Bioprinting for organ transplanting
From printing industrial prototypes to prosthetics and surgical
instruments, 3 D bioprinting technology shows excellent progress and
great promise in creating functional tissue and living organs
intermediate stage towards organ-level complexity. Despite the
limitations associated with biology and engineering, bioprinting holds
great promise in whole-organ printing with an excellent hierarchical
arrangement of cells and building tissue blocks in a 3D
microenvironment. To print a living tissue, cells are taken from either
a patient or adult stem cells and cultivated into a bioink. These
ingredients are held together through some sort of dissolvable gel or
scaffold, which can support the cells and mould them into the desired
shape. Current advanced imaging technology, such as computed tomography
(CT), enabled the creation of accurate CAD models for 3D printing to
ensure a perfect fit into the desired tissue [Vignesh et al 2017].
The bioprinted organ (organ blueprint) is printed by especially in
‘bioprinter friendly’ stereo lithography (STL) format, is basically
printed by dispensing the bioink with a computer-controlled, using
specific software, and placing layer on a layer using a dispensing
pumps. Printing body parts may well be the next step in organ
transplantation – harvesting stem cells from a transplant recipient and
printing them into a replacement organ could help bypass complications
associated with organ transplants such as long waits for a suitable
donor or immune rejection of the new organ. A number of breakthroughs in
3D bioprinting were demonstrated recently to create organ-level
structures including bone [Huang et al 2019], Cornea [Isaacson, et
al 2018], cartilage [Jeon et al 2019], heart [Noor et al 2019]
and skin [Baltazar et al 2019]. Fabrication of fully developed
vascularized organs would allow building functional/living human organ
constructs suitable for surgical implantation. However, achieving this
target still facing many challenges particularly, post-processing
remoldelling associated with tissue fusion, retraction and compaction of
the printed soft-tissue construct [Mironov et al 2008]. Therefore,
blueprint tissue/organs cannot be directly derived from clinical
scanning images. To get the desirable organ size and shape, CAD must
include experimentally estimated coefficients of specific tissue
compaction, retraction and remodelling [Mironov et al 2008].