OBJECTIVETo investigate if recurrent autoimmunity explained hyperglycemia and C-peptide loss in three immunosuppressed simultaneous pancreas-kidney (SPK) transplant recipients.RESEARCH DESIGN AND METHODSWe monitored autoantibodies and autoreactive T-cells (using tetramers) and performed biopsy. The function of autoreactive T-cells was studied with in vitro and in vivo assays.RESULTSAutoantibodies were present pretransplant and persisted on follow-up in one patient. They appeared years after transplantation but before the development of hyperglycemia in the remaining patients. Pancreas transplant biopsies were taken within ∼1 year from hyperglycemia recurrence and revealed β-cell loss and insulitis. We studied autoreactive T-cells from the time of biopsy and repeatedly demonstrated their presence on further follow-up, together with autoantibodies. Treatment with T-cell–directed therapies (thymoglobulin and daclizumab, all patients), alone or with the addition of B-cell–directed therapy (rituximab, two patients), nonspecifically depleted T-cells and was associated with C-peptide secretion for >1 year. Autoreactive T-cells with the same autoantigen specificity and conserved T-cell receptor later reappeared with further C-peptide loss over the next 2 years. Purified autoreactive CD4 T-cells from two patients were cotransplanted with HLA-mismatched human islets into immunodeficient mice. Grafts showed β-cell loss in mice receiving autoreactive T-cells but not control T-cells.CONCLUSIONSWe demonstrate the cardinal features of recurrent autoimmunity in three such patients, including the reappearance of CD4 T-cells capable of mediating β-cell destruction. Markers of autoimmunity can help diagnose this underappreciated cause of graft loss. Immune monitoring during therapy showed that autoimmunity was not resolved by the immunosuppressive agents used.

for the Wireless Innovation for Seniors With Diabetes Mellitus (WISDM) Study Group IMPORTANCE Continuous glucose monitoring (CGM) provides real-time assessment of glucose levels and may be beneficial in reducing hypoglycemia in older adults with type 1 diabetes. OBJECTIVE To determine whether CGM is effective in reducing hypoglycemia compared with standard blood glucose monitoring (BGM) in older adults with type 1 diabetes. DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial conducted at 22 endocrinology practices in the United States among 203 adults at least 60 years of age with type 1 diabetes. INTERVENTIONS Participants were randomly assigned in a 1:1 ratio to use CGM (n = 103) or standard BGM (n = 100). MAIN OUTCOMES AND MEASURESThe primary outcome was CGM-measured percentage of time that sensor glucose values were less than 70 mg/dL during 6 months of follow-up. There were 31 prespecified secondary outcomes, including additional CGM metrics for hypoglycemia, hyperglycemia, and glucose control; hemoglobin A 1c (HbA 1c ); and cognition and patient-reported outcomes, with adjustment for multiple comparisons to control for false-discovery rate. RESULTSOf the 203 participants (median age, 68 [interquartile range {IQR}, 65-71] years; median type 1 diabetes duration, 36 [IQR, years; 52% female; 53% insulin pump use; mean HbA 1c , 7.5% [SD, 0.9%]), 83% used CGM at least 6 days per week during month 6. Median time with glucose levels less than 70 mg/dL was 5.1% (73 minutes per day) at baseline and 2.7% (39 minutes per day) during follow-up in the CGM group vs 4.7% (68 minutes per day) and 4.9% (70 minutes per day), respectively, in the standard BGM group (adjusted treatment difference, −1.9% (−27 minutes per day); 95% CI, −2.8% to −1.1% [−40 to −16 minutes per day]; P <.001). Of the 31 prespecified secondary end points, there were statistically significant differences for all 9 CGM metrics, 6 of 7 HbA 1c outcomes, and none of the 15 cognitive and patient-reported outcomes. Mean HbA 1c decreased in the CGM group compared with the standard BGM group (adjusted group difference, −0.3%; 95% CI, −0.4% to −0.1%; P <.001). The most commonly reported adverse events using CGM and standard BGM, respectively, were severe hypoglycemia (1 and 10), fractures (5 and 1), falls (4 and 3), and emergency department visits (6 and 8).CONCLUSIONS AND RELEVANCE Among adults aged 60 years or older with type 1 diabetes, continuous glucose monitoring compared with standard blood glucose monitoring resulted in a small but statistically significant improvement in hypoglycemia over 6 months. Further research is needed to understand the long-term clinical benefit.

Low-dose interleukin-2 (IL-2) inhibited unwanted immune responses in several clinical settings and is currently being tested in patients with type 1 diabetes (T1D). Low-dose IL-2 selectively targets regulatory T cells (Tregs), but the mechanisms underlying this selectivity are poorly understood. We show that IL-2–dependent STAT5 activation in Tregs from healthy individuals and patients with T1D occurred at an ∼10-fold lower concentration of IL-2 than that required by T memory (TM) cells or by in vitro–activated T cells. This selective Treg responsiveness is explained by their higher expression of IL-2 receptor subunit α (IL-2Rα) and γ chain and also endogenous serine/threonine phosphatase protein phosphates 1 and/or 2A activity. Genome-wide profiling identified an IL-2–dependent transcriptome in human Tregs. Quantitative assessment of selected targets indicated that most were optimally activated by a 100-fold lower concentration of IL-2 in Tregs versus CD4+ TM cells. Two such targets were selectively increased in Tregs from T1D patients undergoing low-dose IL-2 therapy. Thus, human Tregs possess an IL-2–dependent transcriptional amplification mechanism that widens their selective responses to low IL-2. Our findings support a model where low-dose IL-2 selectively activates Tregs to broadly induce their IL-2/IL-2R gene program and provide a molecular underpinning for low-dose IL-2 therapy to enhance Tregs for immune tolerance in T1D.

No abstract

No abstract

Context Use of continuous glucose monitoring (CGM) is increasing for insulin-requiring patients with diabetes. Although data on glycemic profiles of healthy, nondiabetic individuals exist for older sensors, assessment of glycemic metrics with new-generation CGM devices is lacking. Objective To establish reference sensor glucose ranges in healthy, nondiabetic individuals across different age groups using a current generation CGM sensor. Design Multicenter, prospective study. Setting Twelve centers within the T1D Exchange Clinic Network. Patients or Participants Nonpregnant, healthy, nondiabetic children and adults (age ≥6 years) with nonobese body mass index. Intervention Each participant wore a blinded Dexcom G6 CGM, with once-daily calibration, for up to 10 days. Main Outcome Measures CGM metrics of mean glucose, hyperglycemia, hypoglycemia, and glycemic variability. Results A total of 153 participants (age 7 to 80 years) were included in the analyses. Mean average glucose was 98 to 99 mg/dL (5.4 to 5.5 mmol/L) for all age groups except those over 60 years, in whom mean average glucose was 104 mg/dL (5.8 mmol/L). The median time between 70 to 140 mg/dL (3.9 to 7.8 mmol/L) was 96% (interquartile range, 93 to 98). Mean within-individual coefficient of variation was 17 ± 3%. Median time spent with glucose levels &gt;140 mg/dL was 2.1% (30 min/d), and median time spent with glucose levels &lt;70 mg/dL (3.9 mmol/L) was 1.1% (15 min/d). Conclusion By assessing across age groups in a healthy, nondiabetic population, normative sensor glucose data have been derived and will be useful as a benchmark for future research studies.

No abstract

Background: We describe the utilization of telemedicine visits (video or telephone) across the T1D Exchange Quality Improvement Collaborative (T1DX-QI) during the COVID-19 pandemic. Metrics, site-level survey results, and examples of interventions conducted to support telemedicine in type 1 diabetes (T1D) are shown. Methods: Thirteen clinics (11 pediatric, 2 adult) provided monthly telemedicine metrics between December 2019-August 2020 and 21 clinics completed a survey about their telemedicine practices. Results:The proportion of telemedicine visits in T1DX-QI before the pandemic was less than 1%, rising to an average of 95.2% in April 2020 (range 52.3% to 99.5). Three sites initially used mostly telephone visits before converting to video visits. By August 2020, the proportion of telemedicine visits decreased to an average of 45% across T1DX-QI (range 10% to 86.6%).The majority of clinics (62%) performed both video and telephone visits; Zoom was the most popular video platform used. Over 95% of clinics reported using CareLink™, Clarity®, Glooko™ and/or t:connect® to view device data, with only one center reporting automated data upload into the electronic medical record. The majority of centers had multidisciplinary teams participating in the video visits. All sites reported reimbursement for video visits, and 95% of sites reported coverage for telephone visits early on in the pandemic. Conclusions:There was rapid adoption of telemedicine in T1DX-QI during the COVID-19 pandemic. Future insurance reimbursement for telemedicine visits and the ideal ratio of telemedicine to in-person visits in T1D care remain to be determined.