Utilizing the Foreign Body Response to Grow Tissue Engineered Blood Vessels in Vivo

Abstract

It is well known that the number of patients requiring a vascular grafts for use as vessel replacement in cardiovascular diseases, or as vascular access site for hemodialysis is ever increasing. The development of tissue engineered blood vessels (TEBV’s) is a promising method to meet this increasing demand vascular grafts, without having to rely on poorly performing synthetic options such as polytetrafluoroethylene (PTFE) or Dacron. The generation of in vivo TEBV’s involves utilizing the host reaction to an implanted biomaterial for the generation of completely autologous tissues. Essentially this approach to the development of TEBV’s makes use of the foreign body response to biomaterials for the construction of the entire vascular replacement tissue within the patient’s own body. In this review we will discuss the method of developing in vivo TEBV’s, and debate the approaches of several research groups that have implemented this method.

A novel method for engineering autologous non-thrombogenic in situ tissue-engineered blood vessels for arteriovenous grafting

“…Later, Campbell further developed this concept by using the peritoneal cavity as the in vivo bioreactor [43]. As the knowledge regarding modulation of the FBR increased, this so-called mandril-based method has been fine-tuned and strengthened [8].…”

“…A wide range of tissue-engineering approaches have been suggested for replacing synthetic grafts [7]. One such method involves the socalled mandril-based approach, which relies on the foreign body response (FBR) driving the development of an autologous in vivo cellularized vascular substitute surrounding an implanted medical device [8]. Using both in vivo [9,10] and in vitro [11] approaches, we previously reported that the implant's surface characteristics can influence the resulting FBR, thereby affecting the composition of the tissue that forms around the implant.…”

In Situ Generated Medical Devices

“…V) Over time remodeling occurs, where the TEBV transdifferentiates to attain characteristics of a native blood vessel. Reproduced with permission . Copyright 2017, Springer Nature.…”

“…Additionally, the patency of the grafts formed was limited by the occurrence of frequent thrombotic phenomena and the stenotic blockage of the vascular graft. Furthermore, the tubular tissue construct that was formed showed suboptimal mechanical properties and resulted in around a 20% rate of aneurysm formation …”

Tissue Engineering—Bridging the Gap

“…The experimental studies in this issue address a variety of topics within the heart valve field including two papers on the development of decellularised valves [5,6], the chemical fixation of bovine pericardium and the assessment of a new transcatheter heart valve [7,8]. Within the vascular field, there are two papers, the first addresses the use of an in vivo approach that utilises the host reaction to an implanted biomaterial for the generation of completely autologous tissues, while the second examines the use of intravascular echo as a tool to evaluate the changes within tissue-engineered valves implanted into sheep [9,10]. Engineered tissues can also be used to mimic and study normal and diseased conditions.…”