title: Transmyocardial laser revascularization limits in vivo adenoviral-mediated gene transfer in porcine myocardium.
abstract: OBJECTIVE
  Transmyocardial laser revascularization (TMR) is emerging as a potential treatment option for patients with end-stage CAD, and adjuvant gene therapy may be helpful in further improving the results of the procedure. However, the effects of TMR on gene transfer are unknown.
  
  
  METHODS
  Swine underwent left thoracotomy. TMR was performed to create five channels at 2-cm intervals in the anterolateral free wall of the left ventricle (LV) followed by injection of 1 x 10(9) plaque-forming units (pfu) of a replication-deficient adenovirus vector carrying the reporter gene beta-galactosidase (Ad.Pac beta-gal). An additional five direct injections of 1 x 10(9) pfu Ad.Pac beta-gal were made at 2-cm intervals in the posterolateral LV of each heart. Control animals underwent TMR alone/vehicle alone (n = 3) or empty virus alone/no treatment (n = 3) of the anterolateral/posterolateral LV, respectively.
  
  
  RESULTS
  ELISA revealed significantly greater transgene expression in the direct Ad.Pac beta-gal injection versus TMR plus Ad.Pac beta-gal inject regions at both 3 (n = 6) (273.0 +/- 58.5 vs. 133.4 + 28.1 pg beta-gal/g protein, P = 0.02) and 7 days (n = 6) (180.0 + 59.9 vs. 56.7 + 18.1 pg beta-gal/g protein, P = 0.02) postoperatively. At 14 days postoperatively (n = 2), no transgene expression was detected in either region. No transgene expression was detected in any of the control regions at 3 days postoperatively. CD-18 staining revealed significantly greater inflammation in the TMR plus Ad.Pac beta-gal and TMR alone regions as compared to Ad.Pac beta-gal or vehicle (P < 0.001).
  
  
  CONCLUSIONS
  Adenoviral-mediated gene transfer in conjunction with TMR is possible, although TMR appears to limit the degree of transgene expression attained as compared to direct intramyocardial injection alone, likely due to the greater immune response observed with the former. These findings may have important implications for therapeutic strategies aimed at combining TMR with gene therapy for CAD.
authors.affiliation: Division of Cardiovascular and Thoracic Surgery, Duke University Medical Center, Durham, NC 27710, USA. chadh@acpub.duke.edu
authors.forename: G C
authors.initials: GC
authors.lastname: Hughes
authors.forename: B H
authors.initials: BH
authors.lastname: Annex
authors.forename: B
authors.initials: B
authors.lastname: Yin
authors.forename: A M
authors.initials: AM
authors.lastname: Pippen
authors.forename: P
authors.initials: P
authors.lastname: Lin
authors.forename: A P
authors.initials: AP
authors.lastname: Kypson
authors.forename: K G
authors.initials: KG
authors.lastname: Peters
authors.forename: J E
authors.initials: JE
authors.lastname: Lowe
authors.forename: K P
authors.initials: KP
authors.lastname: Landolfo
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D003131:Combined Modality Therapy; D003327:Coronary Disease / Q000601:surgery / Q000628:therapy*; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D053685:Laser Therapy; D009204:Myocardial Revascularization; D013552:Swine; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D001616:beta-Galactosidase