Perivascular inflammatory cells in ovine Visna/maedi encephalitis and their possible role in virus infection and lesion progression.
We examined the distribution in the perivascular spaces of Visna/maedi antigen, T cells (CD3+, CD4+ and CD8+), B cells and macrophages by immunohistochemistry in 22 natural cases of Visna/maedi encephalitis. Sheep showed lymphocytic or histiocytic lesions. In mild lymphocytic lesions, the viral antigen was detected in perivascular cuffs where CD8+ T cells predominated, but in severe lymphocytic lesions, sparse antigen was identified, and CD8+/CD4+ T cells appeared in a similar proportion in multilayer perivascular sleeves. In histiocytic lesions, vessels were surrounded by macrophages with abundant viral antigen, with CD8+/CD4+ T cells and B cells in the periphery. These results could reflect different stages of virus neuroinvasion and clarify the neuropathogenesis of Visna/maedi encephalitis.
Pathological Anatomy Section, Animal Health Department, Veterinary School, University of León, 24007, León, Spain. lpolr@unileon.es
Laura
L
Polledo
Jorge
J
González
Julio
J
Benavides
Beatriz
B
Martínez-Fernández
Ma Carmen
MC
Ferreras
Juan F García
JF
Marín
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology*; D001808:Blood Vessels / Q000276:immunology / Q000473:pathology*; D001921:Brain / Q000276:immunology / Q000473:pathology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology*; D018792:Encephalitis, Viral / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008264:Macrophages / Q000276:immunology / Q000473:pathology*; D012756:Sheep; D034561:Sheep, Domestic; D016182:Visna / Q000276:immunology / Q000473:pathology*; D014790:Visna-maedi virus / Q000276:immunology
D000956:Antigens, Viral