Project description:This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/ Teladorsagia circumcincta, the brown stomach worm, is the most important gastro-intestinal parasite of sheep in temperate regions and is present on 100% of sheep farms in the UK. Infection with T. circumcincta causes a spectrum of disease in the host, ranging from weight loss to death, and results in significant production losses. Parasitic disease is currently controlled by treatment with anthelmintics but resistance to these drugs is widespread and threatens the viability of the livestock industry. There are now well-documented cases of UK farms harbouring triple-resistant T. circumcincta, which can no longer be controlled by any of the three major anthelmintic classes, forcing farmers to abandon sheep rearing. High-throughput sequencing of life stages of T. circumcincta will be used for gene finding and transcriptome analysis.
Project description:Gastrointestinal nematode (GIN) is a major economic and health concern is sheep farming. Sheep breeds such as Texel are relatively resistant to GIN than the Suffolk. With the objective to understand the underlying genetic mechanism of resistance and susceptibility at the transcriptomic level, two groups of animal from both the breed were artificially (orally) infected with 30,000 L3 larvae of prominent GIN Teladorsagia circumcincta. Subgroups of animals from each breed were slaughtered on day 0, 3, 7, 14 and 21 of post infection (p.i.). Transcriptomic profiling of abomasal lymph node was performed using RNA-seq. The perturbations in gene expression profiles in both the breeds were evident and Texel showed a more tightly regulated immune response than the Suffolk. The number of differentially expressed (DE) genes between the breeds was highest (437) on un-infected control (day 0) and lowest (173) on day 7 p.i.. Pathway analysis of DE genes identified 3 significant pathways, which involved only more highly expressed genes of Suffolk breed on day 0 and only more highly expressed genes of Texel (with one exception) on day 7 p.i.. The Th1, Th2 and Treg response was evident in response to GIN in Texel and was synchronized, while in Suffolk Th1 response was reduced after infection and pronounced Th2 and Treg was not evident. The study suggests maximum level of transcriptional activity in both breeds on day 7 p.i. and there was a shift of transcriptional activity from Suffolk on day 0 to Texel on day 7 p.i.. Suffolk had a reduced Th1 response with less pronounced Th2 and Treg immune response, while Texel had an active and synchronized Th1/Th2/Treg immune response in response to GIN infection. Abomasal lymph node tissue was taken from control (n=10) and experimentally infected (with T. circumcincta) lambs (n=36) from Texel and Suffolk breed on day 0, 3, 7, 14 and 21 post infection.
Project description:Gastrointestinal nematode (GIN) is a major economic and health concern is sheep farming. Sheep breeds such as Texel are relatively resistant to GIN than the Suffolk. With the objective to understand the underlying genetic mechanism of resistance and susceptibility at the transcriptomic level, two groups of animal from both the breed were artificially (orally) infected with 30,000 L3 larvae of prominent GIN Teladorsagia circumcincta. Subgroups of animals from each breed were slaughtered on day 0, 3, 7, 14 and 21 of post infection (p.i.). Transcriptomic profiling of abomasal lymph node was performed using RNA-seq. The perturbations in gene expression profiles in both the breeds were evident and Texel showed a more tightly regulated immune response than the Suffolk. The number of differentially expressed (DE) genes between the breeds was highest (437) on un-infected control (day 0) and lowest (173) on day 7 p.i.. Pathway analysis of DE genes identified 3 significant pathways, which involved only more highly expressed genes of Suffolk breed on day 0 and only more highly expressed genes of Texel (with one exception) on day 7 p.i.. The Th1, Th2 and Treg response was evident in response to GIN in Texel and was synchronized, while in Suffolk Th1 response was reduced after infection and pronounced Th2 and Treg was not evident. The study suggests maximum level of transcriptional activity in both breeds on day 7 p.i. and there was a shift of transcriptional activity from Suffolk on day 0 to Texel on day 7 p.i.. Suffolk had a reduced Th1 response with less pronounced Th2 and Treg immune response, while Texel had an active and synchronized Th1/Th2/Treg immune response in response to GIN infection.
Project description:Effect of infection with and treatment of sensitive and resistant strains of Teladorsagia circumcincta on the ovine intestinal microbiota
Project description:Background: Gastrointestinal nematodes are a serious cause of morbidity and mortality in grazing ruminants. The major ovine defence mechanism is acquired immunity, which develops over time in response to infection. Nematode resistance varies both within and between breeds and is moderately heritable (h ~ 0.3). A detailed understanding of the genes and mechanisms involved in protective immunity, and the factors that regulate this response, is required to aid future breeding strategies as well as the development of effective and sustainable nematode control methods. The aim of this study was to compare the abomasal lymph node transcriptome of resistant and susceptible lambs in order to determine biological processes differentially expressed between resistant and susceptible lambs. Results: Scottish Blackface lambs, with divergent phenotypes for resistance, were challenged with 30,000 Teladorsagia circumcincta larvae (L3), and abomasal lymph node recovered at 7 and 14 days post-infection (dpi). High-throughput sequencing of abomasal lymph node cDNA was used to quantitatively sample the transcriptome with an average of 32 million reads per sample. A total of 194 and 144 genes were differentially expressed between resistant and susceptible lambs at 7 and 14 dpi respectively. Differentially expressed networks and biological processes were identified using Ingenuity Pathway Analysis. Resistant animals appear to generate a more rapid immune response as at 7 dpi processes relating to homing of lymphocytes, leukocyte migration and migration of antigen presenting cells were up-regulated. In susceptible animals this response appears to be delayed until approximately 14 dpi. Twenty-four Single Nucleotide Polymorphims (SNP), within 11 differentially expressed genes were tested for association with gastrointestinal nematode resistance in the Scottish Blackface lambs. Four SNPs in two genes (SLC30A2, and ALB) were suggestively associated with faecal egg count. Conclusions: A large number of genes were differentially expressed in the abomasal lymph node of resistant and susceptible lambs responding to gastrointestinal nematode challenge. Resistant Scottish Blackface lambs appear to generate a more rapid immune response to T. circumcincta. In susceptible lambs this response appears to be delayed until approximately 14 days post infection. SNP in two differentially expressed genes were suggestively associated with faecal egg count indicating that differentially expressed genes can be considered as candidate loci for mediating nematode resistance.