Commercial Assay Research Articles

Analytical and clinical evaluation of a duplex RT-qPCR assay for the detection and identification of o’nyong-nyong and chikungunya virus

The mosquito-borne alphavirus o’nyong-nyong virus (ONNV) has proven its potential to cause major human outbreaks. On the African continent, ONNV causes unspecific febrile illness and co-circulates with the close relative chikungunya virus (CHIKV). The true scale of ONNV burden is poorly understood in Africa, because of the scarce availability of molecular in-house and commercial assays, strong cross-reactivity between ONNV and CHIKV in serological assays and a lack of surveillance. We designed a new RT-qPCR assay targeting the E1 gene for the detection of ONNV that can be used in monoplex or in duplex format, combined with a previously published CHIKV monoplex assay targeting the nsp1. The lower limit of detection with 95% positivity rate was determined to be <10 RNA copies/µL in monoplex and duplex format for both ONNV and CHIKV. Both monoplex assays and the duplex assay proved to be linear within the tested range of approximately 108 to 102 RNA copies/µl, and showed 100% specificity against a wide panel of arbovirus supernatants as well as several other pathogens in clinical samples. Testing of CHIKV positive serum and ONNV spiked plasma samples confirmed the suitability of the assays in a clinical setting. The new assays provide a robust tool for molecular ONNV as well as ONNV/CHIKV simultaneous detection and may contribute to clarify the true burden of the two viruses, to improve arbovirus surveillance and to strengthen epidemics preparedness in Africa.

An iridium(III) complex-based luminogenic probe for high-throughput screening of hydrogen sulfide donors in living cells.

The scarcity of suitable high-throughput screening technology for hydrogen sulfide (H2S) donors has hampered the discovery of H2S donors. In this study, a long-lived cyclometalated iridium complex was rationally designed as a mitochondria-targeted H2S probe to monitor the real-time dynamic change of H2S. By using the time-resolved emission spectroscopy (TRES) technique, an anti-interference high-throughput screening system was developed to monitor H2S in living cells with decreased false negative results. As a proof-of-concept, three natural products were identified as potential H2S donors from a natural product library using the developed TRES probe. Notably, the discovery of allicin and diallyl trisulfide demonstrated the feasibility of this screening platform, while garlic-derived allyl methyl sulfide was explored as a H2S donor candidate. The results were further validated by a commercial assay. We anticipate this high-throughput platform could facilitate the discovery of H2S donors by discriminating the endogenous interfering fluorescence from biological systems.

Serological and Molecular Investigation of Infectious Laryngotracheitis Virus in Chickens from Robe Town, Southeastern Ethiopia

Infectious laryngotracheitis virus (ILTV) is responsible for avian infectious laryngotracheitis (ILT), a highly contagious acute respiratory disease affecting chickens. However, there is limited information on ILTV and its distribution in Ethiopia, particularly in the southeastern region. The aim of this study was to establish the serological prevalence and molecular evidence in commercial and backyard chickens from Robe town, Southeastern Ethiopia. A cross-sectional study was conducted between December 2021 and June 2022, collecting 240 serum samples from randomly selected chickens belonging to eight kebeles (farms) using systematic random sampling. ILTV-specific antibodies were detected using a commercial indirect enzyme-linked immunosorbent assay (ELISA). From 240 serum samples, 26.7% were positive for ILTV antibodies. Logistic regression analysis identified the type of poultry farm (backyard) and the introduction of chickens from other farms as potential risk factors associated with ILTV exposure. Tracheal tissue and oropharyngeal and tracheal swabs were collected from suspected chickens for isolation and molecular detection. A total of six samples were successfully isolated in embryonated eggs (40%), with four of them verified with a specific PCR. These findings documented the presence of ILTV in the study area, which needs further insight to fully understand the actual spread of ILTV and quantify the damage caused to the poultry sector.

Harmonized Tubular Maximum Phosphate Reabsorption per Glomerular Filtration Rate (TmP/GFR) reporting in adults and children in Australia and New Zealand

Abstract Tubular maximum phosphate reabsorption per glomerular filtration rate (TmP/GFR) is a key diagnostic test for renal phosphate wasting. However, there is a lack of international consensus regarding the reporting of age-related reference intervals. The TmP/GFR Harmonization Working Group, formed by The Australasian Association for Clinical Biochemistry and Laboratory Medicine and The Australian and New Zealand Bone and Mineral Society, aimed to evaluate analytical differences amongst commercial creatinine and phosphate assays, harmonize age-specific cut-offs and compare the ANZBMS TmP/GFR online calculator with existing products. A total of 11 360 results from The Royal College of Pathologists of Australasia Quality Assurance Programs were analyzed to assess creatinine and phosphate assay performance amongst five In Vitro Diagnostic (IVD) companies. Ortho-Clinical Diagnostics analyzers had a positive bias of up to 32% for serum phosphate and up to 29% for TmP/GFR. The other IVD companies produced comparable results and are suitable for harmonized reference intervals. To date, the AACB-ANZBMS TmP/GFR online calculator is the only validated Isotope Dilution Mass Spectrometry-creatinine aligned tool which caters for both pediatric and adult individuals, providing automatic interpretive comments to aid clinicians managing patients with hypophosphatemia.

Development and Validation of an Indirect and Blocking ELISA for the Serological Diagnosis of African Swine Fever

African swine fever (ASF) is an economically devastating viral disease of pigs caused by the ASF virus (ASFV). The rapid global spread of ASF has increased the demand for ASF diagnostics to be readily available and accessible. No commercial ASF enzyme-linked immunosorbent assay (ELISA) kits are manufactured and licensed in North America. Here, we report the development of two serological diagnostic assays, a blocking ELISA (bELISA) based on ASFV glycoprotein p54 and an indirect ELISA (iELISA) based on ASFV glycoproteins p54 and p72. The assays showed high sensitivity and specificity and detected anti-ASFV antibodies in serum samples from experimentally infected animals as early as 8 days post-infection. The two assays were produced commercially (AsurDx™ bELISA and iELISA) and subjected to extensive validation. Based on data from a set of characterized reference sera, the prototype commercial assays, while maintaining 100.00% specificity, showed 97.67% (AsurDx™ bELISA) and 83.72% (AsurDx™ iELISA) sensitivity. Both prototype assays detected anti-ASFV antibodies in serum samples collected from pigs experimentally infected with multiple ASFV strains and field samples collected from sick, recovering, and vaccinated animals. The two commercially available assays can be used in routine ASF diagnostics, serological surveys, and for evaluating serological responses to ASF vaccine candidates.

Sex ratios of olive ridley sea turtles in the North Pacific high seas: implications for climate change research

Size-class distributions and sex ratio data provide critical information to assess the demography and reproductive potential of animal populations, such as sea turtles. Sea turtle sex is determined by incubation temperature, whereby warmer temperatures during a certain period of embryonic development produce more female hatchlings. Whereas hatchling sex ratios have been well-studied, sex ratios of sea turtle foraging aggregations are less known for most populations. Here we report on sex ratios of immature and mature olive ridley sea turtles Lepidochelys olivacea in the Eastern Tropical Pacific (ETP) and Central North Pacific (CNP) based on blood plasma hormone analysis, refined with Bayesian modeling, or gonad examination. Our findings established that (1) the commercial enzyme-linked immunosorbent assay used in the present study was appropriate to analyze testosterone concentration in olive ridley blood plasma to determine foraging ground sex ratios (via a Bayesian model); (2) size-at-maturity is generally larger in males than females in the ETP; (3) the overall sex ratio among all turtles was 1.2F:1.0M; and (4) the sex ratio of smaller-sized immature turtles from both study regions was female-biased (ETP, 1.6F:1.0M and CNP, 2.1F:1.0M). These are the first sex ratio estimates for olive ridleys foraging in the high seas of the North Pacific Ocean. The data can inform population models for species conservation, particularly those that contribute to the development of conservation plans that consider climate change projections.

Expression of Five Important Biomarkers in Non-small Cell Lung Cancer: MicroRNAs-128, miR-335-5p, miR-1254, VEGF, and K-RAS

Background: Lung cancers, such as non-small cell lung cancer (NSCLC), are the most common malignancy and leading cause of cancer-related death worldwide. MicroRNAs (miRNAs) play a role in the occurrence of lung cancer by targeting both tumor suppressor genes and oncogenes. Among them, miR-128, miR-335-5p, and miR-1254 are mainly reported to function in regulating lung cancer cell behavior. Objectives: The aim of the study was to investigate the existence and expression levels of miRNA-128, miR-335-5p, and miR-1254 as well as mRNA and protein expression levels of VEGF and mRNA expression levels of K-RAS in both peripheral blood and cancerous tissue of NSCLC patients compared to the healthy subjects. Methods: Blood and tissue samples were collected from 50 healthy donors and 50 NSCLS patients. The serum level of VEGF was measured using the commercial enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of K-RAS and VEGF, as well as the expression of miRNA-128, miR-335-5p, and miR-1254, were determined, using real-time PCR. Results: Lower mRNA expression levels of miRNA-128, miR-335-5p, and miR-1254, as well as higher mRNA expression levels of VEGF and K-RAS, were detected in both peripheral blood and tissue samples from NSCLC patients compared to those of the healthy subjects. The VEGF protein levels in the peripheral blood of the patients were also found to be significantly lower than those in the healthy subjects. Conclusions: The findings from this study suggest that miR-335-5p, miR-1254, and miR-128, may contribute to the pathogenesis and tumorigenesis of NSCLC at least in part by modulation of proliferation, migration, and angiogenesis via targeting VEGF and K-RAS signaling pathways. K-RAS and VEGF may be target genes for miR-335-5p, miR-1254, and miR-128 in NSCLC patients.

At the mercy of the AI algorithm - discrepant PCR results.

As pathogen molecular diagnostics technology develops, the software analysis of polymerase chain reaction (PCR) sigmoidal curves, crossing threshold (Ct) values and the limit of nucleic acid detection for that assay, is not always available when reporting test results. These are critical components in interpreting results and can affect the management of patients. Our view is that all commercial assay providers must ensure users, as they can with laboratory developed tests, are able to see the curve and Ct value for all samples. Some examples demonstrating this principle are included. Regulatory bodies have a key role to play.

Update on Mpox Management: Epidemiology, Vaccines and Therapeutics, and Regulatory Changes.

Mpox, caused by the monkeypox virus (MPXV), is categorized into two primary clades: Clade I and Clade II, with notable outbreaks linked to Clade IIb. Historically endemic in Africa, recent years have seen significant global spread. The World Health Organization (WHO) declared mpox a Public Health Emergency of International Concern in August 2024, highlighting the emergence of Clade Ib outside Africa and the broadening demographic impact of the outbreak. This review updates the current status of mpox vaccines and treatments, including their safety and effectiveness. There are two US Food and Drug Administration (FDA)-approved vaccines for the prevention of mpox disease, JynneosTM and ACAM2000®. The JynneosTM vaccine, recommended for high-risk individuals, has seen limited uptake despite its efficacy in preventing disease. Tecovirimat, while FDA-approved for smallpox and available in the European Union for mpox, has shown mixed results in recent trials, with new data suggesting limited effectiveness in Clade I infections and emergence of new mutations with resistance to this drug. Brincidofovir and Vaccinia Immune Globulin Intravenous offer additional treatment options, particularly for severe cases, although their use is constrained by regulatory and logistical challenges. Furthermore, the WHO recently approved the first commercial molecular assay, the Alinity m MPXV assay by Abbott Molecular Inc., for emergency use-an essential step in expanding testing capacity in regions experiencing mpox outbreaks. These updates underscore the critical need for continued research to enhance therapeutic outcomes and adapt public health strategies. Ensuring equitable access to vaccines, treatments, and diagnostics remains a significant challenge as the global community responds to the evolving mpox situation.

Kinetics of Hepatitis B Virus replication in anti-HBc positive/HBsAg-negative people with HIV switching to Tenofovir sparing therapy

Objectives: To unravel the still unexplored HBV-replicative kinetics in antiHBc-positive/HBsAg-negative people-with-HIV (PWH) suspending TDF/TAF. Methods: 101 antiHBc-positive/HBsAg-negative PWH switching to TDF/TAF-sparing therapy were included. Serum HBV-DNA and HBV-RNA were quantified by droplet-digital-PCR at switching (T0), within 12-months (T1) and 12-24 months post-switch (T2). Results: At T0, 33.7% had cryptic HBV-DNA (undetected by commercial assays, median[IQR]:2[1-5]IU/ml) and 22% were positive to HBV-RNA alone (median[IQR]:4[3-4]IU/ml), indicating an active HBV-reservoir despite HBsAg-negativity and TDF/TAF-pressure. Notably, antiHBs-titer<100mIU/ml independently correlated with cryptic HBV-DNA at T0 (OR[95%CI]:2.6[1.02-6.5], P=0.04). After TDF/TAF-withdrawal, the rate of PWH achieving HBV-DNA>10IU/ml increased from 12.9% at T1 to 42.6% at T2 (P<0.0001). Likewise, a rise from 2% to 11% was observed for HBV-DNA>100IU/ml (P=0.02); median(IQR) HBV-DNA: 579(425-770)IU/ml. Notably, HBV-DNA>10IU/ml at T2 occurred in 70% of PWH with cryptic HBV-DNA, in 38.5% with HBV-RNA alone and in 25% negative to both HBV-markers at T0 (P=0.01). Cryptic HBV-DNA at T0 and lower nadir CD4+T-cell-count independently predicted HBV-DNA>10IU/ml at T2 (OR[95%CI]:8.2[1.7-40.6], P=0.01; OR[95%CI]:8.1[1.3-52.1], P=0.03). Lastly, persistent HBV-DNA positivity was independently associated with a reduced CD4+T-cell recovery at T2 (OR[95%CI]:0.07[0.01-0.77], P=0.03). Conclusions: This study underlines the importance to regularly monitor antiHBc-positive/HBsAg-negative PWH undergoing TDF/TAF-sparing regimen and the role of highly-sensitive HBV markers in optimizing their management.

An antibody nanopore-enabled microsensor for detection of osteoprotegerin

This paper introduces an antibody-based nanopore thin film sensor for detecting osteoprotegerin (OPG) in buffer solutions and serum samples, offering significant improvements over current commercial enzyme-linked immunosorbent assay kits in terms of cost, specificity, and selectivity. Capable of detecting OPG concentrations as low as 0.25 pg ml−1—far below the limits of traditional lab equipment—this sensor requires only about 1 μl of serum for effective measurement. The utilization of reference sensors helps reduce non-specific binding, enhancing the sensor’s accuracy. Its affordability and operational simplicity make it ideal for point-of-care monitoring of OPG levels in real-time patient care.

Cattle, sheep, and goat humoral immune responses against SARS-CoV-2

Following the emergence of SARS-CoV-2 in late 2019, several species of domestic and wild animals have been found to be susceptible to SARS-CoV-2 infection through experimental inoculation and animal surveillance activities. Detection of SARS-CoV-2 specific antibodies in animals is an important surveillance tool since viral shedding in animals can only be detected for a short period of time. In this study, convenience serum samples were collected from 691 cattle, 698 sheep, and 707 goats from several regions in the United States, between 2019 to 2022. The samples were evaluated for the presence of SARS-CoV-2 specific antibodies using two commercial enzyme-linked immunosorbent assays (ELISA); one based on the inhibition of the SARS-CoV-2 receptor-binding domain (sVNT) and the other based on the nucleocapsid protein (N-ELISA) of SARS-CoV-2. Positive samples from the sVNT were additionally evaluated using a conventional virus neutralization test (VNT) employing the Wuhan-like SARS-CoV-2 USA/WA1/2020 isolate. Our results indicate that ∼1% (6/691) of cattle, ∼2% (13/698) of sheep, and ∼2.5% (18/707) of goat serum samples were positive when using the sVNT, whereas ∼4% of cattle (25/691) and sheep (27/698), and 2.5% (18/707) of goat serum samples tested positive with the N-ELISA. None of the sVNT positive cattle, sheep, or goat serum samples had detectable neutralizing antibody activity (<1:8) against the SARS-CoV-2 USA/WA1/2020 isolate by the VNT. Our results indicate low seropositivity in cattle, sheep, and goats in the U.S., indicating the importance to continue monitoring for SARS-CoV-2 prevalence in animal species that are in close contact with humans.

Composition of cardiac troponin release differs after marathon running and myocardial infarction

ObjectivesElevations of cardiac troponin T (cTnT) levels are common after strenuous exercise. We assessed whether the composition of cTnT release after marathon race differs from that of acute myocardial infarction (MI).MethodsTroponin composition was analysed in plasma samples taken from 45 runners after marathon race and from 84 patients with type 1 MI. The concentration of long cTnT (intact and mildly fragmented cTnT) was measured with a novel upconversion luminescence immunoassay, total cTnT with a commercial high-sensitivity cTnT assay, and the ratio of long to total cTnT (troponin ratio) was determined as a measure of troponin fragmentation.ResultsTotal cTnT exceeded the upper reference limit (&gt;14 ng/L) in 37 (82%) runners. Troponin ratio was lower in runners ((IQR) 0.17 (0.11–0.24) vs 0.62 (0.29–0.96), p&lt;0.001). With increasing troponin release the troponin ratio decreased (r=−0.497, p&lt;0.001) in marathon runners and the concentration of long cTnT remained in all runners below 8.4 ng/L. In contrast to marathon runners, troponin ratio increased (r=0.565, p&lt;0.001) with the increase of cTnT release in patients with MI. The median total and long cTnT concentrations were lower in marathon runners than in patients with MI (25 ng/L vs 835 ng/L and 4.1 vs 385 ng/L, p&lt;0.001 for both).ConclusionIn contrast to type 1 MI, only a small fraction of circulating cTnT exists as intact cTnT or long molecular forms after strenuous exercise and the difference in troponin composition is more pronounced in runners with higher troponin release.Trial registration numberNCT06000930.

Xylopia parviflora (A. rich.) benth. Mitigates anxiety behavior and chronic mild stress-induced depression-like behavior in mice: The involvement of biogenic amine neurotransmitters, cyclooxygenase-2 and stress biomarkers in its antidepressant activity

BackgroundXylopia parviflora is a novel botanical in Modern Chinese Medicine that contains bioactive constituents including alkaloids, flavonoids, and terpenoids, which are the pharmacologically active components in various Chinese herbal formulations such as Coptis chinensis (alkaloid-rich herbs), Ginkgo biloba (flavonoid-rich herbs) and Artemisia annua (terpenoid-rich herbs). ObjectiveThis investigation sought to evaluate the anxiolytic and antidepressant-like effects of the hydroethanol leaf extract of Xylopia parviflora using mouse models. We elucidated the roles of noradrenaline, serotonin, cyclooxygenase-2, and reactive oxidative species in mediating its antidepressant effects, providing a fresh perspective on the pharmacological activity of Xylopia parviflora. MethodsThe acute toxicity of XPE was assessed following OECD guideline 420. Established behavioral tests were used to evaluate the anxiolytic (including the hole-board, open field, elevated plus maze, and light/dark exploration assessments) and antidepressant (encompassing the forced swim and tail suspension tests) effects of the extract. Mice received treatments of distilled water (10 mL/kg, serving as the negative control), fluoxetine (20 mg/kg, acting as the reference medication), and XPE (at doses of 50, 100, and 200 mg/kg). The concentrations of noradrenaline, serotonin, and COX-2 within the brain tissue were quantified using ELISA kits. The levels of antioxidant biomarkers were evaluated using standardized commercial assay kits. ResultsThe oral/intraperitoneal LD50 for the extract was established at 2000 mg/kg. In the behavioral assessments designed to measure anxiolytic effects, XPE significantly mitigated anxiety levels in mice, as evidenced by an increase in exploratory behaviors (including head dips, sectional crossings, general square crossings, rearing, and assisted rearing) and an increased time spent in the brightly illuminated compartments. Concerning the antidepressant evaluations, XPE significantly reduced depression-like behaviors in mice, which was indicated by an increased latency to immobility and a decrease in the duration of immobility. XPE was found to modulate noradrenaline and serotonin transmissions, attenuate oxidative species, and inhibit COX-2 activity. ConclusionThe findings above demonstrate that Xylopia parviflora possesses anxiolytic and antidepressant-like activities. The antidepressant property of XPE, as revealed in this study, may be attributable to the enhancement of biogenic amines (specifically noradrenaline and serotonin), the suppression of oxidative species, and the inhibition of COX-2 activity.

Emerging zooanthroponotic risks: Detection of the human norovirus GII.4 Sydney[P31] strain in a domestic dog in Brazil

Recent increases in zoonotic diseases underscore the integration of companion animals into urban environments, posing complex transmission risks and highlighting the necessity of One Health approaches. Respiratory and enteric viruses have been consistently linked to interspecies transmission between humans and animals. This study aimed to assess the circulation of human noroviruses (NoV), human adenoviruses (HAdV), enteroviruses (EV), parechoviruses (PeV-A), human bocaviruses (HBoV), hepatitis A (HAV) and E viruses (HEV), Influenza A and B viruses (Flu A/B), respiratory syncytial virus (RSV), and SARS-CoV-2 in domestic dogs and cats in Brazil to understand potential zooanthroponosis risks. Between 2012 and 2021, 600 fecal samples from dogs and cats (516 and 84, respectively) were collected at small animal clinics in São Paulo state, Brazil. The specimens underwent in-house qPCR screening for HBoV and HAdV, while EV, PeV-A, NoV, and HEV were tested using in-house RT-qPCR. SARS-CoV-2, Flu A/B, and RSV were investigated with a commercial RT-qPCR kit assay. HAV detection utilized conventional nested (RT)-PCR. Positive samples were sequenced for molecular characterization and phylogenetic analysis. NoV was detected in 0.2 % (1/600) of the animals, while all other investigated viruses tested negative. The NoV-positive sample, collected in 2012 from a pet dog, was identified as genotype GII.4_Sydney[P31]. The Dog/BRA/2012/GII.4_Sydney[P31]/IAL-M21 strain exhibited a close genetic relationship to Brazilian human and environmental NoV GII.4_Sydney[P31] strains, with 98.1–99.2 % nucleotide similarity in ORF1 and 99.2–99.6 % in ORF2 sequences, suggesting interspecies transmission. Pet dogs are frequently exposed to human fecal-borne viruses, highlighting the potential for zooanthroponotic transmission due to their close interaction with humans in shared environments. There is an urgent need to enhance surveillance studies in companion animals to better understand the implications of detecting human NoV strains in pets, as NoV could potentially act as a reverse zoonotic disease in households, animal hospitals, or shelters worldwide.

On-Chip NADH Detection in Multicellular Models Using an AlGaN/GaN Photodetector Array with Enhanced Sensitivity.

Nicotinamide adenine dinucleotide (NAD) is a pivotal coenzyme, existing in its oxidized form (NAD+) and reduced form (NADH). Both are essential in cellular redox reactions and are implicated in energy production and cancer. Current NADH detection methods often involve complex optical measurements. We propose a miniaturized, on-chip photoelectric sensor array using AlGaN/GaN two-dimensional electron gas (2DEG) photodetectors for NADH quantification. The device exhibits an ultralow dark current and ultrahigh UV light responsivity, enabling sensitive NADH detection. By exploiting the absorbance disparity between NADH and NAD+, our sensor achieves rapid, sensitive detection, surpassing commercial assays. It effectively detects NADH levels in 3D multicellular models, promising cancer screening and monitoring. This sensor platform offers a significant advancement in NADH quantification, with the potential for high-throughput testing and point-of-care diagnostics. Our study presents an efficient approach for NADH sensing, addressing the need for rapid and sensitive detection methods in biomedical research and clinical practice.

Comparison of Four Chimeric Antigens and Commercial Serological Assays for the Diagnosis of Trypanosoma cruzi Infection

Chagas disease (CD), a neglected tropical disease caused by Trypanosoma cruzi, is a significant public health issue particularly in Latin America, affecting millions worldwide. Diagnosis is a challenge owing to the genetic diversity of T. cruzi and the complexities involved in selecting antigens for the detection of anti–T. cruzi antibodies. This study evaluated four chimeric recombinant antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) designed to enhance diagnostic accuracy by addressing assay variability. We compared the diagnostic performance of these chimeric antigens using indirect ELISA as a diagnostic platform, with three commercial serological assays in Brazil, analyzing 100 serum samples from individuals with confirmed CD and 86 from non-infected controls. The results revealed that all assays and antigens demonstrated an area under the receiver operating characteristic curve of 100%, signifying their exceptional ability to distinguish between CD-positive and CD-negative samples. Notably, the chimeric antigens achieved 100% sensitivity, specificity, accuracy, and kappa index, equaling or surpassing the commercial assays. This research highlights the efficacy of IBMP chimeric antigens as reliable diagnostic tools for CD, suggesting their potential integration into commercial diagnostic platforms to enhance the accuracy and reliability of CD detection.

Insulin-like growth factor binding protein 2 predicts course of concomitant right-ventricular dilation and tricuspid regurgitation after transcatheter edge-to-edge mitral valve repair

Abstract Aims Right ventricular (RV) dilation and secondary tricuspid regurgitation (TR) are highly prevalent comorbidities in patients with mitral regurgitation and are associated with a worse prognosis. TR improvement after successful transcatheter edge-to-edge mitral valve repair (M-TEER) is reported regularly, however specific factors contributing to the recovery of RV function and TR after M-TEER are poorly understood. Particularly the role of serum biomarkers in this context is unclear. We aimed to identify specific biomarkers associated with the course of concomitant RV dilation and TR after M-TEER. Methods and Results We prospectively included 242 patients undergoing M-TEER at our center and obtained pre-procedural blood samples for biomarker analysis. A commercial multiplex protein assay (Cardiovascular III, Olink, Uppsala, Sweden) was used to quantify expression levels of 92 defined biomarkers. We then analyzed differences in biomarker expression between patients with and without right ventricular reverse remodeling (RVRR) as defined by improvement of concomitant TR by at least one grade and/or downsizing of the basal RV diameter of at least 10%. 242 patients were included in this analysis, 94 had no/mild concomitant TR at baseline, 148 had moderate/severe TR. RV diameters correlated with TR severity and were significantly larger in patients with moderate/severe TR. At baseline, expression of numerous cardiometabolic biomarkers was significantly higher in patients with moderate/severe TR. These included NT-proBNP (1.9-fold, p &amp;lt; 0.001), matrix metalloproteinase 2 (1.4-fold, p &amp;lt; 0.001) as well as insulin-like growth factor binding proteins 1 (1.7-fold, p &amp;lt; 0.001), -2 (1.3-fold, p = 0.001) and -7 (1.4-fold, p &amp;lt; 0.001). Follow-up analysis was performed in patients with initial moderate/severe TR. The course of TR and RV dimensions three months after M-TEER could be assessed in 99 patients (56 with moderate TR, 43 with severe TR). RVRR had occurred in 50 patients (50.5%). Patients without RVRR had a higher prevalence of chronic pulmonary disease (24.5 vs. 2.2%, p &amp;lt; 0.001). No further differences in clinical characteristics were found. Specifically, RV diameter, systolic pulmonary artery pressure (sPAP) and right-ventricular systolic function did not differ substantially between both groups. Strikingly however, the expression of insulin-like growth factor binding protein 2 (IGFBP-2) was significantly higher in patients, who did not develop RVRR (fold change 1.3 compared to patients with RVRR, p = 0.022). After adjustment for covariates IGFBP-2 was independently associated with absence of RVRR (Odds Ratio 2.078, 95% Confidence interval 1.108 – 3.897, p = 0.023). Conclusions In patients undergoing M-TEER with concomitant moderate or severe TR, numerous cardiometabolic biomarkers including IGFBP-2 are upregulated. Higher levels of IGFBP-2 at baseline are independently associated with persistent TR and/or RV dilation after M-TEER.

CSTB, FABP4, IBP-1 and ST2 are strong predictors of mortality after transcatheter edge-to-edge mitral valve repair

Abstract Introduction Various clinical characteristics have emerged as prognostic factors in patients undergoing transcatheter edge-to-edge mitral valve repair (M-TEER). The use of biomarkers for outcome prediction has enormous potential. The goal of this study was to identify novel biomarkers linked with adverse events after M-TEER. Methods We prospectively included 242 patients undergoing M-TEER at our center and obtained pre-procedural blood samples for biomarker analysis. Additionally, 94 follow-up samples were taken three months after M-TEER. A commercial multiplex protein assay (Cardiovascular III, Olink, Uppsala, Sweden) was used to quantify expression levels of 92 defined biomarkers. We analyzed differences in biomarker expression levels between patients that had died within one year after M-TEER and patients that had survived. Results 39 patients (16.3%) had died within one year after M-TEER. In these patients the most significantly upregulated biomarkers were NT-proBNP (expression 3.0-fold compared to survivors, p &amp;lt; 0.001), Cystatin B (CSTB; 2.0-fold, p &amp;lt; 0.001), fatty acid binding protein 4 (FABP4; 2.0-fold, p &amp;lt; 0.001), insulin-like growth factor-binding protein 1 (IBP-1; 1.9-fold, p &amp;lt; 0.001) and suppression of tumourigenicity 2 (ST2; 1.7-fold, p &amp;lt; 0.001). In non-survivors, expression levels of NT-proBNP (6.1-fold, p = 0.036), CSTB (3.2-fold, p = 0.050), FABP4 (3.7-fold, p = 0.037) and ST2 (2.1-fold, p = 0.017) were persistently elevated at the time of follow-up. Since its prognostic impact has already been described elsewhere, NT-proBNP was excluded from further analysis. Kaplan Meier analysis for 1-year mortality was carried out using tertiles of the respective biomarker expression levels. Mortality risk increased significantly with rising expression levels (CSTB: 3.4% in tertile 1, 12.2% in tertile 2, 37.9% in tertile 3; FABP4: 5.1%, 14.2% and 31.7%; IBP-1: 3.3%, 13.2% and 36.2%; ST2: 4.9%, 11.9% and 36.7%; p by log-rank-test &amp;lt; 0.001 for all biomarkers). Patients in which all 4 biomarkers were elevated to the highest tertile had an excessively high mortality risk of 52.9 vs. 13.5% (p by log-rank-test &amp;lt; 0.001). Receiver operating characteristic (ROC) analysis suggested higher predictive performances for mortality of all 4 biomarkers as compared to the EuroSCORE II (CSTB: area under the curve (AUC) 78.1%, 95% CI 70.7 – 85.5%; FABP4: AUC 71.6%, 95% CI 63.1 – 80.0%; IBP-1: AUC 73.9%, 95% CI 65.7 – 82.1%; ST2: AUC 76.2%, 95% CI 68.5 – 84.0%; EuroSCORE II: AUC 68.4%, 95% CI 59.3 – 77.5%). Conclusion This analysis has revealed novel biomarkers (CSTB, FABP4, IBP-1, ST2), which so far have not been characterized in M-TEER and suggests significant prognostic implications. Predictive performance of each of the respective biomarkers was superior to the most commonly used pre-operative risk stratification tool: the surgical EuroSCORE II. This hypothesis-generating study warrants further examination of these promising biomarkers.

Serum Malondialdehyde-Modified Low-Density Lipoprotein Level May Be a Biomarker Associated with Aortic Stiffness Among Patients Undergoing Peritoneal Dialysis

Background: Serum malondialdehyde-oxidized low-density lipoprotein (MDA-oxLDL) is associated with atherosclerosis and increased risk of cardiovascular disease (CVD). Vascular calcification frequently occurs with arterial stiffness in patients on peritoneal dialysis (PD). This cross-sectional study aimed to elucidate the correlation between aortic stiffness and MDA-oxLDL levels in patients on PD. Methods: Overall, 92 patients on PD were included. The carotid–femoral pulse wave velocity (cfPWV) was evaluated using cuff-based volumetric displacement, and blood samples were obtained from all patients. Aortic stiffness was classified based on cfPWV values (&gt;10 m/s indicating aortic stiffness). Serum MDA-ox-LDL levels were quantified using commercial enzyme-linked immunosorbent assay kits. Results: In total, 33 (35.9%) patients were classified into the aortic stiffness group. Factors, including systolic blood pressure (SBP), serum triglyceride levels, C-reactive protein levels, age, weight, body mass index (BMI), waist circumference, MDA-oxLDL levels, and diabetes mellitus (DM) prevalence, were significantly higher in the aortic stiffness group. Multivariable logistic regression analysis revealed significant associations between aortic stiffness and MDA-oxLDL levels, BMI, and SBP. Furthermore, multivariable forward stepwise linear regression analysis revealed serum MDA-oxLDL levels as a significant independent predictor of cfPWV values. Conclusions: Serum MDA-oxLDL levels correlate positively with cfPWV values and may predict aortic stiffness among PD patients, highlighting its potential role in assessing CVD risk in this population.