TitleDetection of bacterial-reactive natural IgM antibodies in desert bighorn sheep populations.
Publication TypeJournal Article
Year of Publication2017
AuthorsDugovich, BS, Peel, MJ, Palmer, AL, Zielke, RA, Sikora, AE, Beechler, B, Jolles, AE, Epps, CW, Dolan, BP
JournalPLoS One
Volume12
Issue6
Paginatione0180415
Date Published2017
ISSN1932-6203
KeywordsAnimals, Desert Climate, Enzyme-Linked Immunosorbent Assay, Immunoglobulin M, Sheep, Sheep Diseases
Abstract

Ecoimmunology is a burgeoning field of ecology which studies immune responses in wildlife by utilizing general immune assays such as the detection of natural antibody. Unlike adaptive antibodies, natural antibodies are important in innate immune responses and often recognized conserved epitopes present in pathogens. Here, we describe a procedure for measuring natural antibodies reactive to bacterial antigens that may be applicable to a variety of organisms. IgM from desert bighorn sheep plasma samples was tested for reactivity to outer membrane proteins from Vibrio coralliilyticus, a marine bacterium to which sheep would have not been exposed. Immunoblotting demonstrated bighorn sheep IgM could bind to a variety of bacterial cell envelope proteins while ELISA analysis allowed for rapid determination of natural antibody levels in hundreds of individual animals. Natural antibody levels were correlated with the ability of plasma to kill laboratory strains of E. coli bacteria. Finally, we demonstrate that natural antibody levels varied in two distinct populations of desert bighorn sheep. These data demonstrate a novel and specific measure of natural antibody function and show that this varies in ecologically relevant ways.

DOI10.1371/journal.pone.0180415
Alternate JournalPLoS One
PubMed ID28662203
PubMed Central IDPMC5491220