Light Chain Research Articles

The identification and correction of pseudohypercalcemia.

We found that a subset of patients with monoclonal gammopathy exhibited hypercalcemia without apparent causes or clinical manifestations In a cohort of 289 monoclonal gammopathy patients, 2.4% presented with such atypical hypercalcemia, with one notable case exhibiting normal ionized calcium levels, suggesting the presence of pseudohypercalcemia. The aim of this study is to elucidate the factors contributing to pseudohypercalcemia in monoclonal gammopathy and to develop a novel globulin-corrected calcium formula for clinical application. This observational study enrolled 110 monoclonal gammopathy patients from our center. An additional 33 patients were recruited to validate the newly proposed formula. Univariate analysis identified potential risk factors. And multivariate logistic regression identified definitive influential factors. The determined influential factors were utilized to develop a formula by multiple linear regression, which was validated by a paired t-test and the Youden index. This study found that globulin was a risk factor for pseudohypercalcemia. It revealed that pseudohypercalcemia should be considered in patients with globulin levels ≥61 g/L (P=0.014). Both albumin and globulin were confirmed as independent factors associated with bound calcium. Given that, we developed a formula to correct ionized calcium levels, which was consistent with ionized calcium tested by blood gas analysis. The diagnostic accuracy of the new formula (Youden index is 0.906) is better than the traditional formula (Youden index is 0.906). Interestingly, all monoclonal immunoglobulin types, except for light chains, showed an equal propensity to develop pseudohypercalcemia (P=0.306). It also showed a linear correlation between IgA, IgG, and IgM and bound calcium. This study confirmed that elevated globulin affects serum total calcium and offered the threshold of globulin ≥ 61 g/L in the differential diagnosis of peudohypercalcemia from hypercalcemia. The new formula based on albumin and globulin was developed, which was verified to be better than the traditional formula for correctly diagnosing hypercalcemia. In addition, we found that neither light chains nor heavy chains of monoclonal immunoglobulin alone can result in pseudohypercalcemia.

Antibody titer after anti-idiotype rabies vaccination with nano-chitosan adjuvant

Background.The rabies virus neutralizing antibodies titers is a public health problem in the world, including Indonesia. Rabies is zoonotic and causes death in humans with a case fatality rate of 100%. Anti-idiotype antibody (Ab2) from chicken immunoglobulin (IgY) can be a substitute antigen for the rabies virus. This research aims to study the potential of rabies vaccine based on anti-idiotype antibody (Ab2) with nano-chitosan as an adjuvant.Materials and methods.The production of Ab2 is derived from purified and characterized chicken immunoglobulins. Nano-chitosan is made from chitosan from shrimp shell waste. Vaccination tests were carried out on rats compared with commercial vaccines as a positive control and physiological solutions as a negative control. The characterization results of IgY Ab2 were IgY rabies with BM ~180 kDa, heavy chains (BM ~60 kDa), and light chains (BM ~30 kDa) of IgY. Nano-chitosan is less than 100 nm in size, can dissolve well, and does not cause side effects in experimental animals.Results.The vaccine formula uses a concentration of 0.5%, where the ratio of nano-chitosan and Ab2 is 1:1. The Ab2 concentration used was about 1000 units per mL of the Ab2 suspension.Conclusion.This study concludes that anti-idiotype antibodies dissolved in nano-chitosan adjuvant can induce the formation of antibodies with titers that are not statistically different from the antibody titers induced by commercial rabies vaccines. Nano-chitosan has a potential vaccine adjuvant candidate, safe to use, and can enhance the immunogenicity of an antigen applied subcutaneously. According to the results of this study, it is recommended that post-vaccination antibody titers be measured regularly: for example, every one week for six weeks after vaccination. This measurement determines the time of the peak of the antibody titer so that the time for revaccination can be determined.

End-To-End Automated Intact Protein Mass Spectrometry for High-Throughput Screening and Characterization of Bispecific and Multispecific Antibodies.

Bispecific antibodies (bsAbs) and multispecific antibodies (msAbs) represent a promising frontier in therapeutic antibody development, offering unique capabilities not achievable with traditional monoclonal antibodies. Despite their potential, significant challenges remain due to their increased molecular complexity. One prominent challenge is the correct assembly of light and heavy chains, as improper pairing leads to mispaired or incompletely assembled species that lack therapeutic efficacy and possess undesired properties, impairing the developability, manufacturability, and safety. There is a critical need for rapid, sensitive analytical tools to monitor and control these undesired species and ensure the quality assessment of bsAbs and msAbs. To address this need, we present a novel high-throughput, format-agnostic intact mass workflow that significantly enhances the efficiency of detecting and quantifying biotherapeutic products and related impurities. This workflow integrates automated sample preparation, novel high-resolution rapid mass detection powered by SampleStream-MS, and an advanced data analysis pipeline. It offers increased throughput and data quality while substantially reducing analysis turnover time and labor. This was demonstrated in a pilot program where ∼800 multispecific antibodies were processed in 10 working days. The article details the evaluation and validation of our method, demonstrating its repeatability and intermediate precision in terms of measurement accuracy and relative quantification of various product-related species. We underscore the transformative potential of this end-to-end high-throughput workflow in expediting bispecific and multispecific antibody discovery, optimizing production processes, and ensuring high-quality development and manufacturing for therapeutic antibodies.

Free Immunoglobulin Light Chains in Patients With Myocarditis: a New Biomarker of Inflammation and Heart Failure

To study the concentration of immunoglobulin free light chains (FLCs) in patients with myocarditis in comparison with non-inflammatory heart diseases, their relationship with inflammatory markers and the severity of chronic heart failure (CHF). This study included 77 patients (31 women, mean age 54.1±13.3 years): 41 patients with myocarditis verified by myocardial biopsy (n=18) or using a noninvasive diagnostic algorithm, 31 patients with noninflammatory CHF (comparison group), and 5 patients with monoclonal gammopathy identified during the study (4 of them were diagnosed with AL amyloidosis with heart damage). In the myocarditis group, CHF was diagnosed in 29 patients, mean stage IIA, functional class (FC) 2-3, with a mean left ventricular ejection fraction 43%. In the comparison group, patients had predominantly IIA stage, FC 2-3 CHF without systolic dysfunction. The blood concentration of kappa and lambda FLC types was measured with Cloneus S-FLC-K TIA Kit and Cloneus S-FLC-L TIA Kit. Concentrations were considered normal at FLC-kappa 4.84-14.20 mg/l, FLC-lambda 7.03-22.50 mg/l, and the FLC-kappa/lambda ratio 0.426-1.050. Increased FLC concentrations were found in 58% of patients with myocarditis and in 77% of patients in the comparison group. The FLC-lambda concentration was significantly higher in the comparison group; there were no significant differences between the groups in FLC-kappa and their ratio. The closest significant correlations in both groups and the entire cohort were noted between FLCs of either type and CHF, as well as the requirement for loop diuretics (correlation coefficients, 0.60-0.90), independent on the severity of systolic dysfunction. Myocarditis patients also showed correlations of FLCs with the titer of antibodies to cardiomyocyte nuclear antigens, levels of C-reactive protein, leukocytes, neutrophils, erythrocyte sedimentation rate, and the concentration of N-terminal fragment of brain natriuretic peptide. In a subgroup of 10 myocarditis patients who were treated with immunosuppressants, FLCs of both types were significantly lower than in the comparison group; only with the persistence of severe CHF was an increase in FLCs noted. An increased FLC concentration can be considered as an important pathogenesis component that reflects both the specific mechanisms of myocarditis and the severity of CHF. In the absence of a statistically significant increase in general inflammatory markers in the blood of myocarditis patients, the measurement of FLCs can be used as an additional diagnostic marker and predictor of the decompensated variant of the course of myocarditis. However, the diagnostic and prognostic significance of FLC concentration in patients without CHF requires a further study.

Safety and tolerability of tegoprubart in patients with amyotrophic lateral sclerosis: A Phase 2A clinical trial.

The interaction of CD40L and its receptor CD40 on activated T cells and B cells respectively control pro-inflammatory activation in the pathophysiology of autoimmunity and transplant rejection. Previous studies have implicated signaling pathways involving CD40L (interchangeably referred to as CD154), as well as adaptive and innate immune cell activation, in the induction of neuroinflammation in neurodegenerative diseases. This study aimed to assess the safety, tolerability, and impact on pro-inflammatory biomarker profiles of an anti CD40L antibody, tegoprubart, in individuals with amyotrophic lateral sclerosis (ALS). In this multicenter dose-escalating open-label Phase 2A study, 54 participants with a diagnosis of ALS received 6 infusions of tegoprubart administered intravenously every 2 weeks. The study was comprised of 4 dose cohorts: 1 mg/kg, 2 mg/kg, 4 mg/kg, and 8 mg/kg. The primary endpoint of the study was safety and tolerability. Exploratory endpoints assessed the pharmacokinetics of tegoprubart as well as anti-drug antibody (ADA) responses, changes in disease progression utilizing the Revised ALS Functional Rating Scale (ALSFRS-R), CD154 target engagement, changes in pro-inflammatory biomarkers, and neurofilament light chain (NFL). Seventy subjects were screened, and 54 subjects were enrolled in the study. Forty-nine of 54 subjects completed the study (90.7%) receiving all 6 infusions of tegoprubart and completing their final follow-up visit. The most common treatment emergent adverse events (TEAEs) overall (>10%) were fatigue (25.9%), falls (22.2%), headaches (20.4%), and muscle spasms (11.1%). Mean tegoprubart plasma concentrations increased proportionally with increasing dose with a half-life of approximately 24 days. ADA titers were low and circulating levels of tegoprubart were as predicted for all cohorts. Tegoprubart demonstrated dose dependent target engagement associated and a reduction in 18 pro-inflammatory biomarkers in circulation. Tegoprubart appeared to be safe and well tolerated in adults with ALS demonstrating dose-dependent reduction in pro-inflammatory chemokines and cytokines associated with ALS. These results warrant further clinical studies with sufficient power and duration to assess clinical outcomes as a potential treatment for adults with ALS. Clintrials.gov ID:NCT04322149.

A review of recent clinical trials to evaluate disease-modifying therapies in the treatment of cardiac amyloidosis.

Cardiac amyloidosis (CA) is a serious condition that results in infiltrative cardiomyopathy and heart failure with preserved ejection fraction (HFpEF) that is caused by the extracellular deposition of amyloid fibrils within heart tissue. While many important features of CA have been known for years, its prevalence in elderly patients with HF is increasingly being recognized. Plasma cells produce monoclonal immunoglobulin light chains which results in the formation and aggregation of amyloid fibrils that are responsible for AL amyloidosis. CA is classified as originating from either transthyretin (ATTR) or light chain (AL) amyloidosis. ATTR CA may result from a genetic mutation in the TTR gene, which is inherited (ATTRv), or from age-related deposition from wild-type ATTR (ATTRwt). Cardiac involvement in AL amyloidosis is attributed to either of two mechanisms: the extracellular deposition of amyloid fibril in the myocardium, or direct cardiotoxicity from the fibril aggregates. Typing of amyloid fibrils, a critical determinant of therapy, has also improved with wider availability of laser capture and mass spectrometry of histologic specimens. Specific and accurate evaluation of CA is now possible using cardiac magnetic resonance imaging and bone scintigraphy tracers. Survival in CA has improved markedly as novel chemotherapy agents have become available, but challenges remain in advanced disease. Broadening the amyloid-specific therapeutic landscape to include RNA inhibitors, fibril formation stabilizers and inhibitors, and immunotherapeutic targeting of amyloid deposits holds promise and may improve outcomes in systemic and cardiac amyloidoses. Treatment strategies for CA has recently undergone transformative changes, leading to some progress in outcomes for certain patients. Here, we discuss the basic features of CA as well as the emergence of novel, disease-modifying strategies that have been recently evaluated in clinical trials for the treatment of CA.

Clinical trajectories of patients with multiple sclerosis from onset and their relationship with serum neurofilament light chain levels.

Serum neurofilament light chain (sNfL) is a biomarker of neuroaxonal destruction that correlates with acute inflammation (AI) in multiple sclerosis (MS). However, in the treatment era, progression without AI is the main driver of long-term disability. sNfL may provide added value in detecting ongoing axonal damage and neurological worsening in patients without AI. We conducted a prospective three-year study on patients with a first MS relapse to evaluate the basal cut-off value predicting early increased disability unrelated to relapses. sNfL levels and AI presence were measured every 6 months during the first year and the Expanded Disability Status Scale (EDSS) was monitored until the third year. Baseline cohorts were stratified by sNfL levels, using a cut-off derived from patients without AI (absence of clinical relapses, new/enlarging T2 lesions, or gadolinium enhancement in magnetic resonance imaging) at year one. Fifty-one patients were included. A sNfL cut-off of 11 pg/mL predicted sustained neurological worsening independent of AI. Patients exceeding this threshold exhibited features of highly active MS (higher proportion of AI, oligoclonal M bands and higher EDSS). Despite AI ablation, sNfL levels persisted elevated and were significantly associated with increased EDSS at baseline and year 3. Patients with low sNfL and concurrent AI (n = 8) experienced relapses in the optic nerve, brainstem, and spinal cord topographies. sNfL elevation may detect patients with increased disability even when AI is controlled. This may reveal mechanisms associated with early axonal degeneration and help identify patients at higher risk of progression.

Development of imaged capillary isoelectric focusing as a platform mispairing byproduct testing method for asymmetric WuXiBody-based bispecific antibodies

This study explores the application of imaged capillary isoelectric focusing (icIEF) to distinguish and quantify mispairing byproducts in asymmetric WuXiBody-based bispecific antibodies (AsWXbsAbs). Bispecific antibody (BsAb), developed using Knobs-into-Holes (KiH) technology, often result in byproducts such as knob-knob (KK) and hole-hole (HH) homodimers, which share similar sizes with the target BsAb, complicating their separation by traditional methods like size exclusion chromatography-high performance liquid chromatography (SEC-HPLC). Our approach leverages the unique pI differences introduced by substituting the CH1/CL domain with the T cell receptor (TCR) constant domain in AsWXbsAbs. This modification enables icIEF to effectively differentiate between the KK and HH homodimers and the target BsAb. Through the construction and expression of heavy and light chain variants, we validated that the experimental pI values aligned with theoretical predictions, confirming icIEF’s capability in distinguishing these entities. Enrichment of in-process K-related and H-related species was achieved, allowing for high-purity samples necessary for icIEF method development. The method was qualified and showed good specificity and linearity, with a quantitation limit of 4 % for K-related species (R2 = 0.9919) and 1 % for H-related species (R2 = 0.9805). This method was used effectively as an in-process test and release assay, proving its simple and quick utility in multiple AsWXbsAbs projects.

Cumulative Socioeconomic Status Risk is Associated with Greater Increase in Serum Neurofilament Light Chain Levels Among Middle-Aged Black Adults.

This study examined the longitudinal relationship between cumulative socioeconomic status (SES) risk and serum neurofilament light chain (NfL) levels to better understand the association between social factors and a biomarker of neurodegeneration. We used data from the Family and Community Health Study (FACHS), collecting psychosocial and blood data at two waves (2008) and (2019) from 254 Black Americans (43 males and 211 females). Blood samples were analyzed at each wave for serum NfL concentrations. Regression analysis and mixed-effect modeling examined relationships between cumulative SES risk and serum NfL, controlling for covariates and assessing time effects. Utilizing 11-year longitudinal data, serum NfL levels increased with age. Higher cumulative SES risk at baseline correlated with elevated serum NfL at the 11-year follow-up and predicted a greater increase in NfL levels. Clinically, NfL is a sensitive biomarker for axonal injury and neurodegeneration, commonly used to detect early and preclinical stages of conditions such as Alzheimer's disease (AD), multiple sclerosis, and other neurodegenerative disorders. Our results suggest that exposure to cumulative SES risk among Black adults may contribute to elevated levels of NfL, indicating potential early neurodegeneration. Given the established role of NfL in detecting neurodegenerative processes, these findings underscore the importance of interventions that bolster social safety nets and social connectedness to enhance brain health and mitigate neurodegenerative risks.

Monoclonal gammapathies: Epidemiological, immunochemical and etiological analysis of a series of 50 cases

During the period from September 2022 to January 2023, 50 cases of monoclonal gammopathy (GM) were collected at the Avicenne military hospital in Marrakech. The average age of the patients was 62 years. Thirty patients were male and 20 were female. The etiological diagnosis could be established for the 50 observations: 5 were classified as GM of undetermined significance (GMSI), 42 were classified as myeloma, two case of Waldenström's disease and one case of AL amyloidosis. The clinical symptomatology was dominated by bone pain in 78% of patients with a deterioration in general condition in 43%. The most frequently found biological abnormalities were anemia in 62% of patients, renal failure in 48% of patients and 19% had hypercalcemia. A monoclonal peak was found in the electrophoreses of 45 patients (90%), of whom 6 migrated to the beta zone and 39 migrated to the gamma zone. The IgG Kappa isotype was the most frequent with a rate of 56%, followed by IgG Lambda (27%), IgA Kappa (8%), IgA Lambda (3%), IgM Lambda (3%) and lambda free light chains (3%).

Free Kappa light chain in a sample of Egyptian multiple sclerosis patients (a pilot study)

BackgroundMultiple sclerosis is a chronic autoimmune-mediated demyelinating disease of the central nervous system that is usually associated with varying degrees of progressive disability. Free Kappa light chain (FKLC) has attracted growing attention as a significant diagnostic marker of MS. Our aim was to study the diagnostic utility of cerebrospinal fluid free Kappa light chain and related indices in a sample of Egyptian MS patients vs. CSF IgG oligoclonal bands. It was a prospective case–control study of MS patients carried in our hospital during the period from January 2021 till January 2022. Our study carried on 30 patients with multiple sclerosis and other inflammatory neurologic diseases and 20 age and sex matched controls. The study measured FKLC in the CSF and serum sample pairs of patients and control group. Indices calculated using FKLC measured in CSF and serum included; FKLC index, FKLC intrathecal fraction and quotient of FKLC. Indices were used to assess intrathecal synthesis of FKLC considering blood–CSF barrier function. Receiver operating characteristic curve analysis was used to determine diagnostic performance of FKLC and related indices in comparison to CSF–OCB testing.ResultsMeasured FKLC levels as well as its calculated indices have shown statistically significant higher values among MS patients against OIND patients and healthy control group. Both FKLC index and FKLC IF were similarly showing 100% diagnostic sensitivity and 100% diagnostic specificity for MS diagnosis.ConclusionsFKLC biomarkers are proposed to be highly sensitive and easy to detect first-line markers of intrathecal immunoglobulin synthesis with accurate performance and low cost that might prove to be promising diagnostic markers of MS.

Serum neurofilament light chain: a novel biomarker for cardiovascular diseases in individuals without hypertension

Serum neurofilament light chain (sNFL) is a biomarker for axonal injury. Previous studies have linked sNFL levels to cardiovascular risk factors such as diabetes and hypertension, but its association with cardiovascular diseases (CVD) remains unclear. This study aims to explore the association between sNFL and CVD and evaluates its predictive value. Utilizing NHANES 2013–2014 data, this study included 2,035 participants aged ≥ 20 years with measured sNFL quantified using a Siemens immunoassay. CVD was self-reported and included myocardial infarction, stroke, heart failure, coronary heart disease, or angina. Logistic regression models assessed the association between sNFL levels and CVD. The predictive value of sNFL for CVD was evaluated using area under the curve (AUC) and DeLong test. Participants with higher sNFL levels were typically older, male, non-Hispanic white, smokers, and had lower socioeconomic status, higher CVD, hypertension, and diabetes prevalence. Higher sNFL levels were significantly associated with increased odds of CVD (adjusted OR = 1.41, 95% CI: 1.05–1.88). The association was significant in non-hypertensive individuals (OR = 2.72, 95% CI: 1.61–4.62) but not in hypertensive individuals (OR = 1.13, 95% CI: 0.81–1.56). sNFL addition to traditional risk models improved predictive accuracy, especially in non-hypertensive individuals (AUC from 0.827 to 0.856). sNFL levels are significantly associated with CVD in the general population, with a strong predictive value in non-hypertensive individuals. Future longitudinal studies should validate sNFL’s efficacy in various populations and explore the underlying mechanisms of its relationship with hypertension and CVD.

Warning values of serum total kappa/lambda ratio for M-proteinemia

BackgroundTo introduce the serum total kappa/lambda ratio (K/L) in humoral immunity testing reports to improve the detection rate of M-proteinemia.Methods156 M protein-positive and 5464 M protein-negative samples confirmed by serum immunofixation electrophoresis(sIFE) were accumulated from January 2021 to December 2023 in the First Affiliated Hospital of Soochow University and the contents of immunoglobulins (IgG, IgA, IgM, kappa and lambda) were tested by Beckman IMMAGE800. All the samples were divided into two groups by time: the modeling group and the validation group. The K/L values in the modeling group were analyzed by SPSS 27.0 to get the receiver operating characteristic curve (ROC). Furthermore, a more in-depth analysis was conducted to verify the reliability of the optimal cutoff values in the validation group. In addition, the levels of immunoglobulins of another group including 106 patients with definite diagnosis of monoclonal gammopathy ranging from January 2021 to June 2024 were traced back to improve the diagnostic efficiency.ResultsThe optimal cutoff values of K/L were 2.31 and 1.43 corresponding to K-type and L-type M-proteinemia respectively by ROC analysis. The sensitivity and specificity were validated as 76.14% and 77.42%. False positives were mainly found in samples with systemic sclerosis (36.84%), hypohepatia (28.71%) and sicca syndrome (27.27%). While false negatives were mainly found in IgA monoclonal gammopathy (38.39%) and IgM monoclonal gammopathy (28.57%). Combining with the detection rules of IgG, IgA and IgM, the sensitivities for the diagnosis of immunoglobulin light chain amyloidosis(AL) and monoclonal gammopathy of undetermined significance(MGUS) can be increased to 83.33% and 85%.ConclusionsK/L > 2.31 and K/L < 1.43 can be used as warning values for M-proteinemia. In addition, the content of the heavy chain in IgA- or IgM-type M-proteinemia may be considered to improve the detection rate.

Structural insights into epitope-paratope interactions of a monoclonal antibody targeting CEACAM5-expressing tumors

Carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) are overexpressed in some tumor types. The antibody-drug conjugate tusamitamab ravtansine specifically recognizes the A3-B3 domains of human CEACAM5 (hCEACAM5). To understand this specificity, here we map the epitope-paratope interface between the A3-B3 domains of hCEACAM5 (hCEACAM5A3-B3) and the antigen-binding fragment of tusamitamab (tusa Fab). We use hydrogen/deuterium exchange mass spectrometry to identify the tusa Fab paratope, which involves heavy chain (HC) residues 101–109 and light chain residues 48–54 and 88–104. Using surface plasmon resonance, we demonstrate that alanine variants of HC residues 96–108 abolish binding to hCEACAM5, suggesting that these residues are critical for tusa-Fab–antigen complex formation. The cryogenic electron microscopy structure of the hCEACAM5A3-B3- tusa Fab complex (3.11 Å overall resolution) reveals a discontinuous epitope involving residues in the A3-B3 domains and an N-linked mannose at residue Asn612. Conformational constraints on the epitope-paratope interface enable tusamitamab to target hCEACAM5A3-B3 and distinguish CEACAM5 from other CEACAMs.

Comparison of Serum and Cerebrospinal Fluid Neurofilament Light Chain Concentrations Measured by Ella™ and Lumipulse™ in Patients with Cognitive Impairment.

Neurofilament light chain proteins (NfLs) are considered a promising biomarker of neuroaxonal damage in several neurological diseases. Their measurement in the serum and cerebrospinal fluid (CSF) of patients with dementia may be especially useful. Our aim was to compare the NfL measurement performance of two advanced technologies, specifically the Ella™ microfluidic platform and the Lumipulse™ fully automated system, in patients with cognitive disorders. Thirty subjects with neurodegenerative cognitive disorders (10 with Alzheimer's Disease, 10 with Frontotemporal Dementia, and 10 with non-progressive Mild Cognitive Impairment) seen at the Cognitive Neurology Clinic of Modena University Hospital (Italy) underwent CSF and serum NfL measurement with both the Ella™ microfluidic platform (Bio-Techne, Minneapolis, MN, USA)) and the Lumipulse™ fully automated system for the CLEIA (Fujirebio Inc., Ghent, Belgium). Correlation and regression analyses were applied to assess the association between NfL concentrations obtained with the two assays in CSF and serum. The Passing-Bablok regression method was employed to evaluate the agreement between the assays. There were high correlations between the two assays (r = 0.976, 95% CI. 0.950-0.989 for CSF vs. r = 0.923, 95% CI 0.842-0.964 for serum). A Passing-Bablok regression model was estimated to explain the relationship between the two assays, allowing us to switch from one to the other when only one assay was available. We found a good degree of correlation between the two methods in patients with neurocognitive disorders. We also established a method that will allow comparisons between results obtained with either technique, allowing for meta-analyses and larger sample sizes.

Rethinking antisense oligonucleotide therapeutics for amyotrophic lateral sclerosis.

Antisense oligonucleotides, which are used to silence target genes, are gaining attention as a novel drug discovery modality for proteinopathies. However, while clinical trials for neurodegenerative diseases like amyotrophic lateral sclerosis have been conducted in recent years, the results have not always been favorable. The results from a Phase III trial of the antisense oligonucleotide, that is, tofersen, which targets SOD1 mRNA, showed decreased levels of cerebrospinal fluid SOD1 and plasma neurofilament light chain but no improvements in primary clinical endpoint. Moreover, case reports pertaining to patients with amyotrophic lateral sclerosis carrying FUS and C9orf72 mutations who received antisense oligonucleotide-based treatments have demonstrated a notable reduction in the targeted protein (thus providing the proof of mechanism) but with no discernible clinical benefits. There are several possible reasons why antisense oligonucleotides knockdown fails to achieve proof of concept, which need to be addressed: on-target adverse effects resulting from the loss of function of target gene and irreversible neuronal death cascade due to toxic protein accumulation, among other factors. This review provides an overview of the current status and discusses the prospects of antisense oligonucleotides treatment for amyotrophic lateral sclerosis.

Alterations in Hurler-Scheie Syndrome Revealed by Mass Spectrometry-Based Proteomics and Phosphoproteomics Analysis.

Hurler-Scheie syndrome (MPS IH/S), also known as mucopolysaccharidosis type I-H/S (MPS IH/S), is a lysosomal storage disorder caused by deficiency of the enzyme alpha-L-iduronidase (IDUA) leading to the accumulation of glycosaminoglycans (GAGs) in various tissues, resulting in a wide range of symptoms affecting different organ systems. Postgenomic omics technologies offer the promise to understand the changes in proteome, phosphoproteome, and phosphorylation-based signaling in MPS IH/S. Accordingly, we report here a large dataset and the proteomic and phosphoproteomic analyses of fibroblasts derived from patients with MPS IH/S (n = 8) and healthy individuals (n = 8). We found that protein levels of key lysosomal enzymes such as cathepsin D, prosaposin, arylsulfatases (arylsulfatase A and arylsulfatase B), and IDUA were downregulated. We identified 16,693 unique phosphopeptides, corresponding to 4,605 proteins, in patients with MPS IH/S. We found that proteins related to the cell cycle, mitotic spindle assembly, apoptosis, and cytoskeletal organization were differentially phosphorylated in MPS IH/S. We identified 12 kinases that were differentially phosphorylated, including hyperphosphorylation of cyclin-dependent kinases 1 and 2, hypophosphorylation of myosin light chain kinase, and calcium/calmodulin-dependent protein kinases. Taken together, the findings of the present study indicate significant alterations in proteins involved in cytoskeletal changes, cellular dysfunction, and apoptosis. These new observations significantly contribute to the current understanding of the pathophysiology of MPS IH/S specifically, and the molecular mechanisms involved in the storage of GAGs in MPS more generally. Further translational clinical omics studies are called for to pave the way for diagnostics and therapeutics innovation for patients with MPS IH/S.

Protective effect of betaine supplementation in low-met diet against Aeromonas hydrophila-induced intestinal injury in grass carp (Ctenopharyngodon idella)

This study evaluated the effect of supplemental betaine in low-methionine (Met) diet concerning the regulatory role of bacteria-induced intestinal injury in fish. 540 grass carp (Ctenopharyngodon Idella) (210 ± 0.68 g) were selected and randomly divided into 6 groups, which contained a reference group fed with the diet supplemented with DL-Met (3.1 g kg−1 diet) and 5 groups fed on the diets added with increasing levels of betaine (0–6.4 g kg−1 diet) for 60 days. Then, a 14-day Aeromonas hydrophila challenge was conducted. Compared with BET0 group, results indicated that appropriate betaine supplementation (1) enhanced antioxidant enzymes activities (except glutathione S-transferase pi-1 (GSTP1) and copper zinc superoxide dismutase (CuZnSOD) and glutathione (GSH) contents, and NF-E2-related-factor 2 (Nrf2) protein nuclear translocation, while reduced reactive oxygen species (ROS), and representative oxidative damage markers; (2) up-regulated the transcription abundance of anti-apoptosis-related molecules while reduced DNA-ladder occurrence and the transcription levels of pro-apoptosis-related genes; (3) down-regulated the transcription of tight junction-related proteins (such as zonula occludens-1 (ZO-1) etc.) in fish intestines. Furthermore, correlation analysis revealed that feeding betaine ameliorating the oxidative damage, apoptosis and tight junction breakdown was possibly related to intestinal Nrf2, p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinases (JNK), and myosin light chain kinase (MLCK) signaling, respectively. According to the regression analysis for intestinal ROS abundance, claudin-b and caspase-2 transcription, the appropriate betaine supplementations were estimated to be 3.82, 3.98, and 3.62 g kg−1 diet, respectively. Notably, betaine has the potential to spare part Met and the efficacy of betaine relative to Met was 206.67 % based on intestinal ROS contents in grass carp (210–776 g).

VRAC Complex Modulates Mechano-Electrical Signal Responses in Human Airway Smooth Muscle Shortening.

Leucine-rich repeat containing 8A (LRRC8A) is an obligatory constituent of the volume-regulated anion channel (VRAC) that is fundamental to a wide range of biological processes, including regulating cell size, proliferation, and migration. Here we explored the physiological role for VRAC in excitation-contraction (E-C) coupling and shortening of human airway smooth muscle (HASM). In HASM cells, pharmacological inhibition of VRAC with DCPIB (0.1-10 μM) markedly attenuated swell-activated Cl- conductance and contractile agonist (histamine or carbachol)-induced cellular stiffening as measured by single-cell patch clamp and optical magnetic twisting cytometry, respectively. In addition, HASM cells treated with DCPIB or transfected with LRRC8A-targeting siRNA showed reduced agonist-induced phosphorylation of protein kinase B (AKT), paxillin, myosin phosphatase target subunit 1 (MYPT1), and myosin light chain (MLC). Consistent with the changes of these E-C coupling effectors, DCPIB appreciably decreased agonist-induced small airways narrowing in human precision-cut lung slices (hPCLS). Taken together, our findings shed a new light on the mechanistic link between HASM shortening and regulatory volume decrease via LRRC8A, revealing a previously unrecognized nodal point for modulation of the E-C coupling and acute airways constriction.

Prevalence and prognostic significance of restriction versus systolic dysfunction in patients with transthyretin and light chain cardiac amyloidosis

Abstract The tenet of cardiac amyloidosis (CA) as a paradigm of heart failure with restrictive ventricular physiology and preserved systolic function has come under scrutiny. Thus, we aimed to evaluate the prevalence and clinical significance of left ventricular (LV) systolic dysfunction versus restriction in a large real-world cohort with CA, assessed at the time of diagnosis. Methods This is a multicenter retrospective analysis including 540 transthyretin (ATTR)-CA and 280 light chain (AL)-CA. Patients were divided into 3 phenotypes: 1) preserved LV function: LV ejection fraction (EF) ≥50% associated with grade 0/I diastolic dysfunction; 2) restriction: LV-EF≥50% associated with grade II/III diastolic dysfunction; 3) systolic dysfunction: LV-EF&amp;lt;50% irrespective of diastolic function. We analysed progression from preserved LV function towards the other two phenotypes and their survival. Results In ATTR-CA, prevalence of preserved LV function was 27%, restriction was 44% and systolic dysfunction was 28%. Among patients with preserved LV function, annual conversion rate to restriction was 24% and to systolic dysfunction was 17%. At 3 years, survival free from all-cause mortality was 88%, 76% and 63% respectively (figure A). In AL-CA, prevalence of preserved LV function was 30%, restriction was 49% and systolic dysfunction was 20%. Among patients with preserved LV function, annual conversion rate to restriction was 28% and to systolic dysfunction was 8%. At 3 years, survival free from all-cause mortality was 56%, 39% and 29% respectively (figure B). Conclusions Restriction was the presenting phenotype in less than half of patients, while systolic dysfunction in approximately one quarter. The annual rate of progression form preserved LV function towards restriction or systolic dysfunction was high. In ATTR systolic dysfunction was associated with worse outcome, compared to restriction; in AL both restriction and systolic dysfunction were associated with equally ominous outcome.