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Hypothesis on the molecular basis of nononcogenic retroviral diseases

J E Clements

    Reviews of Infectious Diseases
    |January 1, 1985
    PubMed

    Insights

    Nononcogenic retroviruses cause chronic diseases like visna-maedi by infecting specific cells and persisting lifelong. Viral spread occurs despite host immunity through antigenic drift or immune modulation.

    Area of Science:

    • Virology
    • Immunology
    • Pathology

    Background:

    • Retroviruses, both oncogenic and nononcogenic, share similar structures and replicate via reverse transcription.
    • Nononcogenic retroviruses are characterized by the chronic inflammatory or degenerative diseases they induce.
    • Examples of diseases caused by nononcogenic retroviruses include visna-maedi in sheep, caprine arthritis and encephalitis, equine infectious anemia, and chronic spongiform polioencephalomyelopathy in mice.

    Purpose of the Study:

    • To differentiate nononcogenic retroviruses from oncogenic ones based on disease outcomes.
    • To explore the mechanisms underlying chronic disease development caused by nononcogenic retroviruses.
    • To discuss the molecular basis and biological significance of antigenic drift in visna virus.

    Main Methods:

    • Comparative analysis of retroviral structures and replication.
    • Identification of specific end-stage cells targeted by nononcogenic retroviruses.
    • Investigation of viral persistence and spread mechanisms in the face of host immunity.
    • Molecular analysis of antigenic drift in visna virus.

    Main Results:

    • Nononcogenic retroviruses selectively infect specific end-stage cells, leading to chronic diseases.
    • Lifelong viral persistence is a common feature, with viral spread occurring despite host immunity.
    • Mechanisms of viral spread include antigenic drift and modulation of the host immune response.
    • The molecular basis and biological significance of antigenic drift in visna virus were examined.

    Conclusions:

    • Nononcogenic retroviruses cause specific chronic inflammatory or degenerative diseases through selective cell tropism.
    • Viral persistence and evasion of host immunity, via antigenic drift or immune modulation, are key to disease progression.
    • Understanding these mechanisms is crucial for managing retroviral infections and associated diseases.

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