Alteration of alveolar macrophage functions after aerosol infection with bovine herpesvirus type 1.

Calves were aerosol challenged with bovine herpesvirus type I, and bronchoalveolar cells were subsequently retrieved by lavage from days 1 to 8 postinfection. Alveolar macrophages (AM), which were depleted of contaminating cells, were characterized with respect to phenotypic markers and functional activities. In most aspects, the changes suggested a stimulation of the AM. With variations in kinetics the percentage of AM expressing an MHC II antigen and Fc (immunoglobulin G)-mediated phagocytosis increased, as did the activity level of two ectoenzymes and the lysosomal hydrolase beta-glucoronidase. The generation of prostaglandin E2 by the AM also rose significantly. However, selective suppression of cellular cytotoxicity and interleukin-1 generation was observed. These findings may have important implications for understanding the events involved in the virus-bacterial interaction in respiratory diseases.