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Attenuated Creutzfeldt-Jakob Disease agents can hide more virulent infections

L Manuelidis1, Z Yun Lu

  • 1Section of Neuropathology, Yale Medical School 310 Cedar Street, New Haen, CT 06510, New Haven, USA. laura.manuelidis@yale.edu

Neuroscience Letters
|October 19, 2000
PubMed

Insights

A slow strain of Creutzfeldt-Jakob Disease (CJD) can suppress a faster, virulent agent. In some cases, the faster agent reappeared, suggesting CJD can conceal other prion diseases.

Area of Science:

  • Neuroscience
  • Infectious Diseases
  • Prion Biology

Background:

  • Previous research demonstrated that a slow infectious strain of Creutzfeldt-Jakob Disease (CJD) could suppress a fast, virulent agent.
  • This suppression was observed when the fast agent was injected intracerebrally 80 days after the slow agent.

Purpose of the Study:

  • To investigate the extent of suppression of the fast FU agent by the slow SY agent.
  • To determine if a 'chimera' with intermediate incubation properties formed, as predicted by prion theory.
  • To explore the implications for understanding CJD and related prion diseases, such as variant CJD.

Main Methods:

  • Intracerebral injection of slow SY and fast FU agents into mice.
  • Passaging of representative brains from infected mice to analyze agent presence and characteristics.
  • Pathological examination of brain tissue to assess disease progression and agent interaction.

Main Results:

  • Typical suppressed mice showed complete obliteration of the fast FU agent.
  • Two aberrant mice exhibited mixed SY and FU infections, with FU reappearing late in the SY disease course.
  • These findings suggest that less virulent CJD strains can mask more virulent agents.

Conclusions:

  • The study provides a model for agent-induced repression, indicating that less virulent CJD strains can conceal other agents like variant CJD.
  • The results suggest potential targets beyond prion protein (PrP) are involved in infection elimination.
  • This has significant implications for diagnosing and managing prion diseases, particularly in older individuals or those with less typical presentations.

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