Letter Regarding Article by Rotmans et al, “In Vivo Cell Seeding With Anti-CD34 Antibodies Successfully Accelerates Endothelialization but Stimulates Intimal Hyperplasia in Porcine Arteriovenous Expanded Polytetrafluoroethylene Grafts”

Abstract

To the Editor: Rapid (re)endothelialization of autologous and synthetic vascular grafts is regarded as a key element in reducing the risk of acute thrombosis and, by limiting adverse vessel wall remodeling, which includes intimal hyperplasia, preserving long-term patency. Rotmans et al1 (and the accompanying editorial2) challenge this tenet of vascular biology in their report of human anti-CD34 antibody–coated polytetrafluoroethylene (PTFE) grafts in a porcine AV fistula model. Rapid “endothelialization” of grafts is described, which, rather than improving functional outcome, was associated with significantly increased intimal hyperplasia at the venous anastomosis. The authors conclude that future studies will need to address a putative deficiency in the functional capability of captured endothelial progenitor cells (EPCs), highlighting approaches based on the use of regulatory proteins or alternative cell combinations. In our opinion, the data do not support these conclusions. The graft endoluminal cells were inadequately characterized with lectin (a surface antigen shared by several blood-borne …