What’s Organ printing? What’s Bioprinting? Does organ printing really mean what it says in itself?? Pr-in-ting organs? What do these technologies have to offer? What would the implications of these technologies be on the state of the industry, the general public and the entire humanity? Let’s just break the fourth wall here. Who’s asking??
Well…To clarify, we are asking these questions in the interest of and to interest the general public and if the latter isn’t lost already (we earnestly hope that is the case) please read up…
Creating living tissue in complex geometries is a challenging issue facing the tissue engineering community. Traditional tissue engineering techniques result in living tissue of simple, often 2D geometries. By harnessing the capabilities of Solid-Freeform Fabrication (SFF) – also known as Rapid Prototyping (RP) –living tissue of arbitrary 3D shapes can be created directly from computer-aided design (CAD) data.
Bio-printing is a variant of 3D printing and can be defined as computer-aided, automatic, layer-by-layer deposition, transfer, and patterning of biologically relevant materials. It is also known by other names such as “computer aided tissue engineering” and “biofabrication”. In simpler words, bioprinting involves printing devices that deposit biological material.
Organ printing is a variant of bio-printing aiming at producing 3D organs. This is among the most promising advances of regenerative medicine. The 3D- Bioprinter was listed among the TIME magazine’s 50 best inventions of 2010. Most of the 3D printers use a modified version of inkjet printers to deposit dots of “bio ink” (cell suspension with 10 to 30 thousand cells per drop) that coalesce to form layers of organ interrupted by layers of biopaper (hydrogel mimicking the microenvironment of tissue) which is water-soluble.
Fig1:- Step-by-Step process of Organ Printing 
Roadmap to Bioprinting
Fig 2:- Roadmap to Bioprinting 
The 3D bioprinters currently in the market are produced by envisionTEC, Organovo, Tengion, Sciperio, Neatco, etc.
The NovoGen MMX 3D Bioprinter, priced at $200,000, has been developed by Organovo, a company in San Diego that specializes in regenerative medicine, and Invetech, engineering and automation firm in Melbourne, Australia. One of the founders of Organovo, Gabor Forgacs from the University of Missouri, Columbia, says the logic behind applying 3D printing for producing biological organs is “Although morphogenetic processes are under strict genetic control, genes do not create shapes and forms: physical mechanisms and processes do.” Organovo announced the production of first fully bioprinted blood vessels in Dec 2010. 
Organovo’s only real competitor, Tengion, holds most of the patents and legal rights to exploit the technology developed by the most successful bio printing scientist to date, Dr. Anthony Atala. Dr. Atala’s lab has grown a variety of human parts including blood vessels, heart valves and bladders, all using bio printing. Based on the same 3D print technology that Organovo uses, Tengion’s prototype printer has already produced several bladders which have been successfully transplanted into humans.
The 3D Bioplotter is produced by German company envisionTEC is a German company producing a range of 3D bioprinters such as 3D Bioplotter, E-Dent (Digital Dental printer), etc. The 3D Bioplotter is priced at $188,000 and currently used in various laboratories to create various tissue scaffolds. 
Work of other research groups on Bioprinting:-
Boland and his coworkers from Clemson University have been producing Bioprinters since 2004.
VAXDesign of Sciperio Inc has a pressure operated 3D Bioprinter with four nozzles in the market.
Roland, Fishman, and Neatco collaboratively produce a pressure operated 3D Bioprinter with two nozzles. 
Professor Nakamura from the University of Toyama is currently working with Epson to produce 3D Bioprinters.
Sangeeta Bhatia from MIT together with Jennifer West from Rice University bioprinted living 3D liver constructs using stereolithography.
Tsinghua University group in China also printed liver construct using chitosan-collagen hydrogel.
A research group at Cornell University bioprinted living cartilage construct. 
The Bioprinting community meets annually at the International Conference on Bioprinting and Biofabrication. The next conference (the sixth) is to be held in Toyama, Japan in October 2011.
Future and Implications:-
Professor Vladimir Mironov, Director of Medical University of South Carolina(MUSC) , Bioprinting Center says that it would probably take an investment of $1 billion to print living human organ suitable for clinical implantation.
Also, Dr. Atala says in vivo bioprinting i.e.; bioprinting right into a patient on the site of injury is very much feasible.
As Chair of The Department of Surgery of Stanford University and a leading expert in surgical innovation, Krummel recently wrote: “There is no such thing as a science fiction. There is only science eventuality”. 
Here’s to a future when Organ transplantation is hassle-free, affordable, automated, and customized.
Ajay S and Jnanasiddhy