title: Cellular phenotypes and spatio-temporal patterns of lymphatic vessel development in embryonic mouse hearts.
abstract: BACKGROUND
  The origin of cardiac lymphatics from venous endothelial cells or from scattered lymphangioblasts has been discussed in the literature. We aimed to establish the stage when lymphatic vessels appear in the developing mouse heart, the location of the first lymphatics, and to define cellular phenotypes of growing lymphatics.
  
  
  RESULTS
  We found that scattered Lyve-1-positive cells located in the subepicardial area of developing heart expressed CD45, CD68, F4/80, or CD11b but not CD31. Prox-1(+)/Lyve-1(+) cellular cords or vessels were found to invade 12.5-13.5-dpc hearts via two routes: from the venous pole, i.e., dorsal atrioventricular sulcus, or on the dorsal atrial surface from mediastinum and from the arterial pole, i.e., along the great arteries. The Prox-1(+)/Lyve-1(+) vessels were located among the Prox-1(+)/Lyve-1(-) cords and among the scattered Prox-1(-)/Lyve-1(+) cells. The Prox-1(+)/Lyve-1(-) cellular cords/tubules dominate initially at the arterial pole whereas Lyve-1(+)/Prox-1(-) cellular cords/tubules dominate initially on the venous pole, i.e., dorsal atrioventricular sulcus. The Lyve-1(+)/CD45(+), Lyve-1(+)/CD11b(+), Lyve-1(+)/F4/80(+) and Lyve-1(+)/CD68(+) cells were subsequently found to be co-opted to the wall of the developing lymphatic vessels while gaining Flk-1.
  
  
  CONCLUSIONS
  Lymphatic primordia exhibit different cellular phenotypes and different spatiotemporal pattern on the venous pole as compared with the arterial pole of the heart.
authors: Department of Pathomorphology, Medical University of Warsaw, Warsaw, Poland.
authors: A
authors: A
authors: Flaht
authors: E
authors: E
authors: Jankowska-Steifer
authors: D M
authors: DM
authors: Radomska
authors: M
authors: M
authors: Madej
authors: G
authors: G
authors: Gula
authors: M
authors: M
authors: Kujawa
authors: A
authors: A
authors: Ratajska
mesh_terms: D000818:Animals; D019521:Body Patterning / Q000235:genetics / Q000502:physiology; D004622:Embryo, Mammalian; D018507:Gene Expression Regulation, Developmental; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D006321:Heart / Q000196:embryology*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D042583:Lymphangiogenesis / Q000235:genetics / Q000502:physiology; D042601:Lymphatic Vessels / Q000166:cytology* / Q000196:embryology*; D026901:Membrane Transport Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008954:Models, Biological; D009206:Myocardium / Q000166:cytology / Q000276:immunology; D038081:Organogenesis / Q000235:genetics / Q000502:physiology; D010641:Phenotype; D013997:Time Factors; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism; D000098551:Prospero-Related Homeobox 1 Protein
chemical_list: D006023:Glycoproteins; D018398:Homeodomain Proteins; D026901:Membrane Transport Proteins; D025521:Tumor Suppressor Proteins; D000098551:Prospero-Related Homeobox 1 Protein; C492273:LYVE1 protein, mouse