title: The longevity of a bilayered skin substitute after application to venous ulcers.
abstract: BACKGROUND
  A bilayered skin substitute composed of allogeneic keratinocytes and fibroblasts in a collagen gel has been approved by the US Food and Drug Administration for the treatment of venous and diabetic ulcers. Its mechanism of action has not been fully determined.
  
  
  OBJECTIVE
  To determine the longevity of allogeneic fibroblasts and keratinocytes in a bilayered skin substitute in patients with venous leg ulcers.
  
  
  METHODS
  Ten patients with venous leg ulcers were treated with a bilayered skin substitute on day 0, days 3 to 5, and weeks 1 through 3. Biopsy specimens of the grafted wound were taken. We used polymerase chain reaction analysis to determine whether allogeneic DNA was present in the biopsy specimens.
  
  
  RESULTS
  We detected allogeneic DNA in 2 of 8 specimens at 1 month after initial grafting. Neither of the 2 patients showed persistence of allogeneic DNA at 2 months after initial grafting.
  
  
  CONCLUSIONS
  Allogeneic cells from a bilayered skin substitute do not appear to survive permanently after grafting for treatment of venous leg ulcers. Other mechanisms of action might include cytokine release, structural support, or provision of a moist wound environment.
authors.affiliation: Department of Dermatology, Boston University School of Medicine, 609 Albany St, Boston, MA 02118, USA.
authors.forename: Tania J
authors.initials: TJ
authors.lastname: Phillips
authors.forename: Jasmin
authors.initials: J
authors.lastname: Manzoor
authors.forename: Adriana
authors.initials: A
authors.lastname: Rojas
authors.forename: Cary
authors.initials: C
authors.lastname: Isaacs
authors.forename: Polly
authors.initials: P
authors.lastname: Carson
authors.forename: Michael
authors.initials: M
authors.lastname: Sabolinski
authors.forename: Jan
authors.initials: J
authors.lastname: Young
authors.forename: Vincent
authors.initials: V
authors.lastname: Falanga
mesh_terms: D003094:Collagen / Q000235:genetics / Q000494:pharmacology* / Q000627:therapeutic use*; D005347:Fibroblasts / Q000187:drug effects* / Q000473:pathology / Q000637:transplantation*; D005500:Follow-Up Studies; D006085:Graft Survival; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000473:pathology / Q000637:transplantation*; D016133:Polymerase Chain Reaction; D017768:Skin, Artificial; D013997:Time Factors; D016896:Treatment Outcome; D014647:Varicose Ulcer / Q000235:genetics* / Q000473:pathology / Q000628:therapy*
chemical_list: C117898:Apligraf; D003094:Collagen