Search Results (92)

Background/Objectives: The prevalence of metabolic syndrome (MetS) is steadily increasing worldwide, driven by complex genetic, nutritional, and environmental factors. Caffeine metabolism, primarily mediated by CYP1A2 (though other enzymes such as CYP1A1 may also be involved), and the status of micronutrients such as vitamin B12 and folate have each been linked to MetS components. This study investigates the interaction between CYP1A2 genetic variants and vitamin B12/folate levels in patients with MetS, aiming to identify a novel biomarker axis with potential implications for personalized interventions. Methods: This cross-sectional observational study included 356 adults diagnosed with MetS, recruited from Western Romania. Genotyping for CYP1A2 rs762551 was performed using TaqMan PCR assays. Daily caffeine intake was assessed via validated dietary questionnaires. Serum levels of folate and vitamin B12 were measured using chemiluminescence immunoassays. Results: AA genotype patients with a moderate coffee intake (1–2 cups/day) had significantly higher folate and B12 levels than AC or CC carriers. These nutritional advantages were associated with more favorable BMI and triglyceride profiles. The interaction between CYP1A2 genotype and coffee intake was significant for both micronutrient levels and metabolic parameters, particularly in the AA group. No significant associations were found in high-coffee-intake subgroups (≥3 cups/day). Conclusions: The interplay between CYP1A2 polymorphisms and B-vitamin status may represent a clinically relevant biomarker axis in MetS. Moderate caffeine intake in slow metabolizers (AA genotype) may boost micronutrient status and metabolic health, supporting personalized nutrition. Full article

Background: The early detection of type 1 diabetes (T1D) through screening for major islet autoantibodies is receiving increasing attention as a public health strategy, exemplified by the recent implementation of a pilot pediatric screening program in Italy. The transition from research-based screening to large-scale population initiatives needs automated and standardized assays that are capable of processing extensive sample volumes. Hence, this study aimed to evaluate the analytical performance and comparability of a fully automated chemiluminescence immunoassay (CLIA) compared to a conventional enzyme-linked immunosorbent assay (ELISA) for the detection of three classes of major islet antibodies—anti-GAD (GADA), anti-IA-2 (IA-2A), and anti-ZnT8 (ZnT8A). Methods: A total of 104 serum specimens were analyzed for each autoantibody using both ELISA (RSR and Medyzim, DYNES, DSX) and CLIA (MAGLUMI 800). Assay precision and linearity were assessed through intra-assay variability studies and dilution protocols. Methods agreement was evaluated with Passing–Bablok regression, Spearman’s correlation, Bland–Altman analysis, and Cohen’s kappa statistics. Results: The CLIA showed good precision and excellent linearity across clinically relevant concentration ranges of all islet antibodies. Correlation coefficients and categorical agreement between CLIA and ELISA were high (r > 0.96 and Cohen’s kappa >0.8 for all), with ZnT8A exhibiting the highest concordance. However, proportional biases were found, as CLIA systematically underestimated GADA and ZnT8A levels, while overestimated IA-2A compared to the ELISA. Conclusions: The CLIA displayed satisfactory precision and agreement with ELISA for GADA, IA-2A, and ZnT8A detection. Our findings support the use of these automated immunoassays in large-scale population initiatives for diagnosing T1D, but we also highlight the need for further efforts to achieve better inter-assay harmonization. Full article

The assurance of food safety requires sensitive monitoring of multiple mycotoxins due to their severe impacts on the food industry and high health risks posed to consumers. Herein, we proposed a chemiluminescent/colorimetric dual-signal readout microfluidic method, incorporating a streptavidin-biotin-alkaline phosphatase (SA-Biotin-ALP) signal amplification system for the highly sensitive detection of Deoxynivalenol (DON), Ochratoxin A (OTA), and Aflatoxin B1 (AFB1). The indirect competitive enzyme-linked immunoassay (ic-ELISA) was integrated into microfluidic chip, resulting in sensitive detection ranges of DON in the range of 4–128 ng/mL, 2–64 ng/mL for OTA, and 0.2–6.4 ng/mL for AFB1, with the limit of detection (LOD) being 2.636 ng/mL, 1.492 ng/mL, and 0.131 ng/mL, respectively. Recovery rates in beer samples ranged from 91.93% to 109.31%. Furthermore, a dual-mode microfluidic workstation (DMMW) was developed to facilitate rapid, automated detection for these mycotoxins, simplifying the detection procedure, enhancing the detection efficiency, and reducing the requirement for specialized personnel, thus confirming significant potential for the rapid detection of mycotoxins in complex matrices such as beer. Full article

Background/Objectives: Anti-cyclic citrullinated peptide (anti-CCP) antibodies are highly specific markers for rheumatoid arthritis (RA). Over the past decade, novel automating detection systems have been developed for anti-CCP detection. The present study aimed to evaluate the diagnostic performances of three fully automated anti-CCP assays in comparison to a conventional manual enzyme-linked immunosorbent assay (ELISA). Methods: One hundred ninety-nine patients with rheumatic symptoms (100 with RA and 99 without RA) were tested for anti-CCP autoantibodies using four assays: a manual-ELISA (EUROIMMUN^®), two chemiluminescence immunoassays (CLIAs) performed on the MAGLUMI X3^® and iFlash 1800^® platforms, and an enzyme immunoassay (EIA) run on the UNI^® analyzer. Results: The Kappa statistic indicated a moderate qualitative agreement among the EUROIMMUN, iFlash, and UNI assays (0.734 ≤ ĸ ≤ 0.778), while the MAGLUMI anti-CCP assay showed only weak-to-moderate agreement with the others (0.510 ≤ ĸ ≤ 0.628). A strong positive correlation was observed between anti-CCP levels measured by the four assays (0.747 ≤ rho ≤ 0.839). At the manufacturers’ cut-off values, sensitivities ranged from 76% to 99% and specificities from 69.7% to 99%, depending on the assay. However, at a fixed specificity of 95%, all the four assays showed good diagnostic performances for RA, with sensitivities ranging from 80% to 89% and positive likelihood ratios (LRs+) from 16 to 17.8. Conclusions: Our results revealed that at the manufacturers’ cut-offs, the UNI anti-CCP assay was the most valuable alternative to the conventional ELISA for diagnosing RA in our cohort. Nevertheless, after an appropriate adjustment of the thresholds, all the evaluated assays showed good diagnostic performances for RA. Full article

Neuropsychological interviews and neuroimaging techniques are traditional diagnostic methods for Alzheimer’s disease (AD). However, the development of blood-based biomarkers, such as Amyloid beta (Aβ), phosphorylated Tau (pTau), and their ratios, offers promising non-invasive alternatives for early AD detection. This study aimed to analyze the correlation between CSF and plasma biomarkers (Aβ40, Aβ42, Aβ42/Aβ40, pTau181) and evaluate their diagnostic performance in 51 patients with cognitive impairments. Biomarkers were analyzed in both plasma and CSF using an automated chemiluminescence enzyme immunoassay, Lumipulse (Fujirebio). The results showed significant positive correlations between CSF and plasma levels of Aβ42, the Aβ42/Aβ40 ratio, and pTau181, but not for Aβ40. Plasma Aβ42, pTau181, Aβ42/Aβ40 ratio, and pTau181/Aβ42 ratio demonstrated significant differences between patients A+ vs. A− classified based on CSF Amyloid status, as well as between those classified as A+T+ and A−T− according to both CSF Amyloid and Tau levels. Plasma pTau181, Aβ42/Aβ40, and pTau181/Aβ42 ratio showed high diagnostic accuracy in distinguishing A+ from A− (AUC = 0.93–0.95) and A+T+ from A−T− patients (AUC = 0.93–0.97). These findings suggest that plasma biomarkers can effectively differentiate between AD and other forms of dementia, and serve as a reliable, non-invasive tool for early detection and monitoring of Alzheimer’s disease. Full article

Background: Vitamin D intake and synthesis are essential. Vitamin D deficiency is increasing across all age groups, raising concerns regarding public health. Serum 25(OH)D is measured to define vitamin D deficiency. However, its quantification in non-invasively collected biological matrices is still poorly studied. This study aimed to assess 25(OH)D levels in unconventional matrices using cost-effective analytical methods. Methods: Serum, urine, and saliva were collected from 62 healthy, non-smoking volunteers, 25–44 years of age. Biological samples were analysed using the Enzyme-Linked Immunosorbent Assay (ELISA). The serum was additionally analysed via the chemiluminescent microparticle immunoassay (CMIA), which was used as a benchmark. Results: We observed a linear correlation (Pearson r = 0.44; p = 0.05) between the benchmark and ELISA-measured 25(OH)D urinary levels. After stratification by sex, the correlation was stronger and significant only in females (Pearson r = 0.62; p = 0.04). Salivary 25(OH)D levels did not correlate with serum levels for both ELISA and CMIA measures. Subjects with a CMIA serum-based deficiency showed lower urinary 25(OH)D levels (p = 0.04). Conclusion: Our study opens up the possibility of using urinary 25(OH)D levels as a proxy measurement of vitamin D. Such an approach may allow future investigations on the association between environmental factors and vitamin D assessed in non-invasively collected biological matrices via cost-effective analytical methods. Full article

Biomolecular detection plays essential and irreplaceable roles in safeguarding human health, impeding the transmission of diseases, and augmenting the efficacy of treatments. The precise and specific identification of biomarkers holds profound significance for the early diagnosis, real-time surveillance, and targeted treatment of various diseases. In the initial phases of numerous diseases, the absence of distinct biomarkers in the bloodstream often leads to weak detection signals when using traditional immune detection methods such as enzyme-linked immunosorbent assays (ELISAs), chemiluminescence, and fluorescence chromatography. With the surge in research on surface plasmons, innovative approaches have recently emerged that combine surface plasmon resonance (SPR) with immunological detection techniques, reducing the detection sensitivity to 283 ag/mL, shrinking the sensor size to 2.228 µm², and shortening the detection time to 5.5 min. This review provides an overview of the theoretical foundations of surface plasmon resonance and immunoassays and then delves into the latest advancements in biosensors based on these principles, categorizing them according to their detection mechanisms and methodologies. Finally, we discuss future research directions, opportunities, and the challenges hindering the development of highly sensitive immuno-biochips. Full article

Thyroid function is commonly assessed in dogs through serum measurements of free thyroxine (FT4) and thyroid-stimulating hormone (TSH). The accurate measurement of thyroid hormones is critical. In particular, the measurement of free thyroxine (FT4) is important for the diagnosis and management of thyroid disorders. Most laboratories measure FT4 using direct analog immunoassay methods. The reliability of the results obtained using these methods has often been questioned. Fifty-nine dogs for which the veterinarian had requested the evaluation of thyroid hormones were included in this study. FT4 and TSH were measured using chemiluminescence enzyme immunoassay (CLEIA). Furthermore, FT4 was also measured by liquid chromatography–tandem mass spectrometry (LC-MS/MS) preceded by ultrafiltration. Comparing FT4 with the two different methods, the results demonstrate that LC-MS/MS, preceded by ultrafiltration, provides more accurate and specific FT4 measurements, particularly in dogs with altered thyroid hormone values. Although CLEIA is cost-effective and widely used for screening, LC-MS/MS is recommended for the more precise assessment of thyroid function. Full article

Background/Objectives: Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune-related neurological disease that primarily affects the optic nerve and spinal cord. According to current international consensus guidelines for NMOSD, confirming the presence of aquaporin-4 immunoglobulin G antibody (AQP4-IgG) is one of the most important diagnostic criteria because AQP4-IgG is a significant diagnostic biomarker of NMOSD. Several assays are currently available for detecting AQP4-IgG, including cell-based assays (CBAs) and enzyme-linked immunosorbent assays (ELISAs). However, each assay has certain disadvantages, including insufficient sensitivity and specificity, the need for sophisticated techniques, and semi-quantitative results. Methods: We developed a fully automated chemiluminescent enzyme immunoassay (CLEIA) to detect AQP4-IgG (AQP4-CLEIA). This assay utilizes the recombinant antigen purified from the newly generated AQP4-M23 stably expressing Chinese hamster ovary cell line and an anti-AQP4 monoclonal antibody as a calibrator. Results: In analytical performance studies, the assay demonstrates good precision and linearity over the entire measurement range. Moreover, this assay showed no high-dose hook effect and interference from endogenous substances. In clinical validation studies, patients with AQP4-IgG positive NMOSD, multiple sclerosis, or myelin oligodendrocyte glycoprotein antibody-associated disorder and healthy individuals were tested. A cutoff value of 10.0 U/mL was determined by receiver operating characteristic curves based on the results of a microscopic live CBA. The sensitivity and specificity for AQP4-IgG-positive NMOSD were 97.0% and 100.0%, respectively, at the cutoff value. Conclusions: The results suggest that AQP4-CLEIA is a convenient automated method for measuring AQP4-IgG titers in hospitals and clinical laboratories, offering an effective alternative to the gold-standard CBA. Full article

Porcine circovirus type 2 (PCV2) is the main and primary causative agent of Postweaning Multisystemic Wasting Syndrome (PMWS). To date, immunoperoxidase monolayer assay (IPMA), indirect immunofluorescent assay (IFA), and enzyme linked immunosorbent assay (ELISA) are the most commonly diagnostic methods for detecting PCV2 antigens. However, these methods require specialized equipment and technical expertise and are suitable for laboratory use only. This study aims to develop an immunochromatographic strip and a magnetic chemiluminescence immunoassay for the detection of PCV2 antigens. The recombinant protein was constructed using a prokaryotic expression system, and the polyclonal antibody was obtained by animal experiments. Polystyrene microspheres are used as solid phase carriers to covalently bind to the amino groups of proteins to form immunoprobes. Monodisperse beads are covalently bound to antigens or antibodies as solid phases to bind antibodies or antigens in the liquid phase in a superior manner, thereby capturing and separating antigens and antibodies in the liquid phase. The immunochromatographic strip is qualitative detection method, this method can detect PCV2a strain, PCV2b strain, and PCV2d strain. The immunochromatographic strip had minimum detection limits of 10^2.89TCID₅₀/0.1 mL, 10^3.19TCID₅₀/0.1 mL, and 10^3.49TCID₅₀/0.1 mL for PCV2a/LG, PCV2b/SH, and PCV2d/JH. The results of testing PEDV (CV777 strain), PRV (HB2000 strain), CSFV (WH-09 strain), PRRS (JXA1-R strain), PPV (WH-1 strain), and ASFV (SD strain) were negative. The agreement between the immunochromatographic strip and the ELISA kit was 93.33% (140/150) and the Kappa was 0.866 (Kappa > 0.81). On the premise of ensuring sensitivity, the most important feature of the immunochromatographic strip is that this method can save time when testing; results can be obtained within 5 to 10 min. Magnetic chemiluminescence immunoassay is quantitative detection method; this method can detect PCV2 Cap proteins in swine serum, the linear range of this method was 0.25 ng/mL to 32 ng/mL and R² of the standard curve was 0.9993. The limit of detection (LOD) is 0.051 ng/mL and the limit of quantitation (LOQ) is 0.068 ng/mL. The agreement between the magnetic chemiluminescence immunoassay and the ELISA kit (test PCV2 Cap proteins) was 97.14% (68/70). This method took less than 30 min to achieve results, which is less than the ELISA kit. The results of this study show that immunochromatographic strip and magnetic chemiluminescence immunoassay for PCV2 antigens had great sensitivity and specificity, which lays the foundation for PCV2 clinical detection. Full article

Porcine circovirus 3 (PCV3) is a small non-enveloped circovirus associated with porcine dermatitis and nephropathy syndrome (PDNS). It has occurred worldwide and poses a serious threat to the pig industry. However, there is no commercially available vaccine. PCV3 capsid protein (Cap) is an ideal antigen candidate for serodiagnosis. Here, a novel fully automated chemiluminescence enzyme immunoassay (CLEIA) was developed to detect antibodies (Abs) to Cap in porcine serum. Recombinant PCV3 Cap, self-assembled into virus-like particles (VLPs), was produced using baculovirus and coupled to magnetic particles (Cap-MPs) as carriers. Combined with an alkaline phosphatase (AP)–adamantane (AMPPD) system, Cap-Abs can be rapidly measured on a fully automated chemiluminescence analyzer. Under optimal conditions, a cut-off value of 31,508 was determined, with a diagnostic sensitivity of 96.8% and specificity of 97.3%. No cross-reactivity was observed with PCV1 and PCV2 and other common porcine pathogens, and both intra-assay and inter-assay coefficients were less than 5% and 10%, respectively. Prepared Cap-MPs can be stored at 4 °C for more than 6 months. Importantly, this CLEIA had a good agreement of 95.19% with the commercially available kit, demonstrating excellent analytical sensitivity and significantly reduced operating time and labor. A serological survey was then conducted, and showed that PCV3 continues to spread widely in South China. In conclusion, our CLEIA provides time and labor-saving, and a reliable tool for PCV3 epidemiological surveillance. Full article

Background: Glial fibrillary acidic protein (GFAP) is an important biomarker for neuroinflammatory conditions. Recently, advancements in the treatment of neurological diseases have highlighted the increasing importance of biomarkers, creating a demand for accurate and simple measurement systems for GFAP levels, which are essential for both research and clinical applications. This study presents the development and validation of a novel fully automated immunoassay for the quantitative determination of GFAP levels in biological samples. Methods: We examined the analytical performance of the GFAP assay on the LUMIPULSE platform. The assay’s parameters, including antibody concentrations, incubation times, and detection methods, were optimized to enhance sensitivity and specificity. GFAP levels were measured in 396 serum or plasma samples, comprising both healthy controls and patients with neurodegenerative diseases. Results: In the analytical performance studies, intra- and inter-assay coefficients of variation (CV) were below 5%, indicating high reproducibility. Additionally, the assay demonstrated good linearity over the measurement range. The limit of quantification (LoQ) for this assay was 6.0 pg/mL, which is sufficient for measuring specimens from healthy controls. In clinical validation studies, GFAP levels were significantly elevated in patients with neurodegenerative diseases compared to healthy controls. Conclusions: This automated GFAP assay provides a robust and reliable tool for GFAP measurement, facilitating further research into GFAP’s role in neurological disorders and potentially aiding in the diagnosis and monitoring of these conditions. Full article

Background/Objectives: This study aims to evaluate the possible clinical application of interleukin 8 (IL-8) as a single biomarker and its capabilities in combination with carbohydrate antigen (CA19-9), carcinoembryonic antigen (CEA), and carcinoembryonic antigen cell adhesion molecule 6 (CEACAM6) as diagnostic and prognostic tools for pancreatic ductal adenocarcinoma (PDAC). Methods: A total of 170 serum samples from patients with PDAC (n = 100), chronic pancreatitis (CP) (n = 39), and healthy individuals (n = 31) were analysed. IL-8 and CEACAM6 were measured by an enzyme-linked immunosorbent assay (ELISA). CA19-9 and CEA were determined by chemiluminescent microparticle immunoassay, and bilirubin was quantified using a diazonium salt reaction. Receiver operating characteristic curve analysis, logistic regression, and Kaplan–Meier analyses were performed to evaluate the properties of a single IL-8 and in combination with other biomarkers. Results: The concentrations of IL-8 were statistically significantly higher in the PDAC group compared to the CP and control groups. Heterogeneous levels of IL-8 correlated with PDAC stages (p = 0.007). IL-8 had good and satisfactory diagnostic efficacy in differentiating PDAC from controls (0.858; p < 0.001) and patients with CP (0.696; p < 0.001), respectively. High and low expressions of IL-8 were not significantly associated with overall survival (OS) or disease-free survival (DFS). A combination of IL-8, CEACAM6, and CA19-9 reached the highest AUC values for differentiating PDAC from the control group. The best classification score between PDAC and the control group with CP patients was obtained by merging IL-8 and CA19-9 (0.894; p < 0.001). Conclusions: These results provide compelling evidence of IL-8 as a promising diagnostic biomarker. Nonetheless, due to the high complexity of PDAC, only the conjunction of IL-8, CA19-9, and CEACAM6 integrates sufficient diagnostic capabilities. Full article

This study evaluated the factors influencing IgG/IgM antibody levels in 120 patients with head and neck cancer (HNC) following vaccination with inactivated SARS-CoV-2 vaccines. Each patient’s demographic and clinical data were documented, and serum IgG and IgM antibodies were detected using a commercial magnetic chemiluminescence enzyme immunoassay kit. The results indicated that while all patients had received at least one vaccine dose, 95 tested positive for IgG and 25 were negative. A higher proportion of IgG-positive patients had received three vaccine doses. Comparatively, gamma-glutamyl transferase levels were elevated in IgM-negative patients. The study further differentiated patients based on their treatment status: 46 were treatment-naive and 74 had received chemotherapy combined with immune checkpoint inhibitors (ICT) at enrollment. Despite similar baseline characteristics and time from vaccination to antibody detection, IgM positivity was significantly lower in the ICT group, with no significant difference in IgG positivity between the treatment-naive and ICT groups. A multivariable analysis identified the number of vaccine doses as an independent factor of IgG positivity, while ICT emerged as an independent risk factor for IgM positivity. Additionally, IgG titers generally declined over time, although patients with higher baseline IgG levels maintained higher titers longer. In conclusion, ICT in patients with HNC does not significantly affect IgG levels post-vaccination. However, booster vaccinations have been shown to be associated with higher IgG positivity, although these levels gradually decrease over time. Full article

Background: Therapeutic drug monitoring of biological Tumor Necrosis Factor (TNF)-alpha inhibitors is of critical importance. In this study, the performance of practically advantageous chemiluminescent immunoassays of Theradiag, assessing Infliximab and Adalimumab serum concentrations and anti-drug antibodies (ADA) against these biologics, were compared to the Enzyme-Linked Immuno-Sorbent Assays (ELISAs) from Sanquin Diagnostics. Methods: Leftover serum samples (n = 80 for each parameter) from patients treated with Infliximab or Adalimumab were collected. Correlation and agreement analyses for serum concentration and ADAs, respectively, were performed. Both Theradiag ADA assays, an assay targeting both free and bound ADAs and an assay targeting solely free ADAs, were investigated and compared to the Sanquin Diagnostics ADA assay, targeting both free and bound ADAs. Results: Strong positive correlations were observed between the biologic concentration assessment of Infliximab (Spearman’s Rho = 0.91) and Adalimumab (Spearman’s Rho = 0.94). However, there appeared to be significant bias in the Theradiag assay when compared to Sanquin (Infliximab median (Confidence Interval (CI)) = 2.1 (1.7–2.6) µg/mL; Adalimumab median (CI) = 0.8 (0.5–0.9) µg/mL). Agreement analyses showed moderate to good agreement for the Theradiag and Sanquin Diagnostics ADA assays, when detecting both free and bound ADAs, for Infliximab (Cohen’s k = 0.717) and Adalimumab (Cohen’s k = 0.802). In contrast, the Theradiag ADA assay detecting solely free ADAs had zero to poor agreement for Infliximab (Cohen’s k = 0.458) and Adalimumab (Cohen’s k = 0.119), respectively. Conclusions: This study demonstrated strong correlations and good agreement between the Theradiag and Sanquin Diagnostics assays measuring Infliximab and Adalimumab serum concentrations and ADAs, both free and bound, against these biologics. Discordance analyses showed significantly decreased drug concentrations in the solely free assays, indicating that the combined detection of free and bound ADAs better aligns with drug levels. Full article