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

Since the percutaneous transtuminal coronary angioplasty was introduced into China in 1984, this procedure has become widely accepted as an important step in coronary revascularization. This study shows the effect of the monoclonal antibody (mAb) on the platelet glycoprotein IIIa receptor during endothelialization and in-stent restenosis by implanting the mAb-eluting stents into iliac arteries of rabbits. The hard tissue cross sections of the stent-implanted arterial segments were made by polymethylmethacrylate embedding. Arterial intima proliferation was observed and analyzed. The endothelialization of the stent surface was observed using scanning electron microscope, whereas the ultrastructure of the neointima was observed using transmission electron microscope. After one month of stent implantation, the surfaces of both groups were covered by intact endothelial layers, but the neointimal areas and the ratio of stenosis were significantly lesser in the mAb-eluting stent group (p < 0.01). After 3 months, the ratio of stenosis in the mAb-eluting stent group was 14.67 ± 0.79, whereas that of the bare stent group was 21.58 ± 1.76 (p < 0.01). Therefore, the mAb eluting from the stent surface has the potential to accelerate endothelialization, prevent thrombosis formation due to the interaction of stent with blood, and decrease the stenosis ratio by inhibiting neointima proliferation.

[The protection of elemene on injured HUVECs induced by hydrogen peroxide].

OBJECTIVE: To evaluate the effect of elemene on the survival of normal human umbilical endothelial cells (HUVECs) and the protection of elemene on injured HUVECs induced by hydrogen peroxide (H2O2). METHODS: Normal HUVECs were treated with elemene 1-100 microg/ml for 24-72 hours, the survival rate of HUVECs was determined by tetrazolium assay (MTT). To evaluate the protective effect of elemene on HUVECs from H2O2 injury, HUVECs were injured by 1 mmol/L H2O2 and then different final concentrations of elemene were added before the injury. After culturing 1 hour, then detecting the index of MDA, T-AOC, SOD, CAT, GSH-Px and NO. RESULTS: Elemene could inhabit the proliferation of VEC and it presented dose-dependent, while on the side of anti-oxidization injury, it also presented dose-dependent. MDA content and the effect of H2O2 to antioxidase activity were decreased, NO content in cell was increased, and the amount of apoptosis was reduced. CONCLUSION: Elemene has dual effects on the survival rate of normal HUVECs in vitro, which is related to the concentration and the duration of drug exposure. Elemene has protective effects on the injured endothelial cells injured by oxidization through the function of anti-lipid oxidization.

[In vitro study of platelet glycoprotein monoclonal antibody eluting stents].

In order to prove the feasibility of preparation of the drug-incorporated stent by immersing stent wires in the monoclonal antibody (mAb) solution, fluorescence stain and image analysis were used to evaluate the L-PLA-coated stent. Absorption was measured using a radioisotope technique after preparing the mAb-incorporated stent, and the absorption curve was determined from the absorption data. In an in vitro perfusion circuit, the antibody was eluted from the stent matrices, and the related influence factors were evaluated based on the release data.

[Development of drug coating on drug eluting stents].

Researches on drug-eluting stents are now focusing on three main aspects: the stent materials, the coating matrix material and the selection, adhesion and controlled release of the biological agents. The current development progresses of the coating materials, their characteristics, and the coating method for metallic stents are reviewed in this paper.