Synchro-PASEF Allows Precursor-Specific Fragment Ion Extraction and Interference Removal in Data-Independent Acquisition

Data-independent acquisition (DIA) methods have become increasingly popular in mass spectrometry–based proteomics because they enable continuous acquisition of fragment spectra for all precursors simultaneously. However, these advantages come with the challenge of correctly reconstructing the precursor–fragment relationships in these highly convoluted spectra for reliable identification and quantification. Here, we introduce a scan mode for the combination of trapped ion mobility spectrometry with parallel accumulation—serial fragmentation (PASEF) that seamlessly and continuously follows the natural shape of the ion cloud in ion mobility and peptide precursor mass dimensions. Termed synchro-PASEF, it increases the detected fragment ion current several-fold at sub-second cycle times. Consecutive quadrupole selection windows move synchronously through the mass and ion mobility range. In this process, the quadrupole slices through the peptide precursors, which separates fragment ion signals of each precursor into adjacent synchro-PASEF scans. This precisely defines precursor–fragment relationships in ion mobility and mass dimensions and effectively deconvolutes the DIA fragment space. Importantly, the partitioned parts of the fragment ion transitions provide a further dimension of specificity via a lock-and-key mechanism. This is also advantageous for quantification, where signals from interfering precursors in the DIA selection window do not affect all partitions of the fragment ion, allowing to retain only the specific parts for quantification. Overall, we establish the defining features of synchro-PASEF and explore its potential for proteomic analyses.     

Improving Statistical Certainty of Glycosylation Similarity between Influenza A Virus Variants Using Data-Independent Acquisition Mass Spectrometry

Amino acid sequences of immunodominant domains of hemagglutinin (HA) on the surface of influenza A virus (IAV) evolve rapidly, producing viral variants. HA mediates receptor recognition, binding and cell entry, and serves as the target for IAV vaccines. Glycosylation, a post-translational modification that places large branched polysaccharide molecules on proteins, can modulate the function of HA and shield antigenic regions allowing for viral evasion from immune responses. Our previous work showed that subtle changes in the HA protein sequence can have a measurable change in glycosylation. Thus, being able to quantitatively measure glycosylation changes in variants is critical for understanding how HA function may change throughout viral evolution. Moreover, understanding quantitatively how the choice of viral expression systems affects glycosylation can help in the process of vaccine design and manufacture. Although IAV vaccines are most commonly expressed in chicken eggs, cell-based vaccines have many advantages, and the adoption of more cell-based vaccines would be an important step in mitigating seasonal influenza and protecting against future pandemics. Here, we have investigated the use of data-independent acquisition (DIA) mass spectrometry for quantitative glycoproteomics. We found that DIA improved the sensitivity of glycopeptide detection for four variants of A/Switzerland/9715293/2013 (H3N2): WT and mutant, each expressed in embryonated chicken eggs and Madin–Darby canine kidney cells. We used the Tanimoto similarity metric to quantify changes in glycosylation between WT and mutant and between egg-expressed and cell-expressed virus. Our DIA site-specific glycosylation similarity comparison of WT and mutant expressed in eggs confirmed our previous analysis while achieving greater depth of coverage. We found that sequence variations and changing viral expression systems affected distinct glycosylation sites of HA. Our methods can be applied to track glycosylation changes in circulating IAV variants to bolster genomic surveillance already being done, for a more complete understanding of IAV evolution.     

Differential Proteome and Interactome Analysis Reveal the Basis of Pleiotropy Associated With the Histidine Methyltransferase Hpm1p

The methylation of histidine is a post-translational modification whose function is poorly understood. Methyltransferase histidine protein methyltransferase 1 (Hpm1p) monomethylates H243 in the ribosomal protein Rpl3p and represents the only known histidine methyltransferase in Saccharomyces cerevisiae. Interestingly, the hpm1 deletion strain is highly pleiotropic, with many extraribosomal phenotypes including improved growth rates in alternative carbon sources. Here, we investigate how the loss of histidine methyltransferase Hpm1p results in diverse phenotypes, through use of targeted mass spectrometry (MS), growth assays, quantitative proteomics, and differential crosslinking MS. We confirmed the localization and stoichiometry of the H243 methylation site, found unreported sensitivities of Δhpm1 yeast to nonribosomal stressors, and identified differentially abundant proteins upon hpm1 knockout with clear links to the coordination of sugar metabolism. We adapted the emerging technique of quantitative large-scale stable isotope labeling of amino acids in cell culture crosslinking MS for yeast, which resulted in the identification of 1267 unique in vivo lysine–lysine crosslinks. By reproducibly monitoring over 350 of these in WT and Δhpm1, we detected changes to protein structure or protein–protein interactions in the ribosome, membrane proteins, chromatin, and mitochondria. Importantly, these occurred independently of changes in protein abundance and could explain a number of phenotypes of Δhpm1, not addressed by expression analysis. Further to this, some phenotypes were predicted solely from changes in protein structure or interactions and could be validated by orthogonal techniques. Taken together, these studies reveal a broad role for Hpm1p in yeast and illustrate how crosslinking MS will be an essential tool for understanding complex phenotypes.     

Experience of Ectopic Adrenocorticotropin Syndrome: 88 Cases With Identified Causes

ObjectiveEctopic adrenocorticotropic hormone syndrome (EAS) is a rare cause of Cushing's syndrome and diagnosis and management remain challenging. The aim of this study was to present the clinical spectrum of a group of EAS cases in a single center to explore better management strategies.MethodsA retrospective study was conducted to identify 88 confirmed EAS cases at our hospital from 1984 to 2019. The clinical, biochemical, imaging, and pathological features were analyzed.ResultsOf the 88 eligible patients with EAS, 38 (43.2%) cases of pulmonary neuroendocrine tumors (NETs) and a larger number of thymic/mediastinal NETs (29 cases, 33%) were identified. The clinical and biological features of EAS and Cushing's disease overlapped but were more severe in EAS. Inferior petrosal sinus sampling (97.4%) and computed tomography (85.4%) provided the highest positive diagnostic accuracy. Computed tomography is also a useful tool to identify tumors in chest cavity compared with nonchest lesions (91.2% vs 57.1%). Although a greater tumor size (4.54 cm vs 1.44 cm) and higher rate of insuppressible high-dose dexamethasone suppression test (83.3% vs 51.5%) were found in thymic/mediastinum NETs than in pulmonary NETs, the level of hormone production had no difference.ConclusionEAS had more common and severe clinical presentations than Cushing's disease, and multiple imaging approaches are required for reliable diagnosis. A higher proportion of thymic/mediastinal NETs was found in our study. For patients without a certain tumor source, long-term follow-up and further evaluations are needed.     

Tissue-Characteristic Expression of Mouse Proteome

The mouse is a valuable model organism for biomedical research. Here, we established a comprehensive spectral library and the data-independent acquisition–based quantitative proteome maps for 41 mouse organs, including some rarely reported organs such as the cornea, retina, and nine paired organs. The mouse spectral library contained 178,304 peptides from 12,320 proteins, including 1678 proteins not reported in previous mouse spectral libraries. Our data suggested that organs from the nervous system and immune system expressed the most distinct proteome compared with other organs. We also found characteristic protein expression of immune-privileged organs, which may help understanding possible immune rejection after organ transplantation. Each tissue type expressed characteristic high-abundance proteins related to its physiological functions. We also uncovered some tissue-specific proteins which have not been reported previously. The testis expressed highest number of tissue-specific proteins. By comparison of nine paired organs including kidneys, testes, and adrenal glands, we found left organs exhibited higher levels of antioxidant enzymes. We also observed expression asymmetry for proteins related to the apoptotic process, tumor suppression, and organ functions between the left and right sides. This study provides a comprehensive spectral library and a quantitative proteome resource for mouse studies.     

New Views of Old Proteins: Clarifying the Enigmatic Proteome

All human diseases involve proteins, yet our current tools to characterize and quantify them are limited. To better elucidate proteins across space, time, and molecular composition, we provide a >10 years of projection for technologies to meet the challenges that protein biology presents. With a broad perspective, we discuss grand opportunities to transition the science of proteomics into a more propulsive enterprise. Extrapolating recent trends, we describe a next generation of approaches to define, quantify, and visualize the multiple dimensions of the proteome, thereby transforming our understanding and interactions with human disease in the coming decade.     

Characteristics of Diabetic and Nondiabetic Patients With Thyroid Eye Disease in the United States: A Claims-Based Analysis

ObjectiveThyroid eye disease (TED) is a debilitating autoimmune disease characterized by ocular and periorbital tissue inflammation, proptosis, and visual impairment. The known risk factors for TED include radioactive iodine therapy, female sex, and smoking. The risk factors for severe TED include hyperthyroidism, male sex, smoking, and diabetes; however, little is known about how diabetes mellitus (DM) influences TED. This claims-based analysis examined TED characteristics in patients with and without diabetes.MethodsSymphony database (2010-2015 U.S. claims) was mined for patients with ≥1 Graves’ disease diagnosis code and ≥1 TED-associated eye code, including proptosis, strabismus, diplopia, lid retraction, exposure keratoconjunctivitis, and optic neuropathy (ON). DM status was determined based on type 1 or type 2 diabetes coding. Sight-threatening TED was defined as ≥1 ON or exposure keratoconjunctivitis code.ResultsA total of 51 220 patients were identified. Of them, 2618 (5.1%) and 12 846 (25.1%) had type 1 and type 2 DM, respectively. Patients with and without DM had similar characteristics, but patients with DM were more often men (type 1: 30.3%, type 2: 28.7% vs no DM: 20.5%; both P < .001) and older at the first TED code. In patients with DM, strabismus (25.4%, 22.6% vs 19.9%) and diplopia (38.6%, 37.9% vs 29.9%) occurred more often but proptosis occurred less often (42.3%, 46.3% vs 58.5%; all P < .001). Sight-threatening TED occurred more often in patients with DM because of higher ON rates.ConclusionPatients with TED and DM may have more extraocular muscle involvement. Furthermore, the higher prevalence of severe TED stemmed from higher ON rates, possibly associated with diabetes-related vasculopathies. These hypothesis-generating data warrant further exploration.     

Effect of Environmental Temperatures on Proteome Composition of Salmonella enterica Serovar Typhimurium

Salmonella enterica serovar Typhimurium (STM) is a major cause of gastroenteritis and transmitted by consumption of contaminated food. STM is associated to food originating from animals (pork, chicken, eggs) or plants (vegetables, fruits, nuts, and herbs). Infection of warm-blooded mammalian hosts by STM and the underlying complex regulatory network of virulence gene expression depend on various environmental conditions encountered in hosts. However, less is known about the proteome and possible regulatory networks for gene expression of STM outside the preferred host. Nutritional limitations and changes in temperature are the most obvious stresses outside the native host. Thus, we analyzed the proteome profile of STM grown in rich medium (LB medium) or minimal medium (PCN medium) at temperatures ranging from 8 °C to 37 °C. LB medium mimics the nutritional rich environment inside the host, whereas minimal PCN medium represents nutritional limitations outside the host, found during growth of fresh produce (field conditions). Further, the range of temperatures analyzed reflects conditions within natural hosts (37 °C), room temperature (20 °C), during growth under agricultural conditions (16 °C and 12 °C), and during food storage (8 °C). Implications of altered nutrient availability and growth temperature on STM proteomes were analyzed by HPLC/MS-MS and label-free quantification. Our study provides first insights into the complex adaptation of STM to various environmental temperatures, which allows STM not only to infect mammalian hosts but also to enter new infection routes that have been poorly studied so far. With the present dataset, global virulence factors, their impact on infection routes, and potential anti-infective strategies can now be investigated in detail. Especially, we were able to demonstrate functional flagella at 12 °C growth temperature for STM with an altered motility behavior.     

Echocardiographic Findings in Patients With Normocalcemic Primary Hyperparathyroidism Compared With Findings in Hypercalcemic Primary Hyperparathyroid Patients and Control Subjects

ObjectiveThere are no data regarding echocardiographic parameters in patients with normocalcemic primary hyperparathyroidism (NCPHPT). We compared the echocardiographic findings in postmenopausal women with NCPHPT with those in patients with hypercalcemic primary hyperparathyroidism (PHPT) and controls.MethodsSeventeen consecutive Caucasian postmenopausal women with NCPHPT were compared with 20 women with hypercalcemic PHPT and 20 controls. Obesity, diabetes, kidney failure, and previous cardiovascular diseases were considered exclusion criteria. Each patient underwent biochemical evaluation, bone mineral density scan, and echocardiographic measurements. Patients with parathyroid disorders underwent kidney ultrasound evaluation.ResultsPatients with PHPT had significantly higher mean total serum calcium, ionized calcium, 24-hour urinary calcium, and parathyroid hormone and lower mean phosphorus levels compared with those in the controls (all P < .05). The only differences between patients with NCPHPT and PHPT were significantly lower mean total serum calcium, ionized calcium, and 24-hour urinary calcium and higher phosphorus levels in patients with NCPHPT (all P < .05). The only biochemical difference between patients with NCPHPT and the controls was a higher level of mean parathyroid hormone in patients with NCPHPT. There were no differences in cardiovascular risk factors between patients with NCPHPT and PHPT and the controls. Hypertension was the most frequent cardiovascular risk factor, diagnosed in 65% of patients with PHPT. This high prevalence was not statistically significant compared with that observed in patients with NCPHPT (59%) and in the controls (30%). Echocardiography parameters were not different between patients with NCPHPT and PHPT and the controls when subdivided according to the presence of hypertension (ANOVA followed by Bonferroni correction).ConclusionIn a population with a low cardiovascular risk, we found no differences in cardiovascular risk factors and echocardiographic parameters between patients with NCPHPT and PHPT and the controls.     

New Insights on Effects of Glucocorticoids in Patients With SARS-CoV-2 Infection

ObjectiveSince January 2020, the highly contagious novel coronavirus SARS-CoV-2 has caused a global pandemic. Severe COVID-19 leads to a massive release of proinflammatory mediators, leading to diffuse damage to the lung parenchyma, and the development of acute respiratory distress syndrome. Treatment with the highly potent glucocorticoid (GC) dexamethasone was found to be effective in reducing mortality in severely affected patients.MethodsTo review the effects of glucocorticoids in the context of COVID-19 we performed a literature search in the PubMed database using the terms COVID-19 and glucocorticoid treatment. We identified 1429 article publications related to COVID-19 and glucocorticoid published from 1.1.2020 to the present including 238 review articles and 36 Randomized Controlled Trials. From these studies, we retrieved 13 Randomized Controlled Trials and 86 review articles that were relevant to our review topics. We focused on the recent literature dealing with glucocorticoid metabolism in critically ill patients and investigating the effects of glucocorticoid therapy on the immune system in COVID-19 patients with severe lung injury.ResultsIn our review, we have discussed the regulation of the hypothalamic-pituitary-adrenal axis in patients with critical illness, selection of a specific GC for critical illness-related GC insufficiency, and recent studies that investigated hypothalamic-pituitary-adrenal dysfunction in patients with COVID-19. We have also addressed the specific activation of the immune system with chronic endogenous glucocorticoid excess, as seen in patients with Cushing syndrome, and, finally, we have discussed immune activation due to coronavirus infection and the possible mechanisms leading to improved outcomes in patients with COVID-19 treated with GCs.ConclusionFor clinical endocrinologists prescribing GCs for their patients, a precise understanding of both the molecular- and cellular-level mechanisms of endogenous and exogenous GCs is imperative, including timing of administration, dosage, duration of treatment, and specific formulations of GCs.     

Immunopeptidomic Analyses of Colorectal Cancers With and Without Microsatellite Instability

Colorectal cancer is the second leading cause of cancer death worldwide, and the incidence of this disease is expected to increase as global socioeconomic changes occur. Immune checkpoint inhibition therapy is effective in treating a minority of colorectal cancer tumors; however, microsatellite stable tumors do not respond well to this treatment. Emerging cancer immunotherapeutic strategies aim to activate a cytotoxic T cell response against tumor-specific antigens, presented exclusively at the cell surface of cancer cells. These antigens are rare and are most effectively identified with a mass spectrometry–based approach, which allows the direct sampling and sequencing of these peptides. Although the few tumor-specific antigens identified to date are derived from coding regions of the genome, recent findings indicate that a large proportion of tumor-specific antigens originate from allegedly noncoding regions. Here, we employed a novel proteogenomic approach to identify tumor antigens in a collection of colorectal cancer–derived cell lines and biopsy samples consisting of matched tumor and normal adjacent tissue. The generation of personalized cancer databases paired with mass spectrometry analyses permitted the identification of more than 30,000 unique MHC I–associated peptides. We identified 19 tumor-specific antigens in both microsatellite stable and unstable tumors, over two-thirds of which were derived from noncoding regions. Many of these peptides were derived from source genes known to be involved in colorectal cancer progression, suggesting that antigens from these genes could have therapeutic potential in a wide range of tumors. These findings could benefit the development of T cell–based vaccines, in which T cells are primed against these antigens to target and eradicate tumors. Such a vaccine could be used in tandem with existing immune checkpoint inhibition therapies, to bridge the gap in treatment efficacy across subtypes of colorectal cancer with varying prognoses. Data are available via ProteomeXchange with identifier PXD028309.     

Association of Early Pregnancy Free and Total Triiodothyronine With the Subsequent Risk of Gestational Diabetes Mellitus

ObjectiveTo estimate the association of free triiodothyronine (FT3) and total triiodothyronine (TT3) in early pregnancy and subsequent gestational diabetes mellitus (GDM) risk and define appropriate TT3 thresholds for GDM screening.MethodsThis investigation is a hospital-based cohort study of pregnant women submitted to a universal thyroid function test before 24 weeks of gestation. GDM was diagnosed according to a 75-g oral glucose tolerance test. The association of maternal high FT3 and TT3 levels in early pregnancy with the risk of GDM was estimated using logistic regression. The potential nonlinear association was probed by the restricted cubic spline curve method.ResultsA total of 27 184 pregnant women and 3073 GDM cases were included in the analysis. FT3 and TT3 were associated with an increased subsequent risk of GDM in a nonlinear fashion. The adjusted odds ratios were 1.59 (95% confidence interval, 1.50-1.68) and 2.80 (95% confidence interval, 2.46-3.18) for FT3 and TT3 continuous levels, respectively. Associations were strong in euthyroid women, showed heterogeneity in women with mild thyroid dysfunction, and lacked in patients with overt hypothyroidism and hyperthyroidism. The TT3 thresholds of 1.5 and 2.0 ng/mL between 7 and 12 weeks of gestation and 1.6 and 2.1 ng/mL for 13 to 23 weeks of gestation effectively distinguished the subsequent risk of GDM.ConclusionThe increased FT3 and TT3 levels in early pregnancy were associated with a subsequent higher risk of GDM. These findings provide measures for early detection and potential prevention of GDM.     

Seated Saline Suppression Test Is Comparable With Captopril Challenge Test for the Diagnosis of Primary Aldosteronism: A Prospective Study

ObjectiveThe saline suppression test (SST) and captopril challenge test (CCT) are commonly used confirmatory tests for primary aldosteronism (PA). Seated SST (SSST) has been reported to be superior to recumbent SST. Whether SSST is better than CCT remains unclear. We aimed to compare the diagnostic accuracy of SSST and CCT in a prospective study.MethodsHypertensive patients at a high risk of PA were consecutively included. Patients with an aldosterone-renin ratio of ≥1.0 ng/dL/μIU/mL were asked to complete SSST, CCT, and the fludrocortisone suppression test (FST). Using FST as a reference standard (plasma aldosterone concentration [PAC] post FST ≥ 6.0 ng/dL), area under the receiver-operating characteristic curve (AUC), sensitivity, and specificity of SSST and CCT were calculated, and multiple regression analyses were performed to identify potential factors leading to false diagnosis.ResultsA total of 196 patients diagnosed with PA and 73 with essential hypertension completed the study. Using PAC post SSST and PAC post CCT to confirm PA, SSST and CCT had comparable AUCs (AUC_SSST 0.87 [95% CI 0.82-0.91] vs AUC_CCT 0.88 [0.83-0.95], P = .646). When PAC post SSST and post CCT were set at 8.5 and 11 ng/dL, respectively, the sensitivity and specificity of SSST (0.72 [0.65, 0.78] and 0.86 [0.76, 0.93]) and CCT (0.73 [0.67, 0.80] and 0.85 [0.75, 0.92]) were not significantly different. In the multiple regression analyses, 1-SD increment of sodium intake resulted in a 40% lower risk of false diagnosis with SSST.ConclusionSSST and CCT have comparable diagnostic accuracy. Insufficient sodium intake decreases the diagnostic efficiency of SSST but not of CCT. Since CCT is simpler and cheaper, it is preferred over SSST.     

Functional Diversity and Evolution of the Drosophila Sperm Proteome

Spermatozoa are central to fertilization and the evolutionary fitness of sexually reproducing organisms. As such, a deeper understanding of sperm proteomes (and associated reproductive tissues) has proven critical to the advancement of the fields of sexual selection and reproductive biology. Due to their extraordinary complexity, proteome depth-of-coverage is dependent on advancements in technology and related bioinformatics, both of which have made significant advancements in the decade since the last Drosophila sperm proteome was published. Here, we provide an updated version of the Drosophila melanogaster sperm proteome (DmSP3) using improved separation and detection methods and an updated genome annotation. Combined with previous versions of the sperm proteome, the DmSP3 contains a total of 3176 proteins, and we provide the first label-free quantitation of the sperm proteome for 2125 proteins. The top 20 most abundant proteins included the structural elements α- and β-tubulins and sperm leucyl-aminopeptidases. Both gene content and protein abundance were significantly reduced on the X chromosome, consistent with prior genomic studies of X chromosome evolution. We identified 9 of the 16 Y-linked proteins, including known testis-specific male fertility factors. We also identified almost one-half of known Drosophila ribosomal proteins in the DmSP3. The role of this subset of ribosomal proteins in sperm is unknown. Surprisingly, our expanded sperm proteome also identified 122 seminal fluid proteins (Sfps), proteins originally identified in the accessory glands. We show that a significant fraction of ‘sperm-associated Sfps’ are recalcitrant to concentrated salt and detergent treatments, suggesting this subclass of Sfps are expressed in testes and may have additional functions in sperm, per se. Overall, our results add to a growing landscape of both sperm and seminal fluid protein biology and in particular provides quantitative evidence at the protein level for prior findings supporting the meiotic sex-chromosome inactivation model for male-specific gene and X chromosome evolution.     

Risk Factors of Thyroid Eye Disease

ObjectiveTo examine risk factors that might be associated with thyroid eye disease (TED) in patients with Graves’ disease (GD), which may guide physicians in the prevention and management of TED.MethodsMedline and Embase were searched for articles discussing risk factors of TED. Comparisons were made between GD patients with and without TED, and between active and inactive TED GD patients. Weighted mean differences (WMDs) and odds ratios (ORs) were determined for continuous and dichotomous outcomes, respectively. Results were pooled with random effects using the DerSimonian and Laird model.ResultsFifty-six articles were included in the analysis. Smoking, inclusive of current and previous smoking status, was a significant risk factor for TED (OR: 2.401; CI: 1.958-2.945; P < .001). Statistical significance was found upon meta-regression between male sex and the odds of smoking and TED (β = 1.195; SE = 0.436; P = .013). Other risk factors were also examined, and patients with TED were significantly older than those without TED (WMD: 1.350; CI: 0.328-2.372; P = .010). While both age (WMD: 5.546; CI: 3.075-8.017; P < .001) and male sex (OR: 1.819; CI: 1.178-2.808; P = .007) were found to be significant risk factors for active TED patients compared to inactive TED patients, no statistical significance was found for family history, thyroid status, cholesterol levels, or body mass index.ConclusionFactors such as smoking, sex, and age predispose GD patients to TED, and TED patients to active TED. A targeted approach in the management of GD and TED is required to reduce the modifiable risk factor of smoking.     

Hypoxia Is a Dominant Remodeler of the Effector T Cell Surface Proteome Relative to Activation and Regulatory T Cell Suppression

Immunosuppressive factors in the tumor microenvironment (TME) impair T cell function and limit the antitumor immune response. T cell surface receptors and surface proteins that influence interactions and function in the TME are proven targets for cancer immunotherapy. However, how the entire surface proteome remodels in primary human T cells in response to specific suppressive factors in the TME remains to be broadly and systematically characterized. Here, using a reductionist cell culture approach with primary human T cells and stable isotopic labeling with amino acids in cell culture–based quantitative cell surface capture glycoproteomics, we examined how two immunosuppressive TME factors, regulatory T cells (Tregs) and hypoxia, globally affect the activated CD8⁺ surface proteome (surfaceome). Surprisingly, coculturing primary CD8⁺ T cells with Tregs only modestly affected the CD8⁺ surfaceome but did partially reverse activation-induced surfaceomic changes. In contrast, hypoxia drastically altered the CD8⁺ surfaceome in a manner consistent with both metabolic reprogramming and induction of an immunosuppressed state. The CD4⁺ T cell surfaceome similarly responded to hypoxia, revealing a common hypoxia-induced surface receptor program. Our surfaceomics findings suggest that hypoxic environments create a challenge for T cell activation. These studies provide global insight into how Tregs and hypoxia remodel the T cell surfaceome and we believe represent a valuable resource to inform future therapeutic efforts to enhance T cell function.     

Long-Term Adverse Effects of Cigarette Smoking on the Incidence Risk of Metabolic Syndrome With a Dose-Response Relationship: Longitudinal Findings of the Korean Genome and Epidemiology Study Over 12 Years

ObjectiveTo investigate the association between the intensity and cumulative dose of cigarette smoking and incidence risk of metabolic syndrome (MetS) in a longitudinal prospective study over 12 years of follow-up.MethodsThis study included 3151 men aged 40 to 69 years from the Korean Genome and Epidemiology Study. MetS was defined as proposed by the Joint Interim Statement of the Circulation 2009 report. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) for incidence risk of MetS were calculated from 2 separate perspectives: (1) number of cigarettes smoked per day (intensity) and (2) total number of cigarettes smoked over a person’s lifetime (cumulative dose) using multiple logistic regression analyses.ResultsIn comparison with never smokers, the HRs (95% CIs) were 0.97 (0.78-1.21) for former smokers and 1.50 (1.07-2.01) with 0 to 9 cigarettes per day, 1.66 (1.34-2.06) with 10 to 19 cigarettes per day, and 1.75 (1.34-2.29) with ≥20 cigarettes per day for current smokers after adjusting for confounding variables. Similar positive dose-response relationships were also observed when the cumulative dose of cigarette smoking was categorized into former and current smokers, with subcategories of <20 and >20 pack-years (PYs). The HRs (95% CIs) were 0.99 (0.77-1.23) for <20 PYs and 0.99 (0.77-1.28) for ≥20 PYs for former smokers and 1.63 (1.32-2.02) for <20 PYs and 1.67 (1.30-2.14) for ≥20 PYs for current smokers after adjusting for the same covariables.ConclusionCigarette smoking intensity and cumulative dose were both found to be positively associated with the incidence risk of MetS in men.     

Hyperglycemia is Associated With Increased Mortality in Critically Ill Patients With COVID-19

ObjectiveTo explore the relationship between hyperglycemia in the presence and absence of diabetes mellitus (DM) and adverse outcomes in critically ill patients with coronavirus disease 2019 (COVID-19).MethodsThe study included 133 patients with COVID-19 admitted to an intensive care unit (ICU) at an urban academic quaternary-care center between March 10 and April 8, 2020. Patients were categorized based on the presence or absence of DM and early-onset hyperglycemia (EHG), defined as a blood glucose >180 mg/dL during the first 2 days after ICU admission. The primary outcome was 14-day all-cause in-hospital mortality; also examined were 60-day all-cause in-hospital mortality and the levels of C-reactive protein, interleukin 6, procalcitonin, and lactate.ResultsCompared to non-DM patients without EHG, non-DM patients with EHG exhibited higher adjusted hazard ratios (HRs) for mortality at 14 days (HR 7.51, CI 1.70-33.24) and 60 days (HR 6.97, CI 1.86-26.13). Non-DM patients with EHG also featured higher levels of median C-reactive protein (306.3 mg/L, P = .036), procalcitonin (1.26 ng/mL, P = .028), and lactate (2.2 mmol/L, P = .023).ConclusionAmong critically ill COVID-19 patients, those without DM with EHG were at greatest risk of 14-day and 60-day in-hospital mortality. Our study was limited by its retrospective design and relatively small cohort. However, our results suggest the combination of elevated glucose and lactate may identify a specific cohort of individuals at high risk for mortality from COVID-19. Glucose testing and control are important in individuals with COVID-19, even those without preexisting diabetes.