Immune response in rabbit ovaries following infection of a recombinant myxoma virus expressing rabbit zona pellucida protein B.

In this study, we investigated the autoimmune response in rabbit ovaries following infection with a recombinant myxoma virus expressing rabbit zona pellucida protein B (MV-ZPB). A specific IgG antibody response to ZPB was elicited in the serum of infected rabbits and the antibody strongly bound to the zona pellucida of oocytes in secondary and tertiary follicles. T cell infiltration in the ovary was detected in a small proportion of the infected rabbits. In spite of this, the mean number of preovulatory and tertiary follicles in the ovary was significantly reduced at 30 days postinfection compared with that of the infected and uninfected controls. Histological analysis revealed that the cortex and medulla of these ovaries had accumulated a large number of probably luteinized cells and there were no follicles in these areas, indicating the ovaries were in a severe pathological condition. The data suggest that the delivery of ZP antigens using a recombinant myxoma virus is a prospective way to develop immunocontraceptive vaccines for rabbit population control, but that more understanding of the kinetics of the autoimmune response induced by viral delivery is needed.