[HTML][HTML] Dipeptidyl peptidase I is essential for activation of mast cell chymases, but not tryptases, in mice
Dipeptidyl peptidase I (DPPI) is the sole activator in vivo of several granule-associated
serine proteases of cytotoxic lymphocytes. In vitro, DPPI also activates mast cell chymases
and tryptases. To determine whether DPPI is essential for their activation in vivo, we used
enzyme histochemical and immunohistochemical approaches and solution-based activity
assays to study these enzymes in tissues and bone marrow-derived mast cells (BMMCs)
from DPPI+/+ and DPPI−/− mice. We find that DPPI−/− mast cells contain normal amounts of …
serine proteases of cytotoxic lymphocytes. In vitro, DPPI also activates mast cell chymases
and tryptases. To determine whether DPPI is essential for their activation in vivo, we used
enzyme histochemical and immunohistochemical approaches and solution-based activity
assays to study these enzymes in tissues and bone marrow-derived mast cells (BMMCs)
from DPPI+/+ and DPPI−/− mice. We find that DPPI−/− mast cells contain normal amounts of …