Introduction
According to U.S. government information on organ donation and transplantation, statistics done by HRSA (health resources and services administration) more than 109,000 patients including men, women, children are on the national transplant waiting list as of September 2020. Only 39,718 transplants were performed in 2019 and 17 people die each day waiting for an organ transplant, every 9 minutes count is increased in the organ transplant waiting list.
These are just the statistical data for organ transplants required in the U.S., but the numbers of organ transplants required worldwide are manifolds, and to get all these organ transplants there are not enough donors.
Bio-printing is a transpiring technology for creating and fabricating biological tissues, organs, and cells for medical and biotechnology purposes. Bio-printing will be a thaumaturgy in the field of medical science giving Homo sapiens an extra edge to a prolonged healthy life.
Bio-printing of an organ as a whole will eliminate the need of the donors and will grant the recipients a second chance at life.
Section 1: Bio Printing
Defining “Bio-printing”: It is defined as developing new organs and tissues with a CAD-CAM (computer-aided design and computer-aided manufacturing) process synchronously generating and stacking living cells and biomaterials with a stipulated layering of these cells into bio-constructs using them for tissue engineering, regenerative medicine, and other biological studies.[1][2]
Evolution of Bio-printing: The development of fully functional organs by bio-printing is an evasive and ongoing process. There is a cornucopia of research going on for bio-printing fully working organs that can be used for organ transplants. Klebe in 1988 was the first to demonstrate cyto-scribing technology which is a form of bio-printing. A timeline of bio-printing evolution is illustrated in table 1.1
| YEAR | EVOLUTION |
| 1988 | 2D micro-positioning of cells using cyto-scribing technology. |
| 1996 | The observation that cells stick together and move together in clumps. |
| 1996 | The first use of natural biomaterial in a human |
| 1998 | The invention of cell sheet technology |
| 1999 | Laser direct-write(LDW) |
| 2001 | First tissue-engineered bladder |
| 2002 | Bio-printing using inkjet technology |
| 2003 | Inkjet printing creates functional cells |
| 2004 | Inkjet cell dispensing |
| 2004 | 3D tissue without scaffolding |
| 2006 | Fabrication of 3D bovine aorta |
| 2007 | Digital printing |
| 2008 | The idea of tissue spheroids as building blocks |
| 2009 | 1st commercial bioprinter (Novogen MMX) |
| 2009 | Vascular constructs- scaffolding free |
| 2010 | Successful patterning of hepatocytes in collagen using LDW |
| 2012 | Skin printing in-situ |
| 2012 | Repairing human cartilage using inkjet printing |
| 2012 | Bipolar wave-based drop-on-demand jetting |
| 2012 | Extrusion based bio-printing for engineering artificial liver |
| 2014 | Multi-arm bio-printer in tissue fabrication with printed vasculature |
| 2016 | Large scale bio-printing of perfusable tissue constructs |
The use of next-generation bio-printers and perfusable tissue models in fabricating fully vascularised hybrid tissues will take the organ and tissue printing to a next level. Bio-printing is a miraculous part of science that is advancing day by day, with a plethora of research going on all over the globe, but mastering it is still a long way to go.[2]
Classification of bio-printing: The most advanced technologies used in bio-printing consists of self-assembly, self-stacking, self-organizing of cells and tissue through commanding application techniques, these techniques can be differentiated into three:
Extrusion-based Bio-printing It is a coalescence of fluid dispensing and robotic automation systems for extrusion and bio-printing simultaneously.
Droplet-based Bio-printing In this procedure of bio-printing diverse sources of energies like sound, heat, electricity is used to generate droplets which are further used in patterning and organizing cells and other biologics in an outturn manner.
Laser-based Bio-printing In this bio-printing procedure laser energy is used in patterning of biologics and fabricating tissue constructs. This is one of the most advanced bioprinting because of its specific control on depositing biologics (genes, cells, growth factors, biomaterials, and drugs).[2]
Process of Bio-printing: Bio-printing is generally divided into three vital technological steps:
Pre-processing: It is the generation of tissue or organ drawing with help of CAD (computer-aided design) according to the real printing or manufacturing of the tissue or organ is done.
Processing: It is the process of actual printing done in a bio-printer, in this bio-printer the actual cells are stacked and encapsulated by a bio-construct.
Post-processing: As the final step the cells encapsulated in bio-construct in a special chamber known as ‘Bio-reactor’ that expedites maturation of organ, undergo the process of cell-proliferation, remodeling, and maturation.[2]
Section 2: Bio-Printing and Organ Transplantation
Current Trends of Organ Bio-printing: Currently 3D bio-printers are used for regenerative medicine in certain body tissues and organs, complete organ transplantation with a 3D bio-printer is still under a process that is being researched and experimented at an expeditious speed. Currently bio-printers pattern and deposit the primary cell types which are precisely similar to the mother tissue. The selection of the native cell plays a pivotal role in the functionality of the bio-printed tissue. When tissues are needed to be grown and proliferated into required cell types the Bio-ink of stem-cells is used in printing. [2][3]
Expected Organ Bio-printing: Rapidly advancing technologies in imaging and digital designing has aced the research on creating functional organs with bio-printing. Non-invasive imaging techniques like CAD-CAM (computer-aided designing and computer-aided manufacturing), MRI (magnetic resonance imaging), CT scan (computed tomography), and mathematical modeling gives minute details about the complex tissues and organs which can be used for designing and bio-printing the organs with help of advanced bio-printers like micro-extrusion, inkjet, and laser-assisted printing.[3]
Advantages of Organ Bioprinting: Organ transplant rejection is one of the worst fears and challenge by the host immune reaction. This challenge can be overcome by the use of autologous cells for 3D bio-printing. Autologous cells generally stem cells or can be pluripotent stem cells collected from biopsies. Autologous stem cells are the most reliable source, but these are of no use if a patient is already ill, because the stem cells are already infected and won’t give the required results, thus the stem cells are collected these days from the placenta that is preserved during childbirth. So the autologous bio-printing will reduce the chances of organ transplant rejection by almost 90%.[3]
The bio-printed organs and tissues will have a prolonged functionality with new advancements like self-renovation. Certain cells are difficult to isolate from the native tissue and difficult to cultures like cells from the heart, liver, and immune cells because of their short life-span. So with advanced bio-printing, these types of organs will also be bio-printed soon.[3]
Basically, bioprinting of organs from stem cells and pluripotent cells will increase the life-span of humans as a whole, while minimizing the chances of organ rejection and making bio-printing easy for the most complex of the organs.
Conclusion:
Bio-printing of organs and tissues that will be fully functional in every way possible will be the most ground-breaking and precious gift of science, innovation, and technology to the human race. The bioprinting of tissues and organs will not only be used for solid organ transplantation, but it will also innovatively change regenerative medicine and new drug discovery and formation.
Bio-printing will prolong the life span of the human race, with transplantation of new fully functional, self-healing organs. There will be no waiting list for the people in need of organ transplantation as the process of bio-printing will make the required organs with a full working capacity no matter how complex an organ or tissue structure is.
As the bio-printing is a recent concept in the field of regenerative medicine and a plethora of researches are going on, once the exceptionally good results come into existence it will change the whole view of life, whether will be organ transplants, new drug formation, and testing, this will reduce the time consumed in waiting and testing.
Drug formation and testing are generally are first tested on animals, so this animal testing makes it inter-species and thus to form and invent exact drug formulation is a time-consuming process, this bio-printing of tissues and organs of humans will make the drug formation and testing directly possible on actual human tissue which will tell the various drug reactions and changes needed to be done in the drug. This will eliminate animal testing and the discovery of new drugs will be quick.
Bio-printing of organs and tissues with cancerous growths and tumors will be helpful in the treatment plan of cancer or tumor. This will male the oncology treatments and cure at hand as various radiotherapies and chemo treatments can be practiced and tested first on the bio-printed organ with tumor or cancer and according to the results, treatment can be provided to the patient.
So the bioprinting of organs will disruptively in a positive way change the whole concept of medical sciences and with efficient and effective working newly bio-printed organs according to the patient need will give humans a second chance at life with a prolonged lifespan.
- Liu, F., Liu, C., Chen, Q., Ao, Q., Tian, X., Fan, J., … & Wang, X. (2018). Progress in organ 3D bioprinting. International Journal of Bioprinting, 4(1).
- Ozbolat, I. T. (2016). 3D bioprinting: fundamentals, principles, and applications. Academic Press.
- Charbe, N., McCarron, P. A., &Tambuwala, M. M. (2017). Three-dimensional bioprinting: a new frontier in oncology research. World journal of clinical oncology, 8(1), 21.
- https://www.organdonor.gov/statistics-stories/statistics.html
