The immunobiology of myiasis infections--whatever happened to vaccination?
- Sandeman, Mark, Bowles, Vern, Colwell, Doug
- Authors: Sandeman, Mark , Bowles, Vern , Colwell, Doug
- Date: 2014
- Type: Text , Journal article
- Relation: Parasite immunology Vol. 36, no. 11 (2014), p. 605-615
- Full Text:
- Reviewed:
- Description: The current state of myiasis vaccine technologies are reviewed mainly in the primary research genera of Lucilia and Hypoderma. The importance of myiasis flies as primary causes of morbidity and mortality in agricultural species and man has not diminished despite the existence of good control strategies. However, the development of vaccines against myiasis infections has been relatively quiescent for more than 10 years despite the rapid development of genomic and proteomic analysis and of skills in data interpretation. The value of vaccine research in an era of chemical primacy is analysed. In fact, recent findings of drug resistance and the impact of animal welfare concerns should mean a renewed interest in alternative controls. The reasons that this has not been true to date are explored and new possibilities discussed.
- Authors: Sandeman, Mark , Bowles, Vern , Colwell, Doug
- Date: 2014
- Type: Text , Journal article
- Relation: Parasite immunology Vol. 36, no. 11 (2014), p. 605-615
- Full Text:
- Reviewed:
- Description: The current state of myiasis vaccine technologies are reviewed mainly in the primary research genera of Lucilia and Hypoderma. The importance of myiasis flies as primary causes of morbidity and mortality in agricultural species and man has not diminished despite the existence of good control strategies. However, the development of vaccines against myiasis infections has been relatively quiescent for more than 10 years despite the rapid development of genomic and proteomic analysis and of skills in data interpretation. The value of vaccine research in an era of chemical primacy is analysed. In fact, recent findings of drug resistance and the impact of animal welfare concerns should mean a renewed interest in alternative controls. The reasons that this has not been true to date are explored and new possibilities discussed.
Changes in the ghrelin hormone pathway maybe part of an unusual gastric system in monotremes
- He, Chuan, Tsend-Ayush, Enkhjargal, Myers, Mark, Forbes, Briony, Grützner, Frank
- Authors: He, Chuan , Tsend-Ayush, Enkhjargal , Myers, Mark , Forbes, Briony , Grützner, Frank
- Date: 2013
- Type: Text , Journal article
- Relation: General and Comparative Endocrinology Vol. 191, no. (2013), p. 74-82
- Full Text:
- Reviewed:
- Description: Ghrelin is a growth hormone (GH)-releasing and appetite-regulating peptide predominately released from the stomach. Ghrelin is evolutionarily highly conserved and known to have a wide range of functions including the regulation of metabolism by maintaining an insulin-glucose balance. The peptide is produced as a single proprotein, which is later proteolytically cleaved. Ghrelin exerts its biological function after O-n-octanoylation at residue serine 3, which is catalyzed by ghrelin O-acyl transferase (GOAT) and allows binding to the growth hormone secretagogue receptor (GHS-R 1a). Genes involved in the ghrelin pathway have been identified in a broad range of vertebrate species, however, little is known about this pathway in the basal mammalian lineage of monotremes (platypus and echidna). Monotremes are particularly interesting in this context, as they have undergone massive changes in stomach anatomy and physiology, accompanied by a striking loss of genes involved in gastric function. In this study, we investigated genes in the ghrelin pathway in monotremes. Using degenerate PCR, database searches and synteny analysis we found that genes encoding ghrelin and GOAT are missing in the platypus genome, whilst, as has been reported in other species, the GHSR is present and expressed in brain, pancreas, kidney, intestine, heart and stomach. This is the first report suggesting the loss of ghrelin in a mammal. The loss of this gene may be related to changes to the platypus digestive system and raises questions about the control of blood glucose levels and insulin response in monotreme mammals. In addition, the conservation of the ghrelin receptor gene in platypus indicates that another ligand(s) maybe acting via this receptor in monotremes. © 2013 Elsevier Inc.
- Description: 2003011207
- Authors: He, Chuan , Tsend-Ayush, Enkhjargal , Myers, Mark , Forbes, Briony , Grützner, Frank
- Date: 2013
- Type: Text , Journal article
- Relation: General and Comparative Endocrinology Vol. 191, no. (2013), p. 74-82
- Full Text:
- Reviewed:
- Description: Ghrelin is a growth hormone (GH)-releasing and appetite-regulating peptide predominately released from the stomach. Ghrelin is evolutionarily highly conserved and known to have a wide range of functions including the regulation of metabolism by maintaining an insulin-glucose balance. The peptide is produced as a single proprotein, which is later proteolytically cleaved. Ghrelin exerts its biological function after O-n-octanoylation at residue serine 3, which is catalyzed by ghrelin O-acyl transferase (GOAT) and allows binding to the growth hormone secretagogue receptor (GHS-R 1a). Genes involved in the ghrelin pathway have been identified in a broad range of vertebrate species, however, little is known about this pathway in the basal mammalian lineage of monotremes (platypus and echidna). Monotremes are particularly interesting in this context, as they have undergone massive changes in stomach anatomy and physiology, accompanied by a striking loss of genes involved in gastric function. In this study, we investigated genes in the ghrelin pathway in monotremes. Using degenerate PCR, database searches and synteny analysis we found that genes encoding ghrelin and GOAT are missing in the platypus genome, whilst, as has been reported in other species, the GHSR is present and expressed in brain, pancreas, kidney, intestine, heart and stomach. This is the first report suggesting the loss of ghrelin in a mammal. The loss of this gene may be related to changes to the platypus digestive system and raises questions about the control of blood glucose levels and insulin response in monotreme mammals. In addition, the conservation of the ghrelin receptor gene in platypus indicates that another ligand(s) maybe acting via this receptor in monotremes. © 2013 Elsevier Inc.
- Description: 2003011207
Liver fluke vaccines : Vaccination against Fasciolosis by a multivalent vaccine of recombinant stage-specific antigens
- Jayaraj, Ramamoorthi, Piedrafita, David, Dynon, Kemperley, Grams, Rudi, Spithill, Terry, Smooker, Peter
- Authors: Jayaraj, Ramamoorthi , Piedrafita, David , Dynon, Kemperley , Grams, Rudi , Spithill, Terry , Smooker, Peter
- Date: 2010
- Type: Text , Journal article
- Relation: Procedia in Vaccinology Vol. 2, no. 1 (Special issue) (2010), p. 82-85
- Full Text:
- Reviewed:
- Description: Fasciola's excretory-secretory material comprises chiefly cathepsin B and cathepsin L. These cysteine proteases are proposed as major mediators of parasitism, and are considered targets for vaccination. In order to assess the vaccine efficacy of these enzymes, single and multivalent recombinant protein vaccinations of adult-stage F. hepatica cathepsin L5, metacercarial-stage F. gigantica cathepsin L1 g and juvenile-stage F. hepatica cathepsin B were analysed in rats against F. hepatica challenge infection. The protective efficacy of anti-fluke vaccines was evaluated in terms of parasitological parameters (recovered fluke burden, fluke body size and wet weight) and pathological changes (liver damage score) in rats. The rats vaccinated with recombinant proteins were shown to have significantly fewer and smaller flukes than the control rats. A maximum protection of 83% was seen in the group vaccinated with a combination of cathepsin B and cathepsin L5.
- Authors: Jayaraj, Ramamoorthi , Piedrafita, David , Dynon, Kemperley , Grams, Rudi , Spithill, Terry , Smooker, Peter
- Date: 2010
- Type: Text , Journal article
- Relation: Procedia in Vaccinology Vol. 2, no. 1 (Special issue) (2010), p. 82-85
- Full Text:
- Reviewed:
- Description: Fasciola's excretory-secretory material comprises chiefly cathepsin B and cathepsin L. These cysteine proteases are proposed as major mediators of parasitism, and are considered targets for vaccination. In order to assess the vaccine efficacy of these enzymes, single and multivalent recombinant protein vaccinations of adult-stage F. hepatica cathepsin L5, metacercarial-stage F. gigantica cathepsin L1 g and juvenile-stage F. hepatica cathepsin B were analysed in rats against F. hepatica challenge infection. The protective efficacy of anti-fluke vaccines was evaluated in terms of parasitological parameters (recovered fluke burden, fluke body size and wet weight) and pathological changes (liver damage score) in rats. The rats vaccinated with recombinant proteins were shown to have significantly fewer and smaller flukes than the control rats. A maximum protection of 83% was seen in the group vaccinated with a combination of cathepsin B and cathepsin L5.
Metabolic profiling and in vitro assessment of anthelmintic fractions of Picria fel-terrae Lour
- Kumarasingha, Rasika, Karpe, Avinash, Preston, Sarah, Yeo, Tiong-Chia, Lim, Diana, Tu, Chu-Lee, Luu, Jennii, Simpson, Kaylene, Shaw, Jillian, Gasser, Robin, Beale, David, Morrison, Paul, Palombo, Enzo, Boag, Peter
- Authors: Kumarasingha, Rasika , Karpe, Avinash , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Luu, Jennii , Simpson, Kaylene , Shaw, Jillian , Gasser, Robin , Beale, David , Morrison, Paul , Palombo, Enzo , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: International Journal for Parasitology: Drugs and Drug Resistance Vol. 6, no. 3 (2016), p. 171-178
- Full Text:
- Reviewed:
- Description: Anthelmintic resistance is widespread in gastrointestinal nematode populations, such that there is a consistent need to search for new anthelmintics. However, the cost of screening for new compounds is high and has a very low success rate. Using the knowledge of traditional healers from Borneo Rainforests (Sarawak, Malaysia), we have previously shown that some traditional medicinal plants are a rich source of potential new anthelmintic drug candidates. In this study, Picria fel-terrae Lour. plant extract, which has previously shown promising anthelmintic activities, was fractionated via the use of a solid phase extraction cartridge and each isolated fraction was then tested on free-living nematode Caenorhabditis elegans and the parasitic nematode Haemonchus contortus. We found that a single fraction was enriched for nematocidal activity, killing ≥90% of C. elegans adults and inhibiting the motility of exsheathed L3 of H. contortus, while having minimal cytotoxic activity in mammalian cell culture. Metabolic profiling and chemometric analysis of the effective fraction indicated medium chained fatty acids and phenolic acids were highly represented. Image 1 •Chemical fractionation of Picria fel-terrae Lour. plant extract.•Anthelmintic activity against Caenorhabditis elegans and Haemonchus contortus.•Metabolic profiling and chemometric analysis of active fraction.•Active fraction has minimal mammalian cytotoxicity.
- Authors: Kumarasingha, Rasika , Karpe, Avinash , Preston, Sarah , Yeo, Tiong-Chia , Lim, Diana , Tu, Chu-Lee , Luu, Jennii , Simpson, Kaylene , Shaw, Jillian , Gasser, Robin , Beale, David , Morrison, Paul , Palombo, Enzo , Boag, Peter
- Date: 2016
- Type: Text , Journal article
- Relation: International Journal for Parasitology: Drugs and Drug Resistance Vol. 6, no. 3 (2016), p. 171-178
- Full Text:
- Reviewed:
- Description: Anthelmintic resistance is widespread in gastrointestinal nematode populations, such that there is a consistent need to search for new anthelmintics. However, the cost of screening for new compounds is high and has a very low success rate. Using the knowledge of traditional healers from Borneo Rainforests (Sarawak, Malaysia), we have previously shown that some traditional medicinal plants are a rich source of potential new anthelmintic drug candidates. In this study, Picria fel-terrae Lour. plant extract, which has previously shown promising anthelmintic activities, was fractionated via the use of a solid phase extraction cartridge and each isolated fraction was then tested on free-living nematode Caenorhabditis elegans and the parasitic nematode Haemonchus contortus. We found that a single fraction was enriched for nematocidal activity, killing ≥90% of C. elegans adults and inhibiting the motility of exsheathed L3 of H. contortus, while having minimal cytotoxic activity in mammalian cell culture. Metabolic profiling and chemometric analysis of the effective fraction indicated medium chained fatty acids and phenolic acids were highly represented. Image 1 •Chemical fractionation of Picria fel-terrae Lour. plant extract.•Anthelmintic activity against Caenorhabditis elegans and Haemonchus contortus.•Metabolic profiling and chemometric analysis of active fraction.•Active fraction has minimal mammalian cytotoxicity.
The forgotten exotic tapeworms : a review of uncommon zoonotic cyclophyllidea
- Sapp, Sarah, Bradbury, Richard
- Authors: Sapp, Sarah , Bradbury, Richard
- Date: 2020
- Type: Text , Journal article , Review
- Relation: Parasitology Vol. 147, no. 5 (2020), p. 533-558
- Full Text:
- Reviewed:
- Description: As training in helminthology has declined in the medical microbiology curriculum, many rare species of zoonotic cestodes have fallen into obscurity. Even among specialist practitioners, knowledge of human intestinal cestode infections is often limited to three genera, Taenia, Hymenolepis and Dibothriocephalus. However, five genera of uncommonly encountered zoonotic Cyclophyllidea (Bertiella, Dipylidium, Raillietina, Inermicapsifer and Mesocestoides) may also cause patent intestinal infections in humans worldwide. Due to the limited availability of summarized and taxonomically accurate data, such cases may present a diagnostic dilemma to clinicians and laboratories alike. In this review, historical literature on these cestodes is synthesized and knowledge gaps are highlighted. Clinically relevant taxonomy, nomenclature, life cycles, morphology of human-infecting species are discussed and clarified, along with the clinical presentation, diagnostic features and molecular advances, where available. Due to the limited awareness of these agents and identifying features, it is difficult to assess the true incidence of these 'forgotten' cestodiases as clinical misidentifications are likely to occur. Also, the taxonomic status of many of the human-infecting species of these tapeworms is unclear, hampering accurate species identification. Further studies combining molecular data and morphological observations are necessary to resolve these long-standing taxonomic issues and to elucidate other unknown aspects of transmission and ecology. Copyright © The Author(s), US Government, 2020.
- Authors: Sapp, Sarah , Bradbury, Richard
- Date: 2020
- Type: Text , Journal article , Review
- Relation: Parasitology Vol. 147, no. 5 (2020), p. 533-558
- Full Text:
- Reviewed:
- Description: As training in helminthology has declined in the medical microbiology curriculum, many rare species of zoonotic cestodes have fallen into obscurity. Even among specialist practitioners, knowledge of human intestinal cestode infections is often limited to three genera, Taenia, Hymenolepis and Dibothriocephalus. However, five genera of uncommonly encountered zoonotic Cyclophyllidea (Bertiella, Dipylidium, Raillietina, Inermicapsifer and Mesocestoides) may also cause patent intestinal infections in humans worldwide. Due to the limited availability of summarized and taxonomically accurate data, such cases may present a diagnostic dilemma to clinicians and laboratories alike. In this review, historical literature on these cestodes is synthesized and knowledge gaps are highlighted. Clinically relevant taxonomy, nomenclature, life cycles, morphology of human-infecting species are discussed and clarified, along with the clinical presentation, diagnostic features and molecular advances, where available. Due to the limited awareness of these agents and identifying features, it is difficult to assess the true incidence of these 'forgotten' cestodiases as clinical misidentifications are likely to occur. Also, the taxonomic status of many of the human-infecting species of these tapeworms is unclear, hampering accurate species identification. Further studies combining molecular data and morphological observations are necessary to resolve these long-standing taxonomic issues and to elucidate other unknown aspects of transmission and ecology. Copyright © The Author(s), US Government, 2020.
Hc-daf-2 encodes an insulin-like receptor kinase in the barber's pole worm, Haemonchus contortus, and restores partial dauer regulation
- Li, Facai, Lok, James, Gasser, Robin, Korhonen, Pasi, Sandeman, Mark, Shi, Deshi, Zhou, Rui, Li, Xiangrui, Zhou, Yanqin, Zhao, Junlong, Hu, Min
- Authors: Li, Facai , Lok, James , Gasser, Robin , Korhonen, Pasi , Sandeman, Mark , Shi, Deshi , Zhou, Rui , Li, Xiangrui , Zhou, Yanqin , Zhao, Junlong , Hu, Min
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal for Parasitology Vol. 44, no. 7 (2014), p. 485-496
- Full Text:
- Reviewed:
- Description: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/. Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism. © 2014 Australian Society for Parasitology Inc.
- Authors: Li, Facai , Lok, James , Gasser, Robin , Korhonen, Pasi , Sandeman, Mark , Shi, Deshi , Zhou, Rui , Li, Xiangrui , Zhou, Yanqin , Zhao, Junlong , Hu, Min
- Date: 2014
- Type: Text , Journal article
- Relation: International Journal for Parasitology Vol. 44, no. 7 (2014), p. 485-496
- Full Text:
- Reviewed:
- Description: Infective L3s (iL3s) of parasitic nematodes share common behavioural, morphological and developmental characteristics with the developmentally arrested (dauer) larvae of the free-living nematode Caenorhabditis elegans. It is proposed that similar molecular mechanisms regulate entry into or exit from the dauer stage in C. elegans, and the transition from free-living to parasitic forms of parasitic nematodes. In C. elegans, one of the key factors regulating the dauer transition is the insulin-like receptor (designated Ce-DAF-2) encoded by the gene Ce-daf-2. However, nothing is known about DAF-2 homologues in most parasitic nematodes. Here, using a PCR-based approach, we identified and characterised a gene (Hc-daf-2) and its inferred product (Hc-DAF-2) in Haemonchus contortus (a socioeconomically important parasitic nematode of ruminants). The sequence of Hc-DAF-2 displays significant sequence homology to insulin receptors (IR) in both vertebrates and invertebrates, and contains conserved structural domains. A sequence encoding an important proteolytic motif (RKRR) identified in the predicted peptide sequence of Hc-DAF-2 is consistent with that of the human IR, suggesting that it is involved in the formation of the IR complex. The Hc-daf-2 gene was transcribed in all life stages of H. contortus, with a significant up-regulation in the iL3 compared with other stages. To compare patterns of expression between Hc-daf-2 and Ce-daf-2, reporter constructs fusing the Ce-daf-2 or Hc-daf-2 promoter to sequence encoding GFP were microinjected into the N2 strain of C. elegans, and transgenic lines were established and examined. Both genes showed similar patterns of expression in amphidial (head) neurons, which relate to sensation and signal transduction. Further study by heterologous genetic complementation in a daf-2-deficient strain of C. elegans (CB1370) showed partial rescue of function by Hc-daf-2. Taken together, these findings provide a first insight into the roles of Hc-daf-2/. Hc-DAF-2 in the biology and development of H. contortus, particularly in the transition to parasitism. © 2014 Australian Society for Parasitology Inc.
Quantifying the sources of variation in eosinophilia among Scottish blackface lambs with mixed, predominantly Teladorsagia circumcincta nematode infection
- Jenvey, Caitlin, Almasi, Fazel, Halliwell, Emma, Piedrafita, David, Preston, Sarah
- Authors: Jenvey, Caitlin , Almasi, Fazel , Halliwell, Emma , Piedrafita, David , Preston, Sarah
- Date: 2021
- Type: Text , Journal article
- Relation: Veterinary Parasitology Vol. 300, no. (2021), p.
- Full Text:
- Reviewed:
- Description: Eosinophils play a key role in defence against gastrointestinal nematodes. There is considerable variation among animals in the intensity of eosinophilia following nematode infection. However, the statistical distribution of eosinophils among animals has still to be determined. A better description of the variation among animals could provide biological insight and determine the most appropriate way to analyse the effect of eosinophils. We estimated blood eosinophil numbers in a flock of Scottish Blackface sheep that were naturally exposed to mixed, predominantly Teladorsagia circumcincta infection. Three of the four eosinophil counts were better described by a gamma distribution than by a lognormal distribution. The scale and shape parameters of the gamma distribution varied over time. Eosinophil counts differed among animals kept on separate fields before weaning and between singletons and twins but were not significantly different between years and genders. Eosinophil counts also differed among offspring from different sires and dams. The parameters of the gamma distribution were used to enable a power analysis. Large numbers of animals were required to reliably detect even large differences between two groups. These results indicate that methods appropriate for gamma distributions, such as generalized linear mixed models, will provide more reliable inferences than traditional methods of analysis and experimental design. © 2021 The Author(s). **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “David Piedrafita and Sarah Preston” is provided in this record**
- Authors: Jenvey, Caitlin , Almasi, Fazel , Halliwell, Emma , Piedrafita, David , Preston, Sarah
- Date: 2021
- Type: Text , Journal article
- Relation: Veterinary Parasitology Vol. 300, no. (2021), p.
- Full Text:
- Reviewed:
- Description: Eosinophils play a key role in defence against gastrointestinal nematodes. There is considerable variation among animals in the intensity of eosinophilia following nematode infection. However, the statistical distribution of eosinophils among animals has still to be determined. A better description of the variation among animals could provide biological insight and determine the most appropriate way to analyse the effect of eosinophils. We estimated blood eosinophil numbers in a flock of Scottish Blackface sheep that were naturally exposed to mixed, predominantly Teladorsagia circumcincta infection. Three of the four eosinophil counts were better described by a gamma distribution than by a lognormal distribution. The scale and shape parameters of the gamma distribution varied over time. Eosinophil counts differed among animals kept on separate fields before weaning and between singletons and twins but were not significantly different between years and genders. Eosinophil counts also differed among offspring from different sires and dams. The parameters of the gamma distribution were used to enable a power analysis. Large numbers of animals were required to reliably detect even large differences between two groups. These results indicate that methods appropriate for gamma distributions, such as generalized linear mixed models, will provide more reliable inferences than traditional methods of analysis and experimental design. © 2021 The Author(s). **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “David Piedrafita and Sarah Preston” is provided in this record**
Increased susceptibility to Haemonchus contortus infection by interleukin-5 modulation of eosinophil responses in sheep
- Hernández, Julia, Meeusen, Els, Rodríguez, Francisco, Piedrafita, David, González, Jorge
- Authors: Hernández, Julia , Meeusen, Els , Rodríguez, Francisco , Piedrafita, David , González, Jorge
- Date: 2020
- Type: Text , Journal article
- Relation: Parasite Immunology Vol. 42, no. 1 (2020), p.
- Full Text:
- Reviewed:
- Description: Eosinophils are prominent effector cells in immune responses against gastrointestinal nematode infections in ruminants, but their in vivo role has been hard to establish in large animals. Interleukin-5 is a key cytokine in the induction and stimulation of anti-parasitic eosinophil responses. This study attempted to modulate the eosinophil response in sheep through vaccination with recombinant interleukin-5 (rIL-5) and determine the effect on subsequent Haemonchus contortus infection. Nematode-resistant Canaria Hair Breed (CHB) sheep vaccinated with rIL-5 in Quil-A adjuvant, had lower blood eosinophil counts and higher mean worm burdens than control sheep vaccinated with Quil-A adjuvant alone. In addition, adult worms in IL-5-vaccinated sheep were significantly longer with higher eggs in utero in female worms, supporting an active role of eosinophils against adult parasites in CHB sheep. These results confirm that eosinophils can play a direct role in effective control of H contortus infection in sheep and offer a new approach to study immune responses in ruminants. © 2019 John Wiley & Sons Ltd
- Authors: Hernández, Julia , Meeusen, Els , Rodríguez, Francisco , Piedrafita, David , González, Jorge
- Date: 2020
- Type: Text , Journal article
- Relation: Parasite Immunology Vol. 42, no. 1 (2020), p.
- Full Text:
- Reviewed:
- Description: Eosinophils are prominent effector cells in immune responses against gastrointestinal nematode infections in ruminants, but their in vivo role has been hard to establish in large animals. Interleukin-5 is a key cytokine in the induction and stimulation of anti-parasitic eosinophil responses. This study attempted to modulate the eosinophil response in sheep through vaccination with recombinant interleukin-5 (rIL-5) and determine the effect on subsequent Haemonchus contortus infection. Nematode-resistant Canaria Hair Breed (CHB) sheep vaccinated with rIL-5 in Quil-A adjuvant, had lower blood eosinophil counts and higher mean worm burdens than control sheep vaccinated with Quil-A adjuvant alone. In addition, adult worms in IL-5-vaccinated sheep were significantly longer with higher eggs in utero in female worms, supporting an active role of eosinophils against adult parasites in CHB sheep. These results confirm that eosinophils can play a direct role in effective control of H contortus infection in sheep and offer a new approach to study immune responses in ruminants. © 2019 John Wiley & Sons Ltd
Strongyloides genotyping: a review of methods and application in public health and population genetics
- Bradbury, Richard, Pafčo, Barbora, Nosková, Eva, Hasegawa, Hideo
- Authors: Bradbury, Richard , Pafčo, Barbora , Nosková, Eva , Hasegawa, Hideo
- Date: 2021
- Type: Text , Journal article , Review
- Relation: International Journal for Parasitology Vol. 51, no. 13-14 (2021), p. 1153-1166
- Full Text:
- Reviewed:
- Description: Strongyloidiasis represents a major medical and veterinary helminthic disease. Human infection is caused by Strongyloides stercoralis, Strongyloides fuelleborni fuelleborni and Strongyloides fuelleborni kellyi, with S. stercoralis accounting for the majority of cases. Strongyloides f. fuelleborni likely represents a zoonosis acquired from non-human primates (NHPs), while no animal reservoir for S. f. kellyi infection has been found. Whether S. stercoralis represents a zoonosis acquired from dogs and cats remains unanswered. Over the past two decades various tools have been applied to genotype Strongyloides spp. The most commonly sequenced markers have been the hyper-variable regions I and IV of the 18S rRNA gene and selected portions of the cytochrome c oxidase subunit I gene. These markers have been sequenced and compared in Strongyloides from multiple hosts and geographical regions. More recently, a machine learning algorithm multi-locus sequence typing approach has been applied using these markers, while others have applied whole genome sequencing. Genotyping of Strongyloides from dogs, cats, NHPs and humans has identified that S. stercoralis likely originated in dogs and adapted to human hosts. It has also been demonstrated that S. stercoralis is distinct from S. f. fuelleborni and S. f. kellyi. Two distinct genetic clades of S. stercoralis exist, one restricted to dogs and another infecting humans, NHPs, dogs and cats. Genotyping of S. f. fuelleborni has identified two separate clades, one associated with African isolates and another Indochinese peninsular clade. This review summarises the history and development of genotyping tools for Strongyloides spp. It describes the findings of major studies to date in the context of the epidemiology and evolutionary biology of these helminths, with a specific focus on human-infecting species. © 2021 Australian Society for Parasitology
- Authors: Bradbury, Richard , Pafčo, Barbora , Nosková, Eva , Hasegawa, Hideo
- Date: 2021
- Type: Text , Journal article , Review
- Relation: International Journal for Parasitology Vol. 51, no. 13-14 (2021), p. 1153-1166
- Full Text:
- Reviewed:
- Description: Strongyloidiasis represents a major medical and veterinary helminthic disease. Human infection is caused by Strongyloides stercoralis, Strongyloides fuelleborni fuelleborni and Strongyloides fuelleborni kellyi, with S. stercoralis accounting for the majority of cases. Strongyloides f. fuelleborni likely represents a zoonosis acquired from non-human primates (NHPs), while no animal reservoir for S. f. kellyi infection has been found. Whether S. stercoralis represents a zoonosis acquired from dogs and cats remains unanswered. Over the past two decades various tools have been applied to genotype Strongyloides spp. The most commonly sequenced markers have been the hyper-variable regions I and IV of the 18S rRNA gene and selected portions of the cytochrome c oxidase subunit I gene. These markers have been sequenced and compared in Strongyloides from multiple hosts and geographical regions. More recently, a machine learning algorithm multi-locus sequence typing approach has been applied using these markers, while others have applied whole genome sequencing. Genotyping of Strongyloides from dogs, cats, NHPs and humans has identified that S. stercoralis likely originated in dogs and adapted to human hosts. It has also been demonstrated that S. stercoralis is distinct from S. f. fuelleborni and S. f. kellyi. Two distinct genetic clades of S. stercoralis exist, one restricted to dogs and another infecting humans, NHPs, dogs and cats. Genotyping of S. f. fuelleborni has identified two separate clades, one associated with African isolates and another Indochinese peninsular clade. This review summarises the history and development of genotyping tools for Strongyloides spp. It describes the findings of major studies to date in the context of the epidemiology and evolutionary biology of these helminths, with a specific focus on human-infecting species. © 2021 Australian Society for Parasitology
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