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Platelet Factor 4 Binds to Vascular Proteoglycans and Controls Both Growth Factor Activities and Platelet Activation.

ABSTRACT: Platelet factor 4 (PF4) is produced by platelets with roles in both inflammation and wound healing. PF4 is stored in platelet ?-granules bound to the glycosaminoglycan (GAG) chains of serglycin. This study revealed that platelet serglycin is decorated with chondroitin/dermatan sulfate and that PF4 binds to these GAG chains. Additionally, PF4 had a higher affinity for endothelial-derived perlecan heparan sulfate chains than serglycin GAG chains. The binding of PF4 to perlecan was found to inhibit both FGF2 signaling and platelet activation. This study revealed additional insight into the ways in which PF4 interacts with components of the vasculature to modulate cellular events.

SUBMITTER: Lord MS

PROVIDER: S-EPMC5354495 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Platelet Factor 4 Binds to Vascular Proteoglycans and Controls Both Growth Factor Activities and Platelet Activation.

Lord Megan S MS Cheng Bill B Farrugia Brooke L BL McCarthy Simon S Whitelock John M JM

The Journal of biological chemistry 20170123 10

Platelet factor 4 (PF4) is produced by platelets with roles in both inflammation and wound healing. PF4 is stored in platelet α-granules bound to the glycosaminoglycan (GAG) chains of serglycin. This study revealed that platelet serglycin is decorated with chondroitin/dermatan sulfate and that PF4 binds to these GAG chains. Additionally, PF4 had a higher affinity for endothelial-derived perlecan heparan sulfate chains than serglycin GAG chains. The binding of PF4 to perlecan was found to inhibit ...[more]

PMID: 28115521

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