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1 Stomach regeneration: Murine Tissue-Engineered Stomach Demonstrates Epithelial Differentiation 1) Speer et al. harvested neonatal stomach epithelial cells and seeded a polyglycolic acid (PGA) based porous scaffold. The seeded scaffold is implanted in adult mice for one week. Eventually cellularisation was evaluated using histology. Answer to the question in the table: What is the therapeutic product described above? What are the elements that identify such therapeutic product as a PTC? In what phase of the regulatory process for new PTCs can this PTC be localized? What are the standards that apply in this stage of the PTC process of development? What are the risks associated with this PTC (immunogenic, tumour, teratoma, infection, toxicity)? 2 Classify all the cell sources potentially usable in human patients for this therapy Cell source (based on immunogenic ity) Cell type/s Advantages Criticalities 3 2) The polyglycolic acid (PGA) is a scaffold with a porosity equal to 95%. It was cellularized with a cellular density of (0.019±0.007)* 106𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑚𝑚𝑚𝑚3. The scaffold could be modeled as a hollow cylinder with a height of 3mm (H=3mm), internal radius of 2.25mm ( RinC) and external radius of 4.25 mm ( RoutC). After the seeding and before the implantation, researchers had to store up the seeded scaffold in (V olmedium) 5ml standard medium, continuously stirred. How much time, the scaffold could be kept in the stirred medium without causing hypoxia? After calculations plot the oxygen concentration profile. Also consider these data: - V max (the worst case for oxygen consumption due to the maximum cell density Ni(max)); - c0 = 0.2 𝜇𝜇𝑚𝑚𝜇𝜇𝑐𝑐 𝑚𝑚𝑐𝑐 (initial concentration) - Km = 0.15 𝜇𝜇𝑚𝑚𝜇𝜇𝑐𝑐 𝑚𝑚𝑐𝑐 (constant saturation) - Cellular oxygen consumption: Vcell = 0.18 𝝁𝝁𝝁𝝁𝝁𝝁𝝁𝝁…