Plants as Tissue Engineering Models
Plants are used in several fields including food processing, agriculture, pharmaceuticals, and medicine. Plant tissue culture is defined as the culture of plant seeds, tissues, cells, organs, explants, or protoplasts on nutrient media under controlled, sterile conditions. The advantages of using plants compared to animals for tissue engineering applications is that they are more abundant, sustainable, and cost efficient.
For several hundreds of years plants, have been studied in a variety of fields and used as tools for tissue engineering purposes.
- 1839 – Schleiden and Schwann proposed that the cell is basic unit of organisms 
- 1902 – Gottlieb Haberlandt developed the concept of in vitro cell culture
- 1904- Hannig cultured embryos from several cruciferous species 
- 1926 – Went discovered first plant growth hormone- Indole acetic acid 
- 1941 – Johannes Van Overbeek
- 1997 – Blattner et al. sequences E. colil genome
- 2005 – Rice genome sequenced under International Rise Genome Sequencing Project
Tissue Engineering Applications
The demand for organs has rapidly increased over the past years due to the lack of their availability. A major organ shortage has resulted with more than 100,000 patients waiting on the organ donor list . Major advances in organ development has increased the amount of viable options and solutions for tissue engineering organs. However, creating a vascular network within these organs still remains a major challenge. Vascular networks are required for the transport of nutrients and oxygen throughout the body.
Plant and animals exhibit similar vascular network structure. Furthermore, plant vasculature follows the same physiological law that describes the branching network design of the human cardiovascular system, known as Murray's law. Removal of cells of donor's tissue leaving a graft that would be non-immunogenic and retains the structure. An autologous graft Organs are then recellularized with patient's cells . Plant cell walls comprise of polysaccharides, in cellulose, pection, and hemicellulose. Cellulose is known to promote wound healing, while pectin has been studied for bone tissue engineering applications.
  Ott, H.C., Matthiesen, T.S., Goh, S.K., Black, L.D., Kren, S.M., Netoff, T.I., Taylor, D.A. (2008). Perfusion-decellularized matrix: using nature's platform to engineer a bioartificial heart. "Nature Medicine". 14(2): 213–221.