title: Host cells of Toxoplasma gondii encystation in infected primary culture from mouse brain.
abstract: In order to identify brain cell types that serve as host cells of Toxoplasma gondii encystation primary cultures from murine brain were infected and stained for neural and parasite stage-specific markers. In mixed culture inoculated with T. gondii tachyzoites, MAP2+ neurons, GFAP+ astrocytes, F4/80+ microglia, and O1+ oligodendrocytes proved to be infected as detected by parallel labeling of SAG1. At 4 days following infection with bradyzoites, cysts developed in neuronal, astroglial, and microglial host cells as clarified using bradyzoite-specific antibody 4F8. Additional staining of SAG1 revealed that astrocytes in bradyzoite-infected brain cell culture can also harbor tachyzoite-containing vacuoles. Stage conversion was observed shortly after inoculation and was accompanied by an increase in] parasite proliferation. However, tachyzoites became rare in prolonged culture. By contrast, the numbers of cysts and of the bradyzoites isolated multiplied during long-term culture. These findings demonstrate that both glial and neuronal host cells allow T. gondii encystation in the absence of T cell-derived cytokines and imply that a brain-internal spreading of bradyzoites may sustain chronic infection.
authors.affiliation: Institute for Medical Microbiology and Virology, Düesseldorf, Germany. hans-georg.fischer@uni-duesseldorf.de
authors.forename: H G
authors.initials: HG
authors.lastname: Fischer
authors.forename: B
authors.initials: B
authors.lastname: Nitzgen
authors.forename: G
authors.initials: G
authors.lastname: Reichmann
authors.forename: U
authors.initials: U
authors.lastname: Gross
authors.forename: U
authors.initials: U
authors.lastname: Hadding
mesh_terms: D000818:Animals; D001921:Brain / Q000469:parasitology*; D002478:Cells, Cultured; D003560:Cysts / Q000469:parasitology; D019084:Fluorescent Antibody Technique, Indirect; D051379:Mice; D008807:Mice, Inbred BALB C; D009457:Neuroglia / Q000469:parasitology; D009474:Neurons / Q000469:parasitology; D013997:Time Factors; D014122:Toxoplasma / Q000254:growth & development*