Platelet adhesion to radiofrequency glow-discharge-deposited fluorocarbon polymers preadsorbed with selectively depleted plasmas show the primary role of fibrinogen

Abstract

Fluorocarbon radio-frequency glow-discharge (RFGD) treatment has previously been shown to cause decreased platelet adhesion despite the presence of adsorbed fibrinogen on the surfaces. In this study platelet adhesion to fluorocarbon RFGD-treated surfaces preadsorbed with human plasma was further examined. A series of plasma deposited fluorocarbon thin films were made by varying the C3F6/CH4 ratio in the monomer feed. The surfaces were preadsorbed with plasma, serum, or plasma selectively depleted of fibronectin, vitronectin, or Von Willebrand factor, and platelet adhesion was measured. We also measured fibrinogen adsorption to the surfaces from plasma, monoclonal antibody binding to adsorbed fibrinogen and SDS elutability of the adsorbed fibrinogen. The antibodies used bind to the three putative platelet binding sites on fibrinogen, namely, M1 antibody binds to the dodecapeptide at the C-terminus of the gamma chain, gamma (402-411), R1 antibody binds to a sequence in the Aalpha chain (87-100) which includes RGDF at Aalpha (95-98) and R2 antibody binds a sequence in the Aalpha chain (566-580) which includes RGDS at Aalpha (572-575). Fibrinogen was found to play a decisive role in mediating platelet adhesion to the fluorocarbon surfaces contacting plasma. Few platelets adhered to the fluorocarbon surfaces preadsorbed with serum, while preadsorption with plasma selectively-depleted of either fibronectin, vitronectin, or von Willebrand factor did not decrease platelet adhesion significantly. Replenishment of exogenous fibrinogen to serum restored platelet adhesion, while replenishment of the other proteins had no effect. Platelet adhesion to the fluorocarbon surfaces was lower than to PET or the methane glow-discharge-treated PET. However, there was no apparent correlation between platelet adhesion and the amount of fibrinogen adsorption or monoclonal antibody binding to surface-bound fibrinogen.

Heparin-like surface modification of polyethersulfone membrane and its biocompatibility

“…Fibrinogen is the major protein adsorbed, and many other plasma proteins, including albumin and gammaglobulin, are also adsorbed [15]. The amount of proteins adsorbed on the material surface is reported to be one of the important factors in evaluating the blood compatibility of materials [36,37]. There are many factors affecting the interaction between membrane surface and protein, such as surface charged character, surface free energy and topological structure, solution environment (e.g.…”

Fibrinogen adsorption, platelet adhesion and activation on mixed hydroxyl-/methyl-terminated self-assembled monolayers

“…All of these plasma adhesion proteins contain the cell-binding sequence RGD and can bind platelets via specific cell membrane receptors. However, recent studies suggest that fibrinogen is the major plasma protein that mediates platelet adhesion to artificial surfaces pre-immersed in plasma [2,22]. During the present study, platelet adhesion and activation was evaluated on SAMs possessing different wettabilities, with and without pre-immersion in fibrinogen, albumin and plasma (1%).…”

Non-fouling biomaterials based on blends of polyethylene oxide copolymers and polyurethane: simultaneous measurement of platelet adhesion and fibrinogen adsorption from flowing whole blood

“…The adsorbed protein layer is a key factor in these phenomena and four proteins in particular, namely fibrinogen [25], fibronectin [26,27], vitronectin [25][26][27], and von Willebrand factor [28] have been shown to be involved in mediating cell adhesion in general and platelet adhesion in particular.…”