title: Mycobacterium marinum causes both long-term subclinical infection and acute disease in the leopard frog (Rana pipiens).
abstract: Mycobacterium marinum grows at an optimal temperature of 33 degrees C, far lower than that for M. tuberculosis. Consequently, M. marinum infection of mammals is restricted largely to the cooler surfaces of the body, such as the extremities, but it causes a systemic infection in a large number of poikilothermic animals. Here, we describe a laboratory animal model for M. marinum disease in the leopard frog (Rana pipiens), a natural host species. M. marinum causes a chronic granulomatous, nonlethal disease in immunocompetent frogs. Immunosuppression of the frogs with hydrocortisone results in an acute, fulminant, lethal disease. This animal model, in which a spectrum of tuberculosis-like disease can be produced, will be useful for the dissection of the genetic basis of mycobacterial pathogenesis.
authors.affiliation: Department of Microbiology and Immunology, Stanford University School of Medicine, California 94305-5402, USA. lalitar@cmgm.stanford.edu
authors.forename: L
authors.initials: L
authors.lastname: Ramakrishnan
authors.forename: R H
authors.initials: RH
authors.lastname: Valdivia
authors.forename: J H
authors.initials: JH
authors.lastname: McKerrow
authors.forename: S
authors.initials: S
authors.lastname: Falkow
mesh_terms: D000208:Acute Disease; D000818:Animals; D002908:Chronic Disease; D004195:Disease Models, Animal; D006099:Granuloma / Q000209:etiology / Q000382:microbiology* / Q000401:mortality; D006854:Hydrocortisone / Q000008:administration & dosage; D007274:Injections, Intraperitoneal; D008297:Male; D009154:Mutation; D009165:Mycobacterium Infections, Nontuberculous / Q000209:etiology* / Q000382:microbiology* / Q000401:mortality; D009170:Nontuberculous Mycobacteria / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D011894:Rana pipiens; D014498:Uracil / Q000378:metabolism
chemical_list: D014498:Uracil; D006854:Hydrocortisone