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Beta 1 integrin is essential for teratoma growth and angiogenesis.

Bloch W, Forsberg E, Lentini S, Brakebusch C, Martin K, Krell HW, Weidle UH, Addicks K, Fässler R - J. Cell Biol. (1997)

Bottom Line: Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface.The formation of a complex vasculature, however, was significantly delayed and of poor quality in beta1- embryoid bodies.Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in beta 1- embryoid bodies.

View Article: PubMed Central - PubMed

Affiliation: Institute for Anatomy, University of Cologne, 50931 Cologne, Germany.

ABSTRACT
Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of beta 1 integrin during teratoma formation, we compared teratomas induced by normal and beta1- ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, beta 1- ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of beta 1- teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in beta1- teratomas. Basement membranes were present but with irregular shape and detached from the cell surface. Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell-derived endothelial cells. In contrast, beta 1- teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although beta 1- deficient endothelial cells were absent in teratomas, beta 1- ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in beta1- embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in beta 1- embryoid bodies.

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Immunostaining of a normal (+/+) and a β1- (−/−) teratoma for the expression of vWF and for β1 integrin expression.  Teratomas were removed 21 d after inoculation and sectioned. Neighboring sections were stained for vWF and β1 integrin expression,  respectively. Whereas normal teratomas have large vessels, β1- teratomas have small vessels. Note that like in normal tumors vessels  of β1- tumors coexpress vWF and β1 integrin indicating that endothelial cells are host derived. Bar, 100 μm.
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Figure 7: Immunostaining of a normal (+/+) and a β1- (−/−) teratoma for the expression of vWF and for β1 integrin expression. Teratomas were removed 21 d after inoculation and sectioned. Neighboring sections were stained for vWF and β1 integrin expression, respectively. Whereas normal teratomas have large vessels, β1- teratomas have small vessels. Note that like in normal tumors vessels of β1- tumors coexpress vWF and β1 integrin indicating that endothelial cells are host derived. Bar, 100 μm.

Mentions: Hematoxylin/Eosin staining, as well as immunostaining for the endothelial markers vWF and PECAM revealed a large number of circular vessels of various sizes in β1 +/+ teratomas (Fig. 7 A). In contrast, in β1- tumors, vessels were smaller in size and of irregular shape (Fig. 7 B).


Beta 1 integrin is essential for teratoma growth and angiogenesis.

Bloch W, Forsberg E, Lentini S, Brakebusch C, Martin K, Krell HW, Weidle UH, Addicks K, Fässler R - J. Cell Biol. (1997)

Immunostaining of a normal (+/+) and a β1- (−/−) teratoma for the expression of vWF and for β1 integrin expression.  Teratomas were removed 21 d after inoculation and sectioned. Neighboring sections were stained for vWF and β1 integrin expression,  respectively. Whereas normal teratomas have large vessels, β1- teratomas have small vessels. Note that like in normal tumors vessels  of β1- tumors coexpress vWF and β1 integrin indicating that endothelial cells are host derived. Bar, 100 μm.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2139829&req=5

Figure 7: Immunostaining of a normal (+/+) and a β1- (−/−) teratoma for the expression of vWF and for β1 integrin expression. Teratomas were removed 21 d after inoculation and sectioned. Neighboring sections were stained for vWF and β1 integrin expression, respectively. Whereas normal teratomas have large vessels, β1- teratomas have small vessels. Note that like in normal tumors vessels of β1- tumors coexpress vWF and β1 integrin indicating that endothelial cells are host derived. Bar, 100 μm.
Mentions: Hematoxylin/Eosin staining, as well as immunostaining for the endothelial markers vWF and PECAM revealed a large number of circular vessels of various sizes in β1 +/+ teratomas (Fig. 7 A). In contrast, in β1- tumors, vessels were smaller in size and of irregular shape (Fig. 7 B).

Bottom Line: Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface.The formation of a complex vasculature, however, was significantly delayed and of poor quality in beta1- embryoid bodies.Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in beta 1- embryoid bodies.

View Article: PubMed Central - PubMed

Affiliation: Institute for Anatomy, University of Cologne, 50931 Cologne, Germany.

ABSTRACT
Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of beta 1 integrin during teratoma formation, we compared teratomas induced by normal and beta1- ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, beta 1- ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of beta 1- teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in beta1- teratomas. Basement membranes were present but with irregular shape and detached from the cell surface. Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell-derived endothelial cells. In contrast, beta 1- teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although beta 1- deficient endothelial cells were absent in teratomas, beta 1- ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in beta1- embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in beta 1- embryoid bodies.

Show MeSH
Related in: MedlinePlus