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Journal of virology1989; 63(6); 2492-2496; doi: 10.1128/JVI.63.6.2492-2496.1989

Change in host cell tropism associated with in vitro replication of equine infectious anemia virus.

Abstract: Similar to other human and animal lentiviruses, equine infectious anemia virus (EIAV) is detectable in vivo in cells of the monocyte-macrophage lineage. Owing to their short-lived nature, horse peripheral blood macrophage cultures (HMC) are rarely used for in vitro propagation of EIAV, and equine dermal (ED) or kidney cell cultures, which can be repeatedly passed in vitro, are used in most studies. However, wild-type isolates of EIAV will not grow in these cell types without extensive adaptation, a process which may attenuate viral virulence. To better define the effect of host cell tropism on the virulence and pathogenesis of EIAV, we studied a field isolate of EIAV during in vitro adaptation to growth in an ED cell line. Interestingly, as the virus adapted to growth in ED cells, there was a corresponding decrease in infectivity for HMC, and the final ED-adapted isolate was more than 100-fold more infectious for ED cells than for HMC. In vivo studies indicated that the ED-adapted isolate was able to replicate in experimentally infected horses, although no clinical signs of EIA were observed. Thus, selection for in vitro replication on ED cells correlated with a loss of EIAV tropism for HMC in vitro and was associated with avirulence in vivo.
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Publication Date: 1989-06-01 PubMed ID: 2470916PubMed Central: PMC250709DOI: 10.1128/JVI.63.6.2492-2496.1989Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research focuses on how equine infectious ania virus (EIAV) adapts to growth inside equine dermal cells in culture, and how this adaptation affects its virulence and infectivity in both host cells and live horses.

Overview of Equine Infectious Anemia Virus (EIAV)

  • EIAV is a lentivirus similar to those found in humans and other animals, mainly affecting cells from the monocyte-macrophage lineage.
  • Due to the short-lived nature of horse peripheral blood macrophage cultures (HMC), equine dermal (ED) or kidney cell cultures are usually used in studies for EIAV.
  • It’s crucial to note that wild-type instances of EIAV don’t grow in these cell types without undergoing significant adaptation, which may reduce the virus’s virulence.

Study of EIAV Adaptation in ED Cells

  • The study focused on a field isolate of EIAV and examined its adaptation in vitro to grow in an ED cell line.
  • As the virus adapted to the ED cells, there was a corresponding decrease in infectivity for HMC.
  • Once the virus completed its adaptation to the ED cells, it was over 100 times more infectious for the ED cells than the HMC.

In Vivo Impact of the ED-Adapted Virus

  • When the fully ED-adapted EIAV was introduced into horses in a controlled experiment, it was able to replicate but did not cause any noticeable clinical signs of EIA to appear in the horses.
  • This suggests that the adaptation for growing in ED cells, which correlates with a loss of tropism for HMC in vitro, may also be associated with avirulence (non-disease causing) in vivo.

Implications of the Findings

  • These results could be an important insight into how viruses adapt to various hosts, and how such adaptation influences the virulence of the virus.
  • This could lead to new understandings or approaches for disease prevention and control in horses and potentially other animals affected by similar lentiviruses.

Cite This Article

APA
Carpenter S, Chesebro B. (1989). Change in host cell tropism associated with in vitro replication of equine infectious anemia virus. J Virol, 63(6), 2492-2496. https://doi.org/10.1128/JVI.63.6.2492-2496.1989

Publication

Journal of virology
ISSN: 0022-538X
NlmUniqueID: 0113724
Country: United States
Language: English
Volume: 63
Issue: 6
Pages: 2492-2496

Researcher Affiliations

Carpenter, S
  • Laboratory of Persistent Viral Diseases, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840.
Chesebro, B

    MeSH Terms

    • Animals
    • Cell Line
    • Cells, Cultured
    • Cytopathogenic Effect, Viral
    • Fluorescent Antibody Technique
    • Horses
    • Immunodiffusion
    • Infectious Anemia Virus, Equine / physiology
    • Macrophages / microbiology
    • RNA-Directed DNA Polymerase
    • Virus Replication

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