Activation of small ruminant aortic endothelial cells after in vitro infection by caprine arthritis encephalitis virus

Small ruminants infected by the lentiviruses caprine arthritis-encephalitis virus (CAEV), originally isolated from a goat, or maedi-visna virus, origi nally from sheep, typically develop an oganising lymphoid infiltration of a ffected tissues. This could reflect modulation of the migration pattern of lymphocytes in infected animals. Possible active contribution by vascular e ndothelial cells was investigated using an in vitro model. Low-passage cult ured ovine aortic endothelium proved susceptible to productive infection by CAEV without significant cytotoxicity. Infected endothelial cells maintain ed expression of endothelial markers, increased MHC class I antigen express ion and initiated expression of the adhesion molecule VCAM-1 and, at a late stage, MHC class II antigens. Infected endothelial cells showed a two-fold increase in binding capacity for sheep peripheral blood leucocytes over un infected controls. Such events could contribute to the tissue distribution of lymphoid cells and local immune responses in lentiviral infections of sm all ruminants. (C) 2000 Harcourt Publishers Ltd.