Goat uterine epithelial cells are susceptible to infection with Caprine Arthritis Encephalitis Virus (CAEV) in vivo

Caprine arthritis-encephalitis virus (CAEV) was first described as a cause of chronic arthritis in American goats [1-3], and has since been found to be widespread in goat herds worldwide [4,5]. CAEV is an RNA virus belonging to the lentivirus genus of the family retroviridae [1]. In France, the infection is present in around 80 to 95% of breeding herds [6] and causes economic losses through reduced milk production, early culling, and loss of export potential [7]. Symptoms of infection may include lung disease and, more often, indurative mastitis as well as classical arthritis. Leucoencephalitis in young kids [1] remains rare.Infection can be transmitted by any means involving the transfer of infected cells to a na？ve recipient. In the field, the principal route of transmission is vertical from dam to kids through colostrum and milk [5], with additional horizontal transmission following prolonged contact between infected and na？ve adult animals [8]. Attempts to reduce infection by treating colostrum and milk, and separating infected and na？ve animals have been disappointing [8,9], and attempts have been made to identify other risk factors [10,11].Although the oral route remains the principal mode of natural transmission, sexual transmission has yet to be fully explored. CAEV proviral DNA has been identified using PCR in tissues of the genital tract (uterus, oviduct, and ovary [12]), and in uterine flushing media recovered four days after fecundation [13,14].The virus primarily infects cells of the monocyte-macrophage lineage, with viral production being linked to cell differentiation from monocytes to macrophages [15,16]; however, viral transcripts have been detected in epithelial cells in the small intestine, thyroid gland, and kidneys of infected goats [17]. In vitro, granulosa cells, oviduct epithelial cells [18,19] and caprine early embryonic cells [20] are susceptible to CAEV infection, and infection with this virus is productive. Nevertheless, no information is