TY - JOUR
T1 - The latent transforming growth factor-β-binding protein-1 promotes in vitro differentiation of embryonic stem cells into endothelium
AU - Gualandris, A.
AU - Annes, J. P.
AU - Arese, M.
AU - Noguera, I.
AU - Jurukovski, V.
AU - Rifkin, D. B.
PY - 2000
Y1 - 2000
N2 - The latent transforming growth factor-β-binding protein-1 (LTBP-1) belongs to a family of extracellular glycoproteins that includes three additional isoforms (LTBP-2, -3, and -4) and the matrix proteins fibrillin-1 and -2. Originally described as a TGF-β-masking protein, LTBP-1 is involved both in the sequestration of latent TGF-β in the extracellular matrix and the regulation of its activation in the extracellular environment. Whereas the expression of LTBP-1 has been analyzed in normal and malignant cells and rodent and human tissues, little is known about LTBP-1 in embryonic development. To address this question, we used murine embryonic stem (ES) cells to analyze the appearance and role of LTBP-1 during ES cell differentiation. In vitro, ES cells aggregate to form embryoid bodies (EBs), which differentiate into multiple cell lineages. We analyzed LTBP-1 gene expression and LTBP-1 fiber appearance with respect to the emergence and distribution of cell types in differentiating EBs. LTBP-1 expression increased during the first 12 d in culture, appeared to remain constant between d 12 and 24, and declined thereafter. By immunostaining, fibrillar LTBP-1 was observed in those regions of the culture containing endothelial, smooth muscle, and epithelial cells. We found that inclusion of a polyclonal antibody to LTBP-1 during EB differentiation suppressed the expression of the endothelial specific genes ICAM-2 and von Willebrand factor and delayed the organization of differentiated endothelial cells into cord-like structures within the growing EBs. The same effect was observed when cultures were treated with either antibodies to TGF-β or the latency associated peptide, which neutralize TGF-β. Conversely, the organization of endothelial cells was enhanced by incubation with TGF-β1. These results suggest that during differentiation of ES cells LTBP-1 facilitates endothelial cell organization via a TGF-β-dependent mechanism.
AB - The latent transforming growth factor-β-binding protein-1 (LTBP-1) belongs to a family of extracellular glycoproteins that includes three additional isoforms (LTBP-2, -3, and -4) and the matrix proteins fibrillin-1 and -2. Originally described as a TGF-β-masking protein, LTBP-1 is involved both in the sequestration of latent TGF-β in the extracellular matrix and the regulation of its activation in the extracellular environment. Whereas the expression of LTBP-1 has been analyzed in normal and malignant cells and rodent and human tissues, little is known about LTBP-1 in embryonic development. To address this question, we used murine embryonic stem (ES) cells to analyze the appearance and role of LTBP-1 during ES cell differentiation. In vitro, ES cells aggregate to form embryoid bodies (EBs), which differentiate into multiple cell lineages. We analyzed LTBP-1 gene expression and LTBP-1 fiber appearance with respect to the emergence and distribution of cell types in differentiating EBs. LTBP-1 expression increased during the first 12 d in culture, appeared to remain constant between d 12 and 24, and declined thereafter. By immunostaining, fibrillar LTBP-1 was observed in those regions of the culture containing endothelial, smooth muscle, and epithelial cells. We found that inclusion of a polyclonal antibody to LTBP-1 during EB differentiation suppressed the expression of the endothelial specific genes ICAM-2 and von Willebrand factor and delayed the organization of differentiated endothelial cells into cord-like structures within the growing EBs. The same effect was observed when cultures were treated with either antibodies to TGF-β or the latency associated peptide, which neutralize TGF-β. Conversely, the organization of endothelial cells was enhanced by incubation with TGF-β1. These results suggest that during differentiation of ES cells LTBP-1 facilitates endothelial cell organization via a TGF-β-dependent mechanism.
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M3 - Article
C2 - 11102524
AN - SCOPUS:0033637929
VL - 11
SP - 4295
EP - 4308
JO - Molecular Biology of the Cell
JF - Molecular Biology of the Cell
SN - 1059-1524
IS - 12
ER -