Infection of bone marrow macrophages by equine infectious anemia virus.
OBJECTIVE
To characterize infection of bone marrow-derived macrophages (BMDM) with equine infectious anemia virus (EIAV) by determining virus production, effects on viability, and induction of cytokines.


METHODS
BMDM obtained from bone marrow of 6 clinically normal adult horses.


METHODS
BMDM were infected with EIAV at a multiplicity of infection of 8. Cell viability, percentage of cells with detectable viral protein, reverse transcriptase activity, and concentrations of infective virus (focus-forming units/ml), interleukin 6, and tumor necrosis factor-alpha were measured in culture supernatant samples obtained at various days after infection.


RESULTS
Cell viability was decreased on day 4 and was maximally decreased on day 8. The number of cells with detectable viral protein and supernatant reverse transcriptase activity increased significantly on day 4 and increased until day 6. Virus concentration (focus-forming units per milliliter) peaked on day 4 after infection and was constant thereafter. Infection with EIAV caused significant induction of interleukin 6 production by BMDM. The maximal difference was seen on day 4 after infection. Control and infected BMDM produced only negligible amounts of tumor necrosis factor-alpha.


CONCLUSIONS
BMDM are useful, as a cell population, to study the effects of infection with EIAV, including cell death and induction of interleukin 6 but not tumor necrosis factor-alpha production.
Swardson
C J
CJ
Department of Veterinary Biosciences, College of Veterinary Medicine, Ohio State University, Columbus 43210, USA.
Lichtenstein
D L
DL
Wang
S
S
Montelaro
R C
RC
Kociba
G J
GJ
D000704:Analysis of Variance; D000818:Animals; D001853:Bone Marrow / Q000473:pathology* / Q000821:virology; D002470:Cell Survival; D002478:Cells, Cultured; D003588:Cytopathogenic Effect, Viral; D004859:Equine Infectious Anemia / Q000276:immunology / Q000473:pathology; D006736:Horses; D004860:Infectious Anemia Virus, Equine / Q000502:physiology*; D015850:Interleukin-6 / Q000096:biosynthesis; D008264:Macrophages / Q000378:metabolism / Q000473:pathology / Q000821:virology*; D008854:Microscopy, Electron / Q000379:methods / Q000662:veterinary; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014764:Viral Proteins / Q000378:metabolism; D014771:Virion / Q000302:isolation & purification
D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D014764:Viral Proteins; D012194:RNA-Directed DNA Polymerase