Patient description: The patient is a 24-year-old man who has had type 1 diabetes for 11 years. He presents to the emergency room with hyperglycemia and concern for possible diabetic ketoacidosis after not taking his insulin for 3 days. The patient reports that he is currently homeless and has lost his supply of insulin, syringes, glucometer, and glucose testing supplies. The patient states that at the time of his initial diagnosis with type 1 diabetes he was hospitalized with a glucose value >1000 mg/dL. At the time, he was experiencing polyuria, polydipsia, and polyphagia. He reports that he has been on insulin since the time of his diagnosis, and he has never been prescribed oral agents for diabetes management. Most recently, he has been using insulin glargine 55 units once daily, and insulin aspart sliding scale 3 times daily. The patient has had previous episodes of diabetic ketoacidosis, for which he was hospitalized. With this episode of hyperglycemia, he is not experiencing any nausea, vomiting, or abdominal discomfort, and he appears well. His lab studies showed: A1c: 11.3% Creatinine: 0.9 mg/dL with eGFR >60 mL/min Aspartate aminotransferase (AST): 17 U/L Alanine aminotransferase (ALT): 14 U/L Beta-hydroxybutyrate: 0.1 mmol/L Bicarbonate: 25 mEq/L Anion

Clinical trial eligibility criteria: eligible ages (years): 18.0-65.0,  Type 1 Diabetes Mellitus Potential candidates must have type 1 diabetes mellitus and fulfill one or more of the following: 1. Manifest signs and symptoms that are severe enough to be incapacitating. Incapacitating signs and symptoms hypoglycemic episodes requiring assistance by others and hypoglycemia unawareness (the inability to recognize low blood glucoses; glucoses < 54 mg/dl). These patients are at high risk for involvement in accidents (they can lose consciousness or act irrationally), thus causing harm to themselves and/or others. 2. Patients with poor diabetes control (HbA1c > 8.0% but < 12%), despite intensive insulin therapy, as defined by: self monitoring of blood glucose ≥ 4 times/day, multiple insulin injections (≥ 3/day) or insulin pump, and close monitoring of blood glucose control by an endocrinologist. These patients can experience acute, rapid hyperglycemia secondary to several stress factors, that can lead to dehydration, disorientation, and in some instances, ketoacidosis. 3. Progressive diabetic complications. These patients with chronically poor glycemic control are at higher risk for the development of a wide variety of complications (retinopathy, neuropathy, nephropathy, and cardiovascular disease) associated with diabetes  Potential candidates will be excluded as per the following 1. Age < 18 or > 65 years 2. Duration of diabetes < 5 years 3. Do not have a physician that is monitoring diabetes for > 6 months 4. Body mass index > 26 5. Weight > 80 kg 6. Insulin requirement > 1.0 u/kg/d 7. HbA1c > 12% 8. Stimulated or basal C-peptide > 0.3 ng/ml 9. Corrected creatinine clearance < 60 ml/min 10. Serum creatinine consistently above 1.6 mg/dl 11. Macroalbuminuria (> 300 mg/24 hours) 12. Anemia (hemoglobin < 12.0 g/dl for males; < 11 g/dl for females) 13. Hyperlipidemia (fasting low-density lipoprotein [LDL] cholesterol > 130 mg/dl and/or fasting triglycerides > 200 mg/dl) 14. Abnormal liver function tests (consistently > 1.5 x normal range) 15. Serological evidence of HIV, HBsAg and/or HBcAb, HBsAb without history of vaccination, human t cell lymphotropic virus 1 (HTLV-1), or hepatitis C virus (HCV) 16. Negative serology for Epstein-Barr virus (EBV) or evidence of acute or chronic infection (IgM ≥ IgG) 17. Lack of updated immunizations per current Centers for Disease Control (CDC) guidelines (including lack of immunization against hepatitis B, pneumococcus and influenza - during season) 18. Presence of panel reactive antibodies > 20% 19. Prostate-specific antigen (PSA) > 4 ng/ml unless malignancy is ruled out 20. Positive tuberculin test (unless proof of adequate treatment for latent tuberculosis can be provided) 21. X-ray evidence of pulmonary infection or other significant pathology 22. Gall stones and/or portal hypertension and/or hemangioma on liver ultrasound 23. Abnormal abdominal or pelvic ultrasound (evidence of masses that are considered suspicious for malignancy or adenopathy) 24. Active peptic ulcer disease 25. Active infections 26. Unstable cardiovascular status (including positive stress echocardiography if age > 35) 27. Untreated or unstable proliferative diabetic retinopathy 28. Previous/concurrent organ transplantation (except for failed islet cell or pancreas transplantation) 29. Malignancy or previous malignancy 30. Any medical condition requiring chronic use of steroids 31. Active alcohol or substance abuse; smoking in the last 6 months. 32. Sexually active females who are not post-menopausal surgically sterile, or not using an acceptable method of contraception (oral contraceptives, Norplant, Depo-Provera, and barrier devices with spermicide are acceptable; condoms used alone are not acceptable) 33. Positive pregnancy test or intent for future pregnancy, or male subject's intent to procreate 34. Any condition or any circumstances that make it unsafe to undergo an islet cell transplant 35. Psychogenically unable to comply 36. Failed psychological evaluation 37. Persistent leukopenia (white blood cell count < 3,000/uL on more than 3 occasions)