title: Lymphangiogenesis in tissue-engineered small intestine.
abstract: BACKGROUND
  Lymphangiogenesis, the formation of lymphatic vessels, has not been reported in engineered tissue. The purpose of this study was to characterize lymphangiogenesis in tissue-engineered small intestine.
  
  
  METHODS
  Biodegradable polymer scaffolds seeded with intestinal organoid units were implanted into syngenic recipient rats. Twenty-three neointestinal grafts were harvested from adult rat recipients 1 to 8 weeks postimplantation. Cells expressing the lymphatic endothelial marker vascular endothelial growth factor receptor (VEGFR)-3 were detected immunohistochemically. The lymphangiogenic growth factor VEGF-C was quantified by enzyme-linked immunoadsorbent assay.
  
  
  RESULTS
  Between the first and eighth weeks, neointestinal cysts increased in volume and mass. Muscular and mucosal layers increased in thickness and developed to resemble normal intestine histologically. The proportion of neointestinal VEGFR-3-positive cells increased and ultimately, tubular structures developed that resembled lymphatics architecturally, were distinct from CD34-positive blood vessels, and lacked luminal erythrocytes.
  
  
  CONCLUSIONS
  Lymphangiogenesis occurs in tissue-engineered small intestine. This is the first demonstration of lymphatic vessels in an engineered tissue.
authors.affiliation: Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Duxbury
authors.forename: Tracy C
authors.initials: TC
authors.lastname: Grikscheit
authors.forename: James
authors.initials: J
authors.lastname: Gardner-Thorpe
authors.forename: Flavio G
authors.initials: FG
authors.lastname: Rocha
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ito
authors.forename: Alexander
authors.initials: A
authors.lastname: Perez
authors.forename: Stanley W
authors.initials: SW
authors.lastname: Ashley
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Vacanti
authors.forename: Edward E
authors.initials: EE
authors.lastname: Whang
mesh_terms: D000818:Animals; D007421:Intestine, Small / Q000033:anatomy & histology / Q000254:growth & development* / Q000378:metabolism / Q000637:transplantation*; D042583:Lymphangiogenesis; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors; D023822:Tissue Engineering; D014185:Transplantation, Isogeneic; D040321:Vascular Endothelial Growth Factor Receptor-3 / Q000378:metabolism
chemical_list: D040321:Vascular Endothelial Growth Factor Receptor-3