Sialic Acid Dependent and Independent Effects of alpha 1-Acid Glycoprotein (AGP) on Human Platelets
2008 (English)In: 2008 Meeting of the Society for Glycobiology, 2008, Vol. 18, no 11, 990-990 p.Conference paper (Other academic)
Objective: We have recently shown that terminal sialic acid residues are essential for α1-acidglycoprotein (AGP)-induced Ca2+ mobilization in neutrophils. The aim of the present studywas to establish the importance of sialic acid-residues on AGP in modulating humanneutrophil functions, with emphasis on the generation of reactive oxygen species (ROS).Material and methods: ROS were measured by luminol-enhanced chemiluminescence inisolated human neutrophils.
Results: We found that AGP did not provoke ROS generation in resting or L-selectin presensitizedneutrophils. Moreover, AGP did not affect the N-formyl-methionyl-leucylphenylalanine(fMLP)-induced ROS generation but it slightly suppressed opsonized zymosaninducedresponses. However, when the neutrophils were pre-stimulated with fMLP, thefollowing addition of AGP provoked a marked ROS response. Dose-response studies and timestudies revealed that the ROS generating capacity of AGP was maximal at a concentration of0.05 mg/ml and when given 3-10 min after addition of fMLP. A desialylated form of AGP orpre-treatment of neutrophils with 3’- and 6’-sialyllactose caused a substantial lower ROSresponse in neutrophils pre-stimulated with fMLP.
Conclusions: Our data show that AGP can stimulate a second ROS response in fMLP preactivatedneutrophils and that terminal sialic acid residues on AGP play a crucial role in thisregard.
Place, publisher, year, edition, pages
2008. Vol. 18, no 11, 990-990 p.
α1-acid glycoprotein, neutrophils, reactive oxygen species, sialic acid
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-16353OAI: oai:DiVA.org:liu-16353DiVA: diva2:133970