Gravity Spun Polycaprolactone Fibers for Applications in Vascular Tissue Engineering: Proliferation and Function of Human Vascular Endothelial Cells

Abstract

Poly(epsilon-caprolactone) (PCL) fibers produced by wet spinning from solutions in acetone under lowshear (gravity-flow) conditions resulted in fiber strength of 8 MPa and stiffness of 0.08 Gpa. Cold drawing to an extension of 500% resulted in an increase in fiber strength to 43 MPa and stiffness to 0.3 GPa. The growth rate of human umbilical vein endothelial cells (HUVECs) (seeded at a density of 5 x 10(4) cells/mL) on as-spun fibers was consistently lower than that measured on tissue culture plastic (TCP) beyond day 2. Cell proliferation was similar on gelatin-coated fibers and TCP over 7 days and higher by a factor of 1.9 on 500% cold-drawn PCL fibers relative to TCP up to 4 days. Cell growth on PCL fibers exceeded that on Dacron monofilament by at least a factor of 3.7 at 9 days. Scanning electron microscopy revealed formation of a cell layer on samples of cold-drawn and gelatin-coated fibers after 24 hours in culture. Similar levels of ICAM-1 expression by HUVECs attached to PCL fibers and TCP were measured using RT-PCR and flow cytometry, indicative of low levels of immune activation. Retention of a specific function of HUVECs attached to PCL fibers was demonstrated by measuring their immune response to lipopolysaccharide. Levels of ICAM-1 expression increased by approximately 11% in cells attached to PCL fibers and TCP. The high fiber compliance, favorable endothelial cell proliferation rates, and retention of an important immune response of attached HUVECS support the use of gravity spun PCL fibers for three-dimensional scaffold production in vascular tissue engineering.

Gelatine and Gelatine/Elastin Nanocomposites for Vascular Grafts: Processing and Characterization

“…Gelatine has also been used [26], presumably as a low cost alternative source of soluble collagen. Collagen and gelatine generally favour the attachment, proliferation and retention of cells and, hence, they have been used in several studies to coat other materials used for scaffolds, such as polycaprolactone [27].…”

Biomechanical Characterization of a Micro/Macroporous Polycaprolactone Tissue Integrating Vascular Graft

“…Gelatin coating of PCL fibers has previously been shown to improve fibroblast proliferation by a factor of 2 after 48 h in cell culture. 31 The data in Fig. 9 also indicates that a macropore size of 90-125 lm is advantageous for fibroblast growth on macroporous PCL materials.…”

“…Similar behavior was observed previously for 3T3 mouse fibroblasts cultured on PCL fibers. 31 Cell numbers were generally higher by a factor of two on macroporous PCL at day 5 and 8 compared with microporous material. However, the macroporous component is not anticipated to influence the number of attached cells due to the low macropore density at the material surface (Fig.…”

The Basement Membrane: Key to the Reverse Engineering Biological Tissues

“…Using 3D image data acquired using methods describe here and in previous works [64,65,67], we have shown that CAD tools can produce models designed for use in computer aided manufacturing (CAM) of tissue scaffolding ( Figure 6), not only for capillary bed systems and their connecting vasculature (Figure 1) [65], but to replicate as imaged from a sample from a specific organ system and manufacture using CAM a structural representation of unique cellular boundaries for specific tissue structures (Figures 5&6).…”