@entity46655 ) is a prototypic lentivirus that causes @entity281 only in cells of macrophage lineage, unlike the primate lentiviruses which infect both @entity18729 + T lymphocytes and macrophages. In primates, the earliest viral invasion is associated with the ability of the virus to infect and activate T cells which convey virus to the brain. Infected monocytes in blood rarely cause @entity281 in absence of activation of @entity18729 + T cells. In the face of lack of @entity281 or activation of T cells by MVV in @entity742 , the question arises, how does MVV gain access to the brain to cause the @entity75 ? In previous studies on experimental induction of visna, @entity742 were inoculated with virus directly in the brain. In this study, we asked whether neuroinvasion by MVV would occur if @entity742 were inoculated with virus in a non-neural site. Nine @entity742 were inoculated intratracheally and all developed @entity281 when examined 3 weeks later. At this time, five were injected intramuscularly with brain white matter homogenized in Freund's complete adjuvant to induce EAE. None of the four animals inoculated with virus alone developed @entity281 despite typical @entity281 in lungs, lymphoid tissues and blood-borne mononuclear cells. In contrast, all five of the @entity742 injected with brain homogenate developed @entity281 in the brain. Virus was produced by macrophages associated with the @entity75 . This study illustrated that both activated T cells specific for antigen in the CNS and infected macrophages are essential for lentivirus neuropathogenesis.

Neuroinvasion by ovine lentivirus in infected XXXX mediated by inflammatory cells associated with experimental allergic encephalomyelitis.

@entity46655 :: ('11741', 'Species') :: ['Maedi Visna Virus (MVV'] @entity742 :: ('9940', 'Species') :: ['sheep'] @entity18729 :: ('443509(Tax:9940)', 'Gene') :: ['CD4'] @entity75 :: ('MESH:D001927', 'Disease') :: ['classical lesions of visna', 'EAE lesions'] @entity281 :: ('MESH:D007239', 'Disease') :: ['CNS infection', 'infection', 'systemic infection', 'lentiviral infection']
@entity742 :: (9940,Species) :: ['sheep']
