Serum- and xeno-free culture of human umbilical cord perivascular cells for pediatric heart valve tissue engineering

Abstract

Background: Constructs currently used to repair or replace congenitally diseased pediatric heart valves lack a viable cell population capable of functional adaptation in situ, necessitating repeated surgical intervention. Heart valve tissue engineering (HVTE) can address these limitations by producing functional living tissue in vitro that holds the potential for somatic growth and remodelling upon implantation. However, clinical translation of HVTE strategies requires an appropriate source of autologous cells that can be non-invasively harvested from MSC-rich tissues and cultured under serum- and xeno-free conditions. To this end, we evaluated human umbilical cord perivascular cells (hUCPVCs) as a promising cell source for in vitro production of engineered heart valve tissue. Methods:The proliferative, clonogenic, multilineage differentiation, and extracellular matrix (ECM) synthesis capacities of hUCPVCs were evaluated in a commercial serum- and xeno-free culture medium (StemMACS™) on tissue culture polystyrene and benchmarked to adult bone marrow-derived MSCs (BMMSCs). Additionally, the ECM synthesis potential of hUCPVCs was evaluated when cultured on polycarbonate polyurethane anisotropic electrospun scaffolds, a representative biomaterial for in vitro HVTE. Results:hUCPVCs had greater proliferative and clonogenic potential than BMMSCs in StemMACS™ (p<0.05), without differentiation to osteogenic and adipogenic phenotypes associated with valve pathology. Furthermore, hUCPVCs cultured with StemMACS™ on tissue culture plastic for 14 days synthesized significantly more total collagen, elastin, and sulfated proteoglycans (p<0.05), the ECM constituents of the native valve, than BMMSCs. Finally, hUCPVCs retained their ECM synthesizing capacity after 14 and 21 days in culture on anisotropic electrospun scaffolds. Conclusion:Overall, our findings establish an in vitro culture platform that uses hUCPVCs as a readily-available and non-invasively sourced autologous cell population and a commercial serum- and xeno-free culture medium to increase the translational potential of future pediatric HVTE strategies.

Programmable Melt Electrowriting to Engineer Soft Connective Tissues with Prescribed, Biomimetic, Biaxial Mechanical Properties

“…Tensile properties of PCL were determined experimentally and used as an input to the computational model (Figure S1, Supporting Information). Using a full factorial DOE method, coupled with parametric modeling via linear regression, scaffold architecture was optimized to mimic the biaxial mechanical properties of three representative soft connective tissues (Figure 2): adult AV, [8] pediatric PV, [20] and pediatric PC (Figure S2, Supporting Information). The details of the DOE method, such as the design matrices (Tables S1 and S2, Supporting Information) are presented in Section S3 of the Supporting Information.…”

“…C) Biaxial mechanical properties of simulated scaffolds composed of 10 layers of orthogonally oriented sinusoidal fibers with optimized architecture (Sim.) and their respective native tissue (AV, [8] PV, [20] and PC, determined as described in the Supporting Information). Information), guaranteeing that polymeric scaffolds do not experience permanent deformation when undergoing physiological levels of strain (≤7% in the circumferential and ≤18% in the radial direction typically for heart valve tissue [8] ) or strain levels used to characterize the native tissues (Figure 2C).…”