Assessment of cellular profile and lung function with repeated bronchoalveolar lavage in individual mice

In this study, we sought to develop procedures that would enable repeated b ronchoalveolar lavage (BAL) in individual mice on multiple occasions. To ac hieve this objective, we first developed the procedures that would allow in dividual mice to survive a whole lung lavage, and then tested whether, on s ubsequent days, there was an effect of this initial BAL on the cell profile , lung permeability, and baseline respiratory function. Our results demonst rate that the repeated lavage procedure can be readily carried out in indiv idual mice of different strains on multiple occasions. The lavage procedure itself results in immediate increases in respiratory system resistance and concomitant decreases in compliance, but these parameters return to prelav age values by the 2nd or 3rd day postlavage. Lavage also induces variable i ncreases in inflammatory cells depending on the strain used. However, in al l three strains examined here (A/J, BALB/c, and C3H/HeJ), inflammatory cell numbers returned to baseline values within 3 days after an initial lavage procedure. The ability to perform repeated BAL in individual mice should pr ove to be an extremely useful tool in a variety of functional genomic studi es in the lung.