Bioengineering liver tissue by repopulation of decellularised scaffolds

Table 1 Examples of non-liver decellularisation protocols

Organ	Species	Decellularisation technique	Recellularization	Significant outcome	Ref.
Heart
	Rat	SDS + Triton X-100	Neonatal cardio-myocytes	(1) Maintained eight constructs for up to 28 d by coronary perfusion in a bioreactor that simulated cardiac physiology; (2) Macroscopic contractions were observed by day 4; and (3) By day 8, under physiological load and electrical stimulation, constructs could generate pump function in a modified working heart preparation.	Ott et al[235]
	Pig	Freeze and Thaw + hypotonic solution + trypsin/EDTA/NaN3 + Triton X-100/EDTA/NaN3 + deoxycholic acid	Chicken embryonic cardio-myocytes	Cardiac extracellular matrix supported the formation of organized chicken cardiomyocyte sarcomere structure in vitro.	Wainwright et al[236]
	Rat	SDS vs POETE	Not performed	SDS decreased DNA and GAG and enriched the collagen content 10-fold.	Bruyneel et al[237]
	Pig	SDS vs Triton X-100 vs CHAPS vs OGP	Not performed	3% SDS as a detergent showed optimal decellularization.	Ferng et al[238]
	Rat	SDS + Triton X-100	Induced cardiac progenitor cells	(1) Optical mapping of recellularised scaffolds shows field-stimulated calcium transients that propagate across islands; and (2) Bipolar local stimulation demonstrated cell-cell coupling within scaffolds.	Alexanian et al[239]
Kidney
	Rat	Saline + SNP + Triton X-100, DNAse + SDS	Murine pluripotent embryonic stem cells	(1) Primitive precursor cells populated and proliferated within the glomerular, vascular, and tubular structures; and (2) Cells lost their embryonic appearance and expressed immunohistochemical markers for differentiation.	Ross et al[240]
	Monkey	1% SDS vs 1% Triton X-100	Not performed	SDS at 48C to be most effective in preserving the native architecture.	Nakayama et al[241]
	Pig	0.5% SDS vs 0.25% SDS vs 1% Triton X-100 with 0.1% ammonium hydroxide	Not performed	0.5% SDS was the most effective detergent.	Sullivan et al[242]
	Pig	SDS	Not performed	(1) Kidney decellularized scaffolds implanted in Yorkshire pigs easily re-perfused, sustained blood pressure; (2) Scaffolds maintained renal ultrastructure; and (3) However, presence of inflammatory cells in the pericapsular region and complete thrombosis of the vascular tree were evident.	Orlando et al[243]
	Rat, pig, and human	SDS	HUVECs + Rat Neonatal kidney cells	(1) The resulting grafts produced rudimentary urine in vitro when perfused via their intrinsic vascular bed; and (2) Transplanted orthotopic grafts in rats, perfused by the recipient’s circulation, produced urine via the ureteral conduit in vivo.	Song et al[244]
	Pig	Sonication + SDS + Triton X-100	Not performed	(1) Significant decrease in decellularization time with sonication; and (2) Sonicator power proved to have significant effect on the microarchitecture integrity of the scaffold.	Manalastas et al[76]
Lung
	Rat	Heparinized PBS + SDS + Triton X-100	HUVECs	Orthotopic Transplantation of grafts with 6 h of perfusion in vivo.	Ott et al[245]
	Rat	PBS + SNP + CHAPS + EDTA + Benzonase	Rat neonatal lung epithelial + lung vascular endothelial cells	(1) In vitro, the mechanical characteristics of the engineered lungs were like those of native lung tissue; and (2) In vivo gas exchange for short time intervals (45 to 120 min).	Petersen et al[246]
	Mice	Triton X-100 + SDS + DNase	Embryonic stem cells	Demonstrated growth of foetal alveolar type II cells.	Price et al[247]
	Rat	Heparinized PBS + SDS + Triton X-100	HUVECs + rat foetal lung cells	Orthotopic transplantation of grafts with 7 d of perfusion in vivo.	Song et al[248]
Trachea
	Rabbit	Freeze/thaw + Sonication + SDS	Not performed	(1) Orthoptic transplantation od decellularized scaffolds into segmental tracheal defects in rabbits; (2) Respiratory epithelium regeneration on the inner surface; and (3) Cartilaginous tubular structures could not maintain structural integrity.	Hung et al[249]
	Pig	Freeze and Thaw + Agitation/immersion + SDS	Not performed	Successful decellularization.	Guimaraes et al[82]
	Rabbits	Sonication + 1 % SDS	Not performed	Orthotopic transplantation of partially decellularized trachea with no immunosuppression treatment resulted in 2 mo of survival in two rabbits and one long-term survival (2 years) in one rabbit.	Dang et al[71]
Nerve
	Human	Triton X-100 + SDS + EDTA + sonication	Not performed	Detergent and sonication more effective than detergent only.	Suss et al[74]
Small intestinal submucosa
	Pig	SDS/Triton X-100/DNase vs Agitation and immersion	Not performed	SDS/Triton X-100 combination for decellularization proved superior.	Syed et al[81]
Thyroid
	Rabbit	SDS + immersion/agitation	HTFC	The scaffolds exhibited good cytocompatibility, supported HTFCs growth, and proliferation.	Weng et al[85]

HTFC: Human thyroid follicular cells; SDS: Sodium dodecyl sulphate; HUVECs: Human umbilical vein endothelial cells.