CaMKIIδ Met281/282 oxidation is not required for recovery of calcium transients during acidosis.

CaMKII is needed for the recovery of Ca2+ transients during acidosis but also mediates postacidic arrhythmias. CaMKIIδ can sustain its activity following Met281/282 oxidation. Increasing cytosolic Na+ during acidosis as well as postacidic pH normalization should result in prooxidant conditions within the cell favoring oxidative CaMKIIδ activation. We tested whether CaMKIIδ activation through Met281/282 oxidation is involved in recovery of Ca2+ transients during acidosis and promotes cellular arrhythmias post-acidosis. Single cardiac myocytes were isolated from a well-established mouse model in which CaMKIIδ was made resistant to oxidative activation by knock-in replacement of two oxidant-sensitive methionines (Met281/282) with valines (MM-VV). MM-VV myocytes were exposed to extracellular acidosis (pHo 6.5) and compared to wild type (WT) control cells. Full recovery of Ca2+ transients was observed in both WT and MM-VV cardiac myocytes during late-phase acidosis. This was associated with comparably enhanced sarcoplasmic reticulum Ca2+ load and preserved CaMKII specific phosphorylation of phospholamban at Thr17 in MM-VV myocytes. CaMKII was phosphorylated at Thr287, but not Met281/282 oxidized. In line with this, postacidic cellular arrhythmias occurred to a similar extent in WT and MM-VV cells, whereas inhibition of CaMKII using AIP completely prevented recovery of Ca2+ transients during acidosis and attenuated postacidic arrhythmias in MM-VV cells. Using genetically altered cardiomyocytes with cytosolic expression of redox-sensitive green fluorescent protein-2 coupled to glutaredoxin 1, we found that acidosis has a reductive effect within the cytosol of cardiac myocytes despite a significant acidosis-related increase in cytosolic Na+. Our study shows that activation of CaMKIIδ through Met281/282 oxidation is neither required for recovery of Ca2+ transients during acidosis nor relevant for postacidic arrhythmogenesis in isolated cardiac myocytes. Acidosis reduces the cytosolic glutathione redox state of isolated cardiac myocytes despite a significant increase in cytosolic Na+. Pharmacological inhibition of global CaMKII activity completely prevents recovery of Ca2+ transients and protects from postacidic arrhythmias in MM-VV myocytes, which confirms the relevance of CaMKII in the context of acidosis.NEW & NOTEWORTHY The current study shows that activation of CaMKIIδ through Met281/282 oxidation is neither required for CaMKII-dependent recovery of Ca2+ transients during acidosis nor relevant for the occurrence of postacidic cellular arrhythmias. Despite a usually prooxidant increase in cytosolic Na+, acidosis reduces the cytosolic glutathione redox state within cardiac myocytes. This novel finding suggests that oxidation of cytosolic proteins is less likely to occur during acidosis.

Inhibition of cardiac potassium currents by oxidation-activated protein kinase A contributes to early afterdepolarizations in the heart.

Reactive oxygen species (ROS) have been shown to prolong cardiac action potential duration resulting in afterdepolarizations, the cellular basis of triggered arrhythmias. As previously shown, protein kinase A type I (PKA I) is readily activated by oxidation of its regulatory subunits. However, the relevance of this mechanism of activation for cardiac pathophysiology is still elusive. In this study, we investigated the effects of oxidation-activated PKA I on cardiac electrophysiology. Ventricular cardiomyocytes were isolated from redox-dead PKA-RI Cys17Ser knock-in (KI) and wild-type (WT) mice and exposed to H2O2 (200 µmol/L) or vehicle (Veh) solution. In WT myocytes, exposure to H2O2 significantly increased oxidation of the regulatory subunit I (RI) and thus its dimerization (threefold increase in PKA RI dimer). Whole cell current clamp and voltage clamp were used to measure cardiac action potentials (APs), transient outward potassium current (Ito) and inward rectifying potassium current (IK1), respectively. In WT myocytes, H2O2 exposure significantly prolonged AP duration due to significantly decreased Ito and IK1 resulting in frequent early afterdepolarizations (EADs). Preincubation with the PKA-specific inhibitor Rp-8-Br-cAMPS (10 µmol/L) completely abolished the H2O2-dependent decrease in Ito and IK1 in WT myocytes. Intriguingly, H2O2 exposure did not prolong AP duration, nor did it decrease Ito, and only slightly enhanced EAD frequency in KI myocytes. Treatment of WT and KI cardiomyocytes with the late INa inhibitor TTX (1 µmol/L) completely abolished EAD formation. Our results suggest that redox-activated PKA may be important for H2O2-dependent arrhythmias and could be important for the development of specific antiarrhythmic drugs.NEW & NOTEWORTHY Oxidation-activated PKA type I inhibits transient outward potassium current (Ito) and inward rectifying potassium current (IK1) and contributes to ROS-induced APD prolongation as well as generation of early afterdepolarizations in murine ventricular cardiomyocytes.

Neutral Processes Dominate Microbial Community Assembly in Atlantic Salmon, Salmo salar.

In recent years, a wealth of studies has examined the relationships between a host and its microbiome across diverse taxa. Many studies characterize the host microbiome without considering the ecological processes that underpin microbiome assembly. In this study, the intestinal microbiota of Atlantic salmon, Salmo salar, sampled from farmed and wild environments was first characterized using 16S rRNA gene MiSeq sequencing analysis. We used neutral community models to determine the balance of stochastic and deterministic processes that underpin microbial community assembly and transfer across life cycle stage and between gut compartments. Across gut compartments in farmed fish, neutral models suggest that most microbes are transient with no evidence of adaptation to their environment. In wild fish, we found declining taxonomic and functional microbial community richness as fish mature through different life cycle stages. Alongside neutral community models applied to wild fish, we suggest that declining richness demonstrates an increasing role for the host in filtering microbial communities that is correlated with age. We found a limited subset of gut microflora adapted to the farmed and wild host environment among which Mycoplasma spp. are prominent. Our study reveals the ecological drivers underpinning community assembly in both farmed and wild Atlantic salmon and underlines the importance of understanding the role of stochastic processes, such as random drift and small migration rates in microbial community assembly, before considering any functional role of the gut microbes encountered.IMPORTANCE A growing number of studies have examined variation in the microbiome to determine the role in modulating host health, physiology, and ecology. However, the ecology of host microbial colonization is not fully understood and rarely tested. The continued increase in production of farmed Atlantic salmon, coupled with increased farmed-wild salmon interactions, has accentuated the need to unravel the potential adaptive function of the microbiome and to distinguish resident from transient gut microbes. Between gut compartments in a farmed system, we found a majority of operational taxonomic units (OTUs) that fit the neutral model, with Mycoplasma species among the key exceptions. In wild fish, deterministic processes account for more OTU differences across life stages than those observed across gut compartments. Unlike previous studies, our results make detailed comparisons between fish from wild and farmed environments, while also providing insight into the ecological processes underpinning microbial community assembly in this ecologically and economically important species.

The German CPU registry: Comparison of smokers and nonsmokers.

BACKGROUND: Chest pain is a major reason for admission to an internal emergency department, and smoking is a well-known risk factor for coronary artery disease (CAD) and acute coronary syndrome (ACS). The aim of this analysis is to illustrate the differences between smokers and nonsmokers presenting to German chest pain units (CPU) in regard to patient characteristics, CAD manifestation, treatment strategy, and prognosis. METHODS: From December 2008 to March 2014, 13,902 patients who had a complete 3­month follow-up were enrolled in the German CPU registry. The analysis comprised 5796 patients with ACS and documented smoking status. RESULTS: Of all the patients in the CPU registry, 35.2% were smokers. Compared with nonsmokers, they were 13.5 years younger (58.2 vs. 71.7 years, p < 0.001), predominantly men (77.1% vs. 65.2%, p < 0.001), and were more frequently diagnosed with single-vessel disease (32.1% vs. 25.2%) as well as ST-elevation myocardial infarction (STEMI; 23.8% vs. 15.5%, p < 0.001). Although the Global Registry of Acute Coronary Events (GRACE) Risk Score for hospital mortality was lower in the group of smokers (106.1 vs. 123.3, p < 0.001), we did not observe any differences in CPU death (0.4% vs. 0.4%, p = 0.69) and CPU major adverse cardiac event (MACE) rates (3.8% vs 2.9%, p = 0.073) between the groups. In the 3­month follow-up, we documented higher mortality rates in the nonsmoker group (1.9% vs. 2.9%, p = 0.035) in correlation with the GRACE Risk Score (80.3 vs. 105.2, p < 0.001). MACE rates were similar during the follow-up (3.1% vs. 4.1%, p = 0.065). CONCLUSION: Observations from the German CPU registry demonstrate that smoking is a strong predictor of acute CAD manifestation early in life, especially STEMI. In spite of a lower GRACE Risk Score and fewer comorbidities, smokers had a rate of hospital mortality similar to the older group of nonsmokers.

The novel CaMKII inhibitor GS-680 reduces diastolic SR Ca leak and prevents CaMKII-dependent pro-arrhythmic activity.

RATIONALE: Ca/calmodulin-dependent protein kinase II (CaMKII) was shown to increase diastolic sarcoplasmic reticulum (SR) Ca leak, which can result in delayed afterdepolarizations and triggered arrhythmias. Since increased CaMKII expression and activity has been mechanistically linked to arrhythmias in human heart failure (HF) and atrial fibrillation (AF), specific strategies aimed at CaMKII inhibition may have therapeutic potential. OBJECTIVE: We tested the antiarrhythmic and inotropic effects of a novel selective and ATP-competitive CaMKII inhibitor (GS-680). METHODS AND RESULTS: Trabeculae were isolated from right atrial appendage biopsies of patients undergoing cardiac surgery. Premature atrial contractions (PACs) were induced by stimulation with isoproterenol (ISO, 100 nM) at increased [Ca]o (3.5 mM). Interestingly, compared to vehicle, PACs were significantly inhibited by exposure to GS-680 (at 100 and 300 nM). GS-680 also significantly decreased early and delayed afterdepolarizations in isolated human atrial myocytes. Moreover, GS-680 (at 100 or 300 nM) significantly inhibited diastolic SR Ca leak, measured as frequency of spontaneous SR Ca release events (Ca sparks) in isolated human atrial myocytes (Fluo-4 loaded) similar to the well-established peptide CaMKII inhibitor AIP. In accordance, GS-680 significantly reduced CaMKII autophosphorylation (Western blot) but enhanced developed tension after 10 or 30 s pause of electrical stimulation (post-rest behavior). Surprisingly, we found a strong negative inotropic effect of GS-680 in atrial trabeculae at 1 Hz stimulation rate, which was not observed at 4 Hz and abolished by beta-adrenergic stimulation. In contrast, GS-680 did not impair systolic force of isolated ventricular trabeculae from explanted hearts of heart transplant recipients at 1 Hz, blunted the negative force-frequency relationship (1-3 Hz) and significantly increased the Ca transient amplitude. CONCLUSION: The novel ATP-competitive and selective CaMKII inhibitor GS-680 inhibits pro-arrhythmic activity in human atrium and improves contractility in failing human ventricle, which may have therapeutic implications.

CaRMeN: a tool for analysing and deriving kinetics in the real world.

This paper presents the concepts of an open software tool (CaRMeN) that can be used to rapidly analyse and derive models, in particular chemical kinetics. The software automates the workflow of comparing model vs. experiment, which must currently be done manually and is thus a time-consuming and error-prone task. The capabilities of the software are illustrated through a case study. Experimental data for the conversion of methane over rhodium catalysts in a wide range of conditions and experimental setups are numerically simulated using five different mechanisms from the literature. The applicability of the mechanisms as well as differences between flow and diffusion models are evaluated. The results show that no single mechanism reliably predicts the chemical conversions of all of the experiments. Although the software was initially developed for chemical kinetics applications, it can also be extended to run any simulation code, and can therefore be applied in other scenarios.

Superallowed Gamow-Teller decay of the doubly magic nucleus 100Sn.

The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During ß(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the ß-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear ß-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.

First Measurement of Several ß-Delayed Neutron Emitting Isotopes Beyond N=126.

The ß-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with ß-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb, and Bi in the mass region N≳126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the ß-decay strength distribution. This provides important constraints on global theoretical models currently used in r-process nucleosynthesis.

Admission heart rate in relation to presentation and prognosis in patients with acute myocardial infarction. Treatment regimens in German chest pain units.

BACKGROUND: Higher heart rates on admission have been associated with poor outcomes in patients with an acute coronary syndrome in previous cohorts. Whether such a linear relationship still exists in contemporary high-level care is unclear. METHODS: Prospectively collected data from patients presenting with myocardial infarction (MI) in centers participating in the Chest Pain Unit (CPU) Registry between December 2008 and July 2014 were analyzed. Patients were classified according to their initial heart rate (I: < 50; II: 50-69; III: 70-89; IV: ≥ 90 bpm). A total of 6,168 patients out of 30,339 patients presenting to 38 centers were included in the study. RESULTS: Patients in group IV had more comorbidities, while patients in group I more often had a history of MI. Patients in the lowest heart rate group presented significantly earlier to the hospital (4 h 31 min vs. 7 h 37 min; p < 0.05) and had the highest rate of interventions. The overall survival after 3 months was significantly worse in group IV after adjusting for baseline variables. In the subgroup analysis, heart rate was a prognostic factor in the non-ST-segment elevation MI group but not in the ST-segment elevation MI group. The correlation between heart rate and major adverse cardiac events followed a J-shaped curve with worst outcomes in the lowest and highest heart rate groups. CONCLUSION: Patients admitted to a dedicated CPU with the diagnosis of MI and a heart rate > 90 bpm experience reduced survival at 3 months despite optimal treatment. Patients with bradycardia also seem to be at increased risk for cardiovascular events despite much earlier presentation and treatment.

[Extracorporeal pulmonary support procedures in intensive care medicine 2014]. / Extrakorporale Lungenunterstützungsverfahren in der Intensivmedizin 2014.

BACKGROUND: In recent years a rapid expansion of extracorporeal devices for support of severe lung failure has been witnessed. Systems for veno-venous extracorporeal membrane oxygenation (VV-ECMO) or for extracorporeal carbon dioxide elimination are distinguished depending on the indications. OBJECTIVES: The state of the art of extracorporeal lung support is presented with an overview of the different systems, the indications, efficiency and potential side effects. METHODS: By means of a selective literature research and based on personal experience, the principles and techniques, efficiency and potential side-effects of the new modalities are described. RESULTS: The VV-ECMO systems may be indicated in severe, refractory and predominantly hypoxemic lung failure (pAO2/FIO2 <80 mmHg). Both life-saving gas exchange and a reduction of ventilator-induced lung injury by means of a more protective ventilation can be achieved. Experienced centers can obtain survival rates of more than 60%. Either pumpless arterio-venous devices, also called interventional lung assist (ILA) or low-flow ECMO devices can be used for extracorporeal carbon dioxide elimination in refractory respiratory acidosis. Severe complications can occur with all modalities of extracorporeal support and have to be rapidly recognized and controlled. It must be pointed out that secure evidence based on prospective randomized studies is currently limited for all modalities. CONCLUSION: Modern extracorporeal lung support devices allow an effective extracorporeal gas exchange and have become an inherent component of intensive care treatment of critically ill patients. Due to potentially severe complications the use should be restricted to specialized centers with experience in the treatment of severe acute respiratory distress syndrome (ARDS).

Reduced preoperative serum choline esterase levels and fecal peritoneal contamination as potential predictors for the leakage of intestinal sutures after source control in secondary peritonitis.

BACKGROUND: The high rate of stoma placement during emergency laparotomy for secondary peritonitis is a paradigm in need of change in the current fast-track surgical setting. Despite growing evidence for the feasibility of primary bowel reconstruction in a peritonitic environment, little data substantiate a surgeons' choice between a stoma and an anastomosis. The aim of this retrospective analysis is to identify pre- and intraoperative parameters that predict the leakage risk for enteric sutures placed during source control surgery (SCS) for secondary peritonitis. METHODS: Between January 2014 and December 2020, 497 patients underwent SCS for secondary peritonitis, of whom 187 received a primary reconstruction of the lower gastro-intestinal tract without a diverting stoma. In 47 (25.1%) patients postoperative leakage of the enteric sutures was directly confirmed during revision surgery or by computed tomography. Quantifiable predictors of intestinal suture outcome were detected by multivariate analysis. RESULTS: Length of intensive care, in-hospital mortality and failure of release to the initial home environment were significantly higher in patients with enteric suture leakage following SCS compared to patients with intact anastomoses (p < 0.0001, p = 0.0026 and p =0.0009, respectively). Reduced serum choline esterase (sCHE) levels and a high extent of peritonitis were identified as independent risk factors for insufficiency of enteric sutures placed during emergency laparotomy. CONCLUSIONS: A preoperative sCHE < 4.5 kU/L and generalized fecal peritonitis associate with a significantly higher incidence of enteric suture insufficiency after primary reconstruction of the lower gastro-intestinal tract in a peritonitic abdomen. These parameters may guide surgeons when choosing the optimal surgical procedure in the emergency setting.

Enhanced Ca²+ influx through cardiac L-type Ca²+ channels maintains the systolic Ca²+ transient in early cardiac atrophy induced by mechanical unloading.

Cardiac atrophy as a consequence of mechanical unloading develops following exposure to microgravity or prolonged bed rest. It also plays a central role in the reverse remodelling induced by left ventricular unloading in patients with heart failure. Surprisingly, the intracellular Ca(2+) transients which are pivotal to electromechanical coupling and to cardiac plasticity were repeatedly found to remain unaffected in early cardiac atrophy. To elucidate the mechanisms underlying the preservation of the Ca(2+) transients, we investigated Ca(2+) cycling in cardiomyocytes from mechanically unloaded (heterotopic abdominal heart transplantation) and control (orthotopic) hearts in syngeneic Lewis rats. Following 2 weeks of unloading, sarcoplasmic reticulum (SR) Ca(2+) content was reduced by ~55 %. Atrophic cardiac myocytes also showed a much lower frequency of spontaneous diastolic Ca(2+) sparks and a diminished systolic Ca(2+) release, even though the expression of ryanodine receptors was increased by ~30 %. In contrast, current clamp recordings revealed prolonged action potentials in endocardial as well as epicardial myocytes which were associated with a two to fourfold higher sarcolemmal Ca(2+) influx under action potential clamp. In addition, Cav1.2 subunits which form the pore of L-type Ca(2+) channels (LTCC) were upregulated in atrophic myocardium. These data suggest that in early cardiac atrophy induced by mechanical unloading, an augmented sarcolemmal Ca(2+) influx through LTCC fully compensates for a reduced systolic SR Ca(2+) release to preserve the Ca(2+) transient. This interplay involves an electrophysiological remodelling as well as changes in the expression of cardiac ion channels.

[Pathophysiology of chronic myocardial ischemia]. / Pathophysiologie der chronischen Myokardischämie.

Myocardial ischemia is caused by a mismatch between myocardial oxygen supply and myocardial oxygen requirements. Obstructive coronary artery disease (CAD) is the most common cause for myocardial ischemia. Although coronary bypass graft (CABG) surgery und percutaneous coronary interventions (PCI) are established therapies to treat CAD, 10 years after CABG or PCI 40% of the patients still have angina pectoris. Besides obstructive CAD, chronic myocardial ischemia can be induced by small vessel disease and endothelial dysfunction that is not treatable with CABG or PCI. On the cellular basis myocardial ischemia leads to a sodium overload that is caused by an increase in the late sodium current (I Na, late). The increased intracellular sodium concentration leads to a mode switch of the sodium/calcium exchanger (NCX) that now eliminates sodium from the cell and transports calcium into the cell. The resulting calcium overload activates the contractile myofilaments causing an increased wall tension in diastole which compromises the microcirculation and intensifies myocardial ischemia.

Etanercept suppresses regenerative hyperplasia in psoriasis by acutely downregulating epidermal expression of interleukin (IL)-19, IL-20 and IL-24.

BACKGROUND: Psoriasis is a Th17/Th1-mediated skin disease that often responds to antitumour necrosis factor (TNF)-α therapies, such as etanercept. OBJECTIVES: To better define mechanisms by which etanercept improves psoriasis and to gain insight into disease pathogenesis. METHODS: We investigated the early biochemical and cellular effects of etanercept on skin lesions in responder patients prior to substantial clinical improvement (≤ 4 weeks). RESULTS: By 1 week, etanercept acutely suppressed gene expression of the interleukin (IL)-20 subfamily of cytokines (IL-19, IL-20, IL-24), which were found to be predominantly epidermis-derived and which are implicated in stimulating epidermal hyperplasia. Additionally, by 1 week of therapy, suppression of other keratinocyte-derived products (chemokines, antimicrobial proteins) occurred, while suppression of epidermal regenerative hyperplasia occurred within 1-3 weeks. Th17 elements (IL-23p19, IL-12p40, IL-17A, IL-22) were suppressed by 3-4 weeks. In vitro, TNF-α and IL-17A coordinately stimulated the expression of the IL-20 subfamily in normal keratinocytes. CONCLUSIONS: Based on the rapid suppression of regenerative hyperplasia, chemokines and other keratinocyte-derived products, including the IL-20 subfamily, we propose that epidermal activation is a very early target of etanercept. As many of these keratinocyte markers are stimulated by TNF-α, their rapid downregulation is likely to reflect etanercept's antagonism of TNF-α. Additionally, decreased epidermal hyperplasia might result specifically from acute suppression of the IL-20 subfamily, which is also a likely consequence of etanercept's antagonism of TNF-α. Thus, the IL-20 subfamily has potential importance in the pathogenesis of psoriasis and therapeutic response to etanercept.

Chest wall shrapnel-induced beryllium-sensitization and associated pulmonary disease.

Chronic beryllium disease (CBD) is an exposure-related granulomatous disease mimicking sarcoidosis. Beryllium exposure-associated disease occurs mainly via inhalation, but skin may also be a source of sensitization. A 65-year-old male with a history of war-related shrapnel wounds was initially diagnosed with pulmonary sarcoidosis. Twenty years later, the possibility of a metal-related etiology for the lung disease was raised. A beryllium lymphocyte proliferation test, elemental analysis of removed shrapnel, and genetic studies were consistent with a diagnosis of CBD. This case demonstrates that retained beryllium-containing foreign bodies can be linked to a pathophysiologic response in the lung consistent with CBD.

Unique and shared systemic biomarkers for emphysema in Alpha-1 Antitrypsin deficiency and chronic obstructive pulmonary disease.

BACKGROUND: Alpha-1 Antitrypsin (AAT) deficiency (AATD), the most common genetic cause of emphysema presents with unexplained phenotypic heterogeneity in affected subjects. Our objectives to identify unique and shared AATD plasma biomarkers with chronic obstructive pulmonary disease (COPD) may explain AATD phenotypic heterogeneity. METHODS: The plasma or serum of 5,924 subjects from four AATD and COPD cohorts were analyzed on SomaScan V4.0 platform. Using multivariable linear regression, inverse variance random-effects meta-analysis, and Least Absolute Shrinkage and Selection Operator (LASSO) regression we tested the association between 4,720 individual proteins or combined in a protein score with emphysema measured by 15th percentile lung density (PD15) or diffusion capacity (DLCO) in distinct AATD genotypes (Pi*ZZ, Pi*SZ, Pi*MZ) and non-AATD, PiMM COPD subjects. AAT SOMAmer accuracy for identifying AATD was tested using receiver operating characteristic curve analysis. FINDINGS: In PiZZ AATD subjects, 2 unique proteins were associated with PD15 and 98 proteins with DLCO. Of those, 68 were also associated with DLCO in COPD also and enriched for three cellular component pathways: insulin-like growth factor, lipid droplet, and myosin complex. PiMZ AATD subjects shared similar proteins associated with DLCO as COPD subjects. Our emphysema protein score included 262 SOMAmers and predicted emphysema in AATD and COPD subjects. SOMAmer AAT level <7.99 relative fluorescence unit (RFU) had 100% sensitivity and specificity for identifying Pi*ZZ, but it was lower for other AATD genotypes. INTERPRETATION: Using SomaScan, we identified unique and shared plasma biomarkers between AATD and COPD subjects and generated a protein score that strongly associates with emphysema in COPD and AATD. Furthermore, we discovered unique biomarkers associated with DLCO and emphysema in PiZZ AATD. FUNDING: This work was supported by a grant from the Alpha-1 Foundation to RPB. COPDGene was supported by Award U01 HL089897 and U01 HL089856 from the National Heart, Lung, and Blood Institute. Proteomics for COPDGene was supported by NIH 1R01HL137995. GRADS was supported by Award U01HL112707, U01 HL112695 from the National Heart, Lung, and Blood Institute, and UL1TRR002535 to CCTSI; QUANTUM-1 was supported by the National Heart Lung and Blood Institute, the Office of Rare Diseases through the Rare Lung Disease Clinical Research Network (1 U54 RR019498-01, Trapnell PI), and the Alpha-1 Foundation. COPDGene is also supported by the COPD Foundation through contributions made to an Industry Advisory Board that has included AstraZeneca, Bayer Pharmaceuticals, Boehringer-Ingelheim, Genentech, GlaxoSmithKline, Novartis, Pfizer, and Sunovion.

SELDI-TOF derived serum biomarkers failed to differentiate between patients with beryllium sensitisation and patients with chronic beryllium disease.

BACKGROUND: People exposed to beryllium may develop beryllium sensitisation (BeS) and, in some cases, progress to chronic beryllium disease (CBD). OBJECTIVES: The objective of this study was to test the ability of proteomic technology to identify patterns of serum protein biomarkers that allow differentiation between BeS and CBD and thus remove the need for invasive bronchoscopic procedures. METHODS: Initially, SELDI-TOF methodology and analysis was performed on serum samples from 30 CBD and 31 BeS patients. RESULTS: This 'starter set' yielded two distinct biomarker pattern sets with eight candidate proteins. The first set differentiated between BeS and CBD with 83.3% sensitivity and 82.3% specificity, with 10-fold cross-validation of 75% and 79%, respectively. The second set of biomarkers yielded higher sensitivity (90.0%) and higher specificity (90.3%), with 10-fold cross-validation of 71.7% and 82.3%, respectively. Due to its greater sensitivity and specificity, the second set of biomarkers was used as the framework for differentiating between CBD and BeS in a second set of serum samples from 450 patients with BeS and CBD. When this larger set of samples was subjected to the biomarker framework in a blinded fashion, it yielded a sensitivity of 43.53% and a specificity of 38.93%. CONCLUSIONS: Due to these low sensitivity and specificity values, we have concluded that, currently, the unique set of SELDI-TOF derived biomarkers does not possess the qualities that would allow it to differentiate between a CBD patient and a BeS patient using serum protein biomarkers. Future refinements in sample collection or proteomic technology may be needed to improve biomarker discovery.