title: Mountain Yellow-legged Frogs (Rana muscosa) did not Produce Detectable Antibodies in Immunization Experiments with Batrachochytrium dendrobatidis.
abstract: Chytridiomycosis is a devastating infectious disease of amphibians caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). A growing number of studies have examined the role of amphibian adaptive immunity in response to this pathogen, with varying degrees of immune activation reported. Here we present immunologic data for the mountain yellow-legged frog, Rana muscosa, and the Sierra Nevada yellow-legged frog, Rana sierrae, which are two endangered and ecologically important species experiencing Bd-inflicted declines. Previous studies on these species that examined transcriptional response during Bd infection, and the effective of immunization, provided little evidence of immune activation to Bd. However, the studies did not directly assay immune effectors in the frog hosts. We performed experiments to examine antibody production, which is a hallmark of systemic adaptive immune activation. We used controlled laboratory experiments and enzyme-linked immunosorbent assays to examine the antibody response to Bd immunization and live Bd exposure. Rana muscosa and R. sierrae individuals did not produce detectable antibodies with the capacity to bind to denatured Bd antigens under our experimental conditions. While we cannot rule out antibody response to Bd in these species, our results suggest weak, poor, or inefficient production of antibodies to denatured Bd antigens. Our findings are consistent with susceptibility to chytridiomycosis in these species and suggest additional work is needed to characterize the potential for adaptive immunity.
authors.affiliation: 1 Department of Environmental Science, Policy, and Management, University of California, Berkeley, 130 Mulford Hall #3114, Berkeley, California 94720-3114, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Poorten
authors.affiliation: 2 Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, 4314 Life Sciences Building, Santa Barbara, California 93106-9610, USA.
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Stice-Kishiyama
authors.affiliation: 2 Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, 4314 Life Sciences Building, Santa Barbara, California 93106-9610, USA.
authors.forename: Cheryl J
authors.initials: CJ
authors.lastname: Briggs
authors.affiliation: 1 Department of Environmental Science, Policy, and Management, University of California, Berkeley, 130 Mulford Hall #3114, Berkeley, California 94720-3114, USA.
authors.forename: Erica Bree
authors.initials: EB
authors.lastname: Rosenblum
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D000908:Antibodies, Fungal / Q000096:biosynthesis*; D008411:Chytridiomycota / Q000276:immunology*; D007114:Immunization / Q000662:veterinary; D009181:Mycoses / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D011898:Ranidae
chemical_list: D000908:Antibodies, Fungal
keywords: Antibodies; Batrachochytrium dendrobatidis; ELISA; Rana muscosa; Rana sierra; chytridiomycosis