title: Cytological changes related to Brucella canis variants uptake in vitro.
abstract: In this study, evidence for in vitro uptake, invasion, and cytopathogonomic effects of normal and variant strains of B. canis on tissue culture, is presented. B. canis L-phase were penicillin-induced and these microorganisms produced revertants on penicillin-free media. Tissue culture (LLC-MK2) cells were divided into different normal and variant-infected groups (I-IV), including controls. Bright-field and electron microscopic observations indicated uptake of all the strains and recognizable host cell damage (CPE) to varying degrees. At 72 h after infection, the extent of damage by L-phase was the least (55.5% CPE). The L-phase-derived revertants resulted in 80% damage; this approximates the adverse effect of normal B. canis (85%). In addition to these gross changes, various structural abnormalities, including pyknosis, nuclear disorganization, vacuolation, and karyorrhexis, were apparent. The implications of these findings and the indirect role of the L-phase in brucellosis due to B. canis are discussed.
mesh_terms: D000818:Animals; D002002:Brucella / Q000254:growth & development*; D002460:Cell Line; D000882:Haplorhini; D007668:Kidney; D007740:L Forms / Q000254:growth & development*