Tropical Medicine Commons^™

Na-Gst-1 Adsorbed On Alhydrogel Co-Administered With Different Toll-Like Receptor Agonists In Hookworm-Naive Adults Using A Controlled Human Infection Model In The Usa: A Phase 2, Double-Blind, Randomised Controlled Trial, Caroline K Dirosato, Elissa M Malkin, Sean M Lee, Guacyara Erwin, Lara Hoeweler, Larissa Scholte, Maria Elena Bottazzi, David I Pritchard, Peter J Hotez, Jeffrey M Bethony, David J Diemert

Faculty, Staff and Students Publications

Background: Necator americanus glutathione S-transferase-1 (Na-GST-1) performs a crucial enzymatic step in hookworm blood feeding and is a leading target for vaccine development. Phase 1 trials in Brazil, Gabon, and the USA of recombinant Na-GST-1 adsorbed on Alhydrogel (Na-GST-1/Al), co-administered with or without AP 10-701 (Toll-like receptor [TLR] 4 agonist) or CpG 10104 (TLR9 agonist), showed the vaccine was well tolerated, safe, and immunogenic. A controlled human hookworm infection (CHHI) model was previously developed to evaluate the effect of candidate hookworm vaccines on infection. We aimed to assess the effect of vaccination with three different Na-GST-1 vaccine formulations on subsequent …

Helminth-Infected Mozambican Children With Malaria Have Increased Anaemia, Cytokines And Helminth-Specific Antibodies, Inocência Cuamba, Rebeca Santano, Berta Grau-Pujol, Marta Vidal, Anélsio Cossa, Chenjerai Jairoce, Rojelio Mejía, José Muñoz, Ruth Aguilar, Bin Zhan, Augusto Nhabomba, Gemma Moncunill, Carlota Dobaño

Faculty, Staff and Students Publications

Owing to their overlapping geographical distribution and the consequent occurrence of coinfections, several studies have evaluated the impact of helminth infections on malaria immune responses and clinical outcomes. However, little has been reported on how malaria coinfection affects anthelmintic responses in children harbouring worm infections. We therefore aimed to assess the impact of malaria coinfection on helminth-related clinical and immune outcomes in children. Here, we measured in plasma the levels of 30 cytokines, total IgE, and helminth-specific IgM, IgA, IgG, IgG1-4, and IgE antibodies to a panel of 11 helminth antigens by Luminex. Samples were obtained from 441 children aged …

Ixodid And Flea Infestations And Associated Bacteria On Two Sympatric Felid Species In South Texas, Allan T Showler, Hilary Swarts, Maya Murry, Alisa Nelson, Alexander R Kneubehl, Sarah M Gunter

Faculty, Staff and Students Publications

Ixodid ticks and fleas parasitize wild felids and can transmit pathogens of veterinary and public health concern. We identified ixodid and flea species collected from sympatric South Texas bobcats, L. rufus, and ocelots, L. pardalis. Greater diversities of ixodids were found on both felids than in previous reports, with seven species in three genera on L. rufus and six species in three genera on L. pardalis. We report first findings of tropical horse tick, Dermacentor nitens, on L. rufus in Texas, and Ixodes keiransi on both felids in Texas. Although false cayenne tick, Amblyomma tenellum, nymphs were the most abundant …

Alterations Of The Upper Respiratory Microbiome Among Children Living With Hiv Infection In Botswana, Sweta M Patel, John Farirai, Mohamed Z Patel, Sifelane Boiditswe, Leabaneng Tawe, Shimane Lekalake, Mogomotsi Matshaba, Andrew P Steenhoff, Tonya Arscott-Mills, Kristen A Feemster, Samir S Shah, Nathan Thielman, Coleen K Cunningham, Lawrence A David, David M Murdoch, Matthew S Kelly

Faculty, Staff and Students Publications

Children living with HIV (CLWH) are at high risk of colonization and infection by respiratory pathogens, though this risk can be reduced by other microbes in the upper respiratory microbiome. The impact of HIV infection on the pediatric upper respiratory microbiome is poorly understood, and we sought to address this knowledge gap by identifying associations between HIV infection and the nasopharyngeal microbiomes of Batswana children. We enrolled Batswana CLWH (< 5 years) and age- and sex-matched HIV-exposed, uninfected and HIV-unexposed, uninfected children in a cross-sectional study. We used shotgun metagenomic sequencing to compare nasopharyngeal microbiomes by HIV status. Among the 143 children in this study, HIV and HIV-associated immunosuppression were associated with alterations in nasopharyngeal microbiome composition, including lower abundances of Corynebacterium species associated with resistance to bacterial pathogen colonization. These findings suggest that the upper respiratory microbiome may contribute to the high risk of respiratory infections among CLWH.

A Honduran Prevalence Study On Soil-Transmitted Helminths Highlights Serological Antibodies To Tm-Wap49 As A Diagnostic Marker For Exposure To Human Trichuriasis, Neima Briggs, Leroy Versteeg, Rojelio Mejia, Jeroen Pollet, Maria Jose Villar, Bin Zhan, Graeme Segal, Stephanie Novak, Patricia Lenihan, Paul Musgrave, Viviana Ellis, Carol Florencia Coello, K Jagannadha Sastry, Joe Craft, Peter J Hotez, Maria Elena Bottazzi

Faculty, Staff and Student Publications

Soil-transmitted helminth (STH) infections rank among the most prevalent communicable diseases of humans, yet detection of these parasites is mostly restricted to identifying active infection through fecal examinations. Currently, there are no commercial diagnostic tools to identify a prior whipworm or hookworm exposure, and the few serological assays for roundworm infection have not been well validated for crossreactivity or infections in humans. Such diagnostic restrictions limit the range of scientific and clinical questions that surround STH exposures and their implicated relationship to chronic diseases, such as autoimmunity, allergy, and cancer. The goal of this investigation was to evaluate the diagnostic …

Identification And Characterization Of A Novel Pavlovskyella (Acari: Argasidae) From Chile, Parasite Of The Culpeo Fox (Lycalopex Culpaeus), Sebastián Muñoz-Leal, Alexander R Kneubehl, Karen Ardiles, Catalina Parragué-Migone, Ignacio Troncoso-Toro, Pablo Oyarzún-Ruiz, Job E Lopez

Faculty, Staff and Students Publications

Soft ticks (Argasidae) of the subgenus Pavlovskyella Pospelova-Shtrom are worldwide distributed parasites of medical importance. However, the systematics of the subgenus are currently under debate because genetic data shows that the group is paraphyletic. Meanwhile, species of Pavlovskyella continue to be discovered. In this study a novel species of the subgenus is described from specimens collected on a fox in central Chile. The larva of this new species differentiates from other Pavlovskyella spp. by having the following combination of characters: subpyriform dorsal plate; 15 pairs of setae, 7 anterolateral, 3 central, and 5 posterolateral, and hypostome with denticles in the …

Randomized, Observer-Blind, Controlled Phase 1 Study Of The Safety And Immunogenicity Of The Na-Gst-1/Alhydrogel Hookworm Vaccine With Or Without A Cpg Odn Adjuvant In Hookworm-Naïve Adults, David J Diemert, Maria Zumer, Mark Bova, Christina Gibbs-Tewary, Elissa M Malkin, Doreen Campbell, Lara Hoeweler, Guangzhao Li, Maria Elena Bottazzi, Peter J Hotez, Jeffrey M Bethony

Faculty, Staff and Students Publications

BACKGROUND: Recombinant Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) formulated on Alhydrogel (Na-GST-1/Alhydrogel) is being developed to prevent anemia and other complications of N. americanus infection. Antibodies induced by vaccination with recombinant Na-GST-1 are hypothesized to interfere with the blood digestion pathway of adult hookworms in the host. Phase 1 trials have demonstrated the safety of Na-GST-1 formulated on Alhydrogel, but further optimization of the vaccine adjuvant formulation may improve humoral immune responses, thereby increasing the likelihood of vaccine efficacy.

METHODS: A randomized, observer-blind, dose escalation Phase 1 trial was conducted in 24 healthy, hookworm-naïve adults. In each cohort of 12 participants, 4 …

Therapeutic Effect Of Recombinant Echinococcus Granulosus Antigen B Subunit 2 Protein On Sepsis In A Mouse Model, Ya-Yun Qian, Fei-Fei Huang, Si-Yu Chen, Wei-Xiao Zhang, Yin Wang, Peng-Fei Du, Gen Li, Wen-Bo Ding, Lei Qian, Bin Zhan, Liang Chu, Dong-Hui Jiang, Xiao-Di Yang, Rui Zhou

Faculty, Staff and Students Publications

BACKGROUND: Sepsis is a potentially fatal systemic inflammatory response syndrome (SIRS) that threatens millions of lives worldwide. Echinococcus granulosus antigen B (EgAgB) is a protein released by the larvae of the tapeworm. This protein has been shown to play an important role in modulating host immune response. In this study we expressed EgAgB as soluble recombinant protein in E. coli (rEgAgB) and explored its protective effect on sepsis.

METHODS: The sepsis model was established by cecal ligation and puncture (CLP) procedure in BALB/c mice. The therapeutic effect of rEgAgB on sepsis was performed by interperitoneally injecting 5 µg rEgAgB in …

A Comparison Of The Diagnostic Capability Of Kato-Katz And Real-Time Pcr For The Assessment Of Treatment Efficacy Of Ivermectin And Albendazole Combination Against T Trichiura Infections, Gabriela Matamoros, Ana Sanchez, Ruben Cimino, Alejandro Krolewiecki, Rojelio Mejia

Faculty, Staff and Students Publications

BACKGROUND: Trichuris trichiura is humans' second most prevalent soil-transmitted helminth (STH) infection after Ascaris lumbricoides, affecting approximately 460 million people worldwide. Despite its sub-optimal sensitivity, especially in low prevalence and infection intensity settings, the modified Kato-Katz (K-K) is still recommended as a diagnostic method by the World Health organization (WHO) guidelines.

METHODOLOGY/PRINCIPAL FINDINGS: Within a randomized clinical trial (RCT) comprising four treatment arms with two different anthelmintics, the present study reports an important secondary research objective to determine the diagnostic agreement between K-K and real-time PCR evaluating treatment efficacy against T. trichiura. The parasitological results were analyzed, including cure rates …

Description Of A New Pavlovskyella Species (Acari: Argasidae) From Chile, Sebastián Muñoz-Leal, José M Venzal, Alexander R Kneubehl, Job E Lopez, Thiago F Martins, Marcelo B Labruna

Faculty, Staff and Students Publications

Soft ticks (Argasidae) of the Pavlovskyella Pospelova-Shtrom subgenus are important vectors of relapsing fever spirochetes, which are agents of disease globally. South American representatives of the Pavlovskyella subgenus include 3 species: Ornithodoros (Pavlovskyella) brasiliensis Aragão, Ornithodoros (Pavlovskyella) furcosus Neumann, and Ornithodoros (Pavlovskyella) rostratus Aragão. Here, we describe a fourth species based on morphological and mitogenomic evidence of ticks collected in burrows of unknown hosts in central Chile. The larva of the new species separates from other South American soft ticks by the following combination of characters: 13 pairs of dorsolateral setae, dorsal plate hexagonal, hypostome blunt with denticles from apex …

Rationalization Of The Laboratory Diagnosis For Good Management Of Malaria: Lessons From Transitional Methods, Neguemadji N. Ngaba, Imteyaz A. Khan, Namrata Hange, Maria Kezia Lourdes Ligsay Pormento, Manoj Kumar Reddy Somagutta, Ajay Kumar, Youssouf Abdelkerim, Alarangue Djindimadje, Samia Jahan

Ateneo School of Medicine and Public Health Publications

Introduction. Malaria is an endemic disease in sub-Saharan Africa. In clinical practice, the main concern is the overdiagnosis of malaria leading to inappropriate drug prescription without laboratory confirmation. Objective. This study aimed to evaluate clinical examination reliability compared with translational laboratory methods of malaria diagnosis. Methods. The study was conducted in Goundi Hospital among hospitalized patients over a seven-month period. Patients were interviewed, and malaria tests done included the Giemsa-stained thick and thin blood smears. Diagnostic accuracy was analysed by calculating sensitivity, specificity, and predictive values. Results. Among 1,874 participants, 674 (35.96%) patients had positive Giemsa-stained …

Analysis Of The Immunological Biomarker Profile During Acute Zika Virus Infection Reveals The Overexpression Of Cxcl10, A Chemokine Linked To Neuronal Damage., Felipe Gomes Naveca, Gemilson Soares Pontes, Aileen Yu-Hen Chang, George Allan Villarouco Da Silva, Valdinete Alves Do Nascimento, Dana Cristina Da Silva Monteiro, +Several Additional Authors

Medicine Faculty Publications

BACKGROUND: Infection with Zika virus (ZIKV) manifests in a broad spectrum of disease ranging from mild illness to severe neurological complications and little is known about Zika immunopathogenesis.

OBJECTIVES: To define the immunologic biomarkers that correlate with acute ZIKV infection.

METHODS: We characterized the levels of circulating cytokines, chemokines, and growth factors in 54 infected patients of both genders at five different time points after symptom onset using microbeads multiplex immunoassay; comparison to 100 age-matched controls was performed for statistical analysis and data mining.

FINDINGS: ZIKV-infected patients present a striking systemic inflammatory response with high levels of pro-inflammatory mediators. Despite …