1. ¹Cardion AG, Erkrath, Germany
2. ²Boehringer Ingelheim Pharma GmbH & Co. KG, Germany
3. ³Herzzentrum Coswig/Anhalt, Coswig, Germany

Correspondence: Dr MC Lenter, Department of Cadiovascular Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, Biberach D-88397, Germany

⁴Current address: Kourion Therapeutics AG, Langenfeld, Germany

⁵Both authors share senior authorship

Received 13 February 2004; Accepted 5 July 2004; Published online 7 October 2004.

Abstract

Local infusion of recombinant monocyte chemoattractant protein-1 (MCP-1) has been shown to enhance collateral artery formation in rabbit and pig hindlimb models. Owing to clinical disadvantages of protein infusion, a nonviral, liposome-based MCP-1 gene transfer was developed. Collateralization in a porcine hindlimb model served to provide a proof-of-principle for the functional benefit of MCP-1 overexpression. Development of arterial conductance as a measure of functionally relevant collateralization was evaluated in occluded as well as untreated hindlimbs in each animal. At the time of occlusion, MCP-1 and control DNA/DC-30 lipoplexes were transferred to femoral arteries of Goettingen minipigs (two therapeutic MCP-1 groups: 2 and 4 g and one control group), using the Infiltrator^® local drug-delivery device. At 2 weeks following occlusion, collateralization was determined as changes in peripheral haemodynamic conductance, peripheral over aortic blood pressure ratio and angiographically visible morphology of the peripheral vessel tree. Nonviral MCP-1 gene transfer significantly improved peripheral conductance (control 11.692.78%, 2 g 23.812.81%, P<0.05 and 4 g 23.363.1%, P<0.05; n=12 per group) as well as the ratio of peripheral over aortic blood pressure (control 0.640.03%, 2 g 0.750.02%, P<0.05 and 4 g 0.750.02%, P<0.05; n=12 per group) when compared to the untreated controls 2 weeks after occlusion. Thus, it could be demonstrated for the first time that in situ overexpression of MCP-1 following local nonviral gene transfer is a potential approach to improve peripheral collateralization.