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Phenotypic and Functional Characterization of Endothelial Colony Forming Cells Derived from Human Umbilical Cord Blood
Published on: April 13, 2012
ALCAM (CD166): its role in hematopoietic and endothelial development
1Center for Tsukuba Advanced Research Alliance and Institute of Basic Medical Sciences, University of Tsukuba, Japan. oohneda@tara.tsukuba.ac.jp
Blood
|September 25, 2001
Summary
Activated Leukocyte Cell Adhesion Molecule (ALCAM) is crucial for embryonic hematopoiesis and blood vessel formation. This molecule is specifically expressed in embryonic endothelial cells, supporting hematopoietic progenitor development.
Area of Science:
- Developmental Biology
- Hematology
- Cell Biology
Background:
- Embryonic hematopoiesis relies on yolk sac and dorsal aorta endothelium.
- A novel molecule linked to embryonic hematopoiesis was sought using a yolk sac stromal cell line (YSCL-72).
Purpose of the Study:
- To identify and characterize novel molecules involved in embryonic hematopoiesis.
- To investigate the role of Activated Leukocyte Cell Adhesion Molecule (ALCAM, CD166) in embryonic development.
Main Methods:
- Comparative analysis of YSCL-72 and adult aorta endothelial cell line (EOMA).
- Immunohistochemical studies to determine ALCAM expression patterns.
- Functional assays using ALCAM-transfected EOMA cells to assess hematopoietic progenitor support.
- Evaluation of ALCAM's role in capillary tube formation and hemangioblast differentiation.
Main Results:
- ALCAM (CD166) was specifically expressed in YSCL-72, not EOMA.
- Immunohistochemistry confirmed ALCAM expression in embryonic yolk sac and dorsal aorta endothelium, absent in adult aorta.
- ALCAM-transfected EOMA cells enhanced hematopoietic progenitor cell development.
- ALCAM involvement in capillary tube formation and hemangioblast differentiation was observed.
Conclusions:
- ALCAM is a key molecule in embryonic hematopoiesis.
- ALCAM plays a significant role in vasculoangiogenesis and hemangioblast differentiation.
- ALCAM expression is restricted to embryonic vasculature, highlighting its developmental importance.
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