Editing Tissue engineering (section)

== Examples ==
[[File:Earproject - 2x3 (6127848729).jpg|thumb|Regenerating a human ear using a scaffold]]
As defined by Langer and Vacanti,<ref name="auto"/> examples of tissue engineering fall into one or more of three categories: "just cells," "cells and scaffold," or "tissue-inducing factors."
* [[In vitro meat]]: Edible artificial animal muscle tissue cultured ''in vitro''.{{cn|date=April 2025}}
* [[Bioartificial liver device]], "Temporary Liver", Extracorporeal Liver Assist Device (ELAD): The human [[hepatocyte]] cell line (C3A line) in a hollow fiber [[bioreactor]] can mimic the hepatic function of the liver for acute instances of liver failure. A fully capable ELAD would temporarily function as an individual's liver, thus avoiding transplantation and allowing regeneration of their own liver.{{cn|date=April 2025}}
* [[Artificial pancreas]]: Research involves using [[islet cell]]s to regulate the body's blood sugar, particularly in cases of [[diabetes]] . Biochemical factors may be used to cause human pluripotent stem cells to differentiate (turn into) cells that function similarly to [[beta cell]]s, which are in an [[islet cell]] in charge of producing [[insulin]].{{cn|date=April 2025}}
* Artificial [[Urinary bladder|bladders]]: [[Anthony Atala]]<ref>{{Cite web|url=https://www.wakehealth.edu/Providers/A/Anthony-Atala|title=Anthony Atala, MD|website=Wake Forest Baptist Health}}</ref> ([[Wake Forest University]]) has successfully implanted artificial bladders, constructed of cultured cells seeded onto a bladder-shaped scaffold, into seven out of approximately 20 human test subjects as part of a [[long-term experiment]].<ref name="cnngrow">{{cite news |url=http://www.cnn.com/2006/HEALTH/conditions/04/03/engineered.organs/index.html |title=Doctors grow organs from patients' own cells |work=CNN |date=3 April 2006}}</ref>
* [[Cartilage]]: lab-grown cartilage, cultured ''in vitro'' on a scaffold, was successfully used as an [[autotransplantation|autologous]] transplant to repair patients' knees.<ref name="knee">{{cite news |url=https://www.newscientist.com/article/dn9483-lab-grown-cartilage-fixes-damaged-knees/ |title=Lab-grown cartilage fixes damaged knees |date=5 July 2006 | vauthors = Simonite T |work=New Scientist}}</ref>
* Scaffold-free cartilage: Cartilage generated without the use of exogenous scaffold material. In this methodology, all material in the construct is cellular produced directly by the cells.<ref name="BioResearch Open Access 2012" >{{cite journal | vauthors = Whitney GA, Mera H, Weidenbecher M, Awadallah A, Mansour JM, Dennis JE | title = Methods for producing scaffold-free engineered cartilage sheets from auricular and articular chondrocyte cell sources and attachment to porous tantalum | journal = BioResearch Open Access | volume = 1 | issue = 4 | pages = 157–65 | date = August 2012 | pmid = 23514898 | pmc = 3559237 | doi = 10.1089/biores.2012.0231 }}</ref>
* [[Bioartificial heart]]: [[Doris Taylor]]'s lab constructed a [[Biocompatibility|biocompatible]] rat heart by re-cellularising a de-cellularised rat heart. This scaffold and cells were placed in a [[bioreactor]], where it matured to become a partially or fully transplantable organ.<ref>{{cite journal | vauthors = Ott HC, Matthiesen TS, Goh SK, Black LD, Kren SM, Netoff TI, Taylor DA | title = Perfusion-decellularized matrix: using nature's platform to engineer a bioartificial heart | journal = Nature Medicine | volume = 14 | issue = 2 | pages = 213–21 | date = February 2008 | pmid = 18193059 | doi = 10.1038/nm1684 | s2cid = 12765933 }}</ref> the work was called a "landmark". The lab first stripped the cells away from a rat heart (a process called "[[decellularization]]") and then injected rat stem cells into the decellularized rat heart.<ref>{{cite news | vauthors = Altman LK |newspaper=The New York Times |date=13 January 2008 |url=https://www.nytimes.com/2008/01/13/health/13cnd-heart.html |title=Researchers Create New Rat Heart in Lab}}</ref>
* Tissue-engineered [[blood vessel]]s:<ref>{{cite book | vauthors = Zilla P, Greisler H |title= Tissue Engineering of Vascular Prosthetic Grafts |publisher= R.G. Landes Company |date= 1999 |isbn= 978-1-57059-549-3}}{{page needed|date=July 2021}}</ref> Blood vessels that have been grown in a lab and can be used to repair damaged blood vessels without eliciting an [[immune response]].  Tissue engineered blood vessels have been developed by many different approaches.&nbsp; They could be implanted as pre-seeded cellularized blood vessels,<ref>{{cite journal | vauthors = Naegeli KM, Kural MH, Li Y, Wang J, Hugentobler EA, Niklason LE | title = Bioengineering Human Tissues and the Future of Vascular Replacement | journal = Circulation Research | volume = 131 | issue = 1 | pages = 109–126 | date = June 2022 | pmid = 35737757 | pmc = 9213087 | doi = 10.1161/CIRCRESAHA.121.319984 }}</ref> as acellular vascular grafts made with [[decellularized]] vessels or synthetic [[vascular graft]]s.<ref>{{cite journal | vauthors = Chang WG, Niklason LE | title = A short discourse on vascular tissue engineering | journal = npj Regenerative Medicine | volume = 2 | issue = 1 | pages = 1–8 | date = 2017-03-27 | pmid = 29057097 | doi = 10.1038/s41536-017-0011-6 | pmc = 5649630 }}</ref>
* [[Artificial skin]] constructed from human skin cells embedded in a [[hydrogel]], such as in the case of bio-printed constructs for battlefield burn repairs.<ref>{{Cite web|url=http://www.microfab.com/index.php?option=com_content&view=article&id=78:tissue-engineering&catid=12:biomedical-apps&Itemid=141#burnRepairs|title=Tissue Engineering|website=microfab.com}}</ref>
* Artificial [[bone marrow]]: Bone marrow cultured ''in vitro'' to be transplanted serves as a "just cells" approach to tissue engineering.<ref>{{cite news |title=Bone in a bottle: Attempts to create artificial bone marrow have failed until now |url=http://www.economist.com/science/tm/displayStory.cfm?story_id=12883495&source=hptextfeature |newspaper=The Economist |date=7 January 2009}}</ref>
* Tissue engineered bone: A structural matrix can be composed of metals such as titanium, polymers of varying degradation rates, or certain types of ceramics.<ref name=aa>{{cite journal | vauthors = Amini AR, Laurencin CT, Nukavarapu SP | title = Bone tissue engineering: recent advances and challenges | journal = Critical Reviews in Biomedical Engineering | volume = 40 | issue = 5 | pages = 363–408 | date = 2012 | pmid = 23339648 | pmc = 3766369 | doi = 10.1615/critrevbiomedeng.v40.i5.10 }}</ref> Materials are often chosen to [[Bone grafting|recruit osteoblasts]] to aid in reforming the bone and returning biological function.<ref>{{Cite journal | vauthors = Thomas D |date=2021-04-16 |title=3D printing cross-linkable calcium phosphate biocomposites for biocompatible surgical implantation |journal=Bioprinting |volume=22 |pages=e00141 |doi=10.1016/j.bprint.2021.e00141 |s2cid=234851322 |issn=2405-8866}}</ref> Various types of cells can be added directly into the matrix to expedite the process.<ref name=aa/>
* [[Penis transplantation#Laboratory-grown penises|Laboratory-grown penis]]: Decellularized scaffolds of rabbit penises were recellularised with smooth muscle and endothelial cells. The organ was then transplanted to live rabbits and functioned comparably to the native organ, suggesting potential as treatment for [[genital trauma]].<ref>{{cite web|title=Artificial Penis Tissue Proves Promising in Lab Tests|url=http://www.livescience.com/health/091109-artificial-penis-tissue-rabbits.html |work=Live Science | vauthors = Choi CQ |date=9 November 2009}}</ref>
* [[Oral mucosa tissue engineering]] uses a cells and scaffold approach to replicate the 3 dimensional structure and function of [[oral mucosa]].{{cn|date=April 2025}}