Journal of Applied Physiology, Vol 64, Issue 5 1953-1959, Copyright © 1988 by American Physiological Society
Comparative physiology of rodent pulmonary macrophages: in vitro functional responses
D. B. Warheit, M. A. Hartsky and M. S. Stefaniak
E.I. du Pont de Nemours and Co., Inc., Haskell Laboratory for Toxicology and Industrial Medicine, Newark, Delaware 19714.
Since toxicological testing of inhaled materials frequently requires
utilization of several species, we have investigated pulmonary macrophage
(PM) functional responses and compared the rat model with other rodents.
Two strains of rats, three strains of mice, and one strain each of hamster
and guinea pig were used in this study. The numbers of recovered cells by
bronchoalveolar lavage generally correlated with animal body weight. The
one exception was the Syrian Golden hamster from which increased numbers of
macrophages were recovered. Cellular differential data obtained from
lavaged cytocentrifuge preparations demonstrated that PM's account for
greater than 97% of recoverable free lung cells for all species except the
guinea pig, which contains a resident population of eosinophils. Cell
morphology studies indicated that hamster PM exhibited the highest
proportion of ruffled PM and demonstrated the highest phagocytic activity,
whereas mouse PM phagocytic activity was significantly reduced compared
with the other three species. In addition, chemotaxis studies showed that
rat PM migrated best to zymosan-activated, complement-dependent
chemoattractants, whereas hamster PM demonstrated an enhanced chemotactic
response to N-formyl peptides. The results of these studies suggest that
the rat may be the most efficient species for clearing inhaled particles,
whereas hamsters and guinea pigs may best respond to bacteria.
