Now showing 1 - 5 of 5
  • Publication
    The immunoregulatory effects of co-infection with Fasciola hepatica: From bovine tuberculosis to Johne's disease
    Fasciola hepatica (liver fluke) is a parasite prevalent in much of the world that causes the economically-important disease of fasciolosis in livestock. The threat that this disease poses extends beyond its direct effects due to the parasite's immunomodulatory effects. Research at this laboratory is focusing on whether this immunoregulation can, in animals infected with liver fluke, exert a bystander effect on concurrent infections in the host. It has already been established that F. hepatica infection reduces cell mediated immune responses to Mycobacterium bovis in cattle, and that the interaction between the two pathogens can be detected on an epidemiological scale. This review explores the immunological consequences of co-infection between F. hepatica and other bacterial infections. Arguments are presented suggesting that immunity of cattle to Mycobacterium avium subsp. paratuberculosis is also likely to be affected.
      463Scopus© Citations 13
  • Publication
    UCD Access Symposium Proceedings 2017
    (UCD Access and Lifelong Learning, 2017-11) ;
    The UCD Access Symposium was held in University College Dublin on June 9th 2017. These Symposium Proceedings are part of a series chronicling UCD's journey to becoming a diverse and inclusive scholarly community. The aim of this publication is to contribute to the scholarship and practice of inclusion, and help advance the integration of access and widening participation into everyday life in higher education. This Symposium Proceedings is laid out in 6 sections. The keynote address by Professor, Diane Reay, University of Cambridge, focuses on efforts to widening access and participation in the UK and explored why it has not resulted in a more socially just HE system. Inclusive Practice in UCD features the book review by Professor Lizbeth Goodman, UCD. UCD Community Outreach showcases three examples of outreach and engagement practice, while Mainstream Academic Support describes four creative examples of mainstream academic support.
  • Publication
    Comparison of diagnostic techniques for the detection of Cryptosporidium oocysts in animal samples
    While a large number of laboratory methods for the detection of Cryptosporidium oocysts in faecal samples are now available, their efficacy for identifying asymptomatic cases of cryptosporidiosis is poorly understood. This study was carried out to determine a reliable screening test for epidemiological studies in livestock. In addition, three molecular tests were compared to identify Cryptosporidium species responsible for the infection in cattle, sheep and horses. A variety of diagnostic tests including microscopic (Kinyoun's staining), immunological (Direct Fluorescence Antibody tests or DFAT), enzyme-linked immunosorbent assay (ELISA), and molecular methods (nested PCR) were compared to assess their ability to detect Cryptosporidium in cattle, horse and sheep faecal samples. The results indicate that the sensitivity and specificity of each test is highly dependent on the input samples; while Kinyoun's and DFAT proved to be reliable screening tools for cattle samples, DFAT and PCR analysis (targeted at the 18S rRNA gene fragment) were more sensitive for screening sheep and horse samples. Finally different PCR primer sets targetedat the same region resulted in the preferential amplification of certain Cryptosporidium species when multiple species were present in the sample. Therefore, for identification of Cryptosporidium spp. in the event of asymptomatic cryptosporidiosis, the combination of different 18S rRNA nested PCR primer sets is recommended for further epidemiological applications and also tracking the sources of infection.
      397Scopus© Citations 24
  • Publication
    Migration of Fasciola hepatica newly excysted juveniles is inhibited by high-mannose and oligomannose-Type N-glycan-binding lectins
    (Cambridge University Press, 2017-11-01) ; ;
    Fasciola hepatica has both zoonotic importance and high economic impact in livestock worldwide. After ingestion by the definitive host, the Newly Excysted Juveniles (NEJ) penetrate the intestine before reaching the peritoneal cavity. The role of some NEJ-derived proteins in invasion has been documented, but the role of NEJ glycans or lectin-binding receptors during initial infection in the gut is still unknown. To address these questions, the migration of NEJ through rat intestine was recorded at 30 min intervals up to 150 min by two ex vivo methods. Firstly, jejunal sheets were challenged with NEJ incubated with biotinylated lectins. Secondly, untreated NEJ were incubated with distal jejunum pre-Treated with lectins. Both Concanavalin A (ConA) and Galanthus nivalis (GNL), which recognize mannose-Type N-glycans, significantly inhibited NEJ migration across the jejunum. Most of the lectins bound to the tegument and oral sucker of the NEJ, but only ConA and GNL maintained this interaction over 150 min. None of the lectins examined significantly reduced NEJ migration when pre-incubated with jejunal sheets, suggesting that host glycans might not be essential for initial binding/recognition of the gut by NEJ. Agents capable of blocking mannose-Type N-glycans on the NEJ tegument may have potential for disrupting infection.
      283Scopus© Citations 9
  • Publication
    Antibody recognition of cathepsin L1-derived peptides in Fasciola hepatica-infected and/or vaccinated cattle and identification of protective linear B-cell epitopes
    Fasciola hepatica infection causes important economic losses in livestock and food industries around the world. In the Republic of Ireland F. hepatica infection has an 76% prevalence in cattle. Due to the increase of anti-helminthic resistance, a vaccine-based approach to control of Fasciolosis is urgently needed. A recombinant version of the cysteine protease cathepsin L1 (rmFhCL1) from F. hepatica has been a vaccine candidate for many years. We have found that vaccination of cattle with this immunodominant antigen has provided protection against infection in some experimental trials, but not in others. Differential epitope recognition between animals could be a source of variable levels of vaccine protection. Therefore, we have characterised for first time linear B-cell epitopes recognised within the FhCL1 protein using sera from F. hepatica-infected and/or vaccinated cattle from two independent trials. Results showed that all F. hepatica infected animals recognised the region 19–31 of FhCL1, which is situated in the N-terminal part of the pro-peptide. Vaccinated animals that showed fluke burden reduction elicited antibodies that bound to the regions 120–137, 145–155, 161–171 of FhCL1, which were not recognised by non-protected animals. This data, together with the high production of specific IgG2 in animals showing vaccine efficacy, suggest important targets for vaccine development.
      451Scopus© Citations 23