EXPERIMENTAL MODEL OF LENTIVIRUS REACTIVATION FOR VIROLOGICAL AND IMMUNOLOGICAL STUDIES IN CAPRINE ARTHRITIS-ENCEPHALITIS VIRUS (CAEV) INFECTED GOATS

摘要

It has recently been shown that patients with well-controlled Human Immunodeficiency Virus type 1 (HIV-1) infections (non-progressors) have a vigorous polyclonal cytotoxic T lymphocyte (CTL) response to viral antigens, which contributes to viraemia control, whereas progressor patients do not. To determine whether a similar mechanism regulates the blood proviral load in goats chronically infected with Caprine Arthritis Encephalitis Virus (CAEV), we developed an experimental model of viral reactivationto follow the evolution of virological and immunological parameters. CAEV replication was stimulated in two goats by hormonally inducing lactation, and proviral load and CTL responses in blood were monitored. Proviral load, measured weekly by the semi-quantitative nested PCR infectious centre assay, began to rise 20 d post induction (pi) in both animals to reach a maximum of 17 infected peripheral blood mononuclear cell (PBMC)/10~6 at day 27 pi. A rapid drop in blood proviral load then occurred in bothanimals, and was undetectable by two months pid. One of the two goats had a strong CTL response to autologous CAEV-infected cells, which occurred in parallel with the rapid drop of the blood proviral load. These results present an original model for analysis of relationship between virological and immunological parameters during CAEV infection.