title: Potential of mesenchymal stem cell in stabilization of abdominal aortic aneurysm sac.
abstract: BACKGROUND
  In their origin, abdominal aortic aneurysms (AAAs) are related to an inflammatory reaction within the aortic wall, which can lead to weakness and degeneration of this structure. One of the most widely accepted treatment modalities for AAAs is the placement of stent grafts. Nevertheless, in some patients blood re-enters the aneurysm sac, creating so-called leaks, which constitute a renewed risk of rupture and death.This study explores the possibility of filling aneurysm sacs treated by endovascular aneurysm repair with adipose tissue-derived mesenchymal stem cells (ASCs) in a porcine model.
  
  
  METHODS
  We developed a porcine model using 22 animals by creating an artificial AAA made with a Dacron patch. AAAs were then treated with a coated stent that isolated the aneurysm sac, after which we introduced allogeneic ASC into the sac. Animals were followed-up for up to 3 mo. The experiment consisted of the aforementioned surgical procedure performed first, followed by computed tomography and echo-Doppler imaging during the follow-up, and finally, after sacrificing the animals, histologic analysis of tissue samples from the site of cell implantation by a blinded observer and the detection of implanted cells by immunofluorescence detection of the Y chromosome.
  
  
  RESULTS
  Our findings demonstrate the survival of ASCs over the 3 mo after implantation and histologic changes associated with this treatment. Treated animals had less acute and chronic inflammation throughout the study period, and we observed increasing fibrosis of the aneurysm sac, no accumulation of calcium, and a regeneration of elastic fibers in the artery.
  
  
  CONCLUSIONS
  The combination of endovascular aneurysm repair and cell therapy on AAAs has promising results for the stabilization of the sac, resulting in the generation of living tissue that can secure the stent graft and even showing some signs of wall regeneration. The therapeutic value of such cell-based therapy will require further investigation.
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Universitario La Paz-Instituto de Investigación del Hospital Universitario La Paz, Madrid, Spain; Department of Surgery, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Riera del Moral
authors.affiliation: Department of Experimental Surgery, Hospital Universitario La Paz-Instituto de Investigación del Hospital Universitario La Paz, Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Largo
authors.affiliation: Department of Pathology, Hospital Universitario Rey Juan Carlos, Móstoles, Madrid, Spain.
authors.forename: J R
authors.initials: JR
authors.lastname: Ramirez
authors.affiliation: Cell Therapy Laboratory, Research Department, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Vega Clemente
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Universitario La Paz-Instituto de Investigación del Hospital Universitario La Paz, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Fernández Heredero
authors.affiliation: Department of Angiology and Vascular Surgery, Hospital Universitario La Paz-Instituto de Investigación del Hospital Universitario La Paz, Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Riera de Cubas
authors.affiliation: Department of Surgery, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain; Cell Therapy Laboratory, Research Department, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain; Department of Surgery, University Hospital Fundación Jiménez Díaz, Madrid, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Garcia-Olmo
authors.affiliation: Department of Surgery, Faculty of Medicine, Universidad Autónoma de Madrid, Madrid, Spain; Cell Therapy Laboratory, Research Department, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain. Electronic address: mariano.garcia@fjd.es.
authors.forename: M
authors.initials: M
authors.lastname: Garcia-Arranz
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D001012:Aorta, Abdominal / Q000473:pathology; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000601:surgery*; D002454:Cell Differentiation; D005260:Female; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D013552:Swine; D014656:Vascular Surgical Procedures
keywords: Abdominal aortic aneurysm; Aortic injury; Cell implantation; Cell therapy; Mesenchymal stem cell; Porcine model