MEMORY AND CD8(+) ARE THE PREDOMINANT BOVINE BRONCHOALVEOLAR LYMPHOCYTE PHENOTYPES

Bovine lymphocytes obtained by bronchoalveolar lavage (BAL) of healthy calves were simultaneously analyzed and compared to peripheral blood lymphocytes using monoclonal antibodies specific for bovine leukocyte differentiation antigens. Phenotypic differences were observed between bronchoalveolar and peripheral blood T-lymphocyte subpopulations, dem onstrating selective lymphocyte migration to the bovine lung. The bron choalveolar and peripheral blood T-lymphocyte populations, defined by expression of CD2, were similar, but bronchoalveolar T lymphocytes wer e predominately CD8(+) while peripheral blood T cells were predominate ly CD4(+) In addition, memory lymphocytes, characterized by low expres sion of CD45R and activated lymphocytes (CD25(+)), were found in signi ficantly higher proportions in the bronchoalveolar compartment. The pr oportion of gamma delta T lymphocytes was, however, significantly high er in peripheral blood. B cells were observed in similar proportions i n the bronchoalveolar compartment and peripheral blood. (C) 1997 Elsev ier Science B.V.