ABSTRACT
Clade I monkeypox virus (MPXV), which can cause severe illness in more people than clade II MPXVs, is endemic in the Democratic Republic of the Congo (DRC), but the country has experienced an increase in suspected cases during 2023-2024. In light of the 2022 global outbreak of clade II mpox, the increase in suspected clade I cases in DRC raises concerns that the virus could spread to other countries and underscores the importance of coordinated, urgent global action to support DRC's efforts to contain the virus. To date, no cases of clade I mpox have been detected outside of countries in Central Africa where the virus is endemic. CDC and other partners are working to support DRC's response. In addition, CDC is enhancing U.S. preparedness by raising awareness, strengthening surveillance, expanding diagnostic testing capacity for clade I MPXV, ensuring appropriate specimen handling and waste management, emphasizing the importance of appropriate medical treatment, and communicating guidance on the recommended contact tracing, containment, behavior modification, and vaccination strategies.
Subject(s)
Disease Outbreaks , Mpox (monkeypox) , Democratic Republic of the Congo/epidemiology , Humans , United States/epidemiology , Mpox (monkeypox)/epidemiology , Disease Outbreaks/prevention & control , Centers for Disease Control and Prevention, U.S. , Monkeypox virus/isolation & purificationABSTRACT
AIMS/HYPOTHESIS: Tractable precision biomarkers to identify immunotherapy responders are lacking in type 1 diabetes. We hypothesised that proinsulin:C-peptide (PI:C) ratios, a readout of beta cell stress, could provide insight into type 1 diabetes progression and responses to immunotherapy. METHODS: In this post hoc analysis, proinsulin and C-peptide levels were determined in baseline serum samples from 63 participants with stage 2 type 1 diabetes in the longitudinal TrialNet Teplizumab Prevention Study (n=41 in the teplizumab arm; n=22 in the placebo arm). In addition, previously tested demographic, C-peptide, glucose and proinsulin data were used for the new data analyses. The ratio of intact (unprocessed) proinsulin to C-peptide was analysed and relationships with progression to stage 3 diabetes were investigated. RESULTS: Elevated baseline PI:C was strongly associated with more rapid progression of diabetes in both the placebo and teplizumab treatment groups, but teplizumab abrogated the impact of high pre-treatment PI:C on type 1 diabetes progression. Differential responses of drug treatment in those with high vs low PI:C ratios were independent of treatment effects of teplizumab on the PI:C ratio or on relevant immune cells. CONCLUSIONS/INTERPRETATION: High pre-treatment PI:C identified individuals with stage 2 type 1 diabetes who were exhibiting rapid progression to stage 3 disease and who displayed benefit from teplizumab treatment. These data suggest that readouts of active disease, such as PI:C ratio, could serve to identify optimal candidates or timing for type 1 diabetes disease-modifying therapies.
Subject(s)
Diabetes Mellitus, Type 1 , Proinsulin , Humans , C-Peptide , Antibodies, Monoclonal, Humanized/therapeutic use , Insulin/metabolismABSTRACT
Since May 2022, mpox has been identified in 108 countries without endemic disease; most cases have been in gay, bisexual, or other men who have sex with men. To determine number of missed cases, we conducted 2 studies during June-September 2022: a prospective serologic survey detecting orthopoxvirus antibodies among men who have sex with men in San Francisco, California, and a retrospective monkeypox virus PCR testing of swab specimens submitted for other infectious disease testing among all patients across the United States. The serosurvey of 225 participants (median age 34 years) detected 18 (8.0%) who were orthopoxvirus IgG positive and 3 (1.3%) who were also orthopoxvirus IgM positive. The retrospective PCR study of 1,196 patients (median age 30 years; 54.8% male) detected 67 (5.6%) specimens positive for monkeypox virus. There are likely few undiagnosed cases of mpox in regions where sexual healthcare is accessible and patient and clinician awareness about mpox is increased.
Subject(s)
Mpox (monkeypox) , Orthopoxvirus , Sexual and Gender Minorities , Humans , Male , United States/epidemiology , Adult , Female , Monkeypox virus/genetics , Mpox (monkeypox)/diagnosis , Mpox (monkeypox)/epidemiology , Prevalence , Homosexuality, Male , Prospective Studies , Retrospective Studies , Disease OutbreaksABSTRACT
Hematopoietic and nervous systems are linked via innervation of bone marrow (BM) niche cells. Hematopoietic stem/progenitor cells (HSPCs) express neurotransmitter receptors, such as the γ-aminobutyric acid (GABA) type B receptor subunit 1 (GABBR1), suggesting that HSPCs could be directly regulated by neurotransmitters like GABA that directly bind to GABBR1. We performed imaging mass spectrometry and found that the endogenous GABA molecule is regionally localized and concentrated near the endosteum of the BM niche. To better understand the role of GABBR1 in regulating HSPCs, we generated a constitutive Gabbr1-knockout mouse model. Analysis revealed that HSPC numbers were significantly reduced in the BM compared with wild-type littermates. Moreover, Gabbr1-null hematopoietic stem cells had diminished capacity to reconstitute irradiated recipients in a competitive transplantation model. Gabbr1-null HSPCs were less proliferative under steady-state conditions and upon stress. Colony-forming unit assays demonstrated that almost all Gabbr1-null HSPCs were in a slow or noncycling state. In vitro differentiation of Gabbr1-null HSPCs in cocultures produced fewer overall cell numbers with significant defects in differentiation and expansion of the B-cell lineage. To determine whether a GABBR1 agonist could stimulate human umbilical cord blood (UCB) HSPCs, we performed brief ex vivo treatment prior to transplant into immunodeficient mice, with significant increases in long-term engraftment of HSPCs compared with GABBR1 antagonist or vehicle treatments. Our results indicate a direct role for GABBR1 in HSPC proliferation, and identify a potential target to improve HSPC engraftment in clinical transplantation.
Subject(s)
Hematopoietic Stem Cells/cytology , Receptors, GABA-B/physiology , Animals , B-Lymphocytes/pathology , Baclofen/analogs & derivatives , Baclofen/pharmacology , Bone Marrow/innervation , Bone Marrow/metabolism , Bone Marrow Transplantation , Cell Division , Cell Lineage , Female , Gene Expression Regulation , Hematopoietic Stem Cells/metabolism , Human Umbilical Vein Endothelial Cells/transplantation , Humans , Lymphopenia/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Mice, Knockout , Mice, SCID , Radiation Chimera , Receptors, GABA-B/deficiency , Receptors, GABA-B/genetics , Stem Cell NicheABSTRACT
Importance: Near normalization of glucose levels instituted immediately after diagnosis of type 1 diabetes has been postulated to preserve pancreatic beta cell function by reducing glucotoxicity. Previous studies have been hampered by an inability to achieve tight glycemic goals. Objective: To determine the effectiveness of intensive diabetes management to achieve near normalization of glucose levels on preservation of pancreatic beta cell function in youth with newly diagnosed type 1 diabetes. Design, Setting, and Participants: This randomized, double-blind, clinical trial was conducted at 6 centers in the US (randomizations from July 20, 2020, to October 13, 2021; follow-up completed September 15, 2022) and included youths with newly diagnosed type 1 diabetes aged 7 to 17 years. Interventions: Random assignment to intensive diabetes management, which included use of an automated insulin delivery system (n = 61), or standard care, which included use of a continuous glucose monitor (n = 52), as part of a factorial design in which participants weighing 30 kg or more also were assigned to receive either oral verapamil or placebo. Main Outcomes and Measures: The primary outcome was mixed-meal tolerance test-stimulated C-peptide area under the curve (a measure of pancreatic beta cell function) 52 weeks from diagnosis. Results: Among 113 participants (mean [SD] age, 11.8 [2.8] years; 49 females [43%]; mean [SD] time from diagnosis to randomization, 24 [5] days), 108 (96%) completed the trial. The mean C-peptide area under the curve decreased from 0.57 pmol/mL at baseline to 0.45 pmol/mL at 52 weeks in the intensive management group, and from 0.60 to 0.50 pmol/mL in the standard care group (treatment group difference, -0.01 [95% CI, -0.11 to 0.10]; P = .89). The mean time in the target range of 70 to 180 mg/dL, measured with continuous glucose monitoring, at 52 weeks was 78% in the intensive management group vs 64% in the standard care group (adjusted difference, 16% [95% CI, 10% to 22%]). One severe hypoglycemia event and 1 diabetic ketoacidosis event occurred in each group. Conclusions and Relevance: In youths with newly diagnosed type 1 diabetes, intensive diabetes management, which included automated insulin delivery, achieved excellent glucose control but did not affect the decline in pancreatic C-peptide secretion at 52 weeks. Trial Registration: ClinicalTrials.gov Identifier: NCT04233034.
Subject(s)
Diabetes Mellitus, Type 1 , Insulin-Secreting Cells , Female , Adolescent , Humans , Child , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/adverse effects , Hypoglycemic Agents/administration & dosage , Blood Glucose/drug effects , Insulin-Secreting Cells/drug effects , C-Peptide/pharmacology , C-Peptide/therapeutic use , Double-Blind Method , Glycemic Control , Blood Glucose Self-Monitoring , Glycated Hemoglobin , Insulin/adverse effects , Insulin/administration & dosageABSTRACT
Importance: In preclinical studies, thioredoxin-interacting protein overexpression induces pancreatic beta cell apoptosis and is involved in glucotoxicity-induced beta cell death. Calcium channel blockers reduce these effects and may be beneficial to beta cell preservation in type 1 diabetes. Objective: To determine the effect of verapamil on pancreatic beta cell function in children and adolescents with newly diagnosed type 1 diabetes. Design, Setting, and Participants: This double-blind, randomized clinical trial including children and adolescents aged 7 to 17 years with newly diagnosed type 1 diabetes who weighed 30 kg or greater was conducted at 6 centers in the US (randomized participants between July 20, 2020, and October 13, 2021) and follow-up was completed on September 15, 2022. Interventions: Participants were randomly assigned 1:1 to once-daily oral verapamil (n = 47) or placebo (n = 41) as part of a factorial design in which participants also were assigned to receive either intensive diabetes management or standard diabetes care. Main Outcomes and Measures: The primary outcome was area under the curve values for C-peptide level (a measure of pancreatic beta cell function) stimulated by a mixed-meal tolerance test at 52 weeks from diagnosis of type 1 diabetes. Results: Among 88 participants (mean age, 12.7 [SD, 2.4] years; 36 were female [41%]; and the mean time from diagnosis to randomization was 24 [SD, 4] days), 83 (94%) completed the trial. In the verapamil group, the mean C-peptide area under the curve was 0.66 pmol/mL at baseline and 0.65 pmol/mL at 52 weeks compared with 0.60 pmol/mL at baseline and 0.44 pmol/mL at 52 weeks in the placebo group (adjusted between-group difference, 0.14 pmol/mL [95% CI, 0.01 to 0.27 pmol/mL]; P = .04). This equates to a 30% higher C-peptide level at 52 weeks with verapamil. The percentage of participants with a 52-week peak C-peptide level of 0.2 pmol/mL or greater was 95% (41 of 43 participants) in the verapamil group vs 71% (27 of 38 participants) in the placebo group. At 52 weeks, hemoglobin A1c was 6.6% in the verapamil group vs 6.9% in the placebo group (adjusted between-group difference, -0.3% [95% CI, -1.0% to 0.4%]). Eight participants (17%) in the verapamil group and 8 participants (20%) in the placebo group had a nonserious adverse event considered to be related to treatment. Conclusions and Relevance: In children and adolescents with newly diagnosed type 1 diabetes, verapamil partially preserved stimulated C-peptide secretion at 52 weeks from diagnosis compared with placebo. Further studies are needed to determine the longitudinal durability of C-peptide improvement and the optimal length of therapy. Trial Registration: ClinicalTrials.gov Identifier: NCT04233034.
Subject(s)
Diabetes Mellitus, Type 1 , Insulin-Secreting Cells , Adolescent , Humans , Child , Female , Male , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/therapeutic use , C-Peptide/metabolism , C-Peptide/pharmacology , C-Peptide/therapeutic use , Double-Blind Method , Verapamil/adverse effects , Insulin-Secreting Cells/drug effectsABSTRACT
On May 17, 2022, the Massachusetts Department of Health announced the first suspected case of monkeypox associated with the global outbreak in a U.S. resident. On May 23, 2022, CDC launched an emergency response (1,2). CDC's emergency response focused on surveillance, laboratory testing, medical countermeasures, and education. Medical countermeasures included rollout of a national JYNNEOS vaccination strategy, Food and Drug Administration (FDA) issuance of an emergency use authorization to allow for intradermal administration of JYNNEOS, and use of tecovirimat for patients with, or at risk for, severe monkeypox. During May 17-October 6, 2022, a total of 26,384 probable and confirmed* U.S. monkeypox cases were reported to CDC. Daily case counts peaked during mid-to-late August. Among 25,001 of 25,569 (98%) cases in adults with information on gender identity, 23,683 (95%) occurred in cisgender men. Among 13,997 cisgender men with information on recent sexual or close intimate contact,§ 10,440 (75%) reported male-to-male sexual contact (MMSC) ≤21 days preceding symptom onset. Among 21,211 (80%) cases in persons with information on race and ethnicity,¶ 6,879 (32%), 6,628 (31%), and 6,330 (30%) occurred in non-Hispanic Black or African American (Black), Hispanic or Latino (Hispanic), and non-Hispanic White (White) persons, respectively. Among 5,017 (20%) cases in adults with information on HIV infection status, 2,876 (57%) had HIV infection. Prevention efforts, including vaccination, should be prioritized among persons at highest risk within groups most affected by the monkeypox outbreak, including gay, bisexual, and other men who have sex with men (MSM); transgender, nonbinary, and gender-diverse persons; racial and ethnic minority groups; and persons who are immunocompromised, including persons with advanced HIV infection or newly diagnosed HIV infection.
Subject(s)
HIV Infections , Mpox (monkeypox) , Sexual and Gender Minorities , Adult , United States/epidemiology , Humans , Male , Female , Homosexuality, Male , Ethnicity , HIV Infections/prevention & control , Mpox (monkeypox)/epidemiology , Minority Groups , Gender Identity , Cause of Death , Disease OutbreaksABSTRACT
Human monkeypox is caused by Monkeypox virus (MPXV), an Orthopoxvirus, previously rare in the United States (1). The first U.S. case of monkeypox during the current outbreak was identified on May 17, 2022 (2). As of September 28, 2022, a total of 25,341 monkeypox cases have been reported in the United States.* The outbreak has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) (3). JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic), administered subcutaneously as a 2-dose (0.5 mL per dose) series with doses administered 4 weeks apart, was approved by the Food and Drug Administration (FDA) in 2019 to prevent smallpox and monkeypox infection (4). U.S. distribution of JYNNEOS vaccine as postexposure prophylaxis (PEP) for persons with known exposures to MPXV began in May 2022. A U.S. national vaccination strategy for expanded PEP, announced on June 28, 2022, recommended subcutaneous vaccination of persons with known or presumed exposure to MPXV, broadening vaccination eligibility. FDA emergency use authorization (EUA) of intradermal administration of 0.1 mL of JYNNEOS on August 9, 2022, increased vaccine supply (5). As of September 28, 2022, most vaccine has been administered as PEP or expanded PEP. Because of the limited amount of time that has elapsed since administration of initial vaccine doses, as of September 28, 2022, relatively few persons in the current outbreak have completed the recommended 2-dose series.§ To examine the incidence of monkeypox among persons who were unvaccinated and those who had received ≥1 JYNNEOS vaccine dose, 5,402 reported monkeypox cases occurring among males¶ aged 18-49 years during July 31-September 3, 2022, were analyzed by vaccination status across 32 U.S. jurisdictions.** Average monkeypox incidence (cases per 100,000) among unvaccinated persons was 14.3 (95% CI = 5.0-41.0) times that among persons who received 1 dose of JYNNEOS vaccine ≥14 days earlier. Monitoring monkeypox incidence by vaccination status in timely surveillance data might provide early indications of vaccine-related protection that can be confirmed through other well-controlled vaccine effectiveness studies. This early finding suggests that a single dose of JYNNEOS vaccine provides some protection against monkeypox infection. The degree and durability of such protection is unknown, and it is recommended that people who are eligible for monkeypox vaccination receive the complete 2-dose series.
Subject(s)
Mpox (monkeypox) , Sexual and Gender Minorities , Smallpox Vaccine , Homosexuality, Male , Humans , Incidence , Male , Mpox (monkeypox)/epidemiology , Mpox (monkeypox)/prevention & control , United States/epidemiologyABSTRACT
As of October 28, 2022, a total of 28,244* monkeypox (mpox) cases have been reported in the United States during an outbreak that has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) (1). JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic), administered subcutaneously as a 2-dose (0.5 mL per dose) series (with doses administered 4 weeks apart), was approved by the Food and Drug Administration (FDA) in 2019 to prevent smallpox and mpox disease (2); an FDA Emergency Use Authorization issued on August 9, 2022, authorized intradermal administration of 0.1 mL per dose, increasing the number of persons who could be vaccinated with the available vaccine supply (3). A previous comparison of mpox incidence during July 31-September 3, 2022, among unvaccinated, but vaccine-eligible men aged 18-49 years and those who had received ≥1 JYNNEOS vaccine dose in 32 U.S. jurisdictions, found that incidence among unvaccinated persons was 14 times that among vaccinated persons (95% CI = 5.0-41.0) (4). During September 4-October 1, 2022, a total of 205,504 persons received JYNNEOS vaccine dose 2 in the United States.§ To further examine mpox incidence among persons who were unvaccinated and those who had received either 1 or 2 JYNNEOS doses, investigators analyzed data on 9,544 reported mpox cases among men¶ aged 18-49 years during July 31-October 1, 2022, from 43 U.S. jurisdictions,** by vaccination status. During this study period, mpox incidence (cases per 100,000 population at risk) among unvaccinated persons was 7.4 (95% CI = 6.0-9.1) times that among persons who received only 1 dose of JYNNEOS vaccine ≥14 days earlier and 9.6 (95% CI = 6.9-13.2) times that among persons who received dose 2 ≥14 days earlier. The observed distribution of subcutaneous and intradermal routes of administration of dose 1 among vaccinated persons with mpox was not different from the expected distribution. This report provides additional data suggesting JYNNEOS vaccine provides protection against mpox, irrespective of whether the vaccine is administered intradermally or subcutaneously. The degree and durability of such protection remains unclear. Persons eligible for mpox vaccination should receive the complete 2-dose series to optimize strength of protection (5).
Subject(s)
Mpox (monkeypox) , Sexual and Gender Minorities , Humans , Male , Homosexuality, Male , United States/epidemiology , United States Food and Drug Administration , Mpox (monkeypox)/prevention & control , Smallpox Vaccine/administration & dosageABSTRACT
AIMS/HYPOTHESIS: We aimed to compare characteristics of individuals identified in the peri-diagnostic range by Index60 (composite glucose and C-peptide measure) ≥2.00, 2 h OGTT glucose ≥11.1 mmol/l, or both. METHODS: We studied autoantibody-positive participants in the Type 1 Diabetes TrialNet Pathway to Prevention study who, at their baseline OGTT, had 2 h blood glucose ≥11.1 mmol/l and/or Index60 ≥2.00 (n = 354, median age = 11.2 years, age range = 1.7-46.6; 49% male, 83% non-Hispanic White). Type 1 diabetes-relevant characteristics (e.g., age, C-peptide, autoantibodies, BMI) were compared among three mutually exclusive groups: 2 h glucose ≥11.1 mmol/l and Index60 <2.00 [Glu(+), n = 76], 2 h glucose <11.1 mmol/l and Index60 ≥2.00 [Ind(+), n = 113], or both 2 h glucose ≥11.1 mmol/l and Index60 ≥2.00 [Glu(+)/Ind(+), n = 165]. RESULTS: Participants in Glu(+), vs those in Ind(+) or Glu(+)/Ind(+), were older (mean ages = 22.9, 11.8 and 14.7 years, respectively), had higher early (30-0 min) C-peptide response (1.0, 0.50 and 0.43 nmol/l), higher AUC C-peptide (2.33, 1.13 and 1.10 nmol/l), higher percentage of overweight/obesity (58%, 16% and 30%) (all comparisons, p < 0.0001), and a lower percentage of multiple autoantibody positivity (72%, 92% and 93%) (p < 0.001). OGTT-stimulated C-peptide and glucose patterns of Glu(+) differed appreciably from Ind(+) and Glu(+)/Ind(+). Progression to diabetes occurred in 61% (46/76) of Glu(+) and 63% (71/113) of Ind(+). Even though Index60 ≥2.00 was not a Pathway to Prevention diagnostic criterion, Ind(+) had a 4 year cumulative diabetes incidence of 95% (95% CI 86%, 98%). CONCLUSIONS/INTERPRETATION: Participants in the Ind(+) group had more typical characteristics of type 1 diabetes than participants in the Glu(+) did and were as likely to be diagnosed. However, unlike Glu(+) participants, Ind(+) participants were not identified at the baseline OGTT.
Subject(s)
Blood Glucose/metabolism , C-Peptide/blood , Decision Support Techniques , Diabetes Mellitus, Type 1/diagnosis , Glucose Tolerance Test , Islets of Langerhans/metabolism , Adolescent , Adult , Autoantibodies/blood , Biomarkers/blood , Child , Child, Preschool , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/immunology , Disease Progression , Early Diagnosis , Female , Humans , Infant , Islets of Langerhans/immunology , Male , Middle Aged , Predictive Value of Tests , Prognosis , Prospective Studies , Young AdultABSTRACT
BACKGROUND: Human immunodeficiency virus (HIV) may be related to cardiovascular disease through monocyte activation-associated endothelial dysfunction. METHODS: Blood samples from 15 HIV-negative participants (the uninfected group), 8 HIV-positive participants who were not receiving antiretroviral therapy (ART) (the infected, untreated group), and 15 HIV-positive participants who were receiving ART (the infected, treated group) underwent flow cytometry of endothelial colony-forming cells (ECFCs) and monocyte proportions. IncuCyte live cell imaging of 8 capillary proliferative capacity parameters were obtained from cord blood ECFCs treated with participant plasma. RESULTS: The ECFC percentage determined by flow cytometry was not different between the study groups; however, values of the majority of capillary proliferative capacity parameters (ie, cell area, network length, network branch points, number of networks, and average tube width uniformity) were significantly lower in infected, untreated participants as compared to values for uninfected participants or infected, treated participants (P < .00625 for all comparisons). CD14+CD16+ intermediate monocytes and soluble CD163 were significantly and negatively correlated with several plasma-treated, cord blood ECFC proliferative capacity parameters in the combined HIV-positive groups but not in the uninfected group. CONCLUSIONS: Cord blood ECFC proliferative capacity was significantly impaired by plasma from infected, untreated patients, compared with plasma from uninfected participants and from infected, treated participants. Several ECFC functional parameters were adversely associated with monocyte activation in the HIV-positive groups, thereby suggesting a mechanism by which HIV-related inflammation may impair vascular reparative potential and consequently increase the risk of cardiovascular disease during HIV infection.
Subject(s)
Endothelium/immunology , HIV Seronegativity/immunology , HIV Seropositivity/immunology , Monocytes , Stem Cells , Adult , Alkynes , Anti-HIV Agents/therapeutic use , Benzoxazines/therapeutic use , Cell Proliferation , Chemokine CCL5/blood , Cyclopropanes , Endothelium/pathology , Female , Fetal Blood , Flow Cytometry , GPI-Linked Proteins/metabolism , HIV Seropositivity/blood , HIV Seropositivity/drug therapy , Humans , Lipopolysaccharide Receptors/metabolism , Male , Middle Aged , Monocytes/metabolism , Neovascularization, Physiologic , Plasma/immunology , Prospective Studies , Receptors, IgG/metabolism , Stem Cells/physiology , Vascular Cell Adhesion Molecule-1/blood , Vascular Endothelial Growth Factor Receptor-1/blood , Vascular Endothelial Growth Factor Receptor-2/bloodABSTRACT
Histological analysis of donor pancreases coupled with measurement of serum C-peptide in clinical cohorts has challenged the idea that all beta cells are eventually destroyed in type 1 diabetes. These findings have raised a number of questions regarding how the remaining beta cells have escaped immune destruction, whether pools of 'sleeping' or dysfunctional beta cells could be rejuvenated and whether there is potential for new growth of beta cells. In this Review, we describe histological and in vivo evidence of persistent beta cells in type 1 diabetes and discuss the limitations of current methods to distinguish underlying beta cell mass in comparison with beta cell function. We highlight that evidence for new beta cell growth in humans many years from diagnosis is limited, and that this growth may be very minimal if at all present. We review recent contributions to the debate around beta cell abnormalities contributing to the pathogenesis of type 1 diabetes. We also discuss evidence for restoration of beta cell function, as opposed to mass, in recent-onset type 1 diabetes, but highlight the absence of data supporting functional recovery in the setting of long-duration diabetes. Finally, future areas of research are suggested to help resolve the source and phenotype of residual beta cells that persist in some, but not all, people with type 1 diabetes.
Subject(s)
Diabetes Mellitus, Type 1/physiopathology , Insulin-Secreting Cells/physiology , Biomarkers/blood , C-Peptide/blood , Diabetes Mellitus, Type 1/blood , Humans , Insulin/metabolism , Pancreas/metabolism , Phenotype , Research DesignABSTRACT
AIM: To evaluate whether ß cells continue to undergo death in the later stages of type 1 diabetes (T1D). MATERIALS AND METHODS: Fasting banked sera from a cross-section of 90 participants in the T1D Exchange Registry with longstanding T1D (median duration of 9 years) were analysed. Subjects were determined to be C-peptide (-) or (+) based on mixed-meal tolerance testing. Results were compared with 54 adult non-diabetic controls. Stimulated samples were assayed in a subset of subjects. Levels of unmethylated and methylated preproinsulin (INS) DNA were analysed using digital droplet PCR. RESULTS: Fasting and stimulated circulating unmethylated INS DNA levels were increased among both C-peptide (-) and C-peptide (+) subjects with longstanding T1D compared with non-diabetic controls (P < 0.01). Consistent with prior reports, unmethylated INS DNA values correlated with methylated INS DNA values, which were also elevated among T1D subjects (P < 0.001). There was wide variation in the effects of mixed-meal stimulation on DNA levels, with fasting values in the highest quartiles decreasing with stimulation (P < 0.05). CONCLUSIONS: These results could reflect ongoing ß cell death in individuals with longstanding T1D, even in the absence of detectable C-peptide production, suggesting that therapies targeting ß cell survival could be beneficial among individuals with longstanding T1D.
Subject(s)
DNA , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/epidemiology , Insulin , Protein Precursors , Adult , C-Peptide/blood , Case-Control Studies , DNA/blood , DNA/genetics , DNA Methylation , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/physiopathology , Female , Humans , Insulin/blood , Insulin/genetics , Insulin-Secreting Cells/metabolism , Male , Middle Aged , Protein Precursors/blood , Protein Precursors/genetics , Young AdultABSTRACT
BACKGROUND: In new onset type 1 diabetes (T1D), overall C-peptide measures such as area under the curve (AUC) C-peptide and peak C-peptide are useful for estimating the extent of ß-cell dysfunction, and for assessing responses to intervention therapy. However, measures of the timing of C-peptide responsiveness could have additional value. OBJECTIVES: We assessed the contribution of the timing of C-peptide responsiveness during oral glucose tolerance tests (OGTTs) to hemoglobin A1c (HbA1c) variation at T1D diagnosis. METHODS: We analyzed data from 85 individuals <18 years with OGTTs and HbA1c measurements at diagnosis. Overall [AUC and peak C-peptide] and timing measures [30-0 minute C-peptide (early); 60 to 120 minute C-peptide sum-30 minutes (late); 120/30 C-peptide; time to peak C-peptide] were utilized. RESULTS: At diagnosis, the mean (±SD) age was 11.2 ± 3.3 years, body mass index (BMI)-z was 0.4 ± 1.1, 51.0% were male. The average HbA1c was 43.54 ± 8.46 mmol/mol (6.1 ± 0.8%). HbA1c correlated inversely with the AUC C-peptide (P < 0.001), peak C-peptide (P < 0.001), early and late C-peptide responses (P < 0.001 each), and 120/30 C-peptide (P < 0.001). Those with a peak C-peptide occurring at ≤60 minutes had higher HbA1c values than those with peaks later (P = 0.003). HbA1c variance was better explained with timing measures added to regression models (R2 = 11.6% with AUC C-peptide alone; R2 = 20.0% with 120/30 C-peptide added; R2 = 13.7% with peak C-peptide alone, R2 = 20.4% with timing of the peak added). Similar associations were seen between the 2-hour glucose and the C-peptide measures. CONCLUSIONS: These findings show that the addition of timing measures of C-peptide responsiveness better explains HbA1c variation at diagnosis than standard measures alone.
Subject(s)
C-Peptide/metabolism , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/genetics , Glycated Hemoglobin/metabolism , Adolescent , Adult , Blood Glucose/genetics , Blood Glucose/metabolism , C-Peptide/analysis , Child , Child, Preschool , Diabetes Mellitus, Type 1/blood , Female , Genetic Association Studies , Glucose Tolerance Test , Glycated Hemoglobin/analysis , Humans , Infant , Male , Middle Aged , Time Factors , Young AdultABSTRACT
Recent work on the pathogenesis of type 1 diabetes has led to an evolving recognition of the heterogeneity of this disease, both with regards to clinical phenotype and responses to therapies to prevent or revert diabetes. This heterogeneity not only limits efforts to accurately predict clinical disease but also is reflected in differing responses to immunomodulatory therapeutics. Thus, there is a need for robust biomarkers of beta cell health, which could provide insight into pathophysiological differences in disease course, improve disease prediction, increase the understanding of therapeutic responses to immunomodulatory interventions and identify individuals most likely to benefit from these therapies. In this review, we outline current literature, limitations and future directions for promising circulating markers of beta cell stress and death in type 1 diabetes, including markers indicating abnormal prohormone processing, circulating RNAs and circulating DNAs.
Subject(s)
Biomarkers/blood , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/metabolism , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , HumansABSTRACT
AIMS/HYPOTHESIS: Improved biomarkers are acutely needed for the detection of developing type 1 diabetes, prior to critical loss of beta cell mass. We previously demonstrated that elevated beta cell microRNA 21-5p (miR-21-5p) in rodent and human models of type 1 diabetes increased beta cell apoptosis. We hypothesised that the inflammatory milieu of developing diabetes may also increase miR-21-5p in beta cell extracellular vesicle (EV) cargo and that circulating EV miR-21-5p would be increased during type 1 diabetes development. METHODS: MIN6 and EndoC-ßH1 beta cell lines and human islets were treated with IL-1ß, IFN-γ and TNF-α to mimic the inflammatory milieu of early type 1 diabetes. Serum was collected weekly from 8-week-old female NOD mice until diabetes onset. Sera from a cross-section of 19 children at the time of type 1 diabetes diagnosis and 16 healthy children were also analysed. EVs were isolated from cell culture media or serum using sequential ultracentrifugation or ExoQuick precipitation and EV miRNAs were assayed. RESULTS: Cytokine treatment in beta cell lines and human islets resulted in a 1.5- to threefold increase in miR-21-5p. However, corresponding EVs were further enriched for this miRNA, with a three- to sixfold EV miR-21-5p increase in response to cytokine treatment. This difference was only partially reduced by pre-treatment of beta cells with Z-VAD-FMK to inhibit cytokine-induced caspase activity. Nanoparticle tracking analysis showed cytokines to have no effect on the number of EVs, implicating specific changes within EV cargo as being responsible for the increase in beta cell EV miR-21-5p. Sequential ultracentrifugation to separate EVs by size suggested that this effect was mostly due to cytokine-induced increases in exosome miR-21-5p. Longitudinal serum collections from NOD mice showed that EVs displayed progressive increases in miR-21-5p beginning 3 weeks prior to diabetes onset. To validate the relevance to human diabetes, we assayed serum from children with new-onset type 1 diabetes compared with healthy children. While total serum miR-21-5p and total serum EVs were reduced in diabetic participants, serum EV miR-21-5p was increased threefold compared with non-diabetic individuals. By contrast, both serum and EV miR-375-5p were increased in parallel among diabetic participants. CONCLUSIONS/INTERPRETATION: We propose that circulating EV miR-21-5p may be a promising marker of developing type 1 diabetes. Additionally, our findings highlight that, for certain miRNAs, total circulating miRNA levels are distinct from circulating EV miRNA content.
Subject(s)
Biomarkers/metabolism , Cytokines/metabolism , Diabetes Mellitus, Type 1/metabolism , Insulin-Secreting Cells/metabolism , MicroRNAs/genetics , Animals , Apoptosis , Extracellular Vesicles , Female , Gene Expression Profiling , Humans , Inflammation , Interleukin-1beta/metabolism , Mice , Mice, Inbred NOD , MicroRNAs/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Electroacupuncture (EA) performed in rats and humans using limb acupuncture sites, LI-4 and LI-11, and GV-14 and GV-20 (humans) and Bai-hui (rats) increased functional connectivity between the anterior hypothalamus and the amygdala and mobilized mesenchymal stem cells (MSCs) into the systemic circulation. In human subjects, the source of the MSC was found to be primarily adipose tissue, whereas in rodents the tissue sources were considered more heterogeneous. Pharmacological disinhibition of rat hypothalamus enhanced sympathetic nervous system (SNS) activation and similarly resulted in a release of MSC into the circulation. EA-mediated SNS activation was further supported by browning of white adipose tissue in rats. EA treatment of rats undergoing partial rupture of the Achilles tendon resulted in reduced mechanical hyperalgesia, increased serum interleukin-10 levels and tendon remodeling, effects blocked in propranolol-treated rodents. To distinguish the afferent role of the peripheral nervous system, phosphoinositide-interacting regulator of transient receptor potential channels (Pirt)-GCaMP3 (genetically encoded calcium sensor) mice were treated with EA acupuncture points, ST-36 and LIV-3, and GV-14 and Bai-hui and resulted in a rapid activation of primary sensory neurons. EA activated sensory ganglia and SNS centers to mediate the release of MSC that can enhance tissue repair, increase anti-inflammatory cytokine production and provide pronounced analgesic relief. Stem Cells 2017;35:1303-1315.
Subject(s)
Central Nervous System/cytology , Electroacupuncture , Mesenchymal Stem Cells/cytology , Achilles Tendon/pathology , Acupuncture Points , Adipocytes/cytology , Adipose Tissue, Brown/cytology , Adipose Tissue, White/cytology , Animals , Antigens, CD/metabolism , Forelimb/physiology , Hindlimb/physiology , Humans , Hyperalgesia/therapy , Hypothalamus/cytology , Interleukin-10/blood , Macrophages/cytology , Mice , Nerve Net/physiology , Rats , Rupture , Sensory Receptor Cells/metabolism , Uncoupling Protein 1/metabolismABSTRACT
AIMS/HYPOTHESIS: The role of beta cell microRNA (miR)-21 in the pathophysiology of type 1 diabetes has been controversial. Here, we sought to define the context of beta cell miR-21 upregulation in type 1 diabetes and the phenotype of beta cell miR-21 overexpression through target identification. METHODS: Islets were isolated from NOD mice and mice treated with multiple low doses of streptozotocin, as a mouse model of diabetes. INS-1 832/13 beta cells and human islets were treated with IL-1ß, IFN-γ and TNF-α to mimic the milieu of early type 1 diabetes. Cells and islets were transfected with miR-21 mimics or inhibitors. Luciferase assays and polyribosomal profiling (PRP) were performed to define miR-21-target interactions. RESULTS: Beta cell miR-21 was increased in in vivo models of type 1 diabetes and cytokine-treated cells/islets. miR-21 overexpression decreased cell count and viability, and increased cleaved caspase 3 levels, suggesting increased cell death. In silico prediction tools identified the antiapoptotic mRNA BCL2 as a conserved miR-21 target. Consistent with this, miR-21 overexpression decreased BCL2 transcript and B cell lymphoma 2 (BCL2) protein production, while miR-21 inhibition increased BCL2 protein levels and reduced cleaved caspase 3 levels after cytokine treatment. miR-21-mediated cell death was abrogated in 828/33 cells, which constitutively overexpress Bcl2. Luciferase assays suggested a direct interaction between miR-21 and the BCL2 3' untranslated region. With miR-21 overexpression, PRP revealed a shift of the Bcl2 message towards monosome-associated fractions, indicating inhibition of Bcl2 translation. Finally, overexpression in dispersed human islets confirmed a reduction in BCL2 transcripts and increased cleaved caspase 3 production. CONCLUSIONS/INTERPRETATION: In contrast to the pro-survival role reported in other systems, our results demonstrate that miR-21 increases beta cell death via BCL2 transcript degradation and inhibition of BCL2 translation.
Subject(s)
Diabetes Mellitus, Type 1/genetics , MicroRNAs/metabolism , Animals , Fluorescent Antibody Technique , Humans , Immunoblotting , Insulin-Secreting Cells/metabolism , Interferon-gamma/metabolism , Interleukin-1beta/metabolism , Male , Mice , Mice, Inbred NOD , MicroRNAs/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Tumor Necrosis Factor-alpha/metabolismABSTRACT
The hallmark of type 1 diabetes (T1D) is a decline in functional ß-cell mass arising as a result of autoimmunity. Immunomodulatory interventions at disease onset have resulted in partial stabilization of ß-cell function, but full recovery of insulin secretion has remained elusive. Revised efforts have focused on disease prevention through interventions administered at earlier disease stages. To support this paradigm, there is a parallel effort ongoing to identify circulating biomarkers that have the potential to identify stress and death of the islet ß-cells. Whereas no definitive biomarker(s) have been fully validated, several approaches hold promise that T1D can be reliably identified in the pre-symptomatic phase, such that either ß-cell preservation or immunomodulatory agents might be employed in at-risk populations. This review summarizes the most promising protein- and nucleic acid-based biomarkers discovered to date and reviews the context in which they have been studied.
Subject(s)
Diabetes Mellitus, Type 1/physiopathology , Insulin-Secreting Cells/physiology , Biomarkers , C-Peptide/blood , DNA Methylation , Diabetes Mellitus, Type 1/blood , Humans , Proinsulin/blood , RNA, Untranslated/bloodABSTRACT
Adipose-derived stromal/stem cells (ASCs) ameliorate hyperglycemia in rodent models of islet transplantation and autoimmune diabetes, yet the precise human ASC (hASC)-derived factors responsible for these effects remain largely unexplored. Here, we show that systemic administration of hASCs improved glucose tolerance, preserved ß cell mass, and increased ß cell proliferation in streptozotocin-treated nonobese diabetic/severe combined immunodeficient mice. Coculture experiments combining mouse or human islets with hASCs demonstrated that islet viability and function were improved by hASCs following prolonged culture or treatment with proinflammatory cytokines. Analysis of hASC-derived factors revealed vascular endothelial growth factor and tissue inhibitor of metalloproteinase 1 (TIMP-1) to be highly abundant factors secreted by hASCs. Notably, TIMP-1 secretion increased in the presence of islet stress from cytokine treatment, while TIMP-1 blockade was able to abrogate in vitro prosurvival effects of hASCs. Following systemic administration by tail vein injection, hASCs were detected in the pancreas and human TIMP-1 was increased in the serum of injected mice, while recombinant TIMP-1 increased viability in INS-1 cells treated with interleukin-1beta, interferon-gamma, and tumor necrosis factor alpha. In aggregate, our data support a model whereby factors secreted by hASCs, such as TIMP-1, are able to mitigate against ß cell death in rodent and in vitro models of type 1 diabetes through a combination of local paracrine as well as systemic effects.