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A PYOGENIC FILTERABLE AGENT IN THE ALBINO RAT
1Institute of Cancer Research and the Department of Bacteriology, College of Physicians and Surgeons, Columbia University, New York.
Abstract:
A filterable agent resembling the viruses is described. It was encountered in sarcoma 39, a propagable neoplasm of the white rat, and has now been maintained in this species for 28 passages over a period of some 7 months without appreciable loss in virulence. Its chief effect is the production of large abscesses in an animal species comparatively resistant both to viral diseases and suppuration. The white mouse is more susceptible than the white rat, the rabbit less so, and the guinea pig highly resistant. The agent has been repeatedly recovered from sarcoma 39 treated in special ways, but under the ordinary circumstances of routine transplantation it does not manifest itself. As yet there is no certainty on where it came from or how it maintains itself under natural conditions.
Insights
A novel filterable agent, similar to viruses, was discovered in rat sarcoma 39. This agent causes significant abscess formation in rats and mice, with varying susceptibility across different animal models.
Area of Science:
- * Oncology
- * Virology
- * Pathology
Background:
- * A propagable neoplasm, sarcoma 39, was identified in white rats.
- * This tumor served as the source for isolating a novel agent.
Purpose of the Study:
- * To describe a newly discovered filterable agent resembling viruses.
- * To investigate the agent's effects and pathogenicity in various animal models.
- * To determine the conditions under which the agent can be recovered.
Main Methods:
- * Isolation and serial passage of the agent in white rats (28 passages over 7 months).
- * Inoculation of the agent into different animal species (white rat, mouse, rabbit, guinea pig) to assess susceptibility.
- * Attempts to recover the agent from transplanted sarcoma 39 under varied conditions.
Main Results:
- * The agent was maintained in rats for 7 months without loss of virulence.
- * It induced large abscesses in white rats and mice, with differential susceptibility observed.
- * The agent was recoverable from specially treated sarcoma 39 but not under routine transplantation.
Conclusions:
- * A virus-like filterable agent associated with rat sarcoma 39 has been identified.
- * The agent exhibits significant abscess-forming potential in susceptible species.
- * Its origin and natural maintenance mechanisms remain undetermined.
