A polydioxanone electrospun valved patch to replace the right ventricular outflow tract in a growing lamb model

Polymer-Based Reconstruction of the Inferior Vena Cava in Rat: Stem Cells or RGD Peptide?

“…Initial proof-of-principle experiments entailing the placement of a mesenchymal stem cell-seeded PDO monocusp patch across the pulmonary annulus in growing lambs confirmed the high biocompatibility of this polymer which, over time, was replaced by a host-derived tissue histologically similar to the native pulmonary arterial wall. 12 This result is consistent with the successful outcomes yielded by PDO valvular rings implanted in children. 30 However, a drawback of PDO in our experiments was its fast degradation that led us to compare it, in a head-to-head fashion, with two other polymers (PU and PHBVV).…”

“…Another important finding from the previous work of our laboratory and others 12,[16][17][18] is that polymer-seeded cells are cleared over time, which leads to speculate that the grafted cells do not structurally integrate within the neovessel wall, but rather act as platforms releasing signalling molecules that may recruit host cells. This hypothesis provides a robust rationale for testing whether cells can, thus, be replaced by biomimetic compounds, which could duplicate their recruiting effects and promote self-healing.…”

“…12 As part of a move toward a valved tube, we then completed this two-stage study. First, a head-to-head comparison was performed between a PDO (taken as our reference) and two other polymers, polyhydroxyalkanoate (PHA) and polyurethane (PU), which have already been used in cardiovascular research with encouraging results in terms of endothelialization and biocompatibility.…”

“…First, a head-to-head comparison was performed between a PDO (taken as our reference) and two other polymers, polyhydroxyalkanoate (PHA) and polyurethane (PU), which have already been used in cardiovascular research with encouraging results in terms of endothelialization and biocompatibility. 10,11,[13][14][15] In the second step, we leveraged previous findings from our laboratory 12 and others [16][17][18] showing that cells seeded onto polymers implanted in the circulation are rapidly cleared and compared two functionalization modalities of the polymer patch based on cell seeding and peptide grafting, respectively. To this end, we selected adipose-derived stem cells (ADSCs) and the tripeptide arginine-glycine-aspartate (RGD) with the premise that this motif, which has a long-standing efficacy record in biomaterial functionalization, 19,20 might allow scaffold repopulation from the host cells.…”

Isolation, Characterization and Differentiation Potential of Cardiac Progenitor Cells in Adult Pigs

“…Sheep is often used to study the possibility to use MSC for cardiac valve regeneration in association with bioabsorbable valved patches (Kalfa et al 2010;Sutherland et al 2005). Bone marrow mononuclear cells (BMMC) have been used to create in vitro tissue-engineered heart valves based on a decellularized porcine scaffold then tested in autologous transplantats (Vincentelli et al 2007).…”