title: The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs.
abstract: Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.
authors: 1  Center for Microbial Genetics and Genomics, Northern Arizona University, PO Box 4073, Flagstaff, Arizona 86011, USA.
authors: Joseph D
authors: JD
authors: Busch
authors: Roger
authors: R
authors: Van Andel
authors: Nathan E
authors: NE
authors: Stone
authors: Kacy R
authors: KR
authors: Cobble
authors: Roxanne
authors: R
authors: Nottingham
authors: Judy
authors: J
authors: Lee
authors: Michael
authors: M
authors: VerSteeg
authors: Jeff
authors: J
authors: Corcoran
authors: Jennifer
authors: J
authors: Cordova
authors: William
authors: W
authors: Van Pelt
authors: Megan M
authors: MM
authors: Shuey
authors: Jeffrey T
authors: JT
authors: Foster
authors: James M
authors: JM
authors: Schupp
authors: Stephen
authors: S
authors: Beckstrom-Sternberg
authors: James
authors: J
authors: Beckstrom-Sternberg
authors: Paul
authors: P
authors: Keim
authors: Susan
authors: S
authors: Smith
authors: Julia
authors: J
authors: Rodriguez-Ramos
authors: Judy L
authors: JL
authors: Williamson
authors: Tonie E
authors: TE
authors: Rocke
authors: David M
authors: DM
authors: Wagner
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D005260:Female; D007113:Immunity, Innate; D008297:Male; D010930:Plague / Q000097:blood / Q000276:immunology / Q000401:mortality / Q000662:veterinary*; D012589:Sciuridae / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial