METHODS: This research is articulated in three distinct protocols. All subjects will be on an isocaloric, maze and cane sugar free diet for one week before study. All T1DM patients will be on CGM/CSII and will be recruited from the patient population attending our Outpatient Insulin Pump Therapy Clinic. Each patient will continue to use his/her own pump device, insulin analogue and glucose sensor. All studies will start at 07:00 AM after an overnight fast (≥ 10 hours). All blood samples will be collected in refrigerated tubes and promptly spun at 1500 g; plasma will be separated and stored at -80° C. According to the planned use of plasma, tubes for blood samples will contain ethylenediaminetetraacetic acid (EDTA) for anticoagulation±antiglicolytic agent±serine protease and DPP4 inhibitors.