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Angiogenic potential of endothelial progenitor cells and embryonic stem cells.

Rae PC, Kelly RD, Egginton S, St John JC - (2011)

Bottom Line: We also described the production of highly angiogenic EPC-comparable cells from pluripotent embryonic stem cells (ESCs) by direct differentiation using EC-conditioned medium (ECCM).ECCM-treated ESC-derived progenitor cells exhibited angiogenic potential, demonstrated by in vitro tubule formation, and endothelial-specific gene expression equivalent to natural EPCs.We concluded the effect of EPCs is cumulative and beneficial, relying on upregulation of the angiogenic activity of transplanted cells combined with an increase in proliferative cell number to produce significant effects upon transplantation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, UK. justin.stjohn@monash.edu.

ABSTRACT

Background: Endothelial progenitor cells (EPCs) are implicated in a range of pathological conditions, suggesting a natural therapeutic role for EPCs in angiogenesis. However, current angiogenic therapies involving EPC transplantation are inefficient due to rejection of donor EPCs. One solution is to derive an expanded population of EPCs from stem cells in vitro, to be re-introduced as a therapeutic transplant. To demonstrate the therapeutic potential of EPCs we performed in vitro transplantation of EPCs into endothelial cell (EC) tubules using a gel-based tubule formation assay. We also described the production of highly angiogenic EPC-comparable cells from pluripotent embryonic stem cells (ESCs) by direct differentiation using EC-conditioned medium (ECCM).

Results: The effect on tubule complexity and longevity varied with transplantation quantity: significant effects were observed when tubules were transplanted with a quantity of EPCs equivalent to 50% of the number of ECs originally seeded on to the assay gel but not with 10% EPC transplantation. Gene expression of the endothelial markers VEGFR2, VE-cadherin and CD31, determined by qPCR, also changed dynamically during transplantation. ECCM-treated ESC-derived progenitor cells exhibited angiogenic potential, demonstrated by in vitro tubule formation, and endothelial-specific gene expression equivalent to natural EPCs.

Conclusions: We concluded the effect of EPCs is cumulative and beneficial, relying on upregulation of the angiogenic activity of transplanted cells combined with an increase in proliferative cell number to produce significant effects upon transplantation. Furthermore, EPCs derived from ESCs may be developed for use as a rapidly-expandable alternative for angiogenic transplantation therapy.

No MeSH data available.


Related in: MedlinePlus

Endothelial expression following EPC transplantation. (A) VEGFR2, (B) VE-cadherin and (C) CD31 expression in 50% and 10% transplantation assays, relative to expression in 60% confluent ECs. Dotted line indicates expression in 60% confluent EPCs. Significant differences between transplantations indicated (*P < 0.05, **P < 0.01).
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Figure 8: Endothelial expression following EPC transplantation. (A) VEGFR2, (B) VE-cadherin and (C) CD31 expression in 50% and 10% transplantation assays, relative to expression in 60% confluent ECs. Dotted line indicates expression in 60% confluent EPCs. Significant differences between transplantations indicated (*P < 0.05, **P < 0.01).

Mentions: The effect of EPC transplantation on expression of VEGFR2, VE-cadherin and CD31 was assessed using qPCR. Prior to transplantation, expression patterns were equivalent to ECs grown on ECMatrix gels without transplantation. Following 50% transplantation, VEGFR2 expression increased significantly compared to non-transplanted ECs (P < 0.05; Figure 8a) but decreased continually following transplantation (6 h) until 14 h. VE-cadherin expression following 50% transplantation was not significantly different to non-transplanted ECs until 8 h when greater expression was detected (P < 0.05; Figure 8b). Although expression decreased from 8 h to 14 h it was still significantly greater at each time-point compared to control ECs (P < 0.05). CD31 expression was not altered significantly by 50% transplantation until 6 h, when greater expression was seen compared to control ECs (P < 0.05; Figure 8c). CD31 expression was greater than non-transplanted ECs until 14 h, at which time no significant difference was observed. 10% EPC transplantation did not result in significant changes in expression of VEGFR2, VE-cadherin or CD31 compared to non-transplanted ECs (P > 0.05).


Angiogenic potential of endothelial progenitor cells and embryonic stem cells.

Rae PC, Kelly RD, Egginton S, St John JC - (2011)

Endothelial expression following EPC transplantation. (A) VEGFR2, (B) VE-cadherin and (C) CD31 expression in 50% and 10% transplantation assays, relative to expression in 60% confluent ECs. Dotted line indicates expression in 60% confluent EPCs. Significant differences between transplantations indicated (*P < 0.05, **P < 0.01).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3108917&req=5

Figure 8: Endothelial expression following EPC transplantation. (A) VEGFR2, (B) VE-cadherin and (C) CD31 expression in 50% and 10% transplantation assays, relative to expression in 60% confluent ECs. Dotted line indicates expression in 60% confluent EPCs. Significant differences between transplantations indicated (*P < 0.05, **P < 0.01).
Mentions: The effect of EPC transplantation on expression of VEGFR2, VE-cadherin and CD31 was assessed using qPCR. Prior to transplantation, expression patterns were equivalent to ECs grown on ECMatrix gels without transplantation. Following 50% transplantation, VEGFR2 expression increased significantly compared to non-transplanted ECs (P < 0.05; Figure 8a) but decreased continually following transplantation (6 h) until 14 h. VE-cadherin expression following 50% transplantation was not significantly different to non-transplanted ECs until 8 h when greater expression was detected (P < 0.05; Figure 8b). Although expression decreased from 8 h to 14 h it was still significantly greater at each time-point compared to control ECs (P < 0.05). CD31 expression was not altered significantly by 50% transplantation until 6 h, when greater expression was seen compared to control ECs (P < 0.05; Figure 8c). CD31 expression was greater than non-transplanted ECs until 14 h, at which time no significant difference was observed. 10% EPC transplantation did not result in significant changes in expression of VEGFR2, VE-cadherin or CD31 compared to non-transplanted ECs (P > 0.05).

Bottom Line: We also described the production of highly angiogenic EPC-comparable cells from pluripotent embryonic stem cells (ESCs) by direct differentiation using EC-conditioned medium (ECCM).ECCM-treated ESC-derived progenitor cells exhibited angiogenic potential, demonstrated by in vitro tubule formation, and endothelial-specific gene expression equivalent to natural EPCs.We concluded the effect of EPCs is cumulative and beneficial, relying on upregulation of the angiogenic activity of transplanted cells combined with an increase in proliferative cell number to produce significant effects upon transplantation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, UK. justin.stjohn@monash.edu.

ABSTRACT

Background: Endothelial progenitor cells (EPCs) are implicated in a range of pathological conditions, suggesting a natural therapeutic role for EPCs in angiogenesis. However, current angiogenic therapies involving EPC transplantation are inefficient due to rejection of donor EPCs. One solution is to derive an expanded population of EPCs from stem cells in vitro, to be re-introduced as a therapeutic transplant. To demonstrate the therapeutic potential of EPCs we performed in vitro transplantation of EPCs into endothelial cell (EC) tubules using a gel-based tubule formation assay. We also described the production of highly angiogenic EPC-comparable cells from pluripotent embryonic stem cells (ESCs) by direct differentiation using EC-conditioned medium (ECCM).

Results: The effect on tubule complexity and longevity varied with transplantation quantity: significant effects were observed when tubules were transplanted with a quantity of EPCs equivalent to 50% of the number of ECs originally seeded on to the assay gel but not with 10% EPC transplantation. Gene expression of the endothelial markers VEGFR2, VE-cadherin and CD31, determined by qPCR, also changed dynamically during transplantation. ECCM-treated ESC-derived progenitor cells exhibited angiogenic potential, demonstrated by in vitro tubule formation, and endothelial-specific gene expression equivalent to natural EPCs.

Conclusions: We concluded the effect of EPCs is cumulative and beneficial, relying on upregulation of the angiogenic activity of transplanted cells combined with an increase in proliferative cell number to produce significant effects upon transplantation. Furthermore, EPCs derived from ESCs may be developed for use as a rapidly-expandable alternative for angiogenic transplantation therapy.

No MeSH data available.


Related in: MedlinePlus