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REVIEW ARTICLE

The trend towards in vivo bioprinting

1*
2
1
1,3
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Manyi Wang , Jiankang He , Yaxiong Liu , Meng Li , Dichen Li and Zhongmin Jin
1 State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an, 710054, China
2 The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710061, China
3 Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds LS2
9JT, UK

Abstract: Bioprinting is one of several newly emerged tissue engineering strategies that hold great promise in alleviat-
ing of organ shortage crisis. To date, a range of living biological constructs have already been fabricated in vitro using
this technology. However, an in vitro approach may have several intrinsic limitations regarding its clinical applicability
in some cases. A possible solution is in vivo bioprinting, in which the de novo tissues/organs are to be directly fabricated
and positioned at the damaged site in the living body. This strategy would be particularly effective in the treatment of
tissues/organs that can be safely arrested and immobilized during bioprinting. Proof-of-concept studies on in vivo bio-
printing have been reported recently, on the basis of which this paper reviews the current state-of-the-art bioprinting
technologies with a particular focus on their advantages and challenges for the in vivo application.
Keywords: bioprinting, in vivo, tissue engineering, regenerative medicine

*Correspondence to: Jiankang He, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an,
710054, China; Email: jiankanghe@mail.xjtu.edu.cn
Received: May 4, 2015; Accepted: May 26, 2015; Published Online: July 1, 2015
Citation: Wang M Y, He J K, Liu Y X, et al. 2015, The trend towards in vivo bioprinting. International Journal of Bioprinting, vol.
1(1): 15–26. http://dx.doi.org/10.18063/IJB.2015.01.001.

1. Introduction nozzle-based bioprinting systems are under parallel
I strategies, in which tissue/organ constructs are prefa- .
development, the majority of which are for in vitro
t is almost certain that the traditional organ trans-
plantation approach can never meet the mounting
[2–5]
bricated and cultured in vitro prior to implantation
global demands for tissue/organ replacement. One
of the most promising solutions to the organ shortage However, in vitro bioprinting may have several intrin-
sic limitations regarding its clinical applicability. Firstly,
crisis is tissue engineering (TE). Bioprinting, as one of even after setting aside several ethical issues which
several newly emerging TE strategies, is an attractive may limit the application of in vitro tissue/organ
additive manufacturing-based biotechnology which culture techniques, there is still a long way before
uses “bioinks” such as living cells, tissue spheroids, such technology becomes sophisticated and efficient
and bio-hydrogels to spatially construct 3D functional enough to synthesize functional tissue/organ replace-
structures without pre-fabricated scaffolds. The ulti- ments outside the body. Secondly, bioprinted tissue/
mate goal of bioprinting is to de novo synthesize tis- organ substitutes normally have weak initial mecha-
sues/organs that are suitable for complete restoration nical strengths due to the fluid-rich nature of the
of degenerated, damaged or lost ones. biomaterials used, hence handling and fixation of such
Like most newly emerging biotechnologies, bio- fragile living constructs to equally sensitive neigh-
printing was first introduced as an in vitro technique in boring native tissues, along with strict sterile require-
[1]
the laboratory . To date, laser-based, inkjet-based and ments on the entire routine (from in vitro fabrication,

The trend towards in vivo bioprinting. © 2015 Manyi Wang, et al. This is an Open Access article distributed under the terms of the Creative Commons
Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), permitting all non-commercial use, distribu-
tion, and reproduction in any medium, provided the original work is properly cited.
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