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3D-printed Stent Coated with Dipyridamole-loaded Nanofiber
coated with PDLLA/DP nanofibers could inhibit the
proliferation of SMC and had no detrimental effects
on endothelial cells in vitro. Furthermore, the in vivo
A B
implantation of stents coated with PDLLA/DP nanofibers
showed initial patency and continuous endothelialization
and alleviated neointimal formation compared to bare
stents. Collectively, the integrated stents coated with DP-
loaded PDLLA nanofibers showed great potential for
restenosis prevention and endothelialization. In future
research, the decrease in strut thickness and the long-term
in vivo implantation of improved stents will be further
explored.

Acknowledgments
The authors acknowledge funding support from the
Tsinghua University Initiative Scientific Research
Program (20197050024) and the 111 Project (B17026).
Conflicts of interest
Figure 8. Immunohistochemical analysis of the stented arterial
segments for CD31 after implantation for 28 days. (A) Bare stents No conflict of interest was reported by all authors.
and (B) stents coated with dipyridamole-loaded poly(D,L-lactide)/
DP nanofibers. Author contributions
with the guidance of the 3Rs principle (replace, reduce, C. W., L. Z., and W. S. proposed the integrated stent
and refine), we only retained the “Stent” group as a control design and prepared the manuscript. C. W., Y. Y., and J.
group to reduce the number of experimental animals as J. conducted the experiments. Y. F. and L. O. helped to
revise the manuscript. All authors have given approval to
much as possible. After implantation for 28 days, arteries
implanted with DP-loaded stents were observed with a the final version of the manuscript.
reduction in intimal hyperplasia, the average neointimal References
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92 International Journal of Bioprinting (2022)–Volume 8, Issue 2