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Parasites & Vectors May 2024The giant roundworm Ascaris is an intestinal nematode, causing ascariasis by infecting humans and pigs worldwide. Recent estimates suggest that Ascaris infects over half...
BACKGROUND
The giant roundworm Ascaris is an intestinal nematode, causing ascariasis by infecting humans and pigs worldwide. Recent estimates suggest that Ascaris infects over half a billion people, with chronic infections leading to reduced growth and cognitive ability. Ascariasis affects innumerable pigs worldwide and is known to reduce production yields via decreased growth and condemnation of livers. The predominant anthelminthic drugs used to treat ascariasis are the benzimidazoles. Benzimidazoles interact with β-tubulins and block their function, and several benzimidazole resistance-associated mutations have been described in the β-tubulins of ruminant nematodes. Recent research on ascarids has shown that these canonical benzimidazole resistance-associated mutations are likely not present in the β-tubulins of Ascaris, Ascaridia or Parascaris, even in phenotypically resistant populations.
METHODS
To further determine the putative absence of key β-tubulin polymorphisms, we screened two β-tubulin isotypes of Ascaris, highly expressed in adult worms. Using adult and egg samples of Ascaris obtained from pigs and humans worldwide, we performed deep amplicon sequencing to look for canonical resistance-associated mutations in Ascaris β-tubulins. Subsequently, we examined these data in closer detail to study the population dynamics of Ascaris and genetic diversity within the two isotypes and tested whether genotypes appeared to partition across human and pig hosts.
RESULTS
In the 187 isolates, 69 genotypes were found, made up of eight haplotypes of β-tubulin isotype A and 20 haplotypes of isotype B. Single nucleotide polymorphisms were seen at 14 and 37 positions for β-tubulin isotype A and isotype B, respectively. No evidence of any canonical benzimidazole resistance-associated mutations was found in either human- or pig-derived Ascaris isolates. There was, however, a difference in the genetic diversity of each isotype and distribution of β-tubulin genotypes between human- and pig-derived Ascaris. Statistical tests of population differentiation show significant differences (p < 0.001) between pig- and human-derived worms; however, more diversity was seen between worms from different populations than worms from different hosts.
CONCLUSIONS
Our work suggests an absence of canonical β-tubulin mutations within Ascaris, but alternative modes of anthelminthic resistance may emerge necessitating continued genetic scrutiny alongside monitoring of drug efficacy.
Topics: Tubulin; Animals; Benzimidazoles; Drug Resistance; Ascariasis; Mutation; Anthelmintics; Swine; Ascaris; Humans; Swine Diseases
PubMed: 38755679
DOI: 10.1186/s13071-024-06306-5 -
Parasites & Vectors May 2024Toxocara canis is considered one of the most neglected parasitic zoonoses and threatens the health of millions of people worldwide with a predilection for pediatric and...
BACKGROUND
Toxocara canis is considered one of the most neglected parasitic zoonoses and threatens the health of millions of people worldwide with a predilection for pediatric and adolescent populations in impoverished communities. Exploring the invasion and developmental mechanisms associated with T. canis infection in its definitive canine hosts will help to better control zoonotic toxocariasis.
METHODS
Proteomic changes in samples from the upper lobe of the left lung of Beagle puppies were systematically analyzed by quantitative proteomic technology of data-independent acquisition (DIA) at 96 h post-infection (hpi) with T. canis. Proteins with P-values < 0.05 and fold change > 1.5 or < 0.67 were considered proteins with differential abundance (PDAs).
RESULTS
A total of 28 downregulated PDAs and 407 upregulated PDAs were identified at 96 hpi, including RhoC, TM4SFs and LPCAT1, which could be associated with the maintenance and repair of lung homeostasis. GO annotation and KEGG pathway enrichment analyses of all identified proteins and PDAs revealed that many lung proteins have correlation to signal transduction, lipid metabolism and immune system.
CONCLUSIONS
The present study revealed lung proteomic alterations in Beagle dogs at the lung migration stage of T. canis infection and identified many PDAs of Beagle dog lung, which may play important roles in the pathogenesis of toxocariasis, warranting further experimental validation.
Topics: Animals; Dogs; Toxocariasis; Toxocara canis; Lung; Proteomics; Dog Diseases; Proteome
PubMed: 38725025
DOI: 10.1186/s13071-024-06302-9 -
The American Journal of Tropical... Jun 2024Soil-transmitted helminthiasis remains a notable health problem in developing countries. In 1990 in Shanghai, a city in eastern China, 47% of the population was...
Soil-transmitted helminthiasis remains a notable health problem in developing countries. In 1990 in Shanghai, a city in eastern China, 47% of the population was affected. Due to a series of comprehensive approaches, the prevalence decreased to 0.5% in 2009. We collected 10-year surveillance data to assess the epidemic situation of soil-transmitted helminth (STH) infections in Shanghai. Stool samples and questionnaires from participants were collected. The Kato-Katz technique was used to detect infections with Ascaris lumbricoides, hookworm (Ancylostoma duodenale and Necator americanus), and Trichuris trichiura. From 2014 to 2023, a total of 77,685 participants were screened for parasitic infections, and the overall prevalence of STH infections decreased from 0.1% to 0% in Shanghai. Of 77,685 participants, 25 (0.03%) were positive for intestinal helminths, with the most common parasite being A. lumbricoides (72.0%). Generally, elderly participants from rural areas with lower education levels were more likely to be infected with STHs. A total of 2,914 questionnaires were collected, and most respondents (72.6%) had good knowledge about the transmission routes of STHs. However, 12.3% of participants did not know the damage to health caused by STHs, and 19.3% had no idea of how to prevent infection. These data demonstrate the current state of STH infections in Shanghai. The results suggest that various comprehensive measures should be encouraged, continuously implemented, and strengthened accordingly so that STH elimination can be integrated into the Healthy China initiative by 2030.
Topics: Humans; China; Helminthiasis; Adult; Soil; Middle Aged; Male; Female; Adolescent; Child; Young Adult; Aged; Animals; Prevalence; Ascaris lumbricoides; Child, Preschool; Feces; Ascariasis; Intestinal Diseases, Parasitic; Trichuriasis; Surveys and Questionnaires; Hookworm Infections; Infant; Trichuris
PubMed: 38697072
DOI: 10.4269/ajtmh.23-0910 -
The American Journal of Tropical... Jun 2024Quantitative polymerase chain reaction (qPCR) is gaining recognition in soil-transmitted helminth (STH) diagnostics, especially for Strongyloides stercoralis and...
Quantitative polymerase chain reaction (qPCR) is gaining recognition in soil-transmitted helminth (STH) diagnostics, especially for Strongyloides stercoralis and differentiating hookworm species. However, sample preservation and DNA extraction may influence qPCR performance. We estimated STH prevalence and infection intensity by using qPCR in schoolchildren from Huambo, Uige, and Zaire, Angola, and compared its performance with that of the Kato-Katz technique (here termed Kato-Katz). Stool samples from 3,063 children (219 schools) were preserved in 96% ethanol and analyzed by qPCR, of which 2,974 children (215 schools) had corresponding Kato-Katz results. Cluster-adjusted prevalence and infection intensity estimates were calculated by qPCR and Kato-Katz, with cycle threshold values converted to eggs per gram for qPCR. Cohen's kappa statistic evaluated agreement between qPCR and Kato-Katz. DNA extraction and qPCR were repeated on 191 (of 278) samples that were initially qPCR negative but Kato-Katz positive, of which 112 (58.6%) became positive. Similar prevalence for Ascaris lumbricoides (37.5% versus 34.6%) and Trichuris trichiura (6.5% versus 6.1%) were found by qPCR and Kato-Katz, respectively, while qPCR detected a higher hookworm prevalence (11.9% versus 2.9%). The prevalence of moderate- or high-intensity infections was higher by Kato-Katz than by qPCR. Agreement between qPCR and Kato-Katz was very good for A. lumbricoides, moderate for T. trichiura, and fair for hookworm. Strongyloides stercoralis prevalence was 4.7% (municipality range, 0-14.3%), and no Ancylostoma ceylanicum was detected by qPCR. Despite suboptimal performance, presumably due to fixative choice, qPCR was fundamental in detecting S. stercoralis and excluding zoonotic A. ceylanicum. Further evaluations on sample fixatives and DNA extraction methods are needed to optimize and standardize the performance of qPCR.
Topics: Humans; Child; Angola; Animals; Prevalence; Feces; Soil; Male; Strongyloides stercoralis; Female; Helminthiasis; Real-Time Polymerase Chain Reaction; Adolescent; Ascaris lumbricoides; Strongyloidiasis; DNA, Helminth; Helminths; Parasite Egg Count; Trichuris
PubMed: 38688261
DOI: 10.4269/ajtmh.23-0821 -
Revista Alergia Mexico (Tecamachalco,... Feb 2024To compare the relative frequencies of immune cell populations in the peripheral blood according to infection status.
OBJECTIVE
To compare the relative frequencies of immune cell populations in the peripheral blood according to infection status.
METHODS
Peripheral blood samples were collected from participants infected (n = 35) and uninfected with (n=27) residing in different rural municipalities of Bolívar. Infection was diagnosed using two coprological examinations and the Kato-Katz technique. Immunophenotyping was performed using two panels of markers and staining in fresh blood. The flow cytometry reading was performed on a spectral cytometer (Northern Lights, Cytek, USA). The populations identified in the first panel (Figure 1) were T lymphocytes (CD45+ CD3+), CD4+ or CD8+, B lymphocytes (CD45+ SSClow CD3- CD19+), neutrophils (CD45+ SSChi CD3- CD16+), and eosinophils (CD45+ SSChi CD3- CD16low). Monocytes were identified in another panel (Figure 2): classical (CD14++ CD16 -), intermediate (CD14++ CD16+), and non-classical (CD14+ CD16++). Dendritic cells, including CD123 + + CD303 + (plasmacytoid), HLA-DR + + CD1c + (myeloid CD1c +), and CD14-CD141 + + (myeloid CD141 +), were also identified. The study received approval from the Ethics Committee of the University of Cartagena, and participants provided informed consent. Funding was provided by the Colombian Sistema General de Regalías under BPIN2020000100405 - BPIN2020000100364.
RESULTS
No significant differences were observed in age [mean cases: 35.69 (SD: 17.7) vs. controls: 37.04 (SD: 15.6) years] or sex (cases: 62.9% vs. controls: 74.1%) (Table 1). All infections were mild, with a median of 96 eggs (IQR, 48-216). A marginally significant difference was observed only in the percentage of neutrophils (45.37% in cases vs. 54.79% in controls, p=0.041) (Figure 3). Although the frequency of eosinophils was higher in the cases (8.1% vs. 6%), this difference was not significant (p=0.138) (Figure 3). No significant differences were observed in the populations of monocytes or dendritic cells between cases and controls (Figure 4).
CONCLUSION
Mild infection appears to affect the number of neutrophils in peripheral blood. The low infection intensity in the studied samples may explain the lack of a significant impact on other cellular populations.
Topics: Humans; Male; Female; Ascariasis; Adult; Adolescent; Animals; Young Adult; Rural Health; Child; Ascaris lumbricoides; Middle Aged; Colombia
PubMed: 38683086
DOI: 10.29262/ram.v71i1.1372 -
Revista Alergia Mexico (Tecamachalco,... Feb 2024To quantify the production of Th1/Th2/Th17 cytokines induced by Ascaris lumbricoides antigens in peripheral blood mononuclear cells (PBMCs) using a multiplex technique.
OBJECTIVE
To quantify the production of Th1/Th2/Th17 cytokines induced by Ascaris lumbricoides antigens in peripheral blood mononuclear cells (PBMCs) using a multiplex technique.
METHODS
PBMCs were cultured from individuals with mild A. lumbricoides infection (n = 20) and uninfected individuals (n = 21) and stimulated with A. lumbricoides extract (ExtAscaris), a mix of anti-CD2/CD3/CD28 (CDmix) as a positive control, and only medium (negative control). Cytokines in the supernatants were measured using the BD™ Cytometric Bead Array Human Th1/Th2/Th17 kit, to identify IFN-γ, TNF, IL-10, IL-6, IL-4, IL-2, and IL-17A. Readings were taken on a spectral cytometer (Northern Lights, Cytek, USA), and analysis was performed using R software with packages "tidyverse," "beadplexr," "flowCore," and "arsenal." Cytokine concentrations were calculated using a 5-parameter logistic curve. The t-test was used to compare cases and controls, and statistical significance was set at p < 0.05. The study was approved by the Ethics Committee of the University of Cartagena and the participants provided informed consent. This study was financially supported by the Colombian Sistema General de Regalías under the BPIN2020000100405 - BPIN2020000100364.
RESULTS
Efficient fluorescence intensity extraction for each cytokine was achieved using detection channel R8 and the "mclust" clustering model (Figure 1). No significant differences were found in the levels of the seven cytokines between cases and controls (Figure 2). Although the IFN-γ response to ExtAscaris was higher in cases than in controls (252.5 ng/mL vs. 173.1 ng/mL), the difference was not significant. IL-17A (detection limit: 18.9 pg/mL) was more detectable in cases than controls (5 cases, 23% vs. 2 controls, 9.5%). IL-4 was only detected in the supernatants from CDmix-stimulated cultures but not with the Ascaris extract (Figure 2).
CONCLUSIONS
The multiplex technique using spectral flow cytometry combined with open-source analysis proved applicable for quantifying cytokines induced by antigens in PBMCs. However, a more sensitive method is needed to evaluate IL-4 response in the context of ascariasis. The results did not reveal significant differences in cytokine production between cases and controls for the evaluated stimuli.
Topics: Humans; Cytokines; Flow Cytometry; Ascariasis; Male; Female; Adult; Animals; Leukocytes, Mononuclear; Ascaris lumbricoides; Young Adult; Middle Aged; Adolescent; Antigens, Helminth
PubMed: 38683082
DOI: 10.29262/ram.v71i1.1365 -
Revista Alergia Mexico (Tecamachalco,... Feb 2024To evaluate the IgE reactivity of sera in patients suffering from type 1 diabetes (T1D), lupus nephritis (LN) and juvenile idiopathic arthritis (JIA) against a molecule...
OBJECTIVE
To evaluate the IgE reactivity of sera in patients suffering from type 1 diabetes (T1D), lupus nephritis (LN) and juvenile idiopathic arthritis (JIA) against a molecule constructed from T epitopes of allergens.
METHODS
We designed and expressed a synthetic multi-epítope protein named MP1 from A. lumbricoides and house dust mites allergens. By indirect ELISA, we evaluated IgE-reactivity to MP1 and to the whole-body extract of in 45 sera from Colombian Caribbean patients with lupus nephritis (LN; n=25), type 1 diabetes (T1D; n=10) and Juvenil idiopathic arthritis (JIA; n=10). Individuals with poly autoimmunity were excluded. All patients were referred to the study by their specialist doctor.
RESULTS
IgE to whole-body extract of showed the following median concentrations.
UNLABELLED
484.2 ng/ml (IQR: 203.4) in JIA patients, 325.6 ng/ml (IQR: 179.3) in individuals with LN, and 424.7 ng/ml (IQR: 80.1) in the T1D group. On the other hand, IgE-reactivity to MP1 individual with LN, and 148.8 ng/ml (IQR: 102.1) in the T1D group. Although no statistical differences were observed between patient groups, the IgE to MP1 in all patients (n: 45) (IgE median: 134.2 ng/ml; IQR: 100) were significantly less compared to Ascaris extract (IgE median: 380.7 ng/ml; IQR: 175.8); ( 0.732; 1.034x10).
CONCLUSIONS
These preliminary results suggest that MP1 showed antigenic properties with low IgE- reactivity, compared to extracted in individuals with autoimmune diseases. Further studies are needed to understand better the immune response induced by this molecule.
Topics: Humans; Animals; Ascaris lumbricoides; Immunoglobulin E; Allergens; Female; Male; Autoimmune Diseases; Adolescent; Child; Epitopes, T-Lymphocyte; Adult
PubMed: 38683071
DOI: 10.29262/ram.v71i1.1366 -
Infectious Diseases in Obstetrics and... 2024Toxocariasis is an important health problem caused by the parasitic species () and (). Prevalence of toxocariasis in pregnant women as a vulnerable population is... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Toxocariasis is an important health problem caused by the parasitic species () and (). Prevalence of toxocariasis in pregnant women as a vulnerable population is doubly important, and the aim of this study is to estimate the overall prevalence of toxocariasis infection in pregnant women according to the available reports.
METHODS
The present study followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) checklists. A systematic search was carried out in international scientific databases (Google Scholar, Web of Science, ScienceDirect, Scopus, and PubMed) between 1990 and 2023. The overall prevalence of parasitic infection was estimated with a random-effects model. All analyses (overall prevalence, heterogeneity, publication bias, and sensitivity analysis) were performed with comprehensive meta-analysis (V2.2, Bio stat) software.
RESULTS
Amid the final eleven included studies, based on the random-effects model, the estimation of the pooled prevalence of spp. was 20.8% (95% CI, 9.8-38.7%). The association between the risk factors of toxocariasis and the prevalence of the disease was not statistically significant.
CONCLUSIONS
In the present study, significant prevalence was reported; however, considering the limited number of studies, it seems that the actual prevalence of the disease is higher. Therefore, it seems necessary to monitor this health problem in pregnant women.
Topics: Humans; Female; Pregnancy; Toxocariasis; Animals; Toxocara; Seroepidemiologic Studies; Pregnancy Complications, Parasitic; Prevalence; Toxocara canis
PubMed: 38682081
DOI: 10.1155/2024/1943353 -
Experimental Parasitology Jun 2024Toxocara is a genus of nematodes, which infects a variety of hosts, principally dogs and cats, with potential zoonotic risks to humans. Toxocara spp. larvae are capable... (Comparative Study)
Comparative Study
Toxocara is a genus of nematodes, which infects a variety of hosts, principally dogs and cats, with potential zoonotic risks to humans. Toxocara spp. larvae are capable of migrating throughout the host tissues, eliciting eosinophilic and granulomatous reactions, while surviving for extended periods of time, unchanged, in the host. It is postulated that larvae are capable of altering the host's immune response through the release of excretory-secretory products, containing both proteins and extracellular vesicles (EVs). The study of EVs has increased exponentially in recent years, largely due to their potential use as a diagnostic tool, and in molecular therapy. To this end, there have been multiple isolation methods described for the study of EVs. Here, we use nanoparticle tracking to compare the yield, size distribution, and % labelling of EV samples acquired through various reported methods, from larval cultures of Toxocara canis and T. cati containing Toxocara excretory-secretory products (TES). The methods tested include ultracentrifugation, polymer precipitation, magnetic immunoprecipitation, size exclusion chromatography, and ultrafiltration. Based on these findings, ultrafiltration produces the best results in terms of yield, expected particle size, and % labelling of sample. Transmission electron microscopy confirmed the presence of EVs with characteristic cup-shaped morphology. These findings can serve as a guide for those investigating EVs, particularly those released from multicellular organisms, such as helminths, for which few comparative analyses have been performed.
Topics: Animals; Toxocara; Toxocara canis; Microscopy, Electron, Transmission; Ultracentrifugation; Chromatography, Gel; Exosomes; Extracellular Vesicles; Dogs; Larva; Immunoprecipitation; Toxocariasis; Cats; Nanoparticles; Particle Size; Helminth Proteins
PubMed: 38679126
DOI: 10.1016/j.exppara.2024.108765 -
Acta Tropica Jul 2024Toxocara canis can produce the "larva migrans" syndrome in humans, and in puppies, it can cause severe digestive disorders. The most used treatments are based on...
Toxocara canis can produce the "larva migrans" syndrome in humans, and in puppies, it can cause severe digestive disorders. The most used treatments are based on anthelmintics, although there are reports of anthelmintic (AH) resistance. The Yucatan Peninsula has a great variety of plant species whose AH properties are still unknown. The objective of this study was to evaluate the in vitro AH activity of ethanolic (EE), methanolic (ME) and aqueous (AE) extracts from the leaves of five native plant species of the Yucatan Peninsula on T. canis eggs of dogs from Merida, Yucatan. As part of a screening, the EE of the plants Alseis yucatanensis, Calea jamaicensis, Cameraria latifolia, Macrocepis diademata, and Parathesis cubana were evaluated at doses of 2400 and 3600 μg/ml. The EE and AE of A. yucatanensis and M. diademata presented high percentages (≥ 91.3%) of inhibition of the larval development of T. canis after six days of exposure. The lowest LC and LC was presented by the ME from A. yucatanensis (255.5 and 629.06 µg/ml, respectively) and the ME from M. diademata (222.4 and 636.5 µg/ml, respectively), and the AE from A. yucatanenesis (LC of 535.9 µg/ml). Chemical profiling of the most potent AH extract (Alseis yucatanensis) was carried out by LC-UV-HRMS. Data from the ME and AE from this plant indicated the presence of the known glucosylngoumiensine, kaempferol 3,7-diglucosyde, uvaol, linoleic acid and linolenic acid together with unknown alkaloids. The EE, ME and AE from leaves of M. diademata and A. yucatanensis could be developed as natural alternatives to control T. canis.
Topics: Animals; Plant Extracts; Anthelmintics; Toxocara canis; Dogs; Plant Leaves; Mexico; Larva
PubMed: 38663537
DOI: 10.1016/j.actatropica.2024.107214