Phenotypic analysis of cells in bronchoalveolar lavage fluid and peripheral blood of maedi visna-infected sheep.

A phenotypic analysis of bronchoalveolar lavage fluid (BALF) and peripheral blood (PB) cells in maedi visna virus (MVV)-infected sheep has been performed. The differential cell count in BALF from MVV-infected animals was characterized by a significant increase (P< 0.05) in lymphocytes and neutrophils. Lymphocyte phenotyping in BALF from MVV-infected sheep showed a significant decrease (P<0.05) or CD4+ cells, a significant increase (P<0.05) of CD8+ cells and a significant inversion (P<0.00l) of the CD4+ /CD8+ ratio. CD5 + lymphocytes were also significantly decreased (P<005). γλ T cells and B cells did not differ significantly when compared with the controls. No correlation was observed between BALF and PB lymphocyte phenotypes. BALF macrophages from MVV-infected animals showed increased MHC class II expression and BALF lymphocytes from the same animals demonstrated up-regulation of LFA-1 and LFA-3 expression. These findings and their relationship with lentiviral pathogenesis are discussed. [ABSTRACT FROM AUTHOR]