Endothelialized ePTFE Graft by Nanobiotechnology

The replacement of autologous blood vessels by artificial grafts is urgently needed in clinical applications. Expanded polytetrafluoroethylene (ePTFE) grafts are the most clinically used artificial blood vessels because of its chemical and mechanical stability. But, when used as arteriovenous (AV) grafts for haemodialysis, small diameter ePTFE grafts have a high failure rate of 40% in three years in vivo because of the functional lack of an intact endothelial cell layer. Here we developed a two-step modification including chemical etching and plasma activation to enhance the hydrophilicity of ePTFE. Peptide motifs (eg. cyclic RRE, RGD) known to bind integrins on the endothelial cells were immobilized on ePTFE grafts. Functional peptide immobilization significantly increased the adherence and growth of HUVEC cells on ePTFEs. Patch ePTFE implantation in the pig's descending aorta was used to evaluate the in vivo endothelialization of these modified ePTFE grafts. At 28 days implantation, newly formed endothelial layers on peptide-immobilized ePTFE grafts were demonstrated by SEM and histological analysis. These preliminary data showed the potential to grow an intact endothelial layer to improve the patency rate of the modified ePTFE grafts.

Study Overview

• Status: Completed
• Conditions: The Apparatus for Processing the Tubular Graft Modification Will be Designed and Evaluated.; The On-site Capturing of the Endothelial (Progenitor) Cells by Peptide-mediated Selective Adhesion in Vitro and in Vivo Will Also be Elucidated.; The Patency Rate of ITRI-made Artificial Blood Vessels Will be Evaluated by the Porcine Animal Model.

• Study Type: Observational
• Enrollment (Actual): 6

Contacts and Locations

Study Locations

• Taiwan
  • Taipai, Taiwan
    • National Taiwan University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Native arteriovenous fistulas are not available in up to 40 percent of patients with renal dialysis. Therefore, the replacement of autologous blood vessels by artificial grafts is urgently needed. Expanded polytetrafluoroethylene( ePTFE) grafts are the most clinically used artificial blood vessels.

Description

Obtained from the peripheral blood leukocyte thick liquid (Hsinchu Blood Center, Taiwan Blood Services Fundation) Times - sampled 20 ~ 40ml / time, 2 to 3 times / month

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
EPCs; No proliferation and no differentiation on the ePTFEs
Modified ePTFE; EPCs adherence, proliferation and differentiation on the ePTFEs.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Isolate and expand EPCs from peripheral blood	Obtained from the peripheral blood leukocyte thick liquid (Hsinchu Blood Center, Taiwan Blood Services Fundation)	24 weeks

Collaborators and Investigators

• Sponsor: National Taiwan University Hospital
• Investigators: Principal Investigator: I Hui Wu, PhD, Cardiac Surgical Division, Surgical Department, National Taiwan University Hospital

Study record dates

Study Major Dates

• Study Start: September 1, 2010
• Primary Completion (Actual): September 1, 2010
• Study Completion (Actual): June 1, 2011

Study Registration Dates

• First Submitted: October 23, 2013
• First Submitted That Met QC Criteria: November 29, 2013
• First Posted (Estimate): December 5, 2013

Study Record Updates

• Last Update Posted (Estimate): December 5, 2013
• Last Update Submitted That Met QC Criteria: November 29, 2013
• Last Verified: November 1, 2013

More Information

Terms related to this study

• Keywords: Expanded polytetrafluoroethylene( ePTFE)
• Additional Relevant MeSH Terms: Pathologic Processes; Fibrosis; Cicatrix; Tissue Adhesions
• Other Study ID Numbers: 201009047R