Brain-tissue cysts in rats infected with the RH strain of Toxoplasma gondii.
Virulent strains of the coccidian parasite Toxoplasma gondii become attenuated so as to survive and complete their life cycle; however, it is not known whether the attenuation process is attributable to an innate cystogenic capacity of the parasite or to host-induced mechanisms. This report presents direct evidence of RH cystogenesis in non-immunised Fischer rats and subsequent attenuation of RH pathogenicity in non-immunised mice following a single passage through rats. Taken together, these preliminary observations tend to suggest that at least one mechanism of T. gondii involves intermediate host attenuation.
Lecomte
V
V
Départment de Parasitologie-Mycologie Médicale et Moléculaire, CNRS URA 1344, Faculté de Médecine, Université Joseph Fourier, La Tronche, France.
Chumpitazi
B F
BF
Pasquier
B
B
Ambroise-Thomas
P
P
Santoro
F
F
D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis; D001921:Brain / Q000469:parasitology*; D002499:Centrifugation, Density Gradient; D005260:Female; D005455:Fluorescent Antibody Technique; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008297:Male; D051379:Mice; D051381:Rats; D011916:Rats, Inbred F344 / Q000469:parasitology*; D012692:Serial Passage; D014122:Toxoplasma / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000469:parasitology*; D014774:Virulence
D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D007075:Immunoglobulin M