BACKGROUND. The duration and patterns of β cell dysfunction during type 1 diabetes (T1D) development have not been fully defined. METHODS. Metabolic measures derived from oral glucose tolerance tests (OGTTs) were compared between autoantibody-positive (aAb+) individuals followed in the TrialNet Pathway to Prevention study who developed diabetes after 5 or more years or less than 5 years of longitudinal follow-up (Progressors≥5, n = 75; Progressors<5, n = 474) and 144 aAb-negative (aAb–) relatives. RESULTS. Mean age at study entry was 15.0 ± 12.6 years for Progressors≥5; 12.0 ± 9.1 for Progressors<5; and 16.3 ± 10.4 for aAb– relatives. At baseline, Progressors≥5 already exhibited significantly lower fasting C-peptide (P < 0.01), C-peptide AUC (P < 0.001), and early C-peptide responses (30- to 0-minute C-peptide; P < 0.001) compared with aAb– relatives, while 2-hour glucose (P = 0.03), glucose AUC (<0.001), and Index60 (<0.001) were all higher. Despite significant baseline impairment, metabolic measures in Progressors≥5 were relatively stable until 2 years prior to T1D diagnosis, when there was accelerated C-peptide decline and rising glycemia from 2 years until diabetes diagnosis. Remarkably, patterns of progression within 3 years of diagnosis were nearly identical between Progressors≥5 and Progressors<5. CONCLUSION. These data provide insight into the chronicity of β cell dysfunction in T1D and indicate that β cell dysfunction may precede diabetes diagnosis by more than 5 years in a subset of aAb+ individuals. Even among individuals with varying lengths of aAb positivity, our findings indicate that patterns of metabolic decline are uniform within the last 3 years of progression to T1D. TRIAL REGISTRATION. Clinicaltrials.gov NCT00097292. FUNDING. The Type 1 Diabetes TrialNet Study Group is a clinical trials network currently funded by the NIH through the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Allergy and Infectious Diseases, and The Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Juvenile Diabetes Research Foundation.
Carmella Evans-Molina, Emily K. Sims, Linda A. DiMeglio, Heba M. Ismail, Andrea K. Steck, Jerry P. Palmer, Jeffrey P. Krischer, Susan Geyer, Ping Xu, Jay M. Sosenko, the Type 1 Diabetes TrialNet Study Group
BACKGROUND. Disruption of cystic fibrosis transmembrane conductance regulator (CFTR) anion channel function causes cystic fibrosis (CF), and lung disease produces most of the mortality. Loss of CFTR-mediated HCO3– secretion reduces the pH of airway surface liquid (ASL) in vitro and in neonatal humans and pigs in vivo. However, we previously found that, in older children and adults, ASL pH does not differ between CF and non-CF. Here, we tested whether the pH of CF ASL increases with time after birth. Finding that it did suggested that adaptations by CF airways increase ASL pH. This conjecture predicted that increasing CFTR activity in CF airways would further increase ASL pH and also that increasing CFTR activity would correlate with increases in ASL pH. METHODS. To test for longitudinal changes, we measured ASL pH in newborns and then at 3-month intervals. We also studied people with CF (bearing G551D or R117H mutations), in whom we could acutely stimulate CFTR activity with ivacaftor. To gauge changes in CFTR activity, we measured changes in sweat Cl– concentration immediately before and 48 hours after starting ivacaftor. RESULTS. Compared with that in the newborn period, ASL pH increased by 6 months of age. In people with CF bearing G551D or R117H mutations, ivacaftor did not change the average ASL pH; however reductions in sweat Cl– concentration correlated with elevations of ASL pH. Reductions in sweat Cl– concentration also correlated with improvements in pulmonary function. CONCLUSIONS. Our results suggest that CFTR-independent mechanisms increase ASL pH in people with CF. We speculate that CF airway disease, which begins soon after birth, is responsible for the adaptation. FUNDING. Vertex Inc., the NIH (P30DK089507, 1K08HL135433, HL091842, HL136813, K24HL102246), the Cystic Fibrosis Foundation (SINGH17A0 and SINGH15R0), and the Burroughs Wellcome Fund.
Mahmoud H. Abou Alaiwa, Jan L. Launspach, Brenda Grogan, Suzanne Carter, Joseph Zabner, David A. Stoltz, Pradeep K. Singh, Edward F. McKone, Michael J. Welsh
BACKGROUND. Exercise has profound pleiotropic health benefits, yet the underlying mechanisms remain incompletely understood. Endocrine FGF21, bile acids (BAs), and BA-induced FGF19 have emerged as metabolic signaling molecules. Here, we investigated if dissimilar modes of exercise, resistance exercise (RE) and endurance exercise (EE), regulate plasma BAs, FGF19, and FGF21 in humans. METHODS. Ten healthy, moderately trained males were enrolled in a randomized crossover study of 1 hour of bicycling at 70% of VO2peak (EE) and 1 hour of high-volume RE. Hormones and metabolites were measured in venous blood and sampled before and after exercise and at 15, 30, 60, 90, 120, and 180 minutes after exercise. RESULTS. We observed exercise mode–specific changes in plasma concentrations of FGF19 and FGF21. Whereas FGF19 decreased following RE (P < 0.001), FGF21 increased in response to EE (P < 0.001). Total plasma BAs decreased exclusively following RE (P < 0.05), but the composition of BAs changed in response to both types of exercise. Notably, circulating levels of the potent TGR5 receptor agonist, lithocholic acid, increased with both types of exercise (P < 0.001). CONCLUSION. This study reveals divergent effects of EE and RE on circulating concentrations of the BA species, FGF19, and FGF21. We identify temporal relationships between decreased BA and FGF19 following RE and a sharp disparity in FGF21 concentrations, with EE eliciting a clear increase parallel to that of glucagon. FUNDING. The Novo Nordisk Foundation (NNF17OC0026114) and the Lundbeck Foundation (R238-2016-2859).
Thomas Morville, Ronni E. Sahl, Samuel A.J. Trammell, Jens S. Svenningsen, Matthew P. Gillum, Jørn W. Helge, Christoffer Clemmensen
BACKGROUND. The induction of beige adipocytes in s.c. white adipose tissue (WAT) depots of humans is postulated to improve glucose and lipid metabolism in obesity. The ability of obese, insulin-resistant humans to induce beige adipose tissue is unknown. METHODS. We exposed lean and obese research participants to cold (30-minute ice pack application each day for 10 days of the upper thigh) or treated them with the β3 agonist mirabegron. We determined beige adipose marker expression by IHC and quantitative PCR, and we analyzed mitochondrial bioenergetics and UCP activity with an Oxytherm system. RESULTS. Cold significantly induced UCP1 and TMEM26 protein in both lean and obese subjects, and this response was not associated with age. Interestingly, these proteins increased to the same extent in s.c. WAT of the noniced contralateral leg, indicating a crossover effect. We further analyzed the bioenergetics of purified mitochondria from the abdominal s.c. WAT of cold-treated subjects and determined that repeat ice application significantly increased uncoupled respiration, consistent with the UCP1 protein induction and subsequent activation. Cold also increased State 3 and maximal respiration, and this effect on mitochondrial bioenergetics was stronger in summer than winter. Chronic treatment (10 weeks; 50 mg/day) with the β3 receptor agonist mirabegron induces UCP1, TMEM26, CIDEA, and phosphorylation of HSL on serine660 in obese subjects. CONCLUSION. Cold or β3 agonists cause the induction of beige adipose tissue in human s.c. WAT; this phenomenon may be exploited to increase beige adipose in older, insulin-resistant, obese individuals. TRIAL REGISTRATION. Clinicaltrials.gov NCT02596776, NCT02919176. FUNDING. NIH (DK107646, DK112282, P20GM103527, and by CTSA grant UL1TR001998).
Brian S. Finlin, Hasiyet Memetimin, Amy L. Confides, Ildiko Kasza, Beibei Zhu, Hemendra J. Vekaria, Brianna Harfmann, Kelly A. Jones, Zachary R. Johnson, Philip M. Westgate, Caroline M. Alexander, Patrick G. Sullivan, Esther E. Dupont-Versteegden, Philip A. Kern
To what extent does the subarachnoid cerebrospinal fluid (CSF) compartment communicate directly with the extravascular compartment of human brain tissue? Interconnection between the subarachnoid CSF compartment and brain perivascular spaces is reported in some animal studies, but with controversy, and in vivo CSF tracer studies in humans are lacking. In the present work, we examined the distribution of a CSF tracer in the human brain by MRI over a prolonged time span. For this, we included a reference cohort, representing close to healthy individuals, and a cohort of patients with dementia and anticipated compromise of CSF circulation (idiopathic normal pressure hydrocephalus). The MRI contrast agent gadobutrol, which is confined to the extravascular brain compartment by the intact blood-brain barrier, was used as a CSF tracer. Standardized T1-weighted MRI scans were performed before and after intrathecal gadobutrol at defined time points, including at 24 hours, 48 hours, and 4 weeks. All MRI scans were aligned and brain regions were segmented using FreeSurfer, and changes in normalized T1 signals over time were quantified as percentage change from baseline. The study provides in vivo evidence of access to all human brain subregions of a substance administered intrathecally. Clearance of the tracer substance was delayed in the dementia cohort. These observations translate previous findings in animal studies into humans and open new prospects concerning intrathecal treatment regimens, extravascular contrast-enhanced MRI, and assessment of brain clearance function.
Geir Ringstad, Lars M. Valnes, Anders M. Dale, Are H. Pripp, Svein-Are S. Vatnehol, Kyrre E. Emblem, Kent-Andre Mardal, Per K. Eide
BACKGROUND. The red cell distribution width (RDW) is associated with health outcomes. Whether non-RDW risk information is contained in RBC sizes is unknown. This study evaluated the association of the percentage of extreme macrocytic RBCs (%Macro, RBC volume > 120 fl) and microcytic RBCs (%Micro, RBC volume < 60 fl) and the RDW–size distribution (RDW-sd) with mortality and morbidity. METHODS. Patients (females, n = 165,770; males, n = 100,210) at Intermountain Healthcare were studied if they had a hematology panel between May 2014 and September 2016. Adjusted sex-specific associations of %Macro/%Micro and RDW-sd with mortality and 33 morbidities were evaluated. RESULTS. Among females with fourth-quartile values of %Macro quartile and %Micro (referred to throughout as 4/4), there was an average of 7.2 morbidities versus 2.9 in the lowest risk (LR1) categories, 1/1, 1/2, 2/1, and 2/2 (P < 0.001). Among males, those in the 4/4 category had 8.0 morbidities, while those in the LR1 had 3.4 (P < 0.001). Cox regressions found %Macro/%Micro (4/4 vs. LR1, females: hazard ratio [HR] = 1.97 [95% CI = 1.53, 2.54]; males: HR = 2.17 [CI = 1.72, 2.73]), RDW-sd (quartile 4 vs. 1, females: HR = 1.33 [CI = 1.04, 1.69]; males: HR = 1.41 [CI = 1.10, 1.80]), and RDW (quartile 4 vs. 1, females: HR = 1.59 [CI = 1.26, 2.00]; males: HR = 1.23 [CI = 0.99, 1.52]) independently predicted mortality. Limitations include that the observational design did not reveal causality and unknown confounders may be unmeasured. CONCLUSIONS. Concomitantly elevated %Macro and %Micro predicted the highest mortality risk and the greatest number of morbidities, revealing predictive ability of RBC volume beyond what is measured clinically. Mechanistic investigations are needed to explain the biological basis of these observations. FUNDING. This study was supported by internal Intermountain Heart Institute funds and in-kind support from Sysmex America Inc.
Benjamin D. Horne, Joseph B. Muhlestein, Sterling T. Bennett, Joseph Boone Muhlestein, Kurt R. Jensen, Diane Marshall, Tami L. Bair, Heidi T. May, John F. Carlquist, Matthew Hegewald, Stacey Knight, Viet T. Le, T. Jared Bunch, Donald L. Lappé, Jeffrey L. Anderson, Kirk U. Knowlton
BACKGROUND. Human papillomavirus–related (HPV-related) oropharyngeal squamous cell carcinomas (OPSCCs) have an excellent response rate to platinum-based chemoradiotherapy. Genomic differences between primary HPV-related OPSCCs that do or do not recur are unknown. Furthermore, it is unclear if HPV-related OPSCCs that recur share a genomic landscape with HPV-negative head and neck cancers (HNCs). METHODS. We utilized whole exome sequencing to analyze somatic nucleotide (SNVs) and copy number variants (CNVs) among a unique set of 51 primary HPV-related OPSCCs, including 35 that did not recur and 16 that recurred. We evaluated 12 metachronous recurrent OPSCCs (7 with paired primary OPSCCs) and 33 primary HPV-unrelated oral cavity and OPSCCs. RESULTS.KMT2D was the most frequently mutated gene among primary HPV-related OPSCCs (n = 51; 14%) and among metachronous recurrent OPSCCs (n = 12; 42%). Primary HPV-related OPSCCs that recurred shared a genomic landscape with primary HPV-related OPSCCs that did not recur. However, TSC2, BRIP1, NBN, and NFE2L2 mutations occurred in primary OPSCCs that recurred but not in those that did not recur. Moreover, primary HPV-related OPSCCs that recur harbor features of HPV-unrelated HNCs, notably including MAPK, JAK/STAT, and differentiation signaling pathway aberrations. Metachronous recurrent OPSCCs shared a genomic landscape with HPV-unrelated HNCs, including a high frequency of TP53, CASP8, FAT1, HLA-A, AJUBA, and NSD1 genomic alterations. CONCLUSION. Overall, primary HPV-related OPSCCs that recur share a genomic landscape with nonrecurrent OPSCCs. Metachronous recurrent OPSCCs share genomic features with HPV-negative HNCs. These data aim to guide future deescalation endeavors and functional experiments. FUNDING. This study is supported by the American Cancer Society (RSG TBG-123653), funding support for RAH (T32DC00018, Research Training in Otolaryngology, University of Washington), funds to EM from Seattle Translational Tumor Research (Fred Hutchinson Cancer Research Center), and center funds from the Fred Hutchinson Cancer Research Center to EM. UD is supported by the Department of Veterans Affairs, Biomedical Laboratory Research and Development (BLR&D), grant IO1-oo23456, and funds from the Pittsburgh Foundation and PNC Foundation.
R. Alex Harbison, Mark Kubik, Eric Q. Konnick, Qing Zhang, Seok-Geun Lee, Heuijoon Park, Jianan Zhang, Christopher S. Carlson, Chu Chen, Stephen M. Schwartz, Cristina P. Rodriguez, Umamaheswar Duvvuri, Eduardo Méndez
BACKGROUND. Immune checkpoint inhibitors provide significant clinical benefit to a subset of patients, but novel prognostic markers are needed to predict which patients will respond. This study was initiated to determine if features of patient T cell repertoires could provide insights into the mechanisms of immunotherapy, while also predicting outcomes. METHODS. We examined T cell receptor (TCR) repertoires in peripheral blood of 25 metastatic pancreatic cancer patients treated with ipilimumab with or without GVAX (a pancreatic cancer vaccine), as well as peripheral blood and tumor biopsies from 32 patients treated with GVAX and mesothelin-expressing Listeria monocytogenes with or without nivolumab. Statistics from these repertoires were then tested for their association with clinical response and treatment group. RESULTS. We demonstrate that, first, the majority of patients receiving these treatments experience a net diversification of their peripheral TCR repertoires. Second, patients receiving ipilimumab experienced larger changes in their repertoires, especially in combination with GVAX. Finally, both a low baseline clonality and a high number of expanded clones following treatment were associated with significantly longer survival in patients who received ipilimumab but not in patients receiving nivolumab. CONCLUSIONS. We show that these therapies have measurably different effects on the peripheral repertoire, consistent with their mechanisms of action, and demonstrate the potential for TCR repertoire profiling to serve as a biomarker of clinical response in pancreatic cancer patients receiving immunotherapy. In addition, our results suggest testing sequential administration of anti–CTLA-4 and anti–PD-1 antibodies to achieve optimal therapeutic benefit. TRIAL REGISTRATION. Samples used in this study were collected from the NCT00836407 and NCT02243371 clinical trials. FUNDING. Research supported by a Stand Up To Cancer Lustgarten Foundation Pancreatic Cancer Convergence Dream Team Translational Research grant (SU2C-AACR-DT14-14). Stand Up To Cancer is a program of the Entertainment Industry Foundation administered by the American Association for Cancer Research (AACR). Additional clinical trial funding was provided by AACR-Pancreatic Cancer Action Network Research Acceleration Network grant (14-90-25-LE), NCI SPORE in GI Cancer (CA062924), Quick-Trials for Novel Cancer Therapies: Exploratory Grants (R21CA126058-01A2), and the US Food and Drug Administration (R01FD004819). Research collaboration and financial support were provided by Adaptive Biotechnologies.
Alexander C. Hopkins, Mark Yarchoan, Jennifer N. Durham, Erik C. Yusko, Julie A. Rytlewski, Harlan S. Robins, Daniel A. Laheru, Dung T. Le, Eric R. Lutz, Elizabeth M. Jaffee
BACKGROUND. The prevalence of chronic kidney disease (CKD) is increasing worldwide. The identification of factors contributing to its progression is important for designing preventive measures. Previous studies have suggested that chronically high vasopressin is deleterious to renal function. Here, we evaluated the association of plasma copeptin, a surrogate of vasopressin, with the incidence of CKD in the general population. METHODS. We studied 3 European cohorts: DESIR (n = 5,047; France), MDCS-CC (n = 3,643; Sweden), and PREVEND (n = 7,684; the Netherlands). Median follow-up was 8.5, 16.5, and 11.3 years, respectively. Pooled data were analyzed at an individual level for 4 endpoints during follow-up: incidence of stage 3 CKD (estimated glomerular filtration rate [eGFR] < 60 ml/min/1.73 m2); the KDIGO criterion “certain drop in eGFR”; rapid kidney function decline (eGFR slope steeper than –3 ml/min/1.73 m2/yr); and incidence of microalbuminuria. RESULTS. The upper tertile of plasma copeptin was significantly and independently associated with a 49% higher risk for stage 3 CKD (P < 0.0001); a 64% higher risk for kidney function decline, as defined by the KDIGO criterion (P < 0.0001); a 79% higher risk for rapid kidney function decline (P < 0.0001); and a 24% higher risk for microalbuminuria (P = 0.008). CONCLUSIONS. High copeptin levels are associated with the development and the progression of CKD in the general population. Intervention studies are needed to assess the potential beneficial effect on kidney health in the general population of reducing vasopressin secretion or action. FUNDING. INSERM and Danone Research Centre for Specialized Nutrition.
Ray El Boustany, Irina Tasevska, Esther Meijer, Lyanne M. Kieneker, Sofia Enhörning, Guillaume Lefèvre, Kamel Mohammedi, Michel Marre, Frédéric Fumeron, Beverley Balkau, Nadine Bouby, Lise Bankir, Stephan J.L. Bakker, Ronan Roussel, Olle Melander, Ron T. Gansevoort, Gilberto Velho
BACKGROUND. Noroviruses are the leading cause of epidemic acute gastroenteritis and foodborne diarrheal disease in humans. However, there are no approved vaccines for noroviruses. Potential correlates of protection identified through human challenge studies include mucosal IgA, memory B cells, and serum-blocking antibody titers (BT50). METHODS. We conducted a single-site, randomized, double-blind, placebo-controlled clinical trial of an oral norovirus vaccine to determine safety and immunogenicity. This tablet vaccine is comprised of a nonreplicating adenovirus-based vector expressing the VP1 gene from the GI.1 norovirus strain and a double-stranded RNA adjuvant. Sixty-six adult subjects meeting inclusion/exclusion criteria were randomized 2:1 to receive a single vaccine dose or placebo, respectively. Immunogenicity was primarily assessed by serum BT50. Additional outcomes included serum ELISA titers, fecal and saliva antibody titers, memory and antibody-secreting cell (ASC) frequency, and B cell phenotyping. RESULTS. The vaccine was well-tolerated, with no dose-limiting toxicities. Adverse events were mild or moderate. The primary immunological endpoint (increase in BT50 titers) was met in the high-dose group (P = 0.0003), with 78% showing a ≥2-fold rise in titers after a single immunization. Vaccine recipients also developed mucosally primed VP1-specific circulating ASCs, IgA+ memory B cells expressing gut-homing receptor (α4β7), and fecal IgA, indicating substantial and local responses potentially relevant to prevent norovirus infection. CONCLUSION. This oral norovirus vaccine was well-tolerated and generated substantial immune responses, including systemic and mucosal antibodies as well as memory IgA/IgG. These results are a major step forward for the development of a safe and immunogenic oral norovirus vaccine. TRIAL REGISTRATION. ClinicalTrials.gov NCT02868073. FUNDING. Vaxart.
Leesun Kim, David Liebowitz, Karen Lin, Kassandra Kasparek, Marcela F. Pasetti, Shaily J. Garg, Keith Gottlieb, George Trager, Sean N. Tucker
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