Abstract P119: Human Podoplanin+/vegfr-3+/lyve-1+ Monocytes are Lymphatic Endothelial Precursors
Lymphatic vessels are involved in the development of various inflammatory disorders, and lymphatic vessel regeneration has been increasingly investigated to develop therapies for lymphatic diseases. Here we report that Podoplanin+/VEGFR-3+/LYVE-1+ is a valid marker for human lymphatic endothelial precursors and the triple-positive cells can be used in lymphatic regeneration. During 5-day culture on an ultra-low attachment surface dish, human peripheral blood mononuclear cells (PBMCs) underwent exponential growth, aggregating into a sphere-like structure and expressing several lymphatic endothelial cell (LEC) markers and lymphangiogenic transcription factors. When dissociated from the aggregate and cultured on a gelatin-coated dish, the cells were attached to the surface. The attached cells were triple positive for LEC markers e.g. Podoplanin, LYVE-1, VEGFR-3. Furthermore, seeded in Matrigel with LECs, the 5-day aggregate-derived cells were incorporated into lymphatic endothelial network. The 5-day aggregates were largely positive for CD14+, a monocyte marker. The CD14+ population was sorted into Podoplanin-positive and negative group for further characterization. Notably, CD14+/Podoplanin+ cells showed increased expression of lymphangiogenic molecules (e.g. VEGFR-3, LYVE-1) both at the genetic and protein levels. Also, CD14+/Podoplanin+ cells secreted higher levels of lymphangiogenic cytokines (VEGF, HGF, PDGF-BB). ELISA results showed that CD14+/Podoplanin+ cells produced more lymphangiogenic cytokines than CD14+/Podoplanin- cells. Local injection of monocyte aggregates significantly increased lymphatic neovascularization and facilitated healing of the skin wound model of nude mice, with CD14+/Podoplanin+ group showing the most dramatic result. Our data suggests that Podoplanin-positive monocytes can be transdifferentiated into lymphatic endothelial precursor cells, and cells with triple positivity for Podoplanin, VEGFR-3, and LYVE-1 can be a promising cell source for therapy against human lymphatic vessel diseases.
Author Disclosures: J. Choi: None. J. Hur: None. J. Jang: None. I. Oh: None. H. Lee: None. P. Nham: None. I. Hwang: None. T. Kim: None. J. Kang: None. C. Yoon: None. H. Yang: None. Y. Kwon: None. H. Cho: None. Y. Park: None. H. Kim: None.
- © 2015 by American Heart Association, Inc.