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09:03
Forward Genetic Approaches in Chlamydia trachomatis
Published on: October 23, 2013
THE PROBABLE NATURE OF THE INFECTIOUS AGENT OF TRACHOMA
L A Julianelle1, R W Harrison, M C Morris
1Oscar Johnson Institute, Washington University School of Medicine, St. Louis.
The Journal of Experimental Medicine
|October 30, 2009
Summary
The infectious agent causing trachoma, a serious eye infection, was found to be difficult to filter and could not be grown in tissue cultures. Accumulated evidence strongly suggests this agent is a virus.
Area of Science:
- Ophthalmology
- Microbiology
- Virology
Background:
- Trachoma is a leading cause of preventable blindness worldwide.
- The exact nature of the infectious agent responsible for trachoma has been a subject of investigation.
Purpose of the Study:
- To characterize the infectious agent of trachoma.
- To determine if the agent could be isolated and cultivated.
- To gather evidence supporting its classification as a virus.
Main Methods:
- Passage of the infectious agent through rabbit testicles and intracerebral inoculation.
- Filtration experiments using various filter types (Seitz, Kramer, Berkefeld, Elford).
- Tissue culture experiments under diverse conditions and inactivation studies.
Main Results:
- The infectious agent could be freed from bacteria via rabbit testicle passage, retaining infectivity.
- Filtration proved difficult, and tissue cultures were unsuccessful in cultivating the agent.
- The agent was inactivated by specific chemicals and heat (45-50°C for 15 minutes), and could not be preserved in glycerine.
Conclusions:
- The infectious agent of trachoma is filterable with difficulty.
- The agent could not be cultivated in vitro using standard tissue culture methods.
- Experimental findings strongly indicate that the infectious agent of trachoma is a virus.
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