3.4 In vitro biological performance of bilayer scaffolds
Many in vitro and in vivo studies have demonstrated the
safety and efficacy of menstrual-derived stem cells (MenSCs) obtained
from women’s menstrual fluids for repairing damaged uterine tissues[45]. Although MenSCs attract growing interest in
clinical applications because they are multipotent and have high
proliferation rate, the limited source and complex extraction procedure
is problematic. A recent study has indicated that BMSCs had comparable
properties as MenSCs had [46], suggesting that
BMSCs could replace MenSCs for use in uterine regeneration.
Additionally, many studies have demonstrated the efficacy of BMSCs for
uterine regeneration in preclinical and clinical trials. BMSCs could
differentiate into endometrium epithelial cells so as to improve gland
and blood vessel formations and activate the resident endometrium stem
cells to promote uterine regeneration via the paracrine effect[10b, 47]. Therefore, in the current study, BMSCs
were used to evaluate the in vitro biological performance of
bilayer scaffolds. Cell attachment results, as shown in Fig.S13,
revealed that BMSCs cultured on S, S+F and S+F-PDA@E2 scaffolds all
exhibited spread morphology, suggesting that all scaffolds were
biocompatible. The live/dead assay results indicated that the BMSC
survival rate in S, S+F and S+F-PDA@E2 scaffolds was over 90 % after
cultured for 24 and 48 h, respectively [Fig.7(A)(B)]. However, the
proliferation rates of BMSCs on those scaffolds were significantly
different [Fig.7(C)]. Compared to S scaffolds (i.e., PTMC/TPU), S+F
bilayer scaffolds and S+F-PDA@E2 bilayer scaffolds had higher
proliferation rates, suggesting that electrospun PLGA/GelMA fibers on
PTMC/TPU scaffolds had made scaffold surface hydrophilic and improved
scaffold-cell interface behavior and thus promoted cell proliferation.
Moreover, due to the PDA particles and sustained release of E2,
S+F-PDA@E2 bilayer scaffolds had the highest proliferation rate, which
was consistent with previous studies [40a, 44].
Furthermore, phalloidin/DAPI staining results in Fig.7(D) indicated that
BMSCs maintained their phenotypes and showed spindle-like morphology on
S+F and S+F-PDA@E2 bilayer
scaffolds. Overall, S+F-PDA@E2 bilayer scaffolds had excellent
biocompatibility and promoted BMSC growth.