Page 99 - IJB-9-1

International Journal of Bioprinting Progress in bioprinting of bone

for 7 days before being added into the hydrogel composite Acknowledgment
(containing fibrinogen, gelatin, HA, glycerol, HAp, VEGF,
basic fibroblast growth factor [bFGF], and aprotinin), which None.
was subsequently extruded. An array of droplets was deposited Funding
through drop-on-demand bioprinting of HUVECs-loaded
hydrogel composite (including fibrinogen, VEGF, bFGF, and This work was funded by the National Natural Science
aprotinin) after every second layer of ADSC-laden bioink Foundation of China (grant number 52205305), the
was printed. The bioprinted construct was enclosed by a GuangDong Basic and Applied Basic Research Foundation
PCL frame to ease transportation and was, then, implanted (grant number 2020A1515110724), and the Open
subcutaneously into mice. On 12-day implantation, large Foundation of the State Key Laboratory of Fluid Power and
volumes of calcified ECM, as well as blood vessels with lumens, Mechatronic Systems (grant number: GZKF-202004).
were observed. Table 3 summarizes the above-mentioned
studies on bone bioprinting using hybrid processes and the Conflict of interest
properties of the bioprinted bone constructs. The authors declare no potential conflicts of interest
concerning the research, authorship, and/or publication of
4. Conclusion and future prospects this article.
The advancement of bone bioprinting with the use of
various hydrogels, cell types, and other osteoconductive Author contributions
components has recently been remarkable, with several Conceptualization: Yang Wu
studies presenting mineralized structures with the Funding acquisition: Yang Wu
vascularized network. It takes a considerable period (until Visualization: Yang Wu, Ming Li
the healing and remodeling process is complete) to create Writing - original draft: Yang Wu, Ming Li, Hao Su
a durable structure with appropriate mechanical properties Writing - review & editing: Yang Wu, Ming Li, Hao Su,
and physiological functions, which requires a balance Huaying Chen, Yonggang Zhu
between bioink degradation and tissue regeneration [135] .
It is also challenging to develop large-scale vascularized References
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Volume 9 Issue 1 (2023) 91 https://doi.org/10.18063/ijb.v9i1.628