Frontiers in parasitology最新文献

{"title":"Early immune and host cell responses to <i>Cryptosporidium</i> infection.","authors":"Jan R Mead","doi":"10.3389/fpara.2023.1113950","DOIUrl":"10.3389/fpara.2023.1113950","url":null,"abstract":"<p><p><i>Cryptosporidium</i> spp. are opportunistic protozoan parasites that infect epithelial cells of the small intestine and cause diarrheal illness in both immunocompetent and immunodeficient individuals. These infections may be more severe in immunocompromised individuals and young children, especially in children under 2 in developing countries. The parasite has a global distribution and is an important cause of childhood diarrhea where it may result in cognitive impairment and growth deficits. Current therapies are limited with nitazoxanide being the only FDA-approved drug. However, it is not efficacious in immunocompromised patients. Additionally, there are no vaccines for cryptosporidiosis available. While acquired immunity is needed to clear <i>Cryptosporidium</i> parasites completely, innate immunity and early responses to infection are important in keeping the infection in check so that adaptive responses have time to develop. Infection is localized to the epithelial cells of the gut. Therefore, host cell defenses are important in the early response to infection and may be triggered through toll receptors or inflammasomes which induce a number of signal pathways, interferons, cytokines, and other immune mediators. Chemokines and chemokine receptors are upregulated which recruit immune cells such neutrophils, NK cells, and macrophages to the infection site to help in host cell defense as well as dendritic cells that are an important bridge between innate and adaptive responses. This review will focus on the host cell responses and the immune responses that are important in the early stages of infection.</p>","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":"2 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10269812/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9671941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of molecular surveillance methods to assess changes in the population genetics of <i>Plasmodium falciparum</i> in high transmission.","authors":"Anita Ghansah, Kathryn E Tiedje, Dionne C Argyropoulos, Christiana O Onwona, Samantha L Deed, Frédéric Labbé, Abraham R Oduro, Kwadwo A Koram, Mercedes Pascual, Karen P Day","doi":"10.3389/fpara.2023.1067966","DOIUrl":"10.3389/fpara.2023.1067966","url":null,"abstract":"<p><p>A major motivation for developing molecular methods for malaria surveillance is to measure the impact of control interventions on the population genetics of <i>Plasmodium falciparum</i> as a potential marker of progress towards elimination. Here we assess three established methods (i) single nucleotide polymorphism (SNP) barcoding (panel of 24-biallelic loci), (ii) microsatellite genotyping (panel of 12-multiallelic loci), and (iii) <i>var</i>coding (fingerprinting <i>var</i> gene diversity, akin to microhaplotyping) to identify changes in parasite population genetics in response to a short-term indoor residual spraying (IRS) intervention. Typical of high seasonal transmission in Africa, multiclonal infections were found in 82.3% (median 3; range 1-18) and 57.8% (median 2; range 1-12) of asymptomatic individuals pre- and post-IRS, respectively, in Bongo District, Ghana. Since directly phasing multilocus haplotypes for population genetic analysis is not possible for biallelic SNPs and microsatellites, we chose ~200 low-complexity infections biased to single and double clone infections for analysis. Each genotyping method presented a different pattern of change in diversity and population structure as a consequence of variability in usable data and the relative polymorphism of the molecular markers (i.e., SNPs < microsatellites < <i>var</i>). <i>Var</i>coding and microsatellite genotyping showed the overall failure of the IRS intervention to significantly change the population structure from pre-IRS characteristics (i.e., many diverse genomes of low genetic similarity). The 24-SNP barcode provided limited information for analysis, largely due to the biallelic nature of SNPs leading to a high proportion of double-allele calls and a view of more isolate relatedness compared to microsatellites and <i>var</i>coding. Relative performance, suitability, and cost-effectiveness of the methods relevant to sample size and local malaria elimination in high-transmission endemic areas are discussed.</p>","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10686283/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47093572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulatory void for vaccines targeting eukaryotic parasites of farmed and domestic animals and fish.","authors":"Peter Holdsworth, Maggie Fisher","doi":"10.3389/fpara.2022.1073801","DOIUrl":"10.3389/fpara.2022.1073801","url":null,"abstract":"","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":"1 1","pages":"1073801"},"PeriodicalIF":0.0,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732125/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42048089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The immunology of parasite infections: Grand challenges.","authors":"Sheila Donnelly","doi":"10.3389/fpara.2022.1069205","DOIUrl":"10.3389/fpara.2022.1069205","url":null,"abstract":"","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"1069205"},"PeriodicalIF":0.0,"publicationDate":"2022-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732110/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44550980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular subtyping of <i>Blastocystis</i> sp. detected in patients at a large tertiary referral hospital in Lusaka, Zambia.","authors":"Gilbert Munsaka, Kyoko Hayashida, Benjamin Mubemba, Edgar Simulundu, Namwiinga Mulunda, Ruth Pule, Sandie Sianongo, Marina Makuluni, Walter Muleya, Katendi Changula, Simbarashe Chitanga, Mable Mutengo","doi":"10.3389/fpara.2022.1033485","DOIUrl":"10.3389/fpara.2022.1033485","url":null,"abstract":"<p><strong>Background: </strong><i>Blastocystis</i> sp. is a common enteric eukaryote of humans whose pathogenicity is still debatable. However, a number of reported <i>Blastocystis</i> colonization associated with enteric disease exist. In Zambia, presence of the pathogen has previously been reported in children. However, the molecular epidemiology of <i>Blastocystis</i> colonization remains unclarified in Zambia.</p><p><strong>Methods and results: </strong>Archived stool samples submitted for routine parasitological diagnosis at Zambia's largest tertiary referral hospital positive for <i>Blastocystis</i> sp. by microscopic examination were selected for the study. Subtyping of the <i>Blastocystis</i> was done based on polymerase chain reactions (PCR) amplification, sequencing and subsequent phylogenetic analysis of the 18S small subunit (<i>SSU</i>) rDNA gene. Four subtypes, ST1 (allele 4), ST2 (allele 12), ST3 (allele 34, 36, 37, 38, 39) and ST6 (allele 122), were identified by molecular procedures in the study, with some Zambian sequences showing close relationships with those detected in non-human primates and common rats.</p><p><strong>Conclusions: </strong>The study revealed the circulation of multiple <i>Blastocystis</i> subtypes ST1, 20% (9/45), ST2, 15% (7/45), ST3 24.4% (11/45), and ST6, 2.2% (1/45) in the study population. The close clustering of some Zambian sequences with those detected from animals suggests the possibility of the presence of both anthroponotic and zoonotic transmission cycles in the country. Further studies in animal populations are recommended for a better understanding of the epidemiology of <i>Blastocystis</i> and for implementation of effective evidence-based control strategies.</p>","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"1033485"},"PeriodicalIF":0.0,"publicationDate":"2022-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11731786/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43119657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grand challenges in parasite epidemiology and ecology.","authors":"Alyssa E Barry","doi":"10.3389/fpara.2022.1034819","DOIUrl":"10.3389/fpara.2022.1034819","url":null,"abstract":"","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"1034819"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11731595/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42915692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The FLOTAC basic technique as a new extraction method for root-knot nematodes (<i>Meloidogyne</i> spp.) from soil and roots.","authors":"Alberto Troccoli, Giada d'Errico, Trifone D'Addabbo, Nicola Sasanelli, Antonio Bosco, Maria P Maurelli, Laura Rinaldi, Giuseppe Cringoli","doi":"10.3389/fpara.2022.1000673","DOIUrl":"10.3389/fpara.2022.1000673","url":null,"abstract":"<p><p>FLOTAC Techniques have been widely acknowledged as an effective method for the extraction of human and animal parasites. The present study is the first application of FLOTAC basic technique (FBT) for the extraction of phytoparasitic nematodes from soil and infested plant roots. Eggs and second stage juveniles (J₂) of the root-knot nematode <i>Meloidogyne incognita</i> were extracted from infested soil and tomato roots either by FBT and conventional nematode extraction methods, such as centrifugal flotation and root maceration techniques, respectively. The number of <i>M. incognita</i> J₂ and eggs extracted from soil by FBT was always significantly higher compared to the extraction with the centrifugal flotation method, averaging 277 <i>vs</i> 35 eggs and J₂ mL^-1 soil. Conversely, no significant differences were observed between FBT and the root maceration technique in the extraction of eggs and J₂ from tomato roots. Results demonstrated that FBT can be highly effective also for the extraction of phytoparasitic nematodes. Due to its accuracy and sensitivity, FBT seems particularly suitable for nematode surveys in wide geographical areas, where an accurate and rapid detection of present phytoparasitic nematofauna is required.</p>","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"1000673"},"PeriodicalIF":0.0,"publicationDate":"2022-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732173/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47478182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunomodulatory and biological properties of helminth-derived small molecules: Potential applications in diagnostics and therapeutics.","authors":"Karma Yeshi, Roland Ruscher, Alex Loukas, Phurpa Wangchuk","doi":"10.3389/fpara.2022.984152","DOIUrl":"10.3389/fpara.2022.984152","url":null,"abstract":"<p><p>Parasitic helminths secrete and excrete a vast array of molecules known to help skew or suppress the host's immune response, thereby establishing a niche for sustained parasite maintenance. Indeed, the immunomodulatory potency of helminths is attributed mainly to excretory/secretory products (ESPs). The ESPs of helminths and the identified small molecules (SM) are reported to have diverse biological and pharmacological properties. The available literature reports only limited metabolites, and the identity of many metabolites remains unknown due to limitations in the identification protocols and helminth-specific compound libraries. Many metabolites are known to be involved in host-parasite interactions and pathogenicity. For example, fatty acids (e.g., stearic acid) detected in the infective stages of helminths are known to have a role in host interaction through facilitating successful penetration and migration inside the host. Moreover, excreted/secreted SM detected in helminth species are found to possess various biological properties, including anti-inflammatory activities, suggesting their potential in developing immunomodulatory drugs. For example, helminths-derived somatic tissue extracts and whole crude ESPs showed anti-inflammatory properties by inhibiting the secretion of proinflammatory cytokines from human peripheral blood mononuclear cells and suppressing the pathology in chemically-induced experimental mice model of colitis. Unlike bigger molecules like proteins, SM are ideal candidates for drug development since they are small structures, malleable, and lack immunogenicity. Future studies should strive toward identifying unknown SM and isolating the under-explored niche of helminth metabolites using the latest metabolomics technologies and associated software, which hold potential keys for finding new diagnostics and novel therapeutics.</p>","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"984152"},"PeriodicalIF":0.0,"publicationDate":"2022-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11731824/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47821984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parasite OMICS, the grand challenges ahead.","authors":"Makedonka Mitreva","doi":"10.3389/fpara.2022.995302","DOIUrl":"10.3389/fpara.2022.995302","url":null,"abstract":"","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"995302"},"PeriodicalIF":0.0,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732041/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42186896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Cellular Parasitology: The Decades and Challenges Ahead.","authors":"Mark C Field","doi":"10.3389/fpara.2022.963515","DOIUrl":"10.3389/fpara.2022.963515","url":null,"abstract":"","PeriodicalId":73098,"journal":{"name":"Frontiers in parasitology","volume":" ","pages":"963515"},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11732077/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46313571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}