DIFFERENTIAL CELL ANALYSIS AND PHENOTYPIC SUBTYPING OF LYMPHOCYTES INBRONCHOALVEOLAR LAVAGE FLUID FROM CLINICALLY NORMAL DOGS

In 33 healthy dogs, 66 bronchoalveolar lavage samples from the right a nd left caudal lung lobes were analyzed for volume of return, cellular ity, differential cellularity, and immunophenotypic lymphocyte subpopu lations. Lavage return was 64.8% (mean) following 3 sequential 25-ml l avages, for a total lavage volume of 75 ml. With this technique, 21.1 X 106 cells/sample (mean) were obtained. The cellular components of br onchoalveolar lavage samples, in decreasing order of frequency, were a lveolar macrophages (79.4%), lymphocytes (13.5%), eosinophils (3.6%), mast cells (2.1%), epithelial cells (0.8%), and neutrophils (0.6%). Me an alveolar lymphocyte subpopulation frequencies, determined in 18 sam ples, for pan T, CD4, and CD8 cells were 52, 21.9, and 17.8%, respecti vely, with a CD4/CD8 ratio of 1.3. Variables analyzed did not vary bet ween right and left caudal lung lobes, nor were they affected by body weight.