AJP - Lung Cellular and Molecular Physiology, Vol 260, Issue 2 153-L160, Copyright © 1991 by American Physiological Society
Heterogeneity of intact granules purified from canine mastocytoma cell lines
P. S. Thomas, R. E. Schreck, S. J. Ruoss and S. C. Lazarus
Cardiovascular Research Institute, University of California, San Francisco 94143.
We investigated the observation that some mast cells exhibit asynchronous
release of granule-associated neutral proteases. Intact mast cell granules
were isolated, purified, and studied with respect to their histamine,
neutral protease, and proteoglycan content. Studies of two canine
mastocytoma cell lines demonstrated differences in storage and packaging of
granules within one of the cell lines (G) with respect to the neutral
proteases and density, resulting in two distinct subpopulations of
granules. By use of identical techniques no such differences were found in
the other cell line (BR). These observations suggest that granule
subpopulations in some mast cells may have a role in the differential
release of mediators.
