The role of antibody during ovine lentivirus disease in experimentally infected sheep

Infection of sheep by Ovine Lentivirus (OvLV) is a significant disease throughout the world, with the exception of Australia and New Zealand.

In this study, the sera of four experimentally infected sheep were analysed over a two-year time period, with respect to neutralizing antibody (NT-Ab) titres and non-neutralizing ELISA antibodies against both the whole virus and the immuno-dominant recombinant proteins; capsid (CA), and trans-membrane peptide (TM). It was hypothesised that a further mechanism of persistence of OvLV may be mediated by interference of non-neutralizing antibodies with neutralizing antibody via conformational change of viral surface envelope proteins, which contain Nt-Ab epitopes. The postulated phenomenon of virus-obstructing antibody activity was investigated by analysis of correlation between neutralizing and non-neutralizing antibody responses (i.e. vs capsid/transmembrane), as well as by a neutralizing assay where high and low neutralizing antibody titre sera were analysed in a 1:1 mixture.

The report of an IgG, restricted antibody response in OvLV infection was investigated. (Abstract shortened by UMI.).