Eluting characteristics of a platelet glycoprotein receptor antibody using a PLLA-coated stent

Abstract

Drug-eluting stents (DES) have emerged as a recognized alternative to treat stent restenosis but many questions remain regarding the optimal type and eluting characteristics of both drug and stent. The first component of the study examines the extent of surface coating of PLLA (poly(L-lactic acid)) on a Nitinol stent. The second characterizes the adsorption and elution rates of monoclonal mouse anti-human platelet glycoprotein (GP) IIIa antibody SZ-21 from a PLLA-coated surface. The PLLA coating was examined by fluorescence staining and image analysis using the Image Processing Box of MATLAB. Stents exposed to the monoclonal mouse anti-human platelet GP IIIa antibody were tested for their adsorption characteristics by radioisotope technique with (125)I-labelled SZ-21. The elution rates were then measured in looped circuits at different velocities (10 or 20 ml/min) and durations (30 min up to 312 h). Results showed that the fluorescence staining and image analysis showed a striking difference in the extent of coating between PLLA-coated stents and SZ-21 eluting stents on the gray-scale distribution of Nitinol surfaces. The amount of SZ-21 adsorbed onto the PLLA-coated stents was dependent on the concentration and duration of immersion in the solution. The method of preparation the mAb eluting stent significantly influenced the elution characteristics for a continuous perfusion of more than 300 h. The eluting curve was biphasic with initial rapid elution for the first 24 h followed by a gradual slow elution. These results indicate that the Image Processing Box of MATLAB appears to be a useful method for semi-quantitative analysis of fluorescence images. Furthermore, SZ-21 can be passively adsorbed onto PLLA-coated stents and predictably influenced by the concentration and duration of immersion. These studies may pave the way to developing stent-based delivery of a potent anti-platelet agent.

Amphiphilic diblock copolymers containing poly(N‐hexylisocyanate): Monolayer behavior at the air–water interface

“…The adsorption characteristics of the stents exposed to the mAb were tested by radioisotope technique with 125 I‐labelled SZ‐21. The elution rates were then measured in looped circuits at different velocities and durations 15. The mAb‐eluting stents were produced by immersing the PLLA‐coated stents in a 2.0 mg/mL solution of SZ‐21 antibody at 37°C.…”

“…The authors' previous studies have demonstrated that SZ‐21 could effectively inhibit platelet aggregation and the eluting characteristics of the platelet when eluted from L ‐polylactic acid (PLLA) polymer‐coated stents prepared by a special stent‐coating system in vitro 13–15. In this study, mAb is applied to the platelet glycoprotein IIIa receptor as the eluting drug of PLLA polymer‐coated stents, and passive absorption method is used to produce mAb‐eluting intravascular stents.…”

Endothelialization and in‐stent restenosis on the surface of glycoprotein IIIa monoclonal antibody eluting stent

“…The elution rates were then measured in looped circuits at different velocities and durations. 15 The mAb-eluting stents were produced by immersing the PLLA-coated stents in a 2.0 mg/mL solution of SZ-21 antibody at 37 C. After passive absorption for 72 h, the quantity of SZ-21 absorbed on the stent wires was 0.8 mg/cm 2 . An in vitro perfusion circuit was designed to evaluate the release rates at different velocities (10 or 20 mL/min).…”

“…12 The authors' previous studies have demonstrated that SZ-21 could effectively inhibit platelet aggregation and the eluting characteristics of the platelet when eluted from L-polylactic acid (PLLA) polymer-coated stents prepared by a special stent-coating system in vitro. [13][14][15] In this study, mAb is applied to the platelet glycoprotein IIIa receptor as the eluting drug of PLLA polymer-coated stents, and passive absorption method is used to produce mAb-eluting intravascular stents. This study focuses on the inhibitory effect of this stent on stent thrombosis, neointimal hyperplasia, and in-stent restenosis by implanting mAb-eluting stents into iliac arteries of rabbits.…”