Design and characterization of small-diameter tissue-engineered blood vessels constructed by electrospun polyurethane-core and gelatin-shell coaxial fiber

Abstract

Substitution or bypass is the most effective treatment for vascular occlusive diseases.The demand for artificial blood vessels has seen an unprecedented rise due to the limited supply of autologous blood vessels. Tissue engineering is the best approach to provide artificial blood vessels. In this study, a new type of small-diameter artificial blood vessel with good mechanical and biological properties was designed by using electrospinning coaxial fibers. Four groups of coaxial fibers vascular membranes having polyurethane/gelatin core-shell structure were cross-linked by the EDC-NHS system and characterized. The core-shell structure of the coaxial vascular fibers was observed by transmission electron microscope. After the crosslinking, the stress and elastic modulus increased and the elongation decreased, burst pressure of 0.11 group reached the maximum (2844.55 ± 272.65 mmHg) after cross-linking, which acted as the experimental group. Masson staining identified blue-stained ring or elliptical gelatin ingredients in the vascular wall. The cell number in the vascular wall of the coaxial group was found in muscle embedding experiment significantly higher than that of the non-coaxial group at all time points (p < 0.001). Our results showed that the coaxial vascular graft with the ratio of 0.2:0.11 had better mechanical properties (burst pressure reached 2844.55 ± 272.65 mmHg); Meanwhile its biological properties were also outstanding, which was beneficial to cell entry and offered good vascular remodeling performance. Polyurethane (PU); Gelatin (Gel); Polycaprolactone (PCL); polylactic acid (PLA);1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC); N-Hydroxy succinimide (NHS); 4-Morpholine-ethane-sulfonic (MES); phosphate buffered saline (PBS); fetal calf serum (FCS); Minimum Essential Medium (MEM); Dimethyl sulfoxide (DMSO); hematoxylineosin (HE).

3D-Bioprinted Biomimetic Multilayer Implants Comprising Microfragmented Adipose Extracellular Matrix and Cells Improve Wound Healing in a Murine Model of Full-Thickness Skin Defects

“…H&E staining showed the homogeneously implanted collagen and muscle fibers in the wound in light pink and red, which could not be used to distinguish the collagen components and muscle fibers. We can distinguish collagen fibers from muscle fibers by MT staining because this method can stain muscle fibers red and collagen and gelatin fibers blue . MT staining showed that the collagen and gelatin contained in the implants were more homogeneous and showed a greater degree of aggregation and continuity than the collagen newly produced in the wound (Figure ).…”

“…We can distinguish collagen fibers from muscle fibers by MT staining because this method can stain muscle fibers red and collagen and gelatin fibers blue. 64 MT staining showed that the collagen and gelatin contained in the implants were more homogeneous and showed a greater degree of aggregation and continuity than the collagen newly produced in the wound (Figure 11). We can distinguish the implanted collagen from the native collagen based on these characteristics.…”

Construction of spider silk protein small‐caliber tissue engineering vascular grafts based on dynamic culture and its performance evaluation

“…After implantation, ideal small‐caliber tissue‐engineered blood arteries should be able to form new functional tissues. Furthermore, in vivo regenerated vascular grafts should have the structure and function of MSCs and ECs similar to the autogenous artery 52,53 . Graft leakage can occur throughout the graft length and can be stopped by hemostatic compression after re‐establishing blood flow.…”

“…Furthermore, in vivo regenerated vascular grafts should have the structure and function of MSCs and ECs similar to the autogenous artery. 52,53 Graft leakage can occur throughout the graft length and can be stopped by hemostatic compression after re-establishing blood flow. In addition, mechanical deterioration caused by host cell recellularization and polymer imbalance on vascular grafts may also lead to graft leakage and expansion.…”

Preparation and performance of random- and oriented-fiber membranes with core–shell structures via coaxial electrospinning

“…Fibrous scaffolds prepared by electrospinning are capable of mimicking the complex structure of a natural extracellular matrix ( Hasan et al, 2014 ; Ingavle and Kent, 2014 ; Kishan and Hernandez, 2017 ; Zong et al, 2018 ; Eilenberg et al, 2020 ), and they have large specific surface areas and a high-porosity microstructures that facilitate cell and nutrient infiltration ( Yin et al, 2020a ; Guo et al, 2022 ). The method of coaxial electrospinning can prepare functional fiber membranes ( Ezhilarasu et al, 2019 ; Johnson et al, 2021 ; Zhang et al, 2021 ). Materials can be loaded inside the fiber to enhance the mechanical properties or regulate material degradation.…”