TY - JOUR T1 - Species-Specific Humoral Immune Responses in Sheep and Goats upon Small Ruminant Lentivirus Infections Inversely Correlate with Protection against Virus Replication and Pathological Lesions. JF - Int J Mol Sci Y1 - 2021 A1 - Rodolphe Michiels A1 - S. Roels A1 - Nick Vereecke A1 - Elisabeth Mathijs A1 - Laurent Mostin A1 - Nick De Regge KW - Animals KW - Antibodies, Viral KW - Arthritis-Encephalitis Virus, Caprine KW - Female KW - Genotype KW - Goat Diseases KW - Goats KW - Immunity, Humoral KW - Lung KW - Mammary Glands, Animal KW - Pneumonia, Progressive Interstitial, of Sheep KW - Sheep KW - Species Specificity KW - Viral Load KW - Virus Replication KW - Visna-maedi virus AB -

Maedi-Visna-like genotype A strains and Caprine arthritis encephaltis-like genotype B strains are small ruminant lentiviruses (SRLV) which, for incompletely understood reasons, appear to be more virulent in sheep and goats, respectively. A 9-month in vivo infection experiment using Belgian genotype A and B SRLV strains showed that almost all homologous (genotype A in sheep; genotype B in goats) and heterologous (genotype A in goats; genotype B in sheep) intratracheal inoculations resulted in productive infection. No differences in viremia and time to seroconversion were observed between homologous and heterologous infections. Higher viral loads and more severe lesions in the mammary gland and lung were however detected at 9 months post homologous compared to heterologous infection which coincided with strongly increased IFN-γ mRNA expression levels upon homologous infection. Pepscan analysis revealed a strong antibody response against immune-dominant regions of the capsid and surface proteins upon homologous infection, which was absent after heterologous infection. These results inversely correlated with protection against virus replication in target organs and observed histopathological lesions, and thus require an in-depth evaluation of a potential role of antibody dependent enhancement in SRLV infection. Finally, no horizontal intra- and cross-species SRLV transmission to contact animals was detected.

VL - 22 CP - 18 M3 - 10.3390/ijms22189824 ER -