Immunohistochemical quantification of granulocytes in the lung. Granulocytes in the lung sections were stained using anti-granulocyte antibody from control (A, arrows and inset), E. coli LPS (B), one day (C-D) exposed rats without and with E. coli LPS challenge and five day (E) barn exposed rats without (arrows, B-E) and with E. coli LPS challenge (picture not shown) respectively. F: Quantification of septal granulocytes showed increased numbers in one day exposed rats with E. coli LPS challenge compared to one day exposed rats without E. coli LPS challenge (P = 0.029). Five day exposed rats with E. coli LPS challenge show a trend towards significant increase when compared to respective five day exposed rats without E. coli LPS challenge (F, P = 0.051). Original magnification A-F: ×400 and micrometer bar = 50 μm.