title: Serum antibody responses in pigs trickle-infected with Ascaris and Trichuris: Heritabilities and associations with parasitological findings.
abstract: A humoral immune response following helminth infection in pigs is well documented. However, it has been difficult to confirm the existence of antibody mediated resistance against the large roundworm, Ascaris suum, and whipworm, Trichuris suis, in experimental settings by correlating worm burdens or egg excretion with specific antibody levels. We set out to investigate the association between worm load and T. suis and A. suum specific serum antibody levels (IgG1, IgG2 and IgA) against excretory-secretory products of adults and third stage larvae, respectively, measured at 0, 7 and 14 weeks p.i. in a trickle-infected F1-resource-population of crossbred pigs (n=195). Furthermore, we wanted to determine the heritability of these antibody isotypes during the course of infection. Most pigs remained infected with A. suum throughout the experiment while they expelled T. suis between 7 and 14 weeks post infection (p.i.). Parasite specific IgG1 and IgA were significantly (P<0.001) elevated after 7 and 14 weeks of infection, whereas parasite specific IgG2 levels only changed slightly at 14 weeks p.i.. However, the observed association between specific antibody isotype levels and faecal egg counts and macroscopic worm load was weak. The relative heritabilities of the different parasite specific isotypes were assessed and resulted in significant heritability estimates for parasite specific IgG1 and IgA. The highest heritabilities were found for A. suum specific IgG1 (h(2)=0.41 and 0.46 at 7 and 14 weeks p.i., respectively). Thus, the present study demonstrates that host genetic factors influence the IgG1 and IgA antibody isotype responses specific to two of the most common gastrointestinal nematodes of swine whereas specific antibody levels were poorly associated with egg excretion and the presence of macroscopic worms.
authors.affiliation: Parasitology and Fish Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1871 Frederiksberg, Denmark.
authors.forename: Helene
authors.initials: H
authors.lastname: Kringel
authors.affiliation: Parasitology and Fish Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1871 Frederiksberg, Denmark.
authors.forename: Stig Milan
authors.initials: SM
authors.lastname: Thamsborg
authors.affiliation: Parasitology and Fish Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1871 Frederiksberg, Denmark.
authors.forename: Heidi Huus
authors.initials: HH
authors.lastname: Petersen
authors.affiliation: Texas Biomedical Research Institute, 7620N. W. Loop 410, San Antonio, TX, USA; South Texas Diabetes and Obesity Institute, University of Texas Health Science Center, San Antonio, TX, USA.
authors.forename: Harald Heinz Herbert
authors.initials: HH
authors.lastname: Göring
authors.affiliation: Animal Genetics, Bioinformatics and Breeding, Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Grønnegårdsvej 3, DK-1870 Frederiksberg, Denmark.
authors.forename: Per
authors.initials: P
authors.lastname: Skallerup
authors.affiliation: Parasitology and Fish Diseases, Department of Veterinary Disease Biology, University of Copenhagen, Dyrlægevej 100, DK-1871 Frederiksberg, Denmark; Animal Genetics, Bioinformatics and Breeding, Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Grønnegårdsvej 3, DK-1870 Frederiksberg, Denmark. Electronic address: pn@sund.ku.dk.
authors.forename: Peter
authors.initials: P
authors.lastname: Nejsum
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000918:Antibody Specificity / Q000235:genetics; D001196:Ascariasis / Q000097:blood / Q000276:immunology / Q000662:veterinary*; D001200:Ascaris; D005243:Feces / Q000469:parasitology; D020022:Genetic Predisposition to Disease; D007070:Immunoglobulin A / Q000097:blood / Q000235:genetics; D007074:Immunoglobulin G / Q000097:blood / Q000235:genetics; D010270:Parasite Egg Count; D059208:Parasite Load; D013045:Species Specificity; D013552:Swine; D013553:Swine Diseases / Q000235:genetics / Q000469:parasitology*; D014257:Trichuriasis / Q000097:blood / Q000276:immunology / Q000662:veterinary*; D014258:Trichuris
chemical_list: D000909:Antibodies, Helminth; D007070:Immunoglobulin A; D007074:Immunoglobulin G
keywords: Heritability; Immunoglobulins; Pig; Worm load