Case Study – Diabetes Mellitus Mohinder, a 28 year old male, hadbeen diagnosed with diabetes mellitus when he was 12 years old. Hestarted experiencing polydipsia, polyuria and polyphagia and hisparents noticed that he was very lethargic and seemed continuouslyfatigued. They would occasionally detect the sweet, “fruity” smellof acetone on his breath. Their PA informed them that this was asign of ketoacidosis associated with the diabetes. At the time,high fasting glucose levels and islet cell antibodies (ICA) hadbeen detected in his blood. His doctors had him carry out a regimento control his fluctuations in blood glucose which included diet,exercise and administration of exogenous insulin. At first he wasadministering insulin 1-3 times a day as indicated by measuring theglucose concentrations in small blood samples obtained frompricking his finger. When he was 22, he got a small battery-poweredinfusion pump that continuously infused insulin subcutaneously. Nowhe is considering an experimental treatment that involvesimplantation of beta-cells derived from donated pancreases. Thesecells implant in the liver and produce insulin in response to bloodglucose levels.

3. What do the ICA suggest about the etiology of hiscondition?

4. Why is an insulin infusion pump superior to periodic insulininjections? Why would donated beta-cells be superior to theinfusion pump if they can be successfully implanted? (Think aboutthe negative feedback loops for control of blood glucose as youanswer this question. How do the concepts of sensitivity, gain andlag time relate to this question?)

5. What are the drawbacks to donated pancreas cells? How mightembryonic stem cells be used to avoid these problems?