Virus dynamics and antibody escape in equine infectious anemia virus (EIAV) infection

Friday, April 19, 2019 - 1:30pm


Elissa Schwartz
Associate Professor
Department of Mathematics and Statistics
Washington State University


Understanding the dynamics of acute viral infection is crucial for developing strategies to prevent and control infection. Lentiviral dynamics in a host without adaptive immunity were examined in order to determine kinetic parameters of infection and quantify the effect of neutralizing antibodies in preventing infection, using mathematical modeling of data from equine infectious anemia virus (EIAV) infection of horses with severe combined immunodeficiency (SCID). Estimated parameters were used to calculate the basic reproductive number and virus doubling time and found that the rate that antibodies neutralized virus was nearly 18 times greater than the virus clearance rate. Our results establish EIAV replication kinetics in SCID horses and the minimal efficacy of antibodies that blocked infection. Furthermore, they indicate that EIAV is at most mildly cytopathic. We also quantified antibody escape of EIAV, using antibody escape data from horses infused before infection with either plasma containing neutralizing antibodies (NAbs) from a persistently infected immunocompetent horse or plasma from uninfected normal controls. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization as well as in the development of NAb-eliciting vaccine strategies.