Journal
JOURNAL OF LEUKOCYTE BIOLOGY
Volume 78, Issue 2, Pages 453-461Publisher
WILEY
DOI: 10.1189/jlb.1004566
Keywords
activated complement C3; molecular weight; orosomucoid; subcellular localization; secretion; specific granules; azurophilic granules
Categories
Ask authors/readers for more resources
alpha(1)-Acid glycoprotein (AGP) is a major acute-phase protein present in human plasma as well as in polymorphonuclear leukocytes (PMN). In this report, we show that PMN synthesize a specific glycoform of AGP, which is stored in the specific and azurophilic granules. Activation of PMN results in the rapid release of soluble AGP. PMN AGP exhibits a substantially higher apparent molecular weight than plasma AGP (50-60 kD vs. 40-43 kD), owing to the presence of strongly fucosylated and sialylated polylactosamine units on its five N-linked glycans. AGP is also released in vivo from activated PMN, as appeared from studies using well-characterized myocard slices of patients that had died within 2 weeks after an acute myocardial infarction. AGP was found deposited transiently on damaged cardiomyocytes in areas with infiltrating PMN only. It is interesting that this was inversely related to the deposition of activated complement C3. Strongly fucosylated and sialylated AGP glycoforms have the ability to bind to E-selectin and to inhibit complement activation. We suggest that AGP glycoforms in PMN provide an endogenous feedback-inhibitory response to excessive inflammation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available