title: Recombinant adeno-associated virus-based gene transfer of cathelicidin induces therapeutic neovascularization preferentially via potent collateral growth.
abstract: Therapeutic neovascularization is a concept well validated in animal models, however, without clear-cut success in clinical studies. To achieve prolonged transgene expression, recombinant adeno-associated virus (rAAV) was used in a chronic ischemic hind-limb model and the human antimicrobial peptide cathelicidin (LL-37/hCAP-18) was used as proangiogenic factor. Seven days after femoral artery excision, 0.5 x 10(11) rAAV particles encoding for green fluorescent protein (rAAV.GFP), cathelicidin (rAAV.cath), or vascular endothelial growth factor A (rAAV.VEGF-A) were retroinfused into the anterior tibial vein of rabbits (n = 5 per group). In addition, one rAAV.cath-treated group obtained a constant infusion with the phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin into the ischemic tissue starting on day 7. On day 7 and day 35 angiography of both hind limbs was performed for collateral quantification and frame count score (cinedensitometry). Capillary-to-muscle fiber ratios were obtained on day 35. Compared with controls, application of rAAV.cath induced a gain of perfusion (153 +/- 12 vs. 107 + 9% of day 7 controls) via increased collateral growth (length index, 161 +/- 14 vs. 97 +/- 9%, controls), but no significant capillary growth (1.16 +/- 0.09 vs. 0.99 +/- 0.08, controls). Wortmannin application completely abolished the effects of rAAV.cath, indicating the involvement of the PI3K signal pathway. In conclusion, rAAV-mediated cathelicidin expression is capable of inducing functionally relevant neovascularization, preferentially by collateral growth. The rAAV-based vectors as long-expressing vector expression systems and cathelicidin as proangiogenic factor provide a promising new combination in the treatment of peripheral artery disease.
authors.affiliation: Division of Pulmonology, Department of Internal Medicine, Hospital of the University of Marburg, Philipps Universität Marburg, Marburg, Germany.
authors.forename: Olaf
authors.initials: O
authors.lastname: Pinkenburg
authors.forename: Achim
authors.initials: A
authors.lastname: Pfosser
authors.forename: Rabea
authors.initials: R
authors.lastname: Hinkel
authors.forename: Martina
authors.initials: M
authors.lastname: Böttcher
authors.forename: Claudia
authors.initials: C
authors.lastname: Dinges
authors.forename: Corinna
authors.initials: C
authors.lastname: Lebherz
authors.forename: Shahana
authors.initials: S
authors.lastname: Sultana
authors.forename: Jörg
authors.initials: J
authors.lastname: Enssle
authors.forename: Chiraz
authors.initials: C
authors.lastname: El-Aouni
authors.forename: Hildegard
authors.initials: H
authors.lastname: Büning
authors.forename: Peter
authors.initials: P
authors.lastname: Boekstegers
authors.forename: Robert
authors.initials: R
authors.lastname: Bals
authors.forename: Christian
authors.initials: C
authors.lastname: Kupatt
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides; D054804:Cathelicidins / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D018014:Gene Transfer Techniques; D006614:Hindlimb / Q000098:blood supply; D006801:Humans; D007511:Ischemia / Q000628:therapy*; D018919:Neovascularization, Physiologic / Q000235:genetics*; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D023181:Antimicrobial Cationic Peptides; D054804:Cathelicidins; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A