Immunogenicity and protective activity of four cell-based feline immunodeficiency virus (FIV) vaccines prepared with autologous lymphoblasts were investigated. One vaccine was composed of FIV-infected cells that were paraformaldehyde fixed at the peak of viral expression. The other vaccines were attempts to maximize the expression of protective epitopes that might become exposed as a result of virion binding to cells and essentially consisted of cells mildly fixed after saturation of their surface with adsorbed, internally inactivated FIV particles. The levels of FIV-specific lymphoproliferation exhibited by the vaccinees were comparable to the ones previously observed in vaccine-protected cats, but antibodies were largely directed to cell-derived constituents rather than to truly viral epitopes and had very poor FIV-neutralizing activity. Moreover, under one condition of testing, some vaccine sera enhanced FIV replication in vitro. As a further limit, the vaccines proved inefficient at priming animals for anamnestic immune responses. Two months after completion of primary immunization, the animals were challenged with a low dose of homologous ex vivo FIV. Collectively, 8 of 20 vaccinees developed infection versus one of nine animals mock immunized with fixed uninfected autologous lymphoblasts. After a boosting and rechallenge with a higher virus dose, all remaining animals became infected, thus confirming their lack of protection.
|Autori interni:||MATTEUCCI, DONATELLA|
|Autori:||GIANNECCHINI S; ISOLA P; SICHI O; MATTEUCCI D; PISTELLO M; ZACCARO L; DEL MAURO D; BENDINELLI M|
|Titolo:||AIDS vaccination studies using an ex vivo feline immunodeficiency virus model: Failure to protect and possible enhancement of challenge infection by four cell-based vaccines prepared with autologous lymphoblasts|
|Anno del prodotto:||2002|
|Digital Object Identifier (DOI):||10.1128/JVI.76.14.6882-6892.2002|
|Appare nelle tipologie:||1.1 Articolo in rivista|