## 4 Discussion  
The execution of the physiological function of various cell types is regulated not only by the biological signals, but also by the ECM and the surrounding cells [39]. A wide array of scaffold designs share a common objective: constructing an ideal structure that resembles the ECM of native tissues. The electrospinning process represents a straightforward, efficient, versatile, cost-effective approach that is capable of generating nanometer-scale non-woven fibrous structures, making it particularly suitable for applications such as wound dressing and tissue engineering [16; 40]. A three-dimensional (3D) scaffold, when constructed from nanofibers, is expected to yield a biomimetic structure that is akin to the ECM [41]. Cell attachment to materials serves as a fundamental precursor to various other cellular phenomena, including proliferation, spreading, migration, and differentiation. In this study, hG-MSCs exhibited recognition and attachment to three different materials. After 3 days of cell seeding, cells demonstrated enhanced and accelerated spreading on GPP in comparison to the collagen matrix; meanwhile, the formation of filopodia by cells growing on the surface of GPP further confirmed the presence of a substantial contractile force facilitating the cell migration (Figure 4). Consistent with the current  
Figure 5: Protein production by hG-MSCs grown on different materials. The protein production of VEGF-A (**a**), TGF-\(\beta\)1 (**b**), and IL-8 (**c**) in the cells cultured on different materials for 3, 7, and 14 days was quantified by ELISA. Y-axes show the concentration of target protein in conditioned media. The data from five donors are displayed as the mean \(\pm\) SD. Differences between groups at the same time point are indicated by * and ** for \(p<0.05\) and \(p<0.01\), respectively. Cells grown on VSCM presented the highest expression level of VEGF-A. VSCM showed a more significant upregulation in the production of IL-8 after 3 and 14 days. There was no significant difference in the production of TGF-\(\beta\)1 among the three groups. data, [PERSON] et al. substantiated that nanofiber materials comprising different PCL/GE ratios displayed desirable morphology and adhesion of human bone marrow-derived MSCs [42]. In contrast to VSCM, GPP manifested a notable occurrence of cells joining together and/or overlapping. This observation indicated that the cells were engaging in interactions with one another. However, a prior study demonstrated some disparities, revealing that collagen nanofiber exhibited notably better cytocompatibility with mouse fibroblasts when compared to GE nanofiber [43]. One potential reason could be that electrospun GPP possesses a higher density of Arg-Gly-Asp (RGD) cell-binding sites compared to reconstituted VSCM [11; 17; 30]. In addition, nanometer-scale fibers could be more conducive to promoting cell attachment and extension than micrometer-scale materials [44]. This may provide another explanation for why nanoscale GPP presented different cell adhesion to micro-scale VSCM. Cell proliferation and viability are also pivotal factors to consider when determining the biocompatibility and suitability of a scaffold for tissue regeneration. The CCK8 test was conducted to assess the proliferation/viability of hG-MSCs on different substrates. Although GPP exhibited inferior capabilities compared to the positive control group, the number of cells growing on it increased continuously over 2 weeks (Figure 2). These outcomes are coherent with numerous previous studies, which indicated that fibroblasts, osteoblasts, and cardiac muscle cells all exhibited favorable non-toxicity and high proliferation rates on PCL/GE electrospinning scaffolds [29; 41; 45]. Curiously, the proliferation of cells seeded on VSCM appeared to remain unchanged during the first week, indicating the delayed growth of hG-MSCs on this substrate. The data on the metabolic activity of the cells generally affirmed this conclusion.