RFX6 Maintains Gene Expression and Function of Adult Human Islet α-Cells.

Mutations in the gene encoding the transcription factor regulatory factor X-box binding 6 (RFX6) are associated with human diabetes. Within pancreatic islets, RFX6 expression is most abundant in islet α-cells, and α-cell RFX6 expression is altered in diabetes. However, the roles of RFX6 in regulating gene expression, glucagon output, and other crucial human adult α-cell functions are not yet understood. We developed a method for selective genetic targeting of human α-cells and assessed RFX6-dependent α-cell function. RFX6 suppression with RNA interference led to impaired α-cell exocytosis and dysregulated glucagon secretion in vitro and in vivo. By contrast, these phenotypes were not observed with RFX6 suppression across all islet cells. Transcriptomics in α-cells revealed RFX6-dependent expression of genes governing nutrient sensing, hormone processing, and secretion, with some of these exclusively expressed in human α-cells. Mapping of RFX6 DNA-binding sites in primary human islet cells identified a subset of direct RFX6 target genes. Together, these data unveil RFX6-dependent genetic targets and mechanisms crucial for regulating adult human α-cell function.

HNF1α maintains pancreatic α and ß cell functions in primary human islets.

HNF1A haploinsufficiency underlies the most common form of human monogenic diabetes (HNF1A-maturity onset diabetes of the young [HNF1A-MODY]), and hypomorphic HNF1A variants confer type 2 diabetes risk. But a lack of experimental systems for interrogating mature human islets has limited our understanding of how the transcription factor HNF1α regulates adult islet function. Here, we combined conditional genetic targeting in human islet cells, RNA-Seq, chromatin mapping with cleavage under targets and release using nuclease (CUT&RUN), and transplantation-based assays to determine HNF1α-regulated mechanisms in adult human pancreatic α and ß cells. Short hairpin RNA-mediated (shRNA-mediated) suppression of HNF1A in primary human pseudoislets led to blunted insulin output and dysregulated glucagon secretion after transplantation in mice, recapitulating phenotypes observed in patients with diabetes. These deficits corresponded with altered expression of genes encoding factors critical for hormone secretion, including calcium channel subunits, ATPase transporters, and extracellular matrix constituents. Additionally, HNF1A loss led to upregulation of transcriptional repressors, providing evidence for a mechanism of transcriptional derepression through HNF1α. CUT&RUN mapping of HNF1α DNA binding sites in primary human islets imputed a subset of HNF1α-regulated genes as direct targets. These data elucidate mechanistic links between HNF1A loss and diabetic phenotypes in mature human α and ß cells.

Curative islet and hematopoietic cell transplantation in diabetic mice without toxic bone marrow conditioning.

Mixed hematopoietic chimerism can promote immune tolerance of donor-matched transplanted tissues, like pancreatic islets. However, adoption of this strategy is limited by the toxicity of standard treatments that enable donor hematopoietic cell engraftment. Here, we address these concerns with a non-myeloablative conditioning regimen that enables hematopoietic chimerism and allograft tolerance across fully mismatched major histocompatibility complex (MHC) barriers. Treatment with an αCD117 antibody, targeting c-Kit, administered with T cell-depleting antibodies and low-dose radiation permits durable multi-lineage chimerism in immunocompetent mice following hematopoietic cell transplant. In diabetic mice, co-transplantation of donor-matched islets and hematopoietic cells durably corrects diabetes without chronic immunosuppression and no appreciable evidence of graft-versus-host disease (GVHD). Donor-derived thymic antigen-presenting cells and host-derived peripheral regulatory T cells are likely mediators of allotolerance. These findings provide the foundation for safer bone marrow conditioning and cell transplantation regimens to establish hematopoietic chimerism and islet allograft tolerance.

Intoxication and pitch control in tonal and non-tonal language speakers.

Alcohol intoxication is known to affect pitch variability in non-tonal languages. In this study, intoxication's effects on pitch were examined in tonal and non-tonal language speakers, in both their native language (L1; German, Korean, Mandarin) and nonnative language (L2; English). Intoxication significantly increased pitch variability in the German group (in L1 and L2), but not in the Korean or Mandarin groups (in L1 or L2), although there were individual differences. These results support the view that pitch control is related to the functional load of pitch and is an aspect of speech production that can be advantageously transferred across languages, overriding the expected effects of alcohol.

Islet cell replacement and transplantation immunology in a mouse strain with inducible diabetes.

Improved models of experimental diabetes are needed to develop cell therapies for diabetes. Here, we introduce the B6 RIP-DTR mouse, a model of experimental diabetes in fully immunocompetent animals. These inbred mice harbor the H2b major histocompatibility complex (MHC), selectively express high affinity human diphtheria toxin receptor (DTR) in islet ß-cells, and are homozygous for the Ptprca (CD45.1) allele rather than wild-type Ptprcb (CD45.2). 100% of B6 RIP-DTR mice rapidly became diabetic after a single dose of diphtheria toxin, and this was reversed indefinitely after transplantation with islets from congenic C57BL/6 mice. By contrast, MHC-mismatched islets were rapidly rejected, and this allotransplant response was readily monitored via blood glucose and graft histology. In peripheral blood of B6 RIP-DTR with mixed hematopoietic chimerism, CD45.2 BALB/c donor blood immune cells were readily distinguished from host CD45.1 cells by flow cytometry. Reliable diabetes induction and other properties in B6 RIP-DTR mice provide an important new tool to advance transplant-based studies of islet replacement and immunomodulation to treat diabetes.

The Tabula Sapiens: A multiple-organ, single-cell transcriptomic atlas of humans.

Molecular characterization of cell types using single-cell transcriptome sequencing is revolutionizing cell biology and enabling new insights into the physiology of human organs. We created a human reference atlas comprising nearly 500,000 cells from 24 different tissues and organs, many from the same donor. This atlas enabled molecular characterization of more than 400 cell types, their distribution across tissues, and tissue-specific variation in gene expression. Using multiple tissues from a single donor enabled identification of the clonal distribution of T cells between tissues, identification of the tissue-specific mutation rate in B cells, and analysis of the cell cycle state and proliferative potential of shared cell types across tissues. Cell type-specific RNA splicing was discovered and analyzed across tissues within an individual.

ZIP Code-Level Estimation of Air Quality and Health Risk Due to Particulate Matter Pollution in New York City.

Exposure to PM2.5 is associated with hundreds of premature mortalities every year in New York City (NYC). Current air quality and health impact assessment tools provide county-wide estimates but are inadequate for assessing health benefits at neighborhood scales, especially for evaluating policy options related to energy efficiency or climate goals. We developed a new ZIP Code-Level Air Pollution Policy Assessment (ZAPPA) tool for NYC by integrating two reduced form models─Community Air Quality Tools (C-TOOLS) and the Co-Benefits Risk Assessment Health Impacts Screening and Mapping Tool (COBRA)─that propagate emissions changes to estimate air pollution exposures and health benefits. ZAPPA leverages custom higher resolution inputs for emissions, health incidences, and population. It, then, enables rapid policy evaluation with localized ZIP code tabulation area (ZCTA)-level analysis of potential health and monetary benefits stemming from air quality management decisions. We evaluated the modeled 2016 PM2.5 values against observed values at EPA and NYCCAS monitors, finding good model performance (FAC2, 1; NMSE, 0.05). We, then, applied ZAPPA to assess PM2.5 reduction-related health benefits from five illustrative policy scenarios in NYC focused on (1) commercial cooking, (2) residential and commercial building fuel regulations, (3) fleet electrification, (4) congestion pricing in Manhattan, and (5) these four combined as a "citywide sustainable policy implementation" scenario. The citywide scenario estimates an average reduction in PM2.5 of 0.9 µg/m3. This change translates to avoiding 210-475 deaths, 340 asthma emergency department visits, and monetized health benefits worth $2B to $5B annually, with significant variation across NYC's 192 ZCTAs. ZCTA-level assessments can help prioritize interventions in neighborhoods that would see the most health benefits from air pollution reduction. ZAPPA can provide quantitative insights on health and monetary benefits for future sustainability policy development in NYC.

Cultural factors weaken but do not reverse left-to-right spatial biases in numerosity processing: Data from Arabic and English monoliterates and Arabic-English biliterates.

Directional response biases due to a conceptual link between space and number, such as a left-to-right hand bias for increasing numerical magnitude, are known as the SNARC (Spatial-Numerical Association of Response Codes) effect. We investigated how the SNARC effect for numerosities would be influenced by reading-writing direction, task instructions, and ambient visual environment in four literate populations exemplifying opposite reading-writing cultures-namely, Arabic (right-to-left script) and English (left-to-right script). Monoliterates and biliterates in Jordan and the U.S. completed a speeded numerosity comparison task to assess the directionality and magnitude of a SNARC effect in their numerosity processing. Monoliterates' results replicated previously documented effects of reading-writing direction and task instructions: the SNARC effect found in left-to-right readers was weakened in right-to-left readers, and the left-to-right group exhibited a task-dependency effect (SNARC effect in the smaller condition, reverse SNARC effect in the larger condition). Biliterates' results did not show a clear effect of environment; instead, both biliterate groups resembled English monoliterates in showing a left-to-right, task-dependent SNARC effect, albeit weaker than English monoliterates'. The absence of significant biases in all Arabic-reading groups (biliterates and Arabic monoliterates) points to a potential conflict between distinct spatial-numerical mapping codes. This view is explained in terms of the proposed Multiple Competing Codes Theory (MCCT), which posits three distinct spatial-numerical mapping codes (innate, cardinal, ordinal) during numerical processing-each involved at varying levels depending on individual and task factors.

SARS-CoV-2 infects human pancreatic ß cells and elicits ß cell impairment.

Emerging evidence points toward an intricate relationship between the pandemic of coronavirus disease 2019 (COVID-19) and diabetes. While preexisting diabetes is associated with severe COVID-19, it is unclear whether COVID-19 severity is a cause or consequence of diabetes. To mechanistically link COVID-19 to diabetes, we tested whether insulin-producing pancreatic ß cells can be infected by SARS-CoV-2 and cause ß cell depletion. We found that the SARS-CoV-2 receptor, ACE2, and related entry factors (TMPRSS2, NRP1, and TRFC) are expressed in ß cells, with selectively high expression of NRP1. We discovered that SARS-CoV-2 infects human pancreatic ß cells in patients who succumbed to COVID-19 and selectively infects human islet ß cells in vitro. We demonstrated that SARS-CoV-2 infection attenuates pancreatic insulin levels and secretion and induces ß cell apoptosis, each rescued by NRP1 inhibition. Phosphoproteomic pathway analysis of infected islets indicates apoptotic ß cell signaling, similar to that observed in type 1 diabetes (T1D). In summary, our study shows SARS-CoV-2 can directly induce ß cell killing.

Standing by: The spatial organization of coercive institutions in China.

How do authoritarian states organize their coercive institutions over space? We argue that autocrats maximize the utility of their limited coercive resources by clustering them with perceived threats in society, i.e., segments of the population that are ideologically distant and have mobilizational potential. We test this proposition using a dataset that covers the universe of police stations (N = 147,428) and religious sites (N = 115,394) in China. We find that police stations are more likely to be located within walking distance of foreign religious sites (churches) than other sites (temples), even after controlling for the estimated population within 1 km of each site and a set of key site attributes. This finding is robust to using alternative model specifications, different variable measurements, and multiple data sources. Moving beyond the clustering pattern, we also address the temporal order issue and show that the Chinese state has allocated more new coercive resources around existing foreign religious sites than native sites, i.e., after these sites are already in place. This study enriches our understanding of how autocrats rule and further opens up an emerging new methodological avenue for research on authoritarian politics.

Collaboration between Law Enforcement Agencies in Combating Cybercrime: Implications of a Taiwanese Case Study about ATM Hacking.

An increasing number of cybercrimes has presented new global challenges to law enforcement agencies that traditionally operate within designated geographical jurisdictions and patrol territories. The borderless nature of cyberspace has brought substantial opportunities-both legal and illegal-to its users, and many local law enforcement agencies have encountered motivated offenders taking advantage of the globally connected Internet and causing damage locally and transnationally. This study examines a high-profile case of European criminals who hacked into a Taiwanese financial institution-First Commercial Bank (FCB)-and programmed its ATMs to "spit out" cash netting the thieves $2.6 million US dollars in 2016 summer. Before the incident of FCB, this European criminal group committed more than a hundred similar ATMs hackings, victimizing dozens of financial institutions across several European countries, and profiting over one billion Euros. FCB is the only case revealing specific details about the modus operandi of ATM hacking thus far, in addition to disclosing reactions from law enforcement. By analyzing qualitative data collected from different branches of law enforcement involved in the investigations, this unique case study underscores the importance of national-local law enforcement collaboration in fighting transnational cybercrime. Empirical implications are particularly valuable in the law enforcement context of "turf jealousies" when defending homeland security.

In vivo studies of glucagon secretion by human islets transplanted in mice.

Little is known about regulated glucagon secretion by human islet α-cells compared to insulin secretion from ß-cells, despite conclusive evidence of dysfunction in both cell types in diabetes mellitus. Distinct insulins in humans and mice permit in vivo studies of human ß-cell regulation after human islet transplantation in immunocompromised mice, whereas identical glucagon sequences prevent analogous in vivo measures of glucagon output from human α-cells. Here, we use CRISPR-Cas9 editing to remove glucagon codons 2-29 in immunocompromised NSG mice, preserving the production of other proglucagon-derived hormones. Glucagon knockout NSG (GKO-NSG) mice have metabolic, liver and pancreatic phenotypes associated with glucagon-signalling deficits that revert after transplantation of human islets from non-diabetic donors. Glucagon hypersecretion by transplanted islets from donors with type 2 diabetes revealed islet-intrinsic defects. We suggest that GKO-NSG mice provide an unprecedented resource to investigate human α-cell regulation in vivo.

Molecular and genetic regulation of pig pancreatic islet cell development.

Reliance on rodents for understanding pancreatic genetics, development and islet function could limit progress in developing interventions for human diseases such as diabetes mellitus. Similarities of pancreas morphology and function suggest that porcine and human pancreas developmental biology may have useful homologies. However, little is known about pig pancreas development. To fill this knowledge gap, we investigated fetal and neonatal pig pancreas at multiple, crucial developmental stages using modern experimental approaches. Purification of islet ß-, α- and δ-cells followed by transcriptome analysis (RNA-seq) and immunohistology identified cell- and stage-specific regulation, and revealed that pig and human islet cells share characteristic features that are not observed in mice. Morphometric analysis also revealed endocrine cell allocation and architectural similarities between pig and human islets. Our analysis unveiled scores of signaling pathways linked to native islet ß-cell functional maturation, including evidence of fetal α-cell GLP-1 production and signaling to ß-cells. Thus, the findings and resources detailed here show how pig pancreatic islet studies complement other systems for understanding the developmental programs that generate functional islet cells, and that are relevant to human pancreatic diseases.

A Modern Comparison of Urodynamic Findings in Diabetic Versus Nondiabetic Women.

OBJECTIVES: Few contemporary studies exist regarding urodynamic (UDS) findings in patients with diabetes mellitus (DM), and data are conflicting. Our aim was to compare UDS findings in women with and without DM. METHODS: Data from female patients in a prospectively maintained UDS database (2010-2014) were reviewed. Studies were performed according to International Continence Society standards. Clinical data, presenting symptoms, and UDS findings were compared in women with and without DM, controlling for demographic and pertinent variables. RESULTS: There were 384 patients who met the inclusion criteria, of whom 88 (26%) had DM. Symptoms at presentation were not statistically different in women with and without DM. Women with DM had larger bladder capacity (mean, 493 mL vs 409 mL; P = 0.005) and had more detrusor underactivity (30% vs 18%, P = 0.042) when compared with nondiabetic women. Diabetic women were more frequently diagnosed as having impaired sensation, or lack of desire to void, at 75% of capacity (17% vs 5%, P = 0.001). In women with diabetes, a serum hemoglobin A1c level of at least 7.5% was associated with delayed first sensation and first urge. Diagnosis of DM of more than 10 years was associated with greater volume at first urge, and maximal capacity, lower detrusor pressures, and higher postvoid residual. CONCLUSIONS: In this contemporary series, women with DM demonstrated similar presenting complaints to women without DM but had significantly altered UDS findings. Among diabetic female patients, diabetes control and duration of diabetes seem to impact bladder sensation and contractility. Urodynamics may be helpful in diabetic female patients to diagnose underlying concealed bladder dysfunction before initiation of treatment.

Architecture of the Short External Rotator Muscles of the Hip.

BACKGROUND: Muscle architecture, or the arrangement of sarcomeres and fibers within muscles, defines functional capacity. There are limited data that provide an understanding of hip short external rotator muscle architecture. The purpose of this study was thus to characterize the architecture of these small hip muscles. METHODS: Eight muscles from 10 independent human cadaver hips were used in this study (n = 80 muscles). Architectural measurements were made on pectineus, piriformis, gemelli, obturators, quadratus femoris, and gluteus minimus. Muscle mass, fiber length, sarcomere length, and pennation angle were used to calculate the normalized muscle fiber length, which defines excursion, and physiological cross-sectional area (PCSA), which defines force-producing capacity. RESULTS: Gluteus minimus had the largest PCSA (8.29 cm2) followed by obturator externus (4.54 cm2), whereas superior gemellus had the smallest PCSA (0.68 cm2). Fiber lengths clustered into long (pectineus - 10.38 cm and gluteus minimus - 10.30 cm), moderate (obturator internus - 8.77 cm and externus - 8.04 cm), or short (inferior gemellus - 5.64 and superior gemellus - 4.85). There were no significant differences among muscles in pennation angle which were all nearly zero. When the gemelli and obturators were considered as a single functional unit, their collective PCSA (10.00 cm2) exceeded that of gluteus minimus as a substantial force-producing group. CONCLUSIONS: The key findings are that these muscles have relatively small individual PCSAs, short fiber lengths, and low pennation angles. The large collective PCSA and short fiber lengths of the gemelli and obturators suggest that they primarily play a stabilizing role rather than a joint rotating role.

Perception of nonnative tonal contrasts by Mandarin-English and English-Mandarin sequential bilinguals.

This study examined the role of acquisition order and crosslinguistic similarity in influencing transfer at the initial stage of perceptually acquiring a tonal third language (L3). Perception of tones in Yoruba and Thai was tested in adult sequential bilinguals representing three different first (L1) and second language (L2) backgrounds: L1 Mandarin-L2 English (MEBs), L1 English-L2 Mandarin (EMBs), and L1 English-L2 intonational/non-tonal (EIBs). MEBs outperformed EMBs and EIBs in discriminating L3 tonal contrasts in both languages, while EMBs showed a small advantage over EIBs on Yoruba. All groups showed better overall discrimination in Thai than Yoruba, but group differences were more robust in Yoruba. MEBs' and EMBs' poor discrimination of certain L3 contrasts was further reflected in the L3 tones being perceived as similar to the same Mandarin tone; however, EIBs, with no knowledge of Mandarin, showed many of the same similarity judgments. These findings thus suggest that L1 tonal experience has a particularly facilitative effect in L3 tone perception, but there is also a facilitative effect of L2 tonal experience. Further, crosslinguistic perceptual similarity between L1/L2 and L3 tones, as well as acoustic similarity between different L3 tones, play a significant role at this early stage of L3 tone acquisition.

Comparison of lateral lumbar interbody fusion (LLIF) with open versus percutaneous screw fixation for adult degenerative scoliosis.

STUDY DESIGN: Retrospective Review. OBJECTIVES: Compare clinical outcomes and radiographic correction of adult degenerative scoliosis (ADS) patients treated with lateral lumbar interbody fusion (LLIF), combined either with percutaneous (no laminectomy) versus open laminectomy/pedicle screw instrumentation. METHODS: Twenty-two ADS patients undergoing combined LLIF and posterior instrumentation were divided into two groups: thirteen patients underwent LLIF with open laminectomy and posterior pedicle instrumentation (Group-1, six revision); nine patients underwent LLIF with percutaneous pedicle instrumentation (no decompression) (Group-2). Radiographs, CT/MRI, peri-operative complications, VAS, SF-12, and ODI were measured. RESULTS: Average follow up was 22 months. In Group-1 and Group-2, respectively: Mean coronal Cobb angle corrected 12.6° and 5.8°; Mean regional lumbar lordosis improved 11.1° and 3.8°; Pelvic incidence minus lumbar lordosis mismatch corrected to within +/-9° in 46% and 0% of patients; Mean VAS improved from 5.4 to 2.8 and 6.3 to 1; Mean ODI improved 19% and 22%. Improvements were found in SF-12 PCS and MCS scores. CONCLUSIONS: Both open and percutaneous posterior techniques following LLIF significantly improved clinical outcomes. Open procedures resulted in significantly better radiographic improvements but also higher complication rates. LLIF with percutaneous posterior fixation, without decompression, should be considered part of the algorithm in select ADS patients with remaining compensatory mechanisms and understanding that greater degrees of correction may require an open, more extensive approach.

Early TLR4 Blockade Attenuates Sterile Inflammation-mediated Stress in Islets During Isolation and Promotes Successful Transplant Outcomes.

BACKGROUND: During the isolation process, pancreatic islets are exposed to an environment of sterile inflammation resulting in an upregulated inflammatory state before transplantation. Toll-like receptor 4 (TLR4) has been identified as a major mediator of sterile inflammation. Therefore, we sought to determine whether early TLR4 blockade would be effective in reducing the inflammatory burden in islets pretransplant. METHODS: Islets from C57BL/6 mice were treated with a TLR4 antagonist during the pancreatic ductal perfusion and digestion steps of the isolation process. Islets were then analyzed for inflammation by RT-PCR and Western blot, and for viability and function in vitro. A syngeneic transplant model using a marginal mass of islets transplanted intraportally into mice with streptozotocin-induced diabetes was used to study transplant outcomes after early TLR4 blockade. RESULTS: Diabetic mice receiving 150 islets treated with early TLR4 blockade achieved euglycemia at a higher rate than mice receiving untreated islets (75% vs 29%; P < 0.05) and had improved long-term function (P < 0.05). Serum markers for islet damage and inflammation were significantly reduced posttransplant (P < 0.05). Both the expression of key inflammatory genes and the activation of mitogen-activated protein kinases were reduced by early TLR4 blockade. Islet viability was improved (P < 0.05) while preserving islet insulin secretory capacity postisolation. CONCLUSIONS: Early TLR4 blockade protects islets from sterile inflammation-mediated stress sustained during isolation and promotes positive transplant outcomes. Our findings support the use of early TLR4 blockade during clinical islet isolation procedures to reduce pretransplant inflammation and improve transplant outcomes.

Ex-vivo generation of drug-eluting islets improves transplant outcomes by inhibiting TLR4-Mediated NFkB upregulation.

The systemic administration of immunosuppressive and anti-inflammatory drugs is routinely employed in organ transplantation to minimize graft rejection and improve graft survival. Localized drug delivery has the potential to improve transplant outcomes by providing sustained exposure to efficacious drug concentrations while avoiding systemic immunosuppression and off-target effects. Here, we describe the synthesis of a novel prodrug and its direct covalent conjugation to pancreatic islets via a cleavable linker. Post-transplant, linker hydrolysis results in the release of a potent anti-inflammatory antagonist of TLR4, localized to the site of implantation. This covalent islet modification significantly reduces the time and the minimal effective dose of islets necessary to achieve normoglycemia in a murine transplantation model. In streptozotocin-induced diabetic C57BL/6 mice a syngeneic transplant of ∼100 modified islets achieved a 100% cure rate by the end of a 4-week monitoring period, compared to a 0% cure rate for untreated control islets. Overall, this direct prodrug conjugation to islets is well tolerated and preserves their functionality while affording significantly superior transplant outcomes. The development of drug-eluting tissues that deliver sustained and localized doses of small-molecule therapeutics represents a novel pathway for enhancing success in transplantation.

Islet damage during isolation as assessed by miRNAs and the correlation of miRNA levels with posttransplantation outcome in islet autotransplantation.

High-quality pancreatic islets are essential for better posttransplantation endocrine function in total pancreatectomy with islet autotransplantation (TPIAT), yet stress during the isolation process affects quality and yield. We analyzed islet-enriched microRNAs (miRNAs) -375 and -200c released during isolation to assess damage and correlated the data with posttransplantation endocrine function. The absolute concentration of miR-375, miR-200c, and C-peptide was measured in various islet isolation steps, including digestion, dilution, recombination, purification, and bagging, in 12 cases of TPIAT. Posttransplantation glycemic control was monitored through C-peptide, hemoglobin A1c , insulin requirement, and SUITO index. The amount of miR-375 released was significantly higher during enzymatic digestion followed by the islet bagging (P < .001). Mir-200c mirrored these changes, albeit at lower concentrations. In contrast, the C-peptide amount was significantly higher in the purification and bagging steps (P < .001). Lower amounts of miR-375 were associated with a lower 6-month insulin requirement (P = .01) and lower hemoglobin A1c (P = .04). Measurement of the absolute quantity of miRNA-375 and -200c released during islet isolation is a useful tool to assess islet damage. The quantity of released miRNA is indicative of posttransplantation endocrine function in TPIAT patients.