[Plaque assay for Chlamydia psittaci in tissue samples (author's transl)].

Direct isolation of Chlamydia psittaci (var, ovis) from mouse spleen was performed in parallel by plaque assay on McCoy cells and by staining of cytoplasmic inclusions in HeLa 229 cells. There was a significant difference between the frequency of isolation: the plaque technique was highly sensitive and reproducible; it offers a potential tool for investigations requiring the accurate quantitation of Chlamydiae in tissue sample.