Caughey, "Mast cell tryptases and chymases in inflammation and host defense," Immunological Reviews, vol.
(1) Prestored cytoplasmic granules: (a) biogenic amines (e.g., histamine), (b) serglycin proteoglycans (e.g., heparin and chondroitin sulphate), (c) serine proteases (tryptases, chymases, and carboxypeptidases), (d) some cytokines (e.g., TNF-[alpha] and VEGFA).
MC-granules contain biogenic amines (histamine and, only in rodents, serotonin), serglycin proteoglycans (heparin and chondroitin sulphate), serine proteases (tryptases, chymases
, and carboxypeptidases), cytokines (such as TNF-[alpha]), and growth factors (such as vascular endothelial growth factor A (VEGFA)) .
Second, inhibition of angiotensin II by ACE blockade can be bypassed by chymases
. Third, in addition to the classical angiotensin II-dependent effects on natrium retention, blood pressure, induction of thirst, and others, angiotensin II also acts on the release mechanisms of renin, thereby forming a feedback inhibition of the system (Figure 1).
Dipeptidyl peptidase I is essential for activation of mast cell chymases
, but not tryptases, in mice.
In the present study, we co-cultured myocardial microvascular endothelial cells (MMVECs) with MCs to study 1) whether MC granules (MCGs) can promote angiogenesis in MMVECs, 2) how tryptase and chymase play a role in modulating MC-induced neovessel maturation, and 3) whether co-culturing MMVECs with MCs leads to stimulation of Ang-Tie-2 signaling.
Tryptase and chymase enzyme activity in the MCG preparation was measured as described previously (17).
[MC.sub.T] cells containing mainly tryptase are predominantly located in the respiratory and intestinal mucosa, while [MC.sub.TC] cells, expressing both tryptase and chymase, are predominantly found in connective tissues of skin, conjunctiva, and synovia (28,29).
Mast cell chymase and tryptase in abdominal aortic aneurysm formation.