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Circulation Research. 1998;83:233-240

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(Circulation Research. 1998;83:233-240.)
© 1998 American Heart Association, Inc.


Original Contribution

Tie2 Receptor Ligands, Angiopoietin-1 and Angiopoietin-2, Modulate VEGF-Induced Postnatal Neovascularization

Takayuki Asahara, Donghui Chen, Tomono Takahashi, Koshi Fujikawa, Marianne Kearney, Meredith Magner, George D. Yancopoulos, , Jeffrey M. Isner

From the Departments of Medicine (Cardiology) and Biomedical Research, St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, Mass; and Regeneron Pharmaceuticals, Inc (G.D.Y.), Tarrytown, NY.

Correspondence to Jeffrey M. Isner, MD, St. Elizabeth's Medical Center, 736 Cambridge St, Boston, MA 02135.


*    Abstract
up arrowTop
*Abstract
down arrowIntroduction
down arrowMaterials and Methods
down arrowResults
down arrowDiscussion
down arrowReferences
 
Abstract—Angiopoietin-1 (Ang1) has been recently identified as the major physiological ligand for the tyrosine kinase receptor Tie2 and assigned responsibility for recruiting and sustaining periendothelial support cells. Angiopoietin-2 (Ang2) was found to disrupt blood vessel formation in the developing embryo by antagonizing the effects of Ang1 and Tie2 and was thus considered to represent a natural Ang1/Tie2 inhibitor. In vivo effects of either angiopoietin on postnatal neovascularization, however, have not been previously described. Accordingly, we used the cornea micropocket assay of neovascularization to investigate the impact of angiopoietins on neovascularization in vivo. Neither Ang1 nor Ang2 alone promoted neovascularization. Pellets containing vascular endothelial growth factor (VEGF) alone induced corneal neovascularity extending from the limbus across the cornea. Addition of Ang1 to VEGF (Ang1+VEGF) produced an increase in macroscopically evident perfusion of the corneal neovasculature without affecting macroscopic measurements of length (0.58±0.03 mm) or circumferential neovascularity (136±10°). In contrast, pellets containing Ang2+VEGF promoted significantly longer (0.67±0.05 mm) and more circumferential (160±15°) neovascularity than VEGF alone or Ang1+VEGF (P<0.05). Excess soluble Tie2 receptor (sTie2-Fc) precluded modulation of VEGF-induced neovascularization by both Ang2 and Ang1. Fluorescent microscopic findings demonstrated enhanced capillary density (fluorescence intensity, 2.55±0.23 e+9 versus 1.23±0.17 e+9, P<0.01) and increased luminal diameter of the basal limbus artery (39.0±2.8 versus 27.9±1.3 µm, P<0.01) for Ang1+VEGF compared with VEGF alone. In contrast to Ang1+VEGF, Ang2+VEGF produced longer vessels and, at the tip of the developing capillaries, frequent isolated sprouting cells. In the case of Ang2+VEGF, however, luminal diameter of the basal limbus artery was not increased (26.7±1.9 versus 27.9±1.3, P=NS). These findings constitute what is to our knowledge the first direct demonstration of postnatal bioactivity associated with either angiopoietin. In particular, these results indicate that angiopoietins may potentiate the effects of other angiogenic cytokines. Moreover, these findings provide in vivo evidence that Ang1 promotes vascular network maturation, whereas Ang2 works to initiate neovascularization.


Key Words: angiopoietin • Tie2 receptor • vascular endothelial growth factor • angiogenesis • endothelial cell


*    Introduction
up arrowTop
up arrowAbstract
*Introduction
down arrowMaterials and Methods
down arrowResults
down arrowDiscussion
down arrowReferences
 
Establishment and remodeling of blood vessels is regulated by paracrine signals from the transmembrane TKRs of endothelial cells. Flk-1 and Flt-1 are 2 such TKRs, which, together with their cognate ligand VEGF, have been shown to be required for blood vessel development during embryogenesis1 2 ; this receptor/ligand family also has been shown to augment postnatal neovascularization.3 4 5 6 7

The Tie receptors, Tie1 and Tie2, constitute a second family of endothelial cell–specific TKRs, and the latter has been shown recently to be widely expressed in the quiescent vasculature of adult tissues.8 Tie2-/- mice die during embryogenesis at day 9.5 to 10.5; necropsy analyses have shown that the endothelial cells of such mice are present in normal numbers and assembled into tubes, but the vessels are immature and lack branch networks and hierarchical organization into large and small vessels.9 10 Deletion of Tie1 results in embryonic lethality at day 14.5; the finding of edema and hemorrhage in these mice has been interpreted as evidence that Tie1 signaling modulates the hemodynamics of transcapillary fluid exchange.10 11

Observations in human subjects have revealed that deficient SM cell investment typical of venous malformations is associated with a mutation in the Tie2 TKR,12 suggesting that the Tie2 system may regulate the endothelial cell recruitment of stromal cells required to encase and thereby stabilize primitive endothelial tubes.

Recently, the ligands of the Tie2 receptor have been identified as Ang1 and Ang2. Ang1 was identified as the major physiological ligand for Tie2, responsible for recruiting and sustaining periendothelial support cells. Ang2 was found to disrupt blood vessel formation in the developing embryo by antagonizing the effects of Ang1 and Tie2, and it was thus concluded that Ang2 represents a natural Ang1/Tie2 inhibitor. Extrapolation of these developmental findings to postnatal neovascularization has led to the dual inferences that Ang1 may induce maturation and stabilization of developing neovasculature,13 whereas Ang2 may cause destabilization required for additional sprout formation.14 In vivo effects of either angiopoietin on postnatal neovascularization, however, have not been previously described.

Accordingly, in the present series of experiments, we used the mouse corneal micropocket assay to determine the function of these novel endothelial cell–specific cytokines on postnatal neovascularization in vivo.


*    Materials and Methods
up arrowTop
up arrowAbstract
up arrowIntroduction
*Materials and Methods
down arrowResults
down arrowDiscussion
down arrowReferences
 
Reagents
Human Ang1, Ang2, and sTie2-Fc were kindly supplied by Regeneron Pharmaceuticals, Inc. The recombinant protein was formulated in buffer solution consisting of 0.05 mol/L Tris-HCl, pH 7.5, 150 mmol/L NaCl, and 0.05% Chaps. Ang1 is a genetically engineered variant of naturally occurring Ang1 that retains similar properties in all assays. Soluble Tie2-Fc is a recombinant fusion protein consisting of the ectodomain of the Tie2 receptor fused to the Fc portion of human IgG1. Previous studies have shown that sTie2-Fc binds to Ang1, Ang2, and mouse angiopoietins.14 Recombinant human VEGF165 was a generous gift of Dr Bruce Keyt (Genentech Inc, South San Francisco, Calif).

Mouse Cornea Neovascularization Assay
Age-matched (8 weeks) C57BL/6J male mice (Jackson Labs, Bar Harbor, Me) were used for all experiments. Preoperative anesthesia was limited to intraperitoneal pentobarbital injection (160 mg/kg). Corneal pockets were created in the eyes of each mouse using a modified von Graefe cataract knife.15

A 0.34x0.34-mm sucrose aluminum sulfate (Bukh Meditec) pellet coated with hydron polymer type NCC (IFN Science) containing 1 of the agents indicated below was implanted into the corneal pocket. Pellets were positioned 1.0 mm from the corneal limbus, and erythromycin ophthalmic ointment (E. Foufera) was applied to each operated eye. The corneas of all mice were routinely examined by slit-lamp biomicroscopy on postoperative days 4 or 6 after pellet implantation. Vessel length and the arc of corneal circumference occupied by neovascularity (circumferential neovascularity, in degrees) were measured on the sixth postoperative day when all corneas were photographed. After these measurements were completed, mice received an intravenous injection of 500 µg of the endothelial cell–specific marker BS-1 lectin conjugated to FITC (Vector Laboratory). Thirty minutes later, the animals were killed. The eyes were enucleated and fixed in 1% paraformaldehyde solution. After fixation, the corneas were placed on glass slides and examined by fluorescence microscopy. Several mice in each group did not receive BS-1 lectin injection; instead, the eyes were excised and fixed in 100% methanol solution for immunohistochemical staining.

Study Design
Age-matched (8 weeks) C57BL/6J male mice (Jackson Labs, Bar Harbor, Me) were divided into 9 groups. Each mouse underwent surgical implantation of pellets containing 1 of the following: control buffer (0.05 mol/L Tris-HCl, pH 7.5, 150 mmol/L NaCl, 0.05% Chaps) alone; Ang1 alone (300 ng/pellet); Ang2 alone (300ng/pellet); control buffer with VEGF (control+VEGF, 300 ng/pellet); Ang1 with VEGF (Ang1+VEGF, 300 ng/pellet); Ang2 with VEGF (Ang2+VEGF, 300 ng/pellet); sTie2-Fc with control buffer and VEGF (sTie2+control+VEGF, 300 ng/pellet); sTie2-Fc with Ang1 and VEGF (sTie2+Ang1+VEGF, 300 ng/pellet); and sTie2-Fc with Ang2 and VEGF (sTie2+Ang2+VEGF, 300 ng/pellet).

Quantification of Corneal Neovasculature
Integrated optical density (IOD) from the cornea-derived fluorescent slides was measured using a Cooke SVGA cooled CCD camera attached to a Nikon Diaphot inverted microscope. The digital images were processed using Media Cybernetics Image Pro Plus 3.0 software. Initially, all fluorescent images from different groups were acquired directly from the microscope to the computer screen using the same 2-second exposure time. The contour of the vascular area was traced, and the IOD was automatically calculated. The IOD equals the sum of all pixels, each of which has a value from 1 to 4096 gray levels, divided by the whole area. Results were expressed as mean±SEM. The differences between each individual group were evaluated by ANOVA. Differences were considered significant at P<0.05.

Immunohistochemistry
For immunohistochemical staining, the excised eyes were fixed immediately in 100% methanol overnight. After enucleation, the excised corneal hemispheres prepared under the dissecting microscope were embedded in paraffin. Sections of 5 µm thickness, cut either in cross section or longitudinally, were used for immunohistochemistry. Immunohistochemical staining for endothelial cells was carried out using a rat monoclonal antibody against mouse CD-31 (Pharmingen). For detection of periendothelial cells, a mouse monoclonal antibody against SM {alpha}-actin conjugated with alkaline phosphatase (Sigma) was used. A polyclonal peroxidase–labeled anti-rat immunoglobulin (Signet Laboratories) was used as secondary antibody for CD31. Vascular lumens bordered by CD31-positive cells were counted on cross sections of neovascularized cornea. To evaluate the frequency of periendothelial cell recruitment in corneal neovascularization, SM {alpha}-actin–positive cells were manually counted on tissue sections cut in cross section as well. The number of positive lumens in each case was expressed as mean±SEM. Group differences were analyzed by ANOVA. Differences were considered statistically significant at P<0.05.


*    Results
up arrowTop
up arrowAbstract
up arrowIntroduction
up arrowMaterials and Methods
*Results
down arrowDiscussion
down arrowReferences
 
On the sixth postoperative day after pellet implantation, corneal neovascularization was evaluated qualitatively (Figure 1Down) and quantitatively using slit-lamp biomicroscopy to measure vessel length and circumferential neovascularity (Figure 2Down). Neither the control buffer pellet nor pellets containing Ang1 or Ang2 alone induced neovascularization. Pellets containing VEGF alone induced corneal neovascularity extending from the limbus across the cornea (Figure 1Down); these vessels constituted 120±9° of the corneal circumference and measured 0.52±0.03 mm in length. The addition of Ang1 to VEGF (Ang1+VEGF) produced an increase in macroscopically evident perfusion of the corneal neovasculature (Figure 3Down) without affecting macroscopic measurements of length (0.58±0.03 mm) or circumferential neovascularity (136±10°). In contrast, pellets containing Ang2+VEGF promoted significantly longer (0.67±0.05 mm) and more circumferential (160±15°) neovascularity than VEGF alone or Ang1+VEGF (P<0.05). An excess of sTie2-Fc precluded modulation of VEGF-induced neovascularization by either angiopoietin (Ang2 as well as Ang1). Neovascularization induced by control buffer+VEGF was not attenuated by sTie2-Fc, excluding a potential contribution from endogenous angiopoietins.



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Figure 1. Macroscopic photographs of mouse cornea obtained by slit-lamp biomicroscopy 6 days after pellet implantation. Macroscopic evidence of corneal neovascularization was not observed with control buffer pellet or with pellets containing Ang1 or Ang2 alone. Pellets containing VEGF alone induced corneal neovascularity extending from the limbus across the cornea. The combination of Ang1 and VEGF showed enriched vascularity, although length (distance from limbus toward pellet) of the new vessels was similar to that seen with VEGF alone. Ang2+VEGF resulted in vessels with increased length (as well as circumferential extent of neovascularity; see Figure 2Up) compared with VEGF alone or Ang1+VEGF. Addition of sTie2-Fc did not change vascularity induced by VEGF but reduced both vascularity seen with Ang1+VEGF and increased vessel length seen with Ang2+VEGF.



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Figure 2. Vessel length (millimeters) and circumferential extent (degrees) of neovascularization measured macroscopically by slit-lamp biomicroscopy 6 days after surgery. Neovascularization induced by Ang2+VEGF is characterized by a statistically significant increase in both vessel length and circumferential extent of neovascularity compared with control (Cont) pellet or Ang1+VEGF. Introduction of sTie2-Fc obviates both findings (*P<0.05).



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Figure 3. In situ BS-1 lectin fluorescent staining of corneal limbus vessels 6 days after pellet insertion. Limbus vessels were unchanged in response to pellets containing control buffer, Ang1 alone, and Ang2 alone. Pellet containing VEGF alone resulted in corneal neovascularization. Further enhancement of vascularity and limbus arterial diameter (arrowhead) was observed with the combination of Ang1+VEGF; note that the length of the new vascular sprouts, however, is similar to those seen with VEGF alone. In contrast, the length of the vascular sprouts was observed to be increased in response to Ang2+VEGF; moreover, frequent isolated endothelial cells (arrows) were observed at the growing edge of the capillary tips. The fluorescent photomicrographs confirm macroscopic observations regarding addition of sTie2-Fc: no change in VEGF alone but substantial attenuation of vascularity in the case of Ang1+VEGF and vessel length as well as vascularity in the case of Ang2+VEGF.

Fluorescence microscopic findings resulting from premortem immunostaining with BS-1 lectin permitted more detailed histopathologic analysis. Compared with control+VEGF, Ang1+VEGF enhanced capillary density and luminal diameter of the basal limbus artery (Figure 3Up); this corresponded to a significant increase in fluorescence intensity (2.55±0.23 e+9 versus 1.23±0.17 e+9, P<0.01; Figure 4Down) and luminal diameter of the basal limbus artery (39.0±2.8 versus 27.9±1.3 µm, P<0.01; Figure 5Down). In contrast to Ang1+VEGF, Ang2+VEGF produced longer vessels and, at the tip of the developing capillaries, frequent isolated sprouting cells (Figure 3Up). These findings were not observed with Ang1+VEGF. In the case of Ang2+VEGF, however, luminal diameter of the basal limbus artery was not increased (26.7±1.9 versus 27.9±1.3, P=NS; Figure 5Down). The differential effects observed for Ang1 versus Ang2 in combination with VEGF were apparent at day 4 (Figure 6Down).



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Figure 4. Quantitative analysis of neovasculature induced by control buffer (Cont)+VEGF, Ang1+VEGF, or Ang2+VEGF. Measurement of integrated optical density from fluorescent photomicrograph of cornea with digital image analysis was used to determine fluorescence density. Both Ang1+VEGF and Ang2+VEGF revealed significant increase in fluorescence density in comparison to VEGF alone (*P<0.01).



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Figure 5. Luminal diameter of cornea limbus arteries treated with control buffer (Cont) +VEGF, Ang1+VEGF, or Ang2+VEGF. The luminal diameter of basal limbus artery in response to Ang1+VEGF was significantly increased in comparison with VEGF alone or Ang2+VEGF (*P<0.05).



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Figure 6. Corneal neovascularization induced by VEGF with control buffer, Ang1, or Ang2 and evaluated by in situ BS-1 lectin fluorescence staining 4 days after pellet insertion. A, Appearance of nascent vascular sprouts induced by VEGF. B, More complex vascularity induced by combination of Ang1+VEGF. C, Ang2+VEGF also results in more robust vasculature, including increased length of sprouts and plethora of isolated endothelial cells at the growing tips of the sprouts. D, Higher-power photomicrograph of Ang1+VEGF showing lumen development at 4 days. E, Higher power view of Ang2+VEGF showing isolated endothelial cells (arrows) at sprout tips.

When sTie2-Fc was included with VEGF and control buffer in the implanted pellets, histopathologic vascular morphometry was unchanged. In contrast, sTie2-Fc obviated modulation of corneal neovascularization resulting from addition of Ang1 and Ang2 to the implanted pellets. These findings suggest an agonist function for both Ang1 and Ang2 in modulating VEGF-induced corneal neovascularization.

Light microscopic sections stained with hematoxylin and eosin disclosed only rare inflammatory cells associated with corneal neovascularization. A similar extent of low-level inflammation was observed after implantation of the control buffer pellet as well as pellets containing Ang1 or Ang2 alone, none of which induced neovascularization. This suggests that an inflammatory response is not a prerequisite for neovascularization in this cornea model, as suggested by others.16

To investigate specific histoarchitectural differences in neovascularization resulting from Ang1 versus Ang2 in combination with VEGF, we analyzed light microscopic sections prepared for immunohistochemical staining with antibodies to CD31 and SM {alpha}-actin. Immunostaining for CD31 disclosed an increased number of vascular lumens per cross section in tissue sections retrieved from animals receiving Ang1+VEGF versus control buffer+VEGF (155.8±32.1 versus 33.0±3.9 per cross section, P<0.05). Sections retrieved from the Ang2+VEGF group also disclosed an increased number of vascular lumens compared with the control+VEGF group (80.6±16.2 versus 33.0±3.9 per cross section), but this failed to achieve statistical significance (P=NS).

While both Ang1 and Ang2 resulted in an increased number of vascular lumens, the neovasculature developing in response to each of these 2 cytokines differed in 2 respects. First, the lumens of vessels constituting the neovasculature of Ang1+VEGF group were typically larger than those of the control+VEGF group; those vessels that developed in response to Ang2+VEGF, however, were of lesser luminal diameter than those in the Ang1+VEGF group and in this respect similar to those of the control+VEGF group (Figure 7Down). While this feature was difficult to quantify because of the diminutive size of the lumens in general, it is illustrated qualitatively in the representative histological sections shown in Figure 7Down. Second, the neovasculature of these 2 groups was characterized by a marked difference in periendothelial cell frequency (Figure 8Down). Recruitment of periendothelial cells was more frequent in Ang1+VEGF (50.0±14.2 per cross section) than in Ang2+VEGF (11.6±1.4) or control+VEGF (5.4±1.4) groups.



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Figure 7. Immunohistochemical staining of neovasculature induced by VEGF, Ang1+VEGF, and Ang+VEGF. A through C, Representative photomicrographs of tissue sections stained with antibody to CD31. The number of vascular lumens in Ang1+VEGF was significantly (P<0.05) higher than that observed with control buffer+VEGF. Ang2 increased the number of vascular lumens compared with control buffer+VEGF but failed to achieve statistical significance (P=NS). Note that Ang1, but not Ang2, also resulted in increased size of vascular lumens. D through F, Sections stained with antibody to SM {alpha}-actin show that Ang1, but not Ang2, also increased recruitment of periendothelial cells.



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Figure 8. A, Quantification of vascular lumens per cross section. B, Quantification of SM {alpha}-actin–positive cells per cross section (*P<0.05 versus control+VEGF by ANOVA).


*    Discussion
up arrowTop
up arrowAbstract
up arrowIntroduction
up arrowMaterials and Methods
up arrowResults
*Discussion
down arrowReferences
 
We used the cornea micropocket assay of neovascularization to investigate the impact of angiopoietins on neovascularization in vivo. This cytokine-containing sucralfate assay is unique by virtue of the fact that it yields a predictable, persistent, and aggressive neovascular response that is dependent on direct stimulation of blood vessel development rather than indirect neovascularization induced by inflammation.16 We observed only very few inflammatory cells in association with corneal neovascularization. The fact that a similarly limited number of inflammatory cells was observed after implantation of the control buffer pellet as well as pellets containing Ang1 or Ang2 alone—none of which induced neovascularization—suggests that an active inflammatory response is not a prerequisite for neovascularization in this cornea model, as suggested by others.16 Neovascularity related to pellet implantation was thus exclusively cytokine dependent.

Previous reports have suggested that angiopoietins alone were not mitogenic for endothelial cells in culture nor did they induce tube formation within a collagen substrate.14 In the present experiments, neither Ang1 nor Ang2 alone promoted neovascularization. In contrast, however, when coadministered with VEGF, Ang1 had an important modulatory effect on corneal neovascularization. The increase in vascular density seen with Ang1+VEGF is consistent with previous studies showing that combined administration of endothelial mitogens may have a synergistic effect on neovascularization.17 18 19 The increase in luminal diameter of vessels constituting the neovasculature as well as the limbus artery may represent an additional modulatory effect, although the possibility that this was due to vasodilation resulting from augmented flow into the enriched plexus of corneal vessels cannot be excluded. The development of a more complex vascular network characterized by vessels of increased luminal size and more frequent recruitment of periendothelial cells may be considered evidence for a maturation effect of Ang1 on VEGF-induced neovascularization. This idea was suggested by Suri et al,13 who characterized the vascular network of Ang1-/- mice as less complex and comprising fewer large arteries, most of which were of lesser caliber and more poorly invested by periendothelial cells than the vasculature of wild-type mice.

The modulatory impact of Ang2 on VEGF-induced neovascularization was morphologically distinct and thereby quite different from simple enhancement of vascular density induced by VEGF. The circumferential extent and the length of vessels cooperatively induced by Ang2+VEGF were significantly increased compared with control+VEGF or Ang1+VEGF. Moreover, histological examination disclosed isolated migrating endothelial cells at the leading tip of capillaries coursing toward the pellet. Neither the size of the limbus artery nor that of vessels constituting the neovasculature, however, were enhanced in the case of Ang2+VEGF. We interpret these findings to indicate that the effect of Ang2 on VEGF-induced neovascularization is to promote vascular destabilization and sprouting required to initiate neovascularization. Consistent with this interpretation, Maisonpierre et al14 previously suggested that Ang2 may collaborate with VEGF at the leading edge of invading vascular sprouts by blocking constitutive stabilization or the maturation function of Ang1, thus allowing vessels to revert to and remain in a more plastic state in which they may be more responsive to sprouting signals provided by VEGF.

The effect of Ang1 or Ang2 on VEGF-induced neovascularization constitutes inferential evidence for Tie2 expression in the cornea micropocket assay. Coadministration of sTie2-Fc had no inhibitory effect on angiogenesis induced by VEGF alone, indicating that endogenous angiopoietins do not contribute to corneal neovascularization. Moreover, we found very few {alpha}-SM actin–positive periendothelial cells in VEGF-induced neovasculature, whereas abundant periendothelial cells were seen in the cornea of Ang1+VEGF group. This suggests that periendothelial cell recruitment in neovascular development is dependent on Ang1 and that VEGF-induced corneal neovascularization, in the absence of endogenous angiopoietin, does not include Ang1-dependent periendothelial cell recruitment for vascular maturation, at least up to day 6.

Second, coadministration of sTie2-Fc abolished the modulating effects of Ang1 and Ang2 on VEGF-induced neovascularization. This finding is consistent with the recent demonstration by Lin et al20 that a soluble form of the extracellular domain of murine Tie2 blocked tumor angiogenesis, including tumor vascular length density, and consequently tumor growth. Moreover, the fact that sTie2-Fc preempted the modulating influence of not only Ang1 but Ang2 as well suggests an agonist effect for Ang2 on neovascularization. Maisonpierre et al14 were unable to show evidence of Tie2 activation by Ang2 (no tyrosine phosphorylation) in human endothelial cells; in contrast, Ang2 was shown to activate the Tie2 receptor when it was ectopically expressed in nonendothelial (NIH 3T3) cells. The present findings thus constitute the initial demonstration that Ang2 may activate the Tie2 receptor in vascular cells and support the notion that Ang2 may facilitate neovascularization.21

Because Tie2 expression is restricted to endothelial lineage22 23 and certain phenotypes of immature hematopoietic cells,24 it is possible that the cells responding to Ang2 in the present experiment could be either activated endothelial cells or endothelial progenitor cells25 derived from circulating blood that have homed to the site of corneal neovascularization. We have found previously that endothelial progenitor cells express the Tie2 receptor25 and, more recently, shown that endothelial progenitor cells make a substantive contribution to VEGF-induced corneal neovascularity (T. Asahara, D. Chen, J.M. Isner, unpublished data, 1997). Endothelial progenitor cells, in contrast to fully differentiated endothelial cells, may constitute a state that allows signaling from the Tie2 receptor to occur after binding by Ang2.

In summary, these findings constitute what is to our knowledge the first direct demonstration of angiopoietin bioactivity in postnatal animals. In particular, these results indicate that angiopoietins, as suggested by Wong et al,8 may potentiate the effects of other angiogenic cytokines. Moreover, these findings provide in vivo evidence that Ang1 promotes vascular network maturation, whereas Ang2 works to initiate neovascularization, concepts that were inferred from targeted genetic experiments13 14 or detection of gene expression in postnatal organs.14 Further studies will be required to elucidate the regulatory mechanisms by which angiopoietins modulate cells of endothelial lineage through the Tie2 receptor.


*    Selected Abbreviations and Acronyms
 
Ang1 = angiopoietin-1
Ang2 = angiopoietin-2
BS-1 = Bandeiraea simplicifolia lectin-1
SM = smooth muscle
sTie2-Fc = soluble Tie2 receptor
TKR = tyrosine kinase receptor
VEGF = vascular endothelial growth factor

Received December 29, 1997; accepted April 22, 1998.


*    References
up arrowTop
up arrowAbstract
up arrowIntroduction
up arrowMaterials and Methods
up arrowResults
up arrowDiscussion
*References
 
1. Shalaby F, Rossant J, Yamaguchi TP, Gertsenstein M, Wu X-F, Breitman ML, Schuh AC. Failure of blood-island formation and vasculogenesis in Flk-1 deficient mice. Nature. 1995;376:62–66.[Medline] [Order article via Infotrieve]

2. Fong G-H, Rossant J, Gerstenstein M, Breitman ML. Role of the Flt-1 receptor tyrosine kinase in regulating the assembly of vascular endothelium. Nature. 1995;376:66–70.[Medline] [Order article via Infotrieve]

3. Takeshita S, Zheng LP, Brogi E, Kearney M, Pu LQ, Bunting S, Ferrara N, Symes JF, Isner JM. Therapeutic angiogenesis: a single intra-arterial bolus of vascular endothelial growth factor augments revascularization in a rabbit ischemic hindlimb model. J Clin Invest. 1994;93:662–670.

4. Isner JM, Pieczek A, Schainfeld R, Blair R, Haley L, Asahara T, Rosenfield K, Razvi S, Walsh K, Symes J. Clinical evidence of angiogenesis following arterial gene transfer of phVEGF165. Lancet. 1996;348:370–374.[Medline] [Order article via Infotrieve]

5. Banai S, Jaklitsch MT, Shou M, Lazarous DF, Scheinowitz M, Biro S, Epstein SE, Unger EF. Angiogenic-induced enhancement of collateral blood flow to ischemic myocardium by vascular endothelial growth factor in dogs. Circulation. 1994;89:2183–2189.[Abstract/Free Full Text]

6. Pearlman JD, Hibberd MG, Chuang ML, Harada K, Lopez JJ, Gladston SR, Friedman M, Sellke FW, Simons M. Magnetic resonance mapping demonstrates benefits of VEGF-induced myocardial angiogenesis. Nat Med. 1995;1:1085–1089.[Medline] [Order article via Infotrieve]

7. Li J, Brown LF, Hibberd MG, Grossman JD, Morgan JP, Simons M. VEGF, flk-1, and flt-1 expression in a rat myocardial infarction model of angiogenesis. Am J Physiol. 1996;270:H1803–H1811.[Abstract/Free Full Text]

8. Wong AL, Haroon ZA, Werner S, Dewhirst MW, Greenberg CS, Peters KG. Tie2 expression and phosphorylation in angiogenic and quiescent adult tissues. Circ Res. 1997;81:567–574.[Abstract/Free Full Text]

9. Dumont DJ, Gradwohl G, Guo-Hua F, Puri MC, Gertsenstein M, Auerbach A, Breitman ML. Dominant-negative and targeted null mutations in the endothelial receptor tyrosine kinase, tek, reveal a critical role in vasculogenesis of the embryo. Genes Dev. 1994;8:1897–1909.[Abstract/Free Full Text]

10. Sato TN, Tozawa Y, Deutsch U, Wolburg-Buchholz K, Fujiwara Y, Gentron-Maguire M, Gridley T, Wolburg H, Risau W, Qin Y. Distinct roles of the receptor tyrosine kinases Tie-1 and Tie-2 in blood vessel formation. Nature. 1995;376:70–74.[Medline] [Order article via Infotrieve]

11. Puri MC, Rossant J, Alitalo K, Bernstein A, Partanen J. The receptor tyrosine kinase TIE is required for integrity and survival of vascular endothelial cells. EMBO J. 1995;14:5884–5891.[Medline] [Order article via Infotrieve]

12. Vikkula M, Boon LM, Carraway KL III, Calvert JT, Diamonti AJ, Goumnerov B, Pasyk KA, Marchuk DA, Warman ML, Cantley LC, Mulliken JB, Olsen BR. Vascular dysmorphogenesis caused by an activating mutation in the receptor tyrosine kinase TIE2. Cell. 1996;87:1181–1190.[Medline] [Order article via Infotrieve]

13. Suri C, Jones PF, Patan S, Bartunkova S, Maisonpierre PC, Davis S, Sato T, Yancopoulos GD. Requisite role of angiopoietin-1, a ligand for the TIE2 receptor, during embryonic angiogenesis. Cell. 1996;87:1171–1180.[Medline] [Order article via Infotrieve]

14. Maisonpierre P, Suri C, Jones P, Bartunkova S, Wiegand S, Radziejewski C, Compton D, McClain J, Aldrich T, Papadopoulos N, Daly T, Davis S, Sato T, Yancopoulos G. Angiopoietin-2, a natural antagonist for Tie2 that disrupts in vivo angiogenesis. Science. 1997;277:55–60.[Abstract/Free Full Text]

15. Muthukkaruppan V, Auerbach R. Angiogenesis in the mouse cornea. Science. 1979;28:1416–1418.

16. Kenyon BM, Voest EE, Chen CC, Flynn E, Folkman J, D'Amato RJ. A model of angiogenesis in the mouse cornea. Invest Ophthalmol Vis Sci. 1996;37:1625–1632.[Abstract/Free Full Text]

17. Goto F, Goto K, Weindel K, Folkman J. Synergistic effects of vascular endothelial growth factor and basic fibroblast growth factor on the proliferation and cord formation of bovine capillary endothelial cells within collagen gels. Lab Invest. 1993;69:508–517.[Medline] [Order article via Infotrieve]

18. Pepper MS, Ferrara N, Orci L, Montesano R. Potent synergism between vascular endothelial growth factor and basic fibroblast growth factor in the induction of angiogenesis in vitro. Biochem Biophys Res Commun. 1992;189:824–831.[Medline] [Order article via Infotrieve]

19. Asahara T, Bauters C, Zheng LP, Takeshita S, Bunting S, Ferrara N, Symes JF, Isner JM. Synergistic effect of vascular endothelial growth factor and basic fibroblast growth factor on angiogenesis in vivo. Circulation. 1995;92(suppl II):II-365–II-371.

20. Lin P, Polverini P, Dewhirst M, Shan S, Rao PS, Peters K. Inhibition of tumor angiogenesis using a soluble receptor establishes a role for Tie2 in pathologic vascular growth. J Clin Invest. 1997;100:2072–2078.[Medline] [Order article via Infotrieve]

21. Hanahan D. Signaling vascular morphogenesis and maintenance. Science. 1997;277:48–50.[Free Full Text]

22. Dumont DJ, Yamaguchi TP, Conlon RA, Rossant J, Breitman ML. tec, a novel tyrosine kinase gene located on mouse chromosome-4, is expressed in endothelial cells and their presumptive precursors. Oncogene. 1992;7:1471–1480.[Medline] [Order article via Infotrieve]

23. Schnurch H, Risau W. Expression of tie-2, a member of a novel family of receptor tyrosine kinases, in the endothelial cell lineage. Development. 1993;119:957–968.[Abstract/Free Full Text]

24. Iwama A, Hamaguchi I, Hashiyama M, Murayama Y, Yasunaga K, Suda T. Molecular cloning and characterization of mouse TIE and TEK receptor tyrosine kinase genes and their expression in hematopoietic stem cells. Biochem Biophys Res Commun. 1993;195:301–309.[Medline] [Order article via Infotrieve]

25. Asahara T, Murohara T, Sullivan A, Silver M, van der Zee R, Li T, Witzenbichler B, Schatteman G, Isner JM. Isolation of putative progenitor endothelial cells for angiogenesis. Science. 1997;275:965–967.




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Home page
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[Abstract] [Full Text] [PDF]


Home page
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[Abstract] [Full Text] [PDF]


Home page
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[Abstract] [Full Text] [PDF]


Home page
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Biological characterization of angiopoietin-3 and angiopoietin-4
FASEB J, August 1, 2004; 18(11): 1200 - 1208.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
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Am J Physiol Heart Circ Physiol, July 1, 2004; 287(1): H187 - H195.
[Abstract] [Full Text] [PDF]


Home page
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M.H. Tayebjee, G.Y.H. Lip, and R.J. MacFadyen
Collateralization and the response to obstruction of epicardial coronary arteries
QJM, May 1, 2004; 97(5): 259 - 272.
[Abstract] [Full Text] [PDF]


Home page
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F. Fan, O. Stoeltzing, W. Liu, M. F. McCarty, Y. D. Jung, N. Reinmuth, and L. M. Ellis
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[Abstract] [Full Text] [PDF]


Home page
Am. J. Pathol.Home page
D. Watanabe, H. Takagi, K. Suzuma, I. Suzuma, H. Oh, H. Ohashi, S. Kemmochi, A. Uemura, T. Ojima, E. Suganami, et al.
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[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
P. Pichiule, J. C. Chavez, and J. C. LaManna
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J. Biol. Chem., March 26, 2004; 279(13): 12171 - 12180.
[Abstract] [Full Text] [PDF]


Home page
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Home page
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D. Chu, C. C. Sullivan, L. Du, A. J. Cho, M. Kido, P. L. Wolf, M. D. Weitzman, S. W. Jamieson, and P. A. Thistlethwaite
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Ann. Thorac. Surg., February 1, 2004; 77(2): 449 - 456.
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Home page
J. Am. Soc. Nephrol.Home page
B. Rizkalla, J. M. Forbes, M. E. Cooper, and Z. Cao
Increased Renal Vascular Endothelial Growth Factor and Angiopoietins by Angiotensin II Infusion Is Mediated by Both AT1 and AT2 Receptors
J. Am. Soc. Nephrol., December 1, 2003; 14(12): 3061 - 3071.
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G. Matsumura, S. Miyagawa-Tomita, T. Shin'oka, Y. Ikada, and H. Kurosawa
First Evidence That Bone Marrow Cells Contribute to the Construction of Tissue-Engineered Vascular Autografts In Vivo
Circulation, October 7, 2003; 108(14): 1729 - 1734.
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Home page
Circ. Res.Home page
M. Yamakawa, L. X. Liu, T. Date, A. J. Belanger, K. A. Vincent, G. Y. Akita, T. Kuriyama, S. H. Cheng, R. J. Gregory, and C. Jiang
Hypoxia-Inducible Factor-1 Mediates Activation of Cultured Vascular Endothelial Cells by Inducing Multiple Angiogenic Factors
Circ. Res., October 3, 2003; 93(7): 664 - 673.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Pathol.Home page
S. Sarlos, B. Rizkalla, C. J. Moravski, Z. Cao, M. E. Cooper, and J. L. Wilkinson-Berka
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Am. J. Pathol., September 1, 2003; 163(3): 879 - 887.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
O. Stoeltzing, S. A. Ahmad, W. Liu, M. F. McCarty, J. S. Wey, A. A. Parikh, F. Fan, N. Reinmuth, M. Kawaguchi, C. D. Bucana, et al.
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Cancer Res., June 15, 2003; 63(12): 3370 - 3377.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
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Expression of VEGF and angiopoietins-1 and -2 during ischemia-induced coronary angiogenesis
Am J Physiol Heart Circ Physiol, June 5, 2003; 285(1): H352 - H358.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Pathol.Home page
S. Babaei, K. Teichert-Kuliszewska, Q. Zhang, N. Jones, D. J. Dumont, and D. J. Stewart
Angiogenic Actions of Angiopoietin-1 Require Endothelium-Derived Nitric Oxide
Am. J. Pathol., June 1, 2003; 162(6): 1927 - 1936.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
P. G. Lloyd, B. M. Prior, H. T. Yang, and R. L. Terjung
Angiogenic growth factor expression in rat skeletal muscle in response to exercise training
Am J Physiol Heart Circ Physiol, May 1, 2003; 284(5): H1668 - H1678.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
R. R. White, S. Shan, C. P. Rusconi, G. Shetty, M. W. Dewhirst, C. D. Kontos, and B. A. Sullenger
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PNAS, April 29, 2003; 100(9): 5028 - 5033.
[Abstract] [Full Text] [PDF]


Home page
Mol. Cell. Biol.Home page
N. Jones, S. H. Chen, C. Sturk, Z. Master, J. Tran, R. S. Kerbel, and D. J. Dumont
A Unique Autophosphorylation Site on Tie2/Tek Mediates Dok-R Phosphotyrosine Binding Domain Binding and Function
Mol. Cell. Biol., April 15, 2003; 23(8): 2658 - 2668.
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Home page
Eur Heart JHome page
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S. S. Gerety and D. J. Anderson
Cardiovascular ephrinB2 function is essential for embryonic angiogenesis
Development, March 5, 2003; 129(6): 1397 - 1410.
[Abstract] [Full Text] [PDF]


Home page
BloodHome page
Y. Yamada, Y. Oike, H. Ogawa, Y. Ito, H. Fujisawa, T. Suda, and N. Takakura
Neuropilin-1 on hematopoietic cells as a source of vascular development
Blood, March 1, 2003; 101(5): 1801 - 1809.
[Abstract] [Full Text] [PDF]


Home page
IOVSHome page
H. Takagi, S. Koyama, H. Seike, H. Oh, A. Otani, M. Matsumura, and Y. Honda
Potential Role of the Angiopoietin/Tie2 System in Ischemia-Induced Retinal Neovascularization
Invest. Ophthalmol. Vis. Sci., January 1, 2003; 44(1): 393 - 402.
[Abstract] [Full Text] [PDF]


Home page
Mol Cancer ResHome page
N. Cheng, D. M. Brantley, H. Liu, Q. Lin, M. Enriquez, N. Gale, G. Yancopoulos, D. P. Cerretti, T. O. Daniel, and J. Chen
Blockade of EphA Receptor Tyrosine Kinase Activation Inhibits Vascular Endothelial Cell Growth Factor-Induced Angiogenesis
Mol. Cancer Res., November 1, 2002; 1(1): 2 - 11.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Pathol.Home page
W.-H. Zhu, A. MacIntyre, and R. F. Nicosia
Regulation of Angiogenesis by Vascular Endothelial Growth Factor and Angiopoietin-1 in the Rat Aorta Model : Distinct Temporal Patterns of Intracellular Signaling Correlate with Induction of Angiogenic Sprouting
Am. J. Pathol., September 1, 2002; 161(3): 823 - 830.
[Abstract] [Full Text] [PDF]


Home page
Clin. Cancer Res.Home page
E. S. J. M. de Bont, V. Fidler, T. Meeuwsen, F. Scherpen, K. Hahlen, and W. A. Kamps
Vascular Endothelial Growth Factor Secretion Is an Independent Prognostic Factor for Relapse-free Survival in Pediatric Acute Myeloid Leukemia Patients
Clin. Cancer Res., September 1, 2002; 8(9): 2856 - 2861.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
I. B. Lobov, P. C. Brooks, and R. A. Lang
From the Cover: Angiopoietin-2 displays VEGF-dependent modulation of capillary structure and endothelial cell survival in vivo
PNAS, August 20, 2002; 99(17): 11205 - 11210.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
S. R. Wedge, D. J. Ogilvie, M. Dukes, J. Kendrew, R. Chester, J. A. Jackson, S. J. Boffey, P. J. Valentine, J. O. Curwen, H. L. Musgrove, et al.
ZD6474 Inhibits Vascular Endothelial Growth Factor Signaling, Angiogenesis, and Tumor Growth following Oral Administration
Cancer Res., August 15, 2002; 62(16): 4645 - 4655.
[Abstract] [Full Text] [PDF]


Home page
J. Histochem. Cytochem.Home page
E. Tham, J. Wang, F. Piehl, and G. Weber
Upregulation of VEGF-A Without Angiogenesis in a Mouse Model of Dilated Cardiomyopathy Caused by Mitochondrial Dysfunction
J. Histochem. Cytochem., July 1, 2002; 50(7): 935 - 944.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Pathol.Home page
S.-C. Shih, G. S. Robinson, C. A. Perruzzi, A. Calvo, K. Desai, J. E. Green, I. U. Ali, L. E. H. Smith, and D. R. Senger
Molecular Profiling of Angiogenesis Markers
Am. J. Pathol., July 1, 2002; 161(1): 35 - 41.
[Abstract] [Full Text] [PDF]


Home page
J. Biol. Chem.Home page
G. Camenisch, M. T. Pisabarro, D. Sherman, J. Kowalski, M. Nagel, P. Hass, M.-H. Xie, A. Gurney, S. Bodary, X. H. Liang, et al.
ANGPTL3 Stimulates Endothelial Cell Adhesion and Migration via Integrin alpha vbeta 3 and Induces Blood Vessel Formation in Vivo
J. Biol. Chem., May 3, 2002; 277(19): 17281 - 17290.
[Abstract] [Full Text] [PDF]


Home page
Clin. Cancer Res.Home page
K. Rodins, M. Cheale, N. Coleman, and S. B. Fox
Minichromosome Maintenance Protein 2 Expression in Normal Kidney and Renal Cell Carcinomas: Relationship to Tumor Dormancy and Potential Clinical Utility
Clin. Cancer Res., April 1, 2002; 8(4): 1075 - 1081.
[Abstract] [Full Text] [PDF]


Home page
Cold Spring Harb Symp Quant BiolHome page
S.M. DALLABRIDA and M.A. RUPNICK
Vascular Endothelium in Tissue Remodeling: Implications for Heart Failure
Cold Spring Harb Symp Quant Biol, January 1, 2002; 67(0): 417 - 428.
[Abstract] [PDF]


Home page
Cold Spring Harb Symp Quant BiolHome page
K.S. MOULTON
Plaque Angiogenesis: Its Functions and Regulation
Cold Spring Harb Symp Quant Biol, January 1, 2002; 67(0): 471 - 482.
[Abstract] [PDF]


Home page
Cancer Res.Home page
K. J. Sales, A. A. Katz, B. Howard, R. P. Soeters, R. P. Millar, and H. N. Jabbour
Cyclooxygenase-1 Is Up-Regulated in Cervical Carcinomas: Autocrine/Paracrine Regulation of Cyclooxygenase-2, Prostaglandin E Receptors, and Angiogenic Factors by Cyclooxygenase-1
Cancer Res., January 1, 2002; 62(2): 424 - 432.
[Abstract] [Full Text] [PDF]


Home page
ANN INTERN MEDHome page
S. B. Freedman and J. M. Isner
Therapeutic Angiogenesis for Coronary Artery Disease
Ann Intern Med, January 1, 2002; 136(1): 54 - 71.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
E. S. J. M. de Bont, J. E. J. Guikema, F. Scherpen, T. Meeuwsen, W. A. Kamps, E. Vellenga, and N. A. Bos
Mobilized Human CD34+ Hematopoietic Stem Cells Enhance Tumor Growth in a Nonobese Diabetic/Severe Combined Immunodeficient Mouse Model of Human Non-Hodgkin's Lymphoma
Cancer Res., October 1, 2001; 61(20): 7654 - 7659.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
K. Koga, T. Todaka, M. Morioka, J.-i. Hamada, Y. Kai, S. Yano, A. Okamura, N. Takakura, T. Suda, and Y. Ushio
Expression of Angiopoietin-2 in Human Glioma Cells and Its Role for Angiogenesis
Cancer Res., August 1, 2001; 61(16): 6248 - 6254.
[Abstract] [Full Text] [PDF]


Home page
Clin. Cancer Res.Home page
A. L. Harris, P. Reusch, B. Barleon, C. Hang, N. Dobbs, and D. Marme
Soluble Tie2 and Flt1 Extracellular Domains in Serum of Patients with Renal Cancer and Response to Antiangiogenic Therapy
Clin. Cancer Res., July 1, 2001; 7(7): 1992 - 1997.
[Abstract] [Full Text] [PDF]


Home page
Circ. Res.Home page
M. Yokoyama and T. Hirase
Harmonic Interplay of Angiogenic Growth Factors in the Development of Coronary Blood Vessels
Circ. Res., June 8, 2001; 88(11): 1099 - 1101.
[Full Text] [PDF]


Home page
Eur Heart JHome page
R Tabibiazar and S.G Rockson
Angiogenesis and the ischaemic heart
Eur. Heart J., June 1, 2001; 22(11): 903 - 918.
[PDF]


Home page
IOVSHome page
M. Hangai, T. Murata, N. Miyawaki, C. Spee, J. I. Lim, S. He, D. R. Hinton, and S. J. Ryan
Angiopoietin-1 Upregulation by Vascular Endothelial Growth Factor in Human Retinal Pigment Epithelial Cells
Invest. Ophthalmol. Vis. Sci., June 1, 2001; 42(7): 1617 - 1625.
[Abstract] [Full Text]


Home page
DiabetesHome page
A. Otani, H. Takagi, H. Oh, S. Koyama, and Y. Honda
Angiotensin II Induces Expression of the Tie2 Receptor Ligand, Angiopoietin-2, in Bovine Retinal Endothelial Cells
Diabetes, April 1, 2001; 50(4): 867 - 875.
[Abstract] [Full Text]


Home page
Clin. Cancer Res.Home page
M. J. Currie, S. P. Gunningham, C. Han, P. A. E. Scott, B. A. Robinson, A. L. Harris, and S. B. Fox
Angiopoietin-1 Is Inversely Related to Thymidine Phosphorylase Expression in Human Breast Cancer, Indicating a Role in Vascular Remodeling
Clin. Cancer Res., April 1, 2001; 7(4): 918 - 927.
[Abstract] [Full Text]


Home page
Cardiovasc ResHome page
K. Teichert-Kuliszewska, P. C. Maisonpierre, N. Jones, A. I.M. Campbell, Z. Master, M. P. Bendeck, K. Alitalo, D. J. Dumont, G. D. Yancopoulos, and D. J. Stewart
Biological action of angiopoietin-2 in a fibrin matrix model of angiogenesis is associated with activation of Tie2
Cardiovasc Res, February 16, 2001; 49(3): 659 - 670.
[Abstract] [Full Text] [PDF]


Home page
Cancer Res.Home page
S. A. Ahmad, W. Liu, Y. D. Jung, F. Fan, M. Wilson, N. Reinmuth, R. M. Shaheen, C. D. Bucana, and L. M. Ellis
The Effects of Angiopoietin-1 and -2 on Tumor Growth and Angiogenesis in Human Colon Cancer
Cancer Res., February 1, 2001; 61(4): 1255 - 1259.
[Abstract] [Full Text]


Home page
Circ. Res.Home page
S. Fujiyama, H. Matsubara, Y. Nozawa, K. Maruyama, Y. Mori, Y. Tsutsumi, H. Masaki, Y. Uchiyama, Y. Koyama, A. Nose, et al.
Angiotensin AT1 and AT2 Receptors Differentially Regulate Angiopoietin-2 and Vascular Endothelial Growth Factor Expression and Angiogenesis by Modulating Heparin Binding-Epidermal Growth Factor (EGF)-Mediated EGF Receptor Transactivation
Circ. Res., January 19, 2001; 88(1): 22 - 29.
[Abstract] [Full Text] [PDF]


Home page
Arterioscler. Thromb. Vasc. Bio.Home page
J. K. Chae, I. Kim, S. T. Lim, M. J. Chung, W. H. Kim, H. G. Kim, J. K. Ko, and G. Y. Koh
Coadministration of Angiopoietin-1 and Vascular Endothelial Growth Factor Enhances Collateral Vascularization
Arterioscler Thromb Vasc Biol, December 1, 2000; 20(12): 2573 - 2578.
[Abstract] [Full Text] [PDF]


Home page
J. Clin. Endocrinol. Metab.Home page
C. Wulff, H. Wilson, P. Largue, W. C. Duncan, D. G. Armstrong, and H. M. Fraser
Angiogenesis in the Human Corpus Luteum: Localization and Changes in Angiopoietins, Tie-2, and Vascular Endothelial Growth Factor Messenger Ribonucleic Acid
J. Clin. Endocrinol. Metab., November 1, 2000; 85(11): 4302 - 4309.
[Abstract] [Full Text]


Home page
Circ. Res.Home page
C. Willam, P. Koehne, J. S. Jurgensen, M. Grafe, K. D. Wagner, S. Bachmann, U. Frei, and K.-U. Eckardt
Tie2 Receptor Expression Is Stimulated by Hypoxia and Proinflammatory Cytokines in Human Endothelial Cells
Circ. Res., September 1, 2000; 87(5): 370 - 377.
[Abstract] [Full Text] [PDF]


Home page
Ann Rheum DisHome page
T. Uchida, M. Nakashima, Y. Hirota, Y. Miyazaki, T. Tsukazaki, and H. Shindo
Immunohistochemical localisation of protein tyrosine kinase receptors Tie-1 and Tie-2 in synovial tissue of rheumatoid arthritis: correlation with angiogenesis and synovial proliferation
Ann Rheum Dis, August 1, 2000; 59(8): 607 - 614.
[Abstract] [Full Text]


Home page
Cardiovasc ResHome page
M. Bongrazio, C. Baumann, A. Zakrzewicz, A. R Pries, and P. Gaehtgens
Evidence for modulation of genes involved in vascular adaptation by prolonged exposure of endothelial cells to shear stress
Cardiovasc Res, August 1, 2000; 47(2): 384 - 393.
[Abstract] [Full Text] [PDF]


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