protocols significantly increased with age (p value < 0.0001) and males had higher prevalence than females (p value < 0.0001). Diagnostic agreements between ELISA protocols were moderate (κ = 0.461-0.586) and the agreement between each ELISA protocol and fecal examinations were slight (κ = 0.139-0.210). The results obtained by urine ELISA protocols using three different antigens showed comparable diagnostic performances, provided further supports for the utility of urine as an alternative clinical specimen for diagnosis of strongyloidiasis.


Assuntos
Parasitos , Strongyloides stercoralis , Estrongiloidíase , Masculino , Animais , Feminino , Humanos , Estrongiloidíase/diagnóstico , Estrongiloidíase/epidemiologia , Tailândia/epidemiologia , Anticorpos Anti-Helmínticos , Ensaio de Imunoadsorção Enzimática/métodos , Antígenos de Helmintos , Fezes , Proteínas Recombinantes , Imunoglobulina G , Sensibilidade e Especificidade
6.
Viruses ; 14(12)2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36560778

RESUMO

Epidemic Kaposi's sarcoma (KS), defined by co-infection with Human Herpes Virus 8 (HHV-8) and the Human Immunodeficiency Virus (HIV), is a major cause of mortality in sub-Saharan Africa. Antiretroviral therapy (ART) significantly reduces the risk of developing KS, and for those with KS, tumors frequently resolve with ART alone. However, for unknown reasons, a significant number of KS cases do not resolve and can progress to death. To explore how HIV responds to ART in the KS tumor microenvironment, we sequenced HIV env-nef found in DNA and RNA isolated from plasma, peripheral blood mononuclear cells, and tumor biopsies, before and after ART, in four Ugandan study participants who had unresponsive or progressive KS after 180-250 days of ART. We performed immunohistochemistry experiments to detect viral proteins in matched formalin-fixed tumor biopsies. Our sequencing results showed that HIV diversity and RNA expression in KS tumors are maintained after ART, despite undetectable plasma viral loads. The presence of spliced HIV transcripts in KS tumors after ART was consistent with a transcriptionally active viral reservoir. Immunohistochemistry staining found colocalization of HIV Nef protein and tissue-resident macrophages in the KS tumors. Overall, our results demonstrated that even after ART reduced plasma HIV viral load to undetectable levels and restored immune function, HIV in KS tumors continues to be transcriptionally and translationally active, which could influence tumor maintenance and progression.


Assuntos
Infecções por HIV , Herpesvirus Humano 8 , Sarcoma de Kaposi , Produtos do Gene nef do Vírus da Imunodeficiência Humana , Humanos , Produtos do Gene nef , Herpesvirus Humano 8/genética , HIV/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Leucócitos Mononucleares/patologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , RNA , Microambiente Tumoral
7.
medRxiv ; 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35898343

RESUMO

Background: Protection from SARS-CoV-2 vaccines wanes over time and is compounded by emerging variants including Omicron subvariants. This study evaluated safety and immunogenicity of SARS-CoV-2 variant vaccines. Methods: This phase 2 open-label, randomized trial enrolled healthy adults previously vaccinated with a SARS-CoV-2 primary series and a single boost. Eligible participants were randomized to one of six Moderna COVID19 mRNA vaccine arms (50µg dose): Prototype (mRNA-1273), Omicron BA.1+Beta (1 or 2 doses), Omicron BA.1+Delta, Omicron BA.1 monovalent, and Omicron BA.1+Prototype. Neutralization antibody titers (ID 50 ) were assessed for D614G, Delta, Beta and Omicron BA.1 variants and Omicron BA.2.12.1 and BA.4/BA.5 subvariants 15 days after vaccination. Results: From March 30 to May 6, 2022, 597 participants were randomized and vaccinated. Median age was 53 years, and 20% had a prior SARS-CoV-2 infection. All vaccines were safe and well-tolerated. Day 15 geometric mean titers (GMT) against D614G were similar across arms and ages, and higher with prior infection. For uninfected participants, Day 15 Omicron BA.1 GMTs were similar across Omicron-containing vaccine arms (3724-4561) and higher than Prototype (1,997 [95%CI:1,482-2,692]). The Omicron BA.1 monovalent and Omicron BA.1+Prototype vaccines induced a geometric mean ratio (GMR) to Prototype for Omicron BA.1 of 2.03 (97.5%CI:1.37-3.00) and 1.56 (97.5%CI:1.06-2.31), respectively. A subset of samples from uninfected participants in four arms were also tested in a different laboratory at Day 15 for neutralizing antibody titers to D614G and Omicron subvariants BA.1, BA.2.12.2 and BA.4/BA.5. Omicron BA.4/BA.5 GMTs were approximately one third BA.1 GMTs (Prototype 517 [95%CI:324-826] vs. 1503 [95%CI:949-2381]; Omicron BA.1+Beta 628 [95%CI:367-1,074] vs. 2125 [95%CI:1139-3965]; Omicron BA.1+Delta 765 [95%CI:443-1,322] vs. 2242 [95%CI:1218-4128] and Omicron BA.1+Prototype 635 [95%CI:447-903] vs. 1972 [95%CI:1337-2907). Conclusions: Higher Omicron BA.1 titers were observed with Omicron-containing vaccines compared to Prototype vaccine and titers against Omicron BA.4/BA.5 were lower than against BA.1 for all candidate vaccines. Clinicaltrialsgov: NCT05289037.

8.
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
9.
Biologicals ; 74: 16-23, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620540

RESUMO

There is an increasing need to establish quality principles for designing, developing and manufacturing challenge agents as currently these agents are classified differently by various jurisdictions. Indeed, considerations for challenge agent manufacturing vary between countries due to differences in regulatory oversight, the categorization of the challenge agent and incorporation into medicinal/vaccine development processes. To this end, a whitepaper on the guidance has been produced and disseminated for consultation to researchers, regulatory experts and regulatory or advisory bodies. This document is intended to discuss fundamental principles of selection, characterization, manufacture, quality control and storage of challenge agents for international reference. In the development phase, CMC documentation is needed for a candidate challenge agent, while standard operating procedure documentation is needed to monitor and control the manufacturing process, followed by use of qualified methods to test critical steps in the manufacturing process, or the final product itself. These activities are complementary: GMP rules, which intervene only at the time of the routine manufacturing of batches, do not contribute to the proper development and qualification of the candidate product. Some considerations regarding suitability of premises for challenge manufacturing was discussed in the presentation dedicated to "routine manufacturing".


Assuntos
Pesquisa Biomédica/normas , Desenvolvimento de Medicamentos , Experimentação Humana , Desenvolvimento de Vacinas , Humanos , Controle de Qualidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-34328562

RESUMO

In this chapter, we describe the scientific, technical, clinical and regulatory aspects of establishing a controlled human hookworm infection (CHHI) model in non-endemic and endemic geographical regions, to facilitate a pathway towards accelerated vaccine development. The success achieved in establishing the CHHI platform specifically allows the Human Hookworm Vaccine Initiative (HHVI) to accelerate its progress by establishing a human hookworm vaccination/challenge model (HVCM) in a hookworm endemic area of Brazil. The HVCM will permit the rapid and robust determination of clinical efficacy in adults, allowing for early selection of the most efficacious human hookworm vaccine (HHV) candidate(s) to advance into later-stage pivotal paediatric clinical trials and reduce the overall number of participants required to assess efficacy (Diemert et al. 2018).

11.
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
12.
PLoS Negl Trop Dis ; 14(7): e0008296, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32614828

RESUMO

The World Health Organization (WHO) has defined moderate-to-heavy intensity (M&HI) infections with soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura and the two hookworms, Ancylostoma duodenale and Necator americanus) based on specific values of eggs per gram of stool, as measured by the Kato-Katz method. There are a variety of novel microscopy and DNA-based methods but it remains unclear whether applying current WHO thresholds on to these methods allows for a reliable classification of M&HI infections. We evaluated both WHO and method-specific thresholds for classifying the M&HI infections for novel microscopic (FECPAKG2, McMaster and Mini-FLOTAC) and DNA-based (qPCR) diagnostic methods. For this, we determined method-specific thresholds that best classified M&HI infections (defined by Kato-Katz and WHO thresholds; reference method) in two multi-country drug efficacy studies. Subsequently, we verified whether applying these method-specific thresholds improved the agreement in classifying M&HI infections compared to the reference method. When we applied the WHO thresholds, the new microscopic methods mainly misclassified M&HI as low intensity, and to a lesser extent low intensity infection as M&HI. For FECPAKG2, applying the method-specific thresholds significantly improved the agreement for Ascaris (moderate → substantial), Trichuris and hookworms (fair → moderate). For Mini-FLOTAC, a significantly improved agreement was observed for hookworms only (fair → moderate). For the other STHs, the agreement was almost perfect and remained unchanged. For McMaster, the method-specific thresholds revealed a fair to a substantial agreement but did not significantly improve the agreement. For qPCR, the method-specific thresholds based on genome equivalents per ml of DNA moderately agreed with the reference method for hookworm and Trichuris infections. For Ascaris, there was a substantial agreement. We defined method-specific thresholds that improved the classification of M&HI infections. Validation studies are required before they can be recommended for general use in assessing M&HI infections in programmatic settings.


Assuntos
Helmintíase/classificação , Microscopia/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Solo/parasitologia , Helmintíase/diagnóstico , Helmintíase/transmissão , Humanos , Organização Mundial da Saúde
13.
PLoS Negl Trop Dis ; 14(5): e0008237, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453752

RESUMO

The human hookworm Necator americanus infects more than 400 million people worldwide, contributing substantially to the poverty in these regions. Adult stage N. americanus live in the small intestine of the human host where they inject excretory/secretory (ES) products into the mucosa. ES products have been characterized at the proteome level for a number of animal hookworm species, but until now, the difficulty in obtaining sufficient live N. americanus has been an obstacle in characterizing the secretome of this important human pathogen. Herein we describe the ES proteome of N. americanus and utilize this information along with RNA Seq data to conduct the first proteogenomic analysis of a parasitic helminth, significantly improving the available genome and thereby generating a robust description of the parasite secretome. The genome annotation resulted in a revised prediction of 3,425 fewer genes than initially reported, accompanied by a significant increase in the number of exons and introns, total gene length and the percentage of the genome covered by genes. Almost 200 ES proteins were identified by LC-MS/MS with SCP/TAPS proteins, 'hypothetical' proteins and proteases among the most abundant families. These proteins were compared to commonly used model species of human parasitic infections, including Ancylostoma caninum, Nippostrongylus brasiliensis and Heligmosomoides polygyrus. SCP/TAPS proteins are immunogenic in nematode infections, so we expressed four of those identified in this study in recombinant form and showed that they are all recognized to varying degrees by serum antibodies from hookworm-infected subjects from a disease-endemic area of Brazil. Our findings provide valuable information on important families of proteins with both known and unknown functions that could be instrumental in host-parasite interactions, including protein families that might be key for parasite survival in the onslaught of robust immune responses, as well as vaccine and diagnostic targets.


Assuntos
Necator americanus/metabolismo , Proteoma , Animais , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genoma Helmíntico , Proteínas de Helminto , Necator americanus/genética , Filogenia
14.
Blood ; 133(12): 1313-1324, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30617194

RESUMO

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.


Assuntos
Biomarcadores Tumorais/genética , Linfoma de Burkitt/genética , Infecções por Vírus Epstein-Barr/complicações , Genes de Imunoglobulinas , Genoma Humano , Mutação , Transcriptoma , Adolescente , Adulto , Linfoma de Burkitt/patologia , Linfoma de Burkitt/virologia , Criança , Pré-Escolar , Estudos de Coortes , Citidina Desaminase/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Adulto Jovem
15.
Acta Trop ; 189: 124-128, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30321522

RESUMO

Inflammation of the hepatobiliary system in chronic opisthorchiasis is associated with an elevated level of urinary 8-oxo-7,8 dihydro-2'deoxyguanosine (8-oxodG) during active as well as past exposure to Opisthorchis viverrini infection. In this study, we evaluated the short-term effect of praziquantel treatment on hepatobiliary disease (HBD) using urinary 8-oxodG as an inflammatory marker in a cohort of residents in endemic areas of opisthorchiasis in Khon Kaen, Thailand. The HBD status in terms of periductal fibrosis (PDF) was determined by abdominal ultrasonography and O. viverrini infection was monitored at baseline and 2-4 weeks after curative treatment by praziquantel. Analysis of O. viverrini-infected participants who were PDF-ve revealed that there was a significant reduction of urinary 8-oxodG after treatment compared with the baseline levels (p < 0.001). By contrast, in PDF+ve individuals, the levels of urinary 8-oxodG were similar between baseline and those post-treatment. Although confirmation by using a larger sample size is needed, the positive association between HBD and urinary 8-oxodG level after worm clearance suggests that chronic hepatobiliary inflammation is neither affected nor interrupted by short-term praziquantel treatment. Individuals with persistent PDF at pre- and post-treatment who have a high risk of cholangiocarcinoma, could be identified within 2-4 weeks after parasite removal by drug treatment. Thus, urinary 8-oxodG is a useful biomarker for predicting persistent PDF in individuals with a recent drug treatment history who require further clinical investigation, management and treatment.


Assuntos
Anti-Helmínticos/farmacologia , Desoxiguanosina/análogos & derivados , Opistorquíase/tratamento farmacológico , Praziquantel/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Animais , Doenças Biliares/parasitologia , Biomarcadores/urina , Desoxiguanosina/urina , Feminino , Humanos , Hepatopatias/parasitologia , Masculino , Pessoa de Meia-Idade , Opistorquíase/complicações
16.
Am J Trop Med Hyg ; 100(1): 127-129, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30398144

RESUMO

To evaluate the accuracy and reliability of urine assay for the diagnosis of strongyloidiasis, three different immunoassays were used to assess the diagnostic accuracy of anti-Strongyloides immunoglobulin G (IgG) in urine and compared with those in serum samples. Analyses by InBios enzyme-linked immunosorbent assay (ELISA) kit (recombinant NIE antigen), SciMedx ELISA kit (Strongyloides stercoralis antigen), and our in-house ELISA (Strongyloides ratti antigen) yielded comparable diagnostic performances between urine and serum assays. Levels of Strongyloides-specific IgG in urine significantly correlated with those in serum. Tests for diagnostic agreement between urine and serum IgG assays showed substantial to fair agreement (κ = 0.207-0.615). The observed quantitative and qualitative concordance between urine and serum assays in strongyloidiasis suggests that urine has similar diagnostic value to that for serum. Because of the ease and noninvasiveness of clinical sample collection, urine assay has a high potential for the initial diagnosis and mass screening of strongyloidiasis.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/urina , Ensaio de Imunoadsorção Enzimática/normas , Imunoglobulina G/sangue , Imunoglobulina G/urina , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/diagnóstico , Idoso , Animais , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Strongyloides stercoralis/imunologia , Estrongiloidíase/sangue , Estrongiloidíase/urina
17.
PLoS One ; 13(11): e0207405, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30440021

RESUMO

Modulation or prevention of protein changes during the cholangiocarcinoma (CCA) process induced by Opisthorchis viverrini (Ov) infection may become a key strategy for prevention and treatment of CCA. Monitoring of such changes could lead to discovery of protein targets for CCA treatment. Curcumin exerts anti-inflammatory and anti-CCA activities partly through its protein-modulatory ability. To support the potential use of curcumin and to discover novel target molecules for CCA treatment, we used a quantitative proteomic approach to investigate the effects of curcumin on protein changes in an Ov-induced CCA-harboring hamster model. Isobaric labelling and tandem mass spectrometry were used to compare the protein expression profiles of liver tissues from CCA hamsters with or without curcumin dietary supplementation. Among the dysregulated proteins, five were upregulated in liver tissues of CCA hamsters but markedly downregulated in the CCA hamsters supplemented with curcumin: S100A6, lumican, plastin-2, 14-3-3 zeta/delta and vimentin. Western blot and immunohistochemical analyses also showed similar expression patterns of these proteins in liver tissues of hamsters in the CCA and CCA + curcumin groups. Proteins such as clusterin and S100A10, involved in the NF-κB signaling pathway, an important signaling cascade involved in CCA genesis, were also upregulated in CCA hamsters and were then suppressed by curcumin treatment. Taken together, our results demonstrate the important changes in the proteome during the genesis of O. viverrini-induced CCA and provide an insight into the possible protein targets for prevention and treatment of this cancer.


Assuntos
Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Curcumina/administração & dosagem , Proteômica , Proteínas 14-3-3/genética , Animais , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/prevenção & controle , Quimioprevenção , Colangiocarcinoma/complicações , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Cricetinae , Modelos Animais de Doenças , Fasciola hepatica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Lumicana/genética , Glicoproteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Opistorquíase/complicações , Opistorquíase/tratamento farmacológico , Opistorquíase/genética , Opistorquíase/patologia , Opisthorchis/patogenicidade , Proteína A6 Ligante de Cálcio S100/genética , Vimentina/genética
18.
Pediatr Infect Dis J ; 37(12): 1290-1293, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30408008

RESUMO

Zika virus is a mosquito-borne virus that causes congenital Zika syndrome, characterized by microcephaly and other fetal brain anomalies. This case report presents a case of Zika virus-related fetal brain anomalies including pathologic evidence of cerebral neuronal apoptosis and macrophage infiltrates and intracerebral calcification, ventriculomegaly and corpus callosum dysgenesis detected by ultrasound at 18 weeks of pregnancy.


Assuntos
Encéfalo/diagnóstico por imagem , Doenças do Sistema Nervoso/virologia , Ultrassonografia Pré-Natal/métodos , Infecção por Zika virus/diagnóstico por imagem , Adulto , Encéfalo/patologia , Feminino , Humanos , Doenças do Sistema Nervoso/diagnóstico por imagem , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Segundo Trimestre da Gravidez , Zika virus , Infecção por Zika virus/congênito
20.
Trends Parasitol ; 34(9): 747-758, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30064902

RESUMO

Helminthic parasites are important targets for vaccine research as they infect an estimated 1 billion people worldwide. Despite significant progress in the discovery of defined antigens as candidates for vaccines, the potential of a helminth vaccine advancing to an investigational product to be tested in humans remains as challenging as it did 50 years ago. Candidate helminth vaccines must still advance along a 'critical path' of preclinical research, vaccine process development (which includes 'chemistry, manufacturing, and controls' or CMC), current good manufacturing practice (cGMP) production of the vaccine, and clinical trials. This path is highly targeted towards meeting the safety, immunogenicity, and efficacy criteria of regulatory bodies such as the US Food and Drug Administration (FDA). For nearly 20 years our product development partnership (PDP), the Texas Children's Hospital Center for Vaccine Development (TCH-CVD), has followed the critical paths of several novel subunit vaccines for the human hookworm Necator americanus and the intestinal trematode Schistosoma mansoni. Herein, we describe the critical lessons learned along this critical path.


Assuntos
Helmintíase/prevenção & controle , Vacinas de Subunidades Antigênicas , Helmintíase/imunologia , Humanos , Vacinas de Subunidades Antigênicas/normas
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