INTRANASAL INOCULATION OF MYCOPLASMA-PULMONIS IN MICE WITH SEVERE COMBINED IMMUNODEFICIENCY (SCID) CAUSES A WASTING DISEASE WITH GRAVE ARTHRITIS

Mycoplasma pulmonis or Myc. pneumoniae were inoculated intranasally to C.B-17 scid/scid mice (severe combined immunodeficient (SCID) mice). Immunocompetent C.B-17 mice were inoculated as controls. During the ob servation period of 5 weeks the mice were killed and necropsied. Mycop lasma pulmonis was recovered from all of the inoculated mice, and diss emination to various tissues increased with time. SCID mice, unlike im munocompetent mice, did not show lung lesions but exhibited severe inf lammatory changes of the joints. Mycoplasma pulmonis, however, was iso lated both from the lungs and the articular lesions. In addition, SCID mice infected for more than 3 weeks suffered from a pronounced loss o f weight and emaciation. In the experiment with Myc. pneumoniae the ag ent could be reisolated, but lesions were not found in any of the infe cted mice. Mycoplasma pulmonis infection in SCID mice may be useful as a model of arthritis in immunodeficient humans.