Expression, production, and renaturation of a functional single-chain variable antibody fragment (scFv) against human ICAM-1

Intercellular adhesion molecule-1 (ICAM-1) is an important factor in the progression of inflammatory responses in vivo. To develop a new anti-inflammatory drug to block the biological activity of ICAM-1, we produced a monoclonal antibody (Ka=4.19×10−8 M) against human ICAM-1. The anti-ICAM-1 single-chain variable antibody fragment (scFv) was expressed at a high level as inclusion bodies in Escherichia coli. We refolded the scFv (Ka=2.35×10−7 M) by ion-exchange chromatography, dialysis, and dilution. The results showed that column chromatography refolding by high-performance Q Sepharose had remarkable advantages over conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield of about 60 mg/L was higher with this method. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay, cell culture, and animal experiments were used to assess the immunological properties and biological activities of the renatured scFv.

Effect of candesartan on the expression of sclera-choroidal intercellular adhesion molecule-1 in hypercholesterolemic models

OBJECTIVE: To evaluate the effect of blocking the angiotensin II AT-1 receptor by the systemic administration of candesartan on the expression of intercellular adhesion molecule-1 in the sclera and choroid of hypercholesterolemic rabbits. METHODS: New Zealand rabbits were divided into 3 groups, as follows: GI, which was fed a rabbit standard diet; GII, which was fed a hypercholesterolemic diet; and GIII, which received hypercholesterolemic diet plus candesartan. Samples of the rabbits' sclera and choroid were then studied by hematoxylin-eosin staining and histomorphometric and immunohistochemical analyses for intercellular adhesion molecule-1 expression. RESULTS: Histological analysis of hematoxylin- and eosin-stained sclera and choroid revealed that macrophages were rarely present in GI, and GII had significantly increased macrophage numbers compared to GIII. Moreover, in GII, the sclera and choroid morphometry showed a significant increase in thickness in comparison to GI and GIII. GIII presented a significant increase in thickness in relation to GI. Sclera and choroid immunohistochemical analysis for intercellular adhesion molecule-1 expression revealed a significant increase in immunoreactivity in GII in relation to GI and GIII. GIII showed a significant increase in immunoreactivity in relation to GI. CONCLUSION: Candesartan reduced the expression of intercellular adhesion molecule-1 and consequently macrophage accumulation in the sclera and choroid of hypercholesterolemic rabbits. .

Pentoxifylline decreases serum level of adhesion molecules in atherosclerosis patients

Inflammation is involved in development, progression, and complications of atherosclerotic disease. Clinical studies have indicated that the level of monocyte chemoattractant protein 1 [MCP-1], IL-18, and adhesion molecules correlates with the severity of atherosclerosis and can predict future cardiovascular events. Experimental studies have shown pentoxifylline [PTX] reduces these factors in animal models. The purpose of the present pilot study was to evaluate effect of PTX on a group of inflammatory biomarkers in patients with coronary artery disease [CAD]. Forty patients with angiographically documented CAD, who fulfilled inclusion and exclusion criteria, were entered in the double-blind, randomized, pilot clinical study. The patients were randomly given PTX [400 mg three times daily] or placebo [3 tab/day] for 2 months. Serum concentrations of MCP-1, IL-18, intercellular adhesion Molecule 1 [ICAM-1], and vascular cell adhesion molecule 1 [VCAM-1] were measured before and at the end of intervention by enzyme-linked immunosorbant assay. Our study showed that the serum levels of ICAM-1 and VCAM-1 was decreased in the study population after two-month treatment [P<0.05]. Based on the results of our pilot study, administration of PTX in CAD patients significantly decreases adhesion molecules levels