This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': 'Chlamydia are isolated by : \nSelect and explain. \nA. Enzyme immune assay, B. Yolk sac inoculation, C. Direct immunofluorescence, D. Micro immunofluorescence', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Isolation of chlamydiae can done by :\nInoculationinto yolk sac/embryonated eggs of 6-8 day old chick embryo which may be pretreated by streptomycin or polymyxin\nInculation into experimental animals (mice)\nTissue/cell culture :\nPreferred mode\nCommonly used cell lines are McCoy and HeLa cells.\nCell cultures are pretreated by irradiation or chemicals such as 5-iodo – 2 deoxyuridic or cycloheximide to enhance replication and detection of inclusion bodies.\nPretreatment with DEAE dextrax or centrifugation after inoculation, promotes contact between chlamydiae particles and cell monolayer.', 'role': 'assistant'}]