passages.id: split_6_test_1992_passage
passages.type: progene_text
passages.text: Therefore , the number of proliferating macrophages , dendritic cells , natural killer cells and T and B lymphocytes was studied during acute otitis media in the rat middle ear mucosa ( ME mucosa ) and Eustachian tube mucosa ( ET mucosa ) by labelling proliferating leucocytes with the DNA precursor bromodeoxyuridine ( BrdU ) .