With the aid of tissue engineering, bladder reconstruction and repair has become a possibility. Tissue engineering is the combination of using biological and biocompatible materials in the goal of recreating functional tissues.1-6 To go into further detail we turn to a chart which shows the three basic components of tissue engineering. Here is a diagram shown as figure 2.
Figure 2: The three components of tissue engineering.6
Tissue engineering involves taking a scaffold made of a biocompatible material and seeding the appropriate cell types (in this case, bladder cells) onto the scaffold. By culturing the cells on the scaffold, the cells will be able to embed themselves into the biomaterial. In the case of Atala's work, a collagen-polyglycolic acid matrix was used to seed cells from the bladder submucosa.3 Polyglycolic acid (PGA), shown here in figure 3, is a biodegradable polymer which was shown to satisfy the requirements of a scaffold for tissue engineering.3 Initially, the patients were implanted with a cell-seeded scaffold which consisted of collagen-PGA, this was later revised to include a full omentum wrap which was shown to improve vascularization of the tissue.3 In all, 7 patients were used in Atala's landmark study.
Figure 3: PGA structure from http://www.courses.ahc.umn.edu/medical-school/BMEn/5001/notes/graphics/polyglycol.gif