Spectroscopic and computational studies of a bifunctional iron- and 2-oxoglutarate dependent enzyme, AsqJ.

Iron and 2-oxoglutarate dependent (Fe/2OG) enzymes exhibit an exceedingly broad reaction repertoire. The most prevalent reactivity is hydroxylation, but many other reactivities have also been discovered in recent years, including halogenation, desaturation, epoxidation, endoperoxidation, epimerization, and cyclization. To fully explore the reaction mechanisms that support such a diverse reactivities in Fe/2OG enzyme, it is necessary to utilize a multi-faceted research methodology, consisting of molecular probe design and synthesis, in vitro enzyme assay development, enzyme kinetics, spectroscopy, protein crystallography, and theoretical calculations. By using such a multi-faceted research approach, we have explored reaction mechanisms of desaturation and epoxidation catalyzed by a bi-functional Fe/2OG enzyme, AsqJ. Herein, we describe the experimental protocols and computational workflows used in our studies.

The effect of long-term tafamidis treatment on quality of life in people with transthyretin amyloid cardiomyopathy (ATTR-CM): A plain language summary.

WHAT IS THIS SUMMARY ABOUT?: This summary explains some results of a study called ATTR-ACT and its ongoing long-term extension study that were published in the European Journal of Heart Failure. The purpose of ATTR-ACT was to find out if a drug called tafamidis is an effective treatment for people with a heart condition called transthyretin amyloid cardiomyopathy (ATTR-CM). People took tafamidis or placebo for up to 2.5 years in ATTR-ACT (the initial study). A placebo looks like the study medicine but does not contain any active ingredients. After people completed the initial study, they could take part in the extension study. An extension study allows people to continue receiving treatment after the original clinical study ends and helps researchers understand how well a treatment works over a longer time period. This extension study allows people to receive tafamidis for up to an additional 5 years. People who took placebo in the initial study now receive tafamidis. People who took tafamidis in the initial study continue tafamidis treatment. Researchers looked at changes in peoples' ability to enjoy life ('quality of life') and heart failure symptoms since they started ATTR-ACT. Results are available for the first 2.5 years of the extension study. WHAT ARE THE KEY TAKEAWAYS?: During the initial study, there was less worsening of quality of life and heart failure symptoms in people who took tafamidis compared to people who took placebo. In the extension study, quality of life and heart failure symptoms were maintained or nearly maintained in people who took tafamidis in the initial study. In people who started tafamidis in the extension study, quality of life and heart failure symptoms continued to worsen, but the worsening slowed down. WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?: Tafamidis slows the worsening of quality of life and heart failure symptoms in people with ATTR-CM. People with ATTR-CM should start treatment early to receive the most benefit.Clinical Trial Registration: NCT01994889 (ATTR-ACT) (ClinicalTrials.gov).

Molecular Basis of the Substrate Specificity of Phosphotriesterase from Pseudomonas diminuta: A Combined QM/MM MD and Electron Density Study.

The occurrence of organophosphorus compounds, pesticides, and flame-retardants in wastes is an emerging ecological problem. Bacterial phosphotriesterases are capable of hydrolyzing some of them. We utilize modern molecular modeling tools to study the hydrolysis mechanism of organophosphorus compounds with good and poor leaving groups by phosphotriesterase from Pseudomonas diminuta (Pd-PTE). We compute Gibbs energy profiles for enzymes with different cations in the active site: native Zn2+cations and Co2+cations, which increase the steady-state rate constant. Hydrolysis occurs in two elementary steps via an associative mechanism and formation of the pentacoordinated intermediate. The first step, a nucleophilic attack, occurs with a low energy barrier independently of the substrate. The second step has a low energy barrier and considerable stabilization of products for substrates with good leaving groups. For substrates with poor leaving groups, the reaction products are destabilized relative to the ES complex that suppresses the reaction. The reaction proceeds with low energy barriers for substrates with good leaving groups with both Zn2+and Co2+cations in the active site; thus, the product release is likely to be a limiting step. Electron density and geometry analysis of the QM/MM MD trajectories of the intermediate states with all considered compounds allow us to discriminate substrates by their ability to be hydrolyzed by the Pd-PTE. For hydrolyzable substrates, the cleaving bond between a phosphorus atom and a leaving group is elongated, and electron density depletion is observed on the Laplacian of electron density maps.

ADHD caregivers facing the COVID-19: the lockdown's impact on emotion and parenting strategies.

BACKGROUND: Recent literature highlighted the relevance of parenting strategies and emotions in dealing with children with ADHD and showed that these dimensions were highly affected by the COVID-19 lockdowns. Thus, our research investigated the impact that the COVID-19 pandemic had on caregivers of children with attention deficit hyperactivity disorder (ADHD). We focused on the role of medications, children's age, and distance learning on changes in caregivers' emotions and parenting strategies. METHODS: Nine hundred ninety-two caregivers completed an anonymous online questionnaire. The survey enquired caregivers about children's pharmacological therapy, difficulties in distance learning, and caregivers' parenting strategies and emotions before and during the lockdown. RESULTS: Our results showed that caregivers experienced relevant difficulties in distance learning and that they felt more frustration emotions and employed more negative parenting strategies than before the pandemic. While pharmacological therapy was not a significant predictor of changes in neither positive nor negative parenting strategies, children's age and learning burden proved to predict caregivers' changes in positive parenting strategies. Moreover, our mediation analysis showed that the learning burden (e.g., homework increasing and children's reliance on caregivers) partially mediates the effect of age on changes in positive strategies. The older the children, the less the burden, and the less the change in positive strategies. CONCLUSIONS: These results describe lockdown's impact on caregivers' experience in dealing with children with ADHD and explain how they adapted to it by changing their parenting strategies.

Evaluating the Efficacy of Infliximab in Inflammatory Bowel Disease: A Systematic Review of the Literature.

The introduction of steroid therapy in 1955 markedly decreased the mortality rate of severe ulcerative colitis (UC) from 24% in the placebo group to 7%, and it is currently less than 1% in specialist centers. Despite this advancement, the response of severe UC to steroids has stagnated over the past 50 years, with a high rate of colectomy persisting for severe to moderately severe cases. Infliximab (IFX) (Remicade, Centocor Inc., Malvern, PA, United States), an intravenously administered chimeric monoclonal immunoglobulin G1 antibody targeting tumor necrosis factor-alpha (TNF-α), has shown efficacy in numerous randomized controlled trials for treating moderate to severe and fistulizing Crohn's disease, particularly in patients unresponsive to conventional therapies. This led to its approval by the US Food and Drug Administration in 1998 for treating active and fistulizing Crohn's disease. Most clinical research on IFX has focused on Crohn's disease, which is characterized as a Th1-type condition driven by pro-inflammatory cytokines like TNF-α. Conversely, UC has traditionally been viewed as a Th2-type condition where TNF-α plays a lesser role. However, recent studies indicate that TNF-α might also contribute to the pathogenesis of UC. These findings highlight the necessity for larger randomized controlled trials to further investigate the benefits of therapies like IFX, with the ultimate goal of improving treatment outcomes and quality of life for patients with inflammatory bowel disease.

Navigating Prevention: A Systematic Review of Strategies for Alzheimer's Disease in High-Risk and Affected Individuals.

Alzheimer's disease (AD) remains a widespread cause of dementia globally, and its prevalence is increasing due to the aging population. Two key pathologies typically identify this neurodegenerative disease process: the accumulation of amyloid plaques and the formation of neurofibrillary tangles containing hyperphosphorylated tau. Diagnosis relies on the patient's clinical presentation meeting specific criteria, along with the use of fluid and imaging biomarkers. The current treatment focuses on addressing symptoms, with ongoing trials aiming to decrease the production and overall impact of brain pathology. Here, we explore various methods to minimize the risks of AD in patients and individuals at high risk of developing it. To address this, we carefully selected 10 articles that discuss various prevention methods used today to promote brain health, including diets that are believed to have neuroprotective properties. The study findings emphasize the importance of further strengthening the evidence and conducting larger randomized controlled trials to gain a better understanding of the potential benefits for individuals at high risk of developing AD, as well as those already diagnosed with it.

Sequencing and characterization of complete mitogenome DNA of worldwide turkey (Meleagris gallopavo) populations.

The history of turkey (Meleagris gallopavo) domestication can be traced back to the period between 700 and 200 BC in Mexico. This process involved multiple contributors and resulted in the development of modern local turkey breeds. This research investigates the complete mitochondrial diversity across a diverse range of local turkeys. Seventy-three turkeys were sampled from various populations, including autochthonous Italian breeds, an American breed (Narragansett), as well as wild turkeys from the USA and Mexico. The mitochondrial DNA (mtDNA) was employed as a powerful tool for biodiversity and breed phylogeny investigation. An analysis of the entire mtDNA was conducted to identify breed-specific unique traits, mitochondrial-specific characteristics, and the phylogenetic relationship among turkey populations. A total of 44 polymorphic sites were identified. Brianzolo and Narragansett birds were characterized as genetically homogeneous populations. Thirty-two different haplotypes were identified when our samples were compared with mtDNA D-loop of 96 online available turkeys from various geographical countries. H1 and H2, differing for one mutation, were the most abundant, comprising 132 of the 185 sequences. H1 included samples coming from every region, while H2 was predominantly characterized by Italian samples. USA and Mexican samples appear to be more variable in their mtDNA than the other populations.

Spatial Transcriptomic Approach to Understanding Coronary Atherosclerotic Plaque Stability.

BACKGROUND: Coronary atherosclerotic plaques susceptible to acute coronary syndrome have traditionally been characterized by their surrounding cellular architecture. However, with the advent of intravascular imaging, novel mechanisms of coronary thrombosis have emerged, challenging our contemporary understanding of acute coronary syndrome. These intriguing findings underscore the necessity for a precise molecular definition of plaque stability. Considering this, our study aimed to investigate the vascular microenvironment in patients with stable and unstable plaques using spatial transcriptomics. METHODS: Autopsy-derived coronary arteries were preserved and categorized by plaque stability (n=5 patients per group). We utilized the GeoMx spatial profiling platform and Whole Transcriptome Atlas to link crucial histological morphology markers in coronary lesions with differential gene expression in specific regions of interest, thereby mapping the vascular transcriptome. This innovative approach allowed us to conduct cell morphological and spatially resolved transcriptional profiling of atherosclerotic plaques while preserving crucial intercellular signaling. RESULTS: We observed intriguing spatial and cell-specific transcriptional patterns in stable and unstable atherosclerotic plaques, showcasing regional variations within the intima and media. These regions exhibited differential expression of proinflammatory molecules (eg, IFN-γ [interferon-γ], MHC class II, proinflammatory cytokines) and prothrombotic signaling pathways. By using lineage tracing through spatial deconvolution of intimal CD68+ (cluster of differentiation 68) cells, we characterized unique, intraplaque subpopulations originating from endothelial, smooth muscle, and myeloid lineages with distinct regional locations associated with plaque instability. In addition, unique transcriptional signatures were observed in vascular smooth muscle and CD68+ cells among plaques exhibiting coronary calcification. CONCLUSIONS: Our study illuminates distinct cell-specific and regional transcriptional alterations present in unstable plaques. Furthermore, we characterize the first spatially resolved, in situ evidence supporting cellular transdifferentiation and intraplaque plasticity as significant contributors to plaque instability in human coronary atherosclerosis. Our results provide a powerful resource for the identification of novel mediators of acute coronary syndrome, opening new avenues for preventative and therapeutic treatments.

Urinary extracellular vesicles as a monitoring tool for renal damage in patients not meeting criteria for chronic kidney disease.

Background: Current definition of chronic kidney disease (CKD) identifies only advanced stages, but effective management demands early detection. Urinary albumin-to-creatinine ratio (ACR) 30 mg/g is a cut-off point for CKD clinical diagnosis. Patients with lower values (normoalbuminuria) and eGFR > 60 mL/min/1.73 m2 are considered at no increased cardiorenal risk. However, higher incidence of renal function decline and cardiovascular events have been shown within the normoalbuminuria range. Novel subclinical indicators may help to identify higher-risk patients. Urinary extracellular vesicles (uEVs) are sentinels of renal function non-invasively. Here we aimed to approach the early assessment of cardiorenal risk by investigating the protein cargo of uEVs. Methods: Hypertensive patients were classified in control group (C) with ACR < 10 mg/g, and high-normal group (HN) with ACR 10-30 mg/g. Isolated uEVs were characterized by western blotting and electron microscopy and the protein cargo was analyzed by untargeted proteomics (LC-MS/MS) in a first discovery cohort. Protein confirmation was performed in a different cohort by ExoView. Immunohistochemistry of human kidney biopsies was also performed to evaluate the potential of uEVs to reflect renal damage. Results: HN albuminuria does not affect the uEVs concentration, size, or tetraspanin profile. Among >6200 uEVs proteins identified, 43 define a panel significantly altered in HN patients without variation in urine, mostly annotated in the tubule (39 out of 43). The tubular transporter long-chain fatty acid transport protein 2 (SLC27A2) and the apical membrane protein amnionless (AMN) confirmed their alteration in HN patients evidencing impaired tubular reabsorption. SLC27A2 showed tubular expression and significantly reduced levels in patients with diagnostic criteria for CKD. Conclusions: Alterations in the EV-mediated molecular profile are evident before pathological ACR levels are reached. Direct quantitation of SLC27A2 and AMN in uEVs helps identifying normoalbuminuric subjects with higher cardiorenal risk in early monitoring of CKD.

Correlated evolution of dispersal traits and habitat preference in the melicgrasses.

PREMISE: Seed dispersal is a critical process impacting individual plants and their communities. Plants have evolved numerous strategies and structures to disperse their seeds, but the evolutionary drivers of this diversity remain poorly understood in most lineages. We tested the hypothesis that the evolution of wind dispersal traits within the melicgrasses (Poaceae: Meliceae Link ex Endl.) was correlated with occupation of open and disturbed habitats. METHODS: To evaluate wind dispersal potential, we collected seed dispersal structures (diaspores) from 24 melicgrass species and measured falling velocity and estimated dispersal distances. Species' affinity for open and disturbed habitats were recorded using georeferenced occurrence records and land cover maps. To test whether habitat preference and dispersal traits were correlated, we used phylogenetically informed multilevel models. RESULTS: Melicgrasses display several distinct morphologies associated with wind dispersal, suggesting likely convergence. Open habitat taxa had slower-falling diaspores, consistent with increased wind dispersal potential. However, their shorter stature meant that dispersal distances, at a given wind speed, were not higher than those of their forest-occupying relatives. Species with affinities for disturbed sites had slower-falling diaspores and greater wind dispersal distances, largely explained by lighter diaspores. CONCLUSIONS: Our results are consistent with the hypothesized evolutionary relationship between habitat preference and dispersal strategy. However, phylogenetic inertia and other plant functions (e.g., water conservation) likely shaped dispersal trait evolution in melicgrasses. It remains unclear if dispersal trait changes were precipitated by or predated changing habitat preferences. Nevertheless, our study provides promising results and a framework for disentangling dispersal strategy evolution.

Attainment of EULAR/ERA-EDTA targets of therapy with current immunosuppressive regimens and adjustments in treatment: a multicentre, real-life observational study.

OBJECTIVE: To estimate real-life European Alliance of Associations for Rheumatology (EULAR)/European Renal Association (ERA)-European Dialysis and Transplantation Association (EDTA) response rates and predictors for no response in patients with lupus nephritis (LN) managed with conventional immunosuppressive therapies. METHODS: Ambidirectional cohort study of patients with new-onset LN (period 2014-to date). Response rates in the first year were calculated, and all treatment modifications were recorded. Univariate and multivariate regression analyses were performed to assess determinants of failure to respond at 12 months. RESULTS: 140 patients were included (81.4% women, median (IQR) age at LN diagnosis 38 (22) years). Among them, 32.1% presented with nephrotic range proteinuria, 28.6% with glomerular filtration rate <60 mL/min, 76.6% had proliferative and 19.7% class V LN. Initial treatment consisted of cyclophosphamide in 51.4% of patients (84.7% high-dose, 15.3% low-dose) and mycophenolate in 32.1%. 120 patients had available data at 12 months. EULAR/ERA-EDTA renal response rates at 3, 6 and 12 months were achieved by 72.6%, 78.5% % and 69.2% of patients, respectively. In multivariate analysis, increased Chronicity Index at baseline was associated with failure to achieve either complete or partial response at 12 months (OR 2.26, 95% CI 1.35 to 3.77). Notably, 20% of patients required treatment modifications due to suboptimal response during the first 12 months, with the addition of or switch to a different immunosuppressive drug in seven and nine patients, respectively. CONCLUSIONS: More than two-thirds of patients with LN attain EULAR/ERA-EDTA response rates by 12 months, but 20% require therapy modifications within this time period. Patients with increased chronicity in baseline biopsy, when combined with histological activity, are at higher risk for a lack of clinical response.

Immune correlates analysis of the Imbokodo (HVTN 705/HPX2008) efficacy trial of a mosaic HIV-1 vaccine regimen evaluated in Southern African people assigned female sex at birth: a two-phase case-control study.

BACKGROUND: The HVTN 705 Imbokodo trial of 2636 people without HIV and assigned female sex at birth, conducted in southern Africa, evaluated a heterologous HIV-1 vaccine regimen: mosaic adenovirus 26-based vaccine (Ad26.Mos4.HIV) at Months 0, 3, 6, 12 and alum-adjuvanted clade C gp140 at Months 6, 12. Per-protocol vaccine efficacy (VE) against HIV-1 diagnosis from seven to 24 months was 14.1% (95% CI: -22.0% to 39.5%). Immune correlates analysis was performed for markers selected based on prior evidence in efficacy trials and/or nonhuman primate models. METHODS: Humoral and cellular immune response markers at Month 7 were evaluated as immune correlates of risk and of protection in a breakthrough case-control cohort (n = 52 cases, 246 non-cases). Primary markers were IgG binding to vaccine-strain gp140, IgG3 binding to diverse Env antigens (IgG3 Env breadth), IgG3 binding to diverse V1V2 antigens (IgG3 V1V2 breadth), antibody-dependent phagocytosis against the vaccine-strain gp140, Env-specific CD4+ and CD8+ T-cell responses, and multi-epitope functions. FINDINGS: No immune markers were statistically significant correlates of risk. IgG3 V1V2 breadth trended toward an inverse association: hazard ratio 0.70 (95% CI: 0.36 to 1.35; p = 0.29) per 10-fold increase and 0.51 (95% CI: 0.21 to 1.24; p = 0.14) in a Cox model with all primary markers. The VE estimate was 11.8% (95% CI: -17.9% to 34.0%) at all IgG3 V1V2 breadth values below 667 weighted geometric mean net MFI; just above this value, the VE estimate sharply increased to 62.6% (95% CI: -17.9% to 89.6%), and further increased to 80.9% (95% CI: -17.9% to 99.5%) at 1471 MFI, the 95th percentile of the marker distribution. Mediation analysis yielded a VE of 35.7% (95% CI: 15.0% to 51.3%) attributable to the vaccine's impact on this marker. INTERPRETATION: The trend in association of greater IgG3 V1V2 antibody breadth with lower likelihood of HIV acquisition is consistent with the identification of antibodies against V1V2 as immune correlates in three other HIV vaccine efficacy trials and suggests that a greater emphasis should be placed on studying this region in the HIV-1 envelope as a vaccine immunogen. FUNDING: National Institute of Allergy and Infectious Diseases and Janssen Vaccines & Prevention BV.

Pathways to strengthen the climate resilience of health systems in the Peruvian Amazon by working with Indigenous leaders, communities and health officers.

BACKGROUND: Indigenous knowledge and responses were implemented during the COVID-19 pandemic to protect health, showcasing how Indigenous communities participation in health systems could be a pathway to increase resilience to emergent hazards like climate change. This study aimed to inform efforts to enhance climate change resilience in a health context by: (1) examining if and how adaptation to climate change is taking place within health systems in the Peruvian Amazon, (2) understanding how Indigenous communities and leaders' responses to climatic hazards are being articulated within the official health system and (3) to provide recommendations to increase the climate change resilience of Amazon health systems. METHODS: This study was conducted among two Peruvian Amazon healthcare networks in Junin and Loreto regions. A mixed methodology design was performed using a cross-sectional survey (13 healthcare facilities), semistructured interviews (27 official health system participants and 17 Indigenous participants) and two in-person workshops to validate and select key priorities (32 participants). We used a climate-resilient health system framework linked to the WHO health systems building blocks. RESULTS: Indigenous and official health systems in the Peruvian Amazon are adapting to climate change. Indigenous responses included the use of Indigenous knowledge on weather variability, vegetal medicine to manage health risks and networks to share food and resources. Official health responses included strategies for climate change and response platforms that acted mainly after the occurrence of climate hazards. Key pathways to articulate Indigenous and official health systems encompass incorporating Indigenous representations in climate and health governance, training the health work force, improving service delivery and access, strengthening the evidence to support Indigenous responses and increasing the budget for climate emergency responses. CONCLUSIONS: Key resilience pathways call for a broader paradigm shift in health systems that recognises Indigenous resilience as valuable for health adaptation, moves towards a more participatory health system and broadens the vision of health as a dimension inherently tied to the environment.

Cardiovascular and Renal Treatment in Heart Failure Patients with Hyperkalemia or High Risk of Hyperkalemia: Rationale and Design of the CARE-HK in HF Registry.

BACKGROUND: Despite guideline recommendations, many patients with heart failure (HF) do not receive target doses of renin-angiotensin-aldosterone system inhibitors (RAASis) in clinical practice due, in part, to concerns about hyperkalemia (HK). METHODS AND RESULTS: This non-interventional, multinational, multicenter registry (NCT04864795; 111 sites in Europe and the USA) enrolled 2,558 eligible adults with chronic HF (mostly with reduced ejection fraction [HFrEF]). Eligibility criteria included use of angiotensin-converting-enzyme inhibitor / angiotensin-II receptor blocker / angiotensin-receptor-neprilysin inhibitor, candidate for or treatment with mineralocorticoid receptor antagonist, and increased risk of HK (eg, current serum potassium >5.0 mmol/L], history of HK in the previous 24 months, or estimated glomerular filtration rate <45 mL/min/1.73 m2). Information on RAASi and other guideline-recommended therapies was collected retrospectively and prospectively (≥6 months). Patients were followed according to local clinical practice, without study-specific visits or interventions. The main objectives were to characterize RAASi treatment patterns compared with guideline recommendations, describe RAASi modifications following episodes of HK, and describe RAASi treatment in patients treated with patiromer. Baseline characteristics for the first 1,000 patients are presented. CONCLUSIONS: CARE-HK is a multinational prospective HF registry designed to report on the management and outcomes of patients with HF at high risk for HK in routine clinical practice.

Rapid Efficacy of riSankizumab in pretibial psoriasis invOLVEment: RESOLVE.

Background: Despite extraordinary improvements in the management of psoriasis in recent times, some areas of the body, such as the pretibial area, still show an unsatisfactory response and a more significant impact on patient quality of life. This multicentre study focuses on psoriasis affecting sensitive areas (particularly the pretibial area), its impact on quality of life and the therapeutic response to risankizumab. Methods: This multicentre prospective observational study recruited patients with moderate-to-severe psoriasis with pretibial area involvement. All patients underwent treatment with risankizumab (150 mg every 3 weeks), and efficacy was assessed after 24 weeks. Results: The study included 128 patients with a mean age of 51 years, suffering from moderate-to-severe psoriasis with involvement of the pretibial area with median total Psoriasis Area Severity Index score of 17.05 and Dermatology Life Quality Index of 16.27. The group was further divided into two sub-groups: the 'mother patch' group, in whom the very first psoriatic plaque appeared in the pretibial region (45 patients), and the 'non-mother patch' group, in whom the psoriatic lesion in the pretibial region was present but not as the first manifestation (83 patients). In order to better assess the involvement of psoriasis in the pretibial area, the pretibial plaque lesion severity index was also calculated at baseline in all patients: extent 2.75, erythema 2.64, infiltration 2.45 and desquamation 2.38. All participants in this study showed a good therapeutic response, with a reduction in all scores. Conclusions: The pretibial area is becoming an object of therapeutic interest due to some resistance to clearance and the consequent impairment of patient quality of life. This study showed that risankizumab can give favourable therapeutic results not only in patients with moderate-to-severe psoriasis with involvement of the difficult-to-treat areas but particularly in patients with recalcitrant plaques in the pretibial area.

Oropouche Fever, Cuba, May 2024.

Phylogenetic analyses showed that the virus responsible for a May 2024 Oropouche fever outbreak in Cuba was closely related to viruses from Brazil in 2023. Pools of Ceratopogonidae spp. biting midges and Culex quinquefasciatus mosquitoes were positive for Oropouche viral RNA. No cases were severe. Virus extension to new areas may increase case numbers and severity.

Analysis of the Structure of 14 Therapeutic Antibodies Using Circular Dichroism Spectroscopy.

Understanding the impact of the manufacturing environment on therapeutic monoclonal antibody (mAb) structures requires new process analytical technology. Here, we describe the creation of a new reference set for the circular dichroism (CD) spectra of mAbs. Data sets of the highest quality were collected by synchrotron radiation CD for 14 different mAbs in both native and acid-stressed states. Deconvolution of far-UV spectra for the mAb cohort identified two current reference sets (SP175 and SMP180) as assigning accurate secondary structures, irrespective of the analysis program employed. Scrutiny of spectra revealed significant variation in the far-UV and especially near-UV CD of the 14 mAbs. Two spectral features were found to be sensitive to changes in solution pH, i.e., the far-UV positive peak at 201-202 nm and the near-UV negative exciton couplet around 230-240 nm. The latter feature offers attractive possibilities for in-line CD-based monitoring of the mAb structure during manufacture.

Whole-exome sequencing uncovers the genetic complexity of bicuspid aortic valve in families with early-onset complications.

Bicuspid aortic valve (BAV) is the most common congenital heart lesion with an estimated population prevalence of 1%. We hypothesize that specific gene variants predispose to early-onset complications of BAV (EBAV). We analyzed whole-exome sequences (WESs) to identify rare coding variants that contribute to BAV disease in 215 EBAV-affected families. Predicted damaging variants in candidate genes with moderate or strong supportive evidence to cause developmental cardiac phenotypes were present in 107 EBAV-affected families (50% of total), including genes that cause BAV (9%) or heritable thoracic aortic disease (HTAD, 19%). After appropriate filtration, we also identified 129 variants in 54 candidate genes that are associated with autosomal-dominant congenital heart phenotypes, including recurrent deleterious variation of FBN2, MYH6, channelopathy genes, and type 1 and 5 collagen genes. These findings confirm our hypothesis that unique rare genetic variants drive early-onset presentations of BAV disease.