Tissue engineering is providing replacement alternatives that are being used in research today. For example, at the Université Laval in the Laboratoire d'organogénèse expérimentale (LOEX), scientists have created engineered tissue substitutes for:
- Vascular tissue
- Bronchial tissue
- Human cornea
- Human skin
Tissue engineered blood vessel generated from human cells. The vessel contains all three layers found in normal human blood vessels: the adventitia, the media and the endothelium. Courtesy of the FASEB Journal ® (L'Heureux N. et al. FASEB Journal 12(1): 47-56, 1998)
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Tissue engineered epidermis generated from human epidermal cells grown in culture. Courtesy of the LOEX®.
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These are being used in a variety of research areas in place of animals. For example:
- Tissue-engineered vascular substitutes are used to study the role of the adventitia layer of blood vessels in vascular physiology and related mechanisms. Using vascular substitutes allows researchers to avoid challenges related to obtaining healthy human vascular samples, and isolating intact adventitia.
Source: Auger F.A., D'Orléans P. and Germain L. (2007) Adventitia contribution to vascular contraction: hints provided by tissue-engineered substitutes. Cardiovascular Research 75(4):669-678.
- Bioengineered bronchial equivalents (BE) are prepared in vitro from bronchial epithelial (HBEC) and fibroblastic cells (HBFC) from biopsies of asthmatic and non-asthmatic human volunteers. The BE provide in vitro models to study the mechanisms involved in asthma.
Source: Paquette J.-S., Moulin V., Tremblay P., Bernier V., Boutet M., Laviolette M., Auger F.A., Boulet L.-P. and Goulet F. (2004) Tissue-engineered human asthmatic bronchial equivalents. European Cells and Materials 7:1-11.
- Tissue-engineered human cornea are used to study corneal wound healing
Source: Carrier P., Deschambeault A., Talbot M., Giasson C.J., Auger F.A., Guérin S.L. and Germain L. (2008) Characterization of wound reepithelialization using a new human tissue-engineered corneal wound healing model. Investigative Ophthalmology & Visual Science 49(4):1376-1385.
- Human vascular and skin substitutes are used to study the molecular mechanisms of transendothelial migration of human cancer cells through a human endothelium layer. Skin substitutes may provide more relevant information because they include cell surface molecules that are present in human cells but not animal cells.
Source: Tremblay P.L., Huot J. and Auger F.A. (2008) Mechanisms by which E-selectin regulates diapedesis of colon cancer cells under flow conditions. Cancer Research 68(13):5167-5176.