Chemiluminescent Immunoassay Research Articles

Development of plate-type and tubular chemiluminescence immunoassay against African swine fever virus p72

African swine fever (ASF) is a highly contagious and fatal viral disease that has caused huge economic losses to the pig and related industries worldwide. At present, rapid, accurate, and sensitive laboratory detection technologies are important means of preventing and controlling ASF. However, because attenuated strains of African swine fever virus (ASFV) are constantly emerging, an ASFV antibody could be used more effectively to investigate the virus and control the disease on pig farms. The isolation of ASFV-specific antibodies is also essential for the diagnosis of ASF. Therefore, in this study, we developed two chemiluminescence immunoassays (CLIAs) to detect antibodies directed against ASFV p72: a traditional plate-type blocking CLIA (p72-CLIA) and an automatic tubular competitive CLIA based on magnetic particles (p72-MPCLIA). We compared the diagnostic performance of these two methods to provide a feasible new method for the effective prevention and control of ASF and the purification of ASFV. The cut-off value, diagnostic sensitivity (Dsn), and diagnostic specificity (Dsp) of p72-CLIA were 40%, 100%, and 99.6%, respectively, in known background serum, whereas those of p72-MPCLIA were 36%, 100%, and 99.6%, respectively. Thus, both methods show good Dsn, Dsp, and repeatability. However, when analytical sensitivity was evaluated, p72-MPCLIA was more sensitive than p72-CLIA or a commercial enzyme-linked immunosorbent assay. More importantly, p72-MPCLIA reduced the detection time to 15 min and allowed fully automated detection. In summary, p72-MPCLIA showed superior diagnostic performance and offered a new tool for detecting ASFV infections in the future.Key points• Two chemiluminescence immunoassay (plate-type CLIA and tubular CLIA) methods based on p72 monoclonal antibody (mAb) were developed to detect ASFV antibody.• Both methods show good diagnostic performance (Dsn (100%), Dsp (99.6%), and good repeatability), and p72-MPCLIA detects antibodies against ASFV p72 with high efficiency in just 15 min.

Alzheimer's Disease Related Biomarkers Were Associated with Amnestic Cognitive Impairment in Parkinson's Disease: A Cross-Sectional Cohort Study.

Cognitive impairment is common in patients with Parkinson's disease (PD) and occurs through multiple mechanisms, including Alzheimer's disease (AD) pathology and the involvement of α-synucleinopathies. We aimed to investigate the pathological biomarkers of both PD and AD in plasma and neuronal extracellular vesicles (EVs) and their association with different types of cognitive impairment in PD patients. A total of 122 patients with PD and 30 healthy controls were included in this cross-sectional cohort study between March 2021 and July 2023. Non-dementia PD patients were divided into amnestic and non-amnestic groups according to the memory domain of a neuropsychological assessment. Plasma and neuronal EV biomarkers, including α-synuclein (α-syn), beta-amyloid (Aβ), total tau (T-tau), phosphorylated tau181 (p-tau181), and glial fibrillary acidic protein (GFAP), were measured using a single-molecule array and a chemiluminescence immunoassay, respectively. Neuronal EV but not plasma α-syn levels, were significantly increased in PD as compared to healthy controls, and they were positively associated with UPDRS part III scores and the severity of cognitive impairment. A lower plasma Aβ42 level and higher neuronal EV T-tau level were found in the amnestic PD group compared to the non-amnestic PD group. The results of the current study demonstrate that neuronal EV α-syn levels can be a sensitive biomarker for assisting in the diagnosis and disease severity prediction of PD. Both AD and PD pathologies are important factors in cognitive impairment associated with PD, and AD pathologies are more involved in amnestic memory deficit in PD.

Prevalence of infection and reinfection among health care workers in a hospital of Northern China between BA.5/BF.7 and XBB.1.5 wave

BackgroundTo analyze the epidemiological characteristics of the SARS-CoV-2 infection and reinfection associated with the emergence of Omicron variant in Healthcare workers (HCWs). MethodsWe enrolled 760 HCWs who received 2-4 vaccination doses of COVID-19 and followed by BA.5/BF.7 and/or XBB.1.5 breakthrough infections between December 2022 and July 2023. Serum sample from each individual were collected approximately 1,3 and 6 months after last exposure. IgM, IgG and Total antibodies against SARS-CoV-2 were measured by chemiluminescent immunoassay. Meanwhile, we created an Enterprise WeChat link for HCWs to self-report SARS-CoV-2 infections, symptoms and post COVID-19 conditions. ResultsOur study revealed that the reinfection rate among HCWs reached 26.1%. The main symptoms were fever (91.2% vs 60.1%), cough (78.8% vs 58.0%), and sore throat (75.4% vs 59.6%) during infection and reinfection in Omicron BA.5/BF.7 and XBB.1.5 wave, and the interval for reinfection ranged from 91 to 210 days (median 152). Fatigue (23.6%), memory loss (18.8%) and coughing (18.6%) were the most prevalent long COVID symptoms, with a higher prevalence among female HCWs. ConclusionsHCWs reinfection with SARS-CoV-2 causes milder symptoms, but high reinfection rate and short intervals. Strengthen infection prevention and control is crucial to mitigating infection risk and improving health services.

Anti-Spike IgG antibodies as correlates of protection against SARS-CoV-2 infection in the pre-Omicron and Omicron era.

Anti-Spike IgG antibodies against SARS-CoV-2, which are elicited by vaccination and infection, are correlates of protection against infection with pre-Omicron variants. Whether this association can be generalized to infections with Omicron variants is unclear. We conducted a retrospective cohort study with 8457 blood donors in Tyrol, Austria, analyzing 15,340 anti-Spike IgG antibody measurements from March 2021 to December 2022 assessed by Abbott SARS-CoV-2 IgG II chemiluminescent microparticle immunoassay. Using a Bayesian joint model, we estimated antibody trajectories and adjusted hazard ratios for incident SARS-CoV-2 infection ascertained by self-report or seroconversion of anti-Nucleocapsid antibodies. At the time of their earliest available anti-Spike IgG antibody measurement (median November 23, 2021), participants had a median age of 46.0 years (IQR 32.8-55.2), with 45.3% being female, 41.3% having a prior SARS-CoV-2 infection, and 75.5% having received at least one dose of a COVID-19 vaccine. Among 6159 participants with endpoint data, 3700 incident SARS-CoV-2 infections with predominantly Omicron sublineages were recorded over a median of 8.8 months (IQR 5.7-12.4). The age- and sex-adjusted hazard ratio for SARS-CoV-2 associated with having twice the anti-Spike IgG antibody titer was 0.875 (95% credible interval 0.868-0.881) overall, 0.842 (0.827-0.856) during 2021, and 0.884 (0.877-0.891) during 2022 (all p < 0.001). The associations were similar in females and males (Pinteraction = 0.673) and across age (Pinteraction = 0.590). Higher anti-Spike IgG antibody titers were associated with reduced risk of incident SARS-CoV-2 infection across the entire observation period. While the magnitude of association was slightly weakened in the Omicron era, anti-Spike IgG antibody continues to be a suitable correlate of protection against newer SARS-CoV-2 variants.

Effect of CYP3A5 Gene Polymorphisms on Tacrolimus Blood Concentrations and Adverse Events in Allogeneic Hematopoietic Stem Cell Transplant Patients

BackgroundTacrolimus is the core basic immunosuppressant after transplantation. Cytochrome P450 3A5 (CYP3A5) is the main enzyme involved in tacrolimus metabolism, and rs776746A>G is the most frequently studied polymorphism in the CYP3A5 gene. The aim of this study was to investigate the effect of CYP3A5 gene polymorphisms on tacrolimus blood concentrations and acute graft versus host disease (GVHD) in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT). MethodsThis study included adult patients who received allo-HSCT at the First Affiliated Hospital of Wannan Medical College from January 2021 to June 2022, and received postoperative treatment with tacrolimus. Tacrolimus blood levels were obtained by fully automatic chemiluminescence immunoassay analyzer. Polymerase chain reaction/restriction fragment length polymorphism was used to genotype for CYP3A5*3 allelic variants. ResultsIn a total of 50 transplant patients, 30 patients were detected with CYP3A5*3/*3 genotype, 15 patients with CYP3A5*1/*3 genotype, and 5 patients with CYP3A5*1/*1 genotype. The initial tacrolimus blood concentrations in allo-HSCT patients with CYP3A5*1/*1, *1/*3, and *3/*3 genes were 7.75, 8.61, and 10.19 ng/mL, respectively; The initial blood concentration/dose (C/D) ratios were 4.08, 4.42 and 5.66 ng/(mL·mg), respectively. The C/D ratios of allo-HSCT patients carrying CYP3A5*1/*1, *1/*3, and *3/*3 genes were 4.35 and 4.71 and 5.58, 4.19, 4.56 and 5.71 ng/(mL·mg) in the second and 3rd weeks after operation. These results showed that the blood concentration and C/D ratio of tacrolimus in patients with CYP3A5*3/*3 genotype were significantly higher than those in patients with CYP3A5*1/*3 or CYP3A5*1/*1 genotype. Moreover, the incidence of acute GVHD after allo-HSCT in patients with CYP3A5*1/*1 genotype was significantly higher than that in patients with CYP3A5*1/*3 or CYP3A5*3/*3 genotype. ConclusionsMost patients carry the mutant allele CYP3A5*3. CYP3A5 gene polymorphisms affect tacrolimus blood concentrations and acute GVHD after allo-HSCT.

The annual prevalence of syphilis among blood donors of regional blood centers of Sindh: A study conducted by the Sindh blood transfusion authority to evaluate the infectious rate of syphilis among blood donors.

Objective: To detect any possible illnesses, such as syphilis, and stop them from spreading through transfusion, screening blood donors is crucial. Study Design: Cross-sectional Retrospective Research study. Setting: Four RBCs and the sixteen associated hospital-based blood banks (HBBBs) that are spread over Sindh's various areas. Period: January 2022 to December 2022. Methods: Employing non-probability convenience sampling was carried out. We collected data from Sindh province's Regional Blood Centers (RBCs) and Hospital Based Blood Banks (HBBBs), dispersed throughout the province. Sindh Blood Transfusion Authority (SBTA)'s ethical committee approved the study. To screen selected blood donors for Syphilis, the Chemiluminescence Immunoassay Analyzer (CLIA) was used. Data from the study were summarized using simple percentages after they were statistically examined. Results: With 171,725 male donors and 1,460 female donors, men comprised the bulk of the 173,185 blood donors. Syphilis turned up in 2.5% of the male donors, resulting in an additional 4,311 cases. On the other hand, just 18 (1.2%) of the female donors had a positive syphilis test. The gender distribution of cases with positive Syphilis indicates a notable difference in its frequency between people of both sexes. The age group of 25 to 40 years old accounted for the largest proportion of syphilis cases among blood donors. Conclusion: One of Sindh's biggest public health concerns is the high incidence of syphilis among blood donors. Additionally, the results show that the incidence of syphilis varies by gender. Furthermore, there are considerable age range differences in the distribution of syphilis cases. These results highlight the need for increased screening and preventive programmes, especially in areas with higher incidence rates. Given the high frequency of syphilis among Sindhi red blood cell donors, this could point to a greater number of cases in the overall community.

Serum Vitamin D Level in Inflammatory Bowel Disease (IBD) and it’s Association with IBD Activity Abstract

Vitamin D influences innate immunity, which is believed to be the imbalance of it involved in the pathogenesis of Inflammatory Bowel Disease (IBD). Evidence exists on the association between vitamin D deficiency and inflammatory bowel disease (IBD). To assess the serum vitamin D concentration in patients with inflammatory bowel disease and to study the relationship of vitamin D level with disease activity in the patients with inflammatory bowel disease. This case-control study was carried out in the department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU) on 40 IBD cases, diagnosed on clinical background and 40 apparently healthy control group of similar age and sex. Blood samples were collected and serum vitamin D level was measured with Chemiluminescent Microparticle Immunoassay (CMIA) method in Biochemistry laboratory of BSMMU. The result were analyzed by SPSS version 22. Vitamin D deficiency and insufficiency were defined as serum concentration of ≤20 ng/ml and 21–29 ng/ml respectively. Disease activity were evaluated using the Harvey Bradshaw Index for Crohn’s Disease, Truelove and Witt’s Index for Ulcerative colitis. The vitamin D levels were correlated with disease activity in IBD patients comparing with control group. Mean (±SD) serum vitamin D levels were 16.27 ± 5.16 ng/ml in IBD group and 24.25 ± 6.69 in controls (p &lt;0.001). Almost all (97 %) of IBD patients had low serum vitamin D in comparison to controls; more than three-fourth (77.5%) of the patients of IBD exhibited deficiency (˂20 ng/ml), one-fifth (20%) had insufficiency (21-29 ng/ml) of serum vitamin D, whereas in the controls 30% had deficiency, 42.5% had insufficiency, and 27.5% had sufficient serum vitamin D. There was highly significant inverse correlation between vitamin D level and disease activity in IBD patients. The study showed that IBD patients had significantly lower serum vitamin D levels in comparison to controls. Serum vitamin D concentration is inversely correlated with disease activity in IBD patients. The study suggests that inadequate vitamin D level, along with other factors, probably contributes to the development of active disease in patients with IBD. Bangladesh Med J. 2023 May; 52(2): 20-28

Correlations of erythrocytic oligomer α-synuclein levels with age, sex and clinical variables in patients with Parkinson's disease.

Oligomeric alpha-synuclein in red blood cells (RBC-o-α-Syn) has been shown to be increased in patients with Parkinson's disease (PD). However, factors that affect RBC-o-α-Syn levels remain to be elucidated. The aim of this study is to analyze the correlations between RBC-o-α-Syn levels and the age, sex and different clinical variables of patients with PD. 167 patients with PD and 119 healthy controls (HC) were enrolled in this study. The patients with PD were diagnosed based on the MDS clinical diagnostic criteria for PD. All participants were evaluated for their clinical characteristics. Western blot analysis was used to examine the molecular sizes of RBC-o-α-Syn. A newly established chemiluminescent immunoassay was used to measure RBC-o-α-Syn levels. Higher RBC-o-α-Syn levels were detected in PD patients than in HC subjects. The receiver operating characteristic (ROC) curve indicated that a cut off value of 55.29 ng/mg discriminated well between PD patients and HC subjects, with a sensitivity of 67.66% (95% CI: 60.24-74.29%), a specificity of 88.24% (95% CI: 81.22-92.86%), and an area under the curve (AUC) of 0.857. The levels of RBC-o-α-Syn were higher in female than male patients (p = 0.033). For different subtypes, the levels of RBC-o-α-Syn were higher in the MIX subtype than the tremor-dominant (TD) PD. In addition, the levels of RBC-o-α-Syn were higher in patients with than without cognitive impairment (p = 0.016), and negatively correlated with Mini-Mental State Examination (MMSE) scores (r = -0.156, p = 0.044). Our study demonstrates that RBC-o-α-Syn levels in patients with PD are higher than those in HC subjects and affected by the sex and the severity of cognitive impairment.

Detection of serum CC16 by a rapid and ultrasensitive magnetic chemiluminescence immunoassay for lung disease diagnosis.

It has been reported that serum Clara cell secreted protein 16 (CC16) is a potential biomarker for lung injury diseases, but currently, there is no other method that is faster, more accurate, or more sensitive being applied in clinical practice apart from ELISA. The current study was designed to established a magnetic nanoparticles chemiluminescence immunoassay (MNPs-CLIA) for highly sensitive automated detection of serum Clara cell secretory protein 16 (CC16), and validated its diagnostic performance for lung disease. The study included the expression of CC16 recombinant protein, the preparation and screening of its monoclonal antibody (MAb), as well as the construction, optimization and analytical evaluation of the MNPs-CLIA method. The clinical application value of this method was investigated by detecting CC16 level in 296 serum samples. The linear range of the MNPs-CLIA assay system was 0.2-50 ng/mL, and the limit of detection was 0.037 ng/mL. Performance parameters such as specificity, recovery rate, and precision can meet the industry standards of invitro diagnostic reagents. The established method reveals consistent results with ELISA (R2=0.9962) currently used clinically, and it also exhibits satisfactory diagnostic efficacy of silicosis, chronic obstructive pulmonary disease (COPD), and pulmonary sarcoidosis, with areas under the curve (AUC) of 0.9748, 0.8428 and 0.9128, respectively. Our established MNPs-CLIA method has the advantages of automation, high throughput, rapidity, and simplicity, and can be promoted for widely popularized in clinical applications. MNPs-CLIA detection of serum CC16 has efficient diagnostic potentiality for predicting and diagnosing lung diseases.

Correlation of serum anti-mullerian hormone and age-related health problems with ovarian function

The objectives of this paper were to analyse the correlation between serum Anti-Mullerian Hormone (AMH) and age-related health issues affecting ovarian function and explore the current opportunities for this novel technique. This article mainly focuses on reviewing the biological processes involved in the female reproductive system and the clinical basis of the development of technologies for female fertility. The Serum AntiMullerian Hormone (AMH) test is a valuable tool for the assessment of ovarian function. The AMH level of each individual sample is catalysed using a Roche Elecsys AMH analyzer and a chemiluminescence immunoassay (ECLA), which measures the light emission of the serum complex at 450 nm. The results demonstrated a strong association between serum AMH levels and age, establishing its reliability in the prediction of the ovarian reserve as well as reproductive lifespan. However, age is not the sole determinant for fertility. Genetic factors, oocyte quality, uterine thickness and other environmental factors showed a potential linkage with ovarian syndromes, which indicates poor ovarian function. Market expansion, raising awareness of reproductive health, policy support, and technological advancements provide multiple channels for the promotion of AMH test technology. These findings can be used for business planning or studying age-related changes on the AMH test.

Diagnostic Accuracy of IgA Anti-Transglutaminase Assessed by Chemiluminescence: A Systematic Review and Meta-Analysis.

A new chemiluminescence immunoassay method (CLIA) for detecting IgA anti-transglutaminase (atTG IgA) in celiac disease (CD) has prompted inquiries into its diagnostic performance. We conducted a systematic review and meta-analysis comparing CLIA with traditional enzyme-linked immunosorbent assay (ELISA) and fluorescence enzyme immunoassay (FEIA). We searched PubMed, Medline, and Embase databases up to March 2024. The diagnostic references were intestinal biopsy and ESPGHAN guidelines. We calculated the sensitivity and specificity of atTG IgA assessed by CLIA and the odds ratio (OR) between the assays. Eleven articles were eligible for the systematic review and seven for the meta-analysis. Sensitivity and specificity of atTG IgA CLIA-assay were 0.98 (95% CI, 0.95-0.99) and 0.97 (95% CI, 0.94-0.99), respectively. The sensitivity of atTG IgA antibody detection did not significantly vary across the three assay modalities examined (CLIA vs. ELISA OR: 1.08 (95% CI, 0.56-2.11; p = 0.8); CLIA vs. FEIA OR: 6.97 (95% CI, 0.60-81.03; p = 0.1). The specificity of atTG IgA assessed by FEIA was higher than for CLIA (OR 0.17 (95% CI, 0.05-0.62); p < 0.007). According to the systematic review, normalization of atTG IgA levels in CD patients following a gluten-free diet was delayed when using CLIA compared to ELISA and FEIA methods. Conflicting findings were reported on the antibody threshold to use in order to avoid biopsy confirmation.

Comparison of Four Tests for the Diagnosis of Helicobacter pylori Infection.

Due to lower operational costs, health maintenance organizations (HMOs) may prioritize Helicobacter pylori stool antigen testing (HpStAg) for the non-invasive diagnosis of H. pylori infection over 13C-urea breath tests (13C-UBTs). The aim of our study was to compare the accuracy of the diagnostic tests for H. pylori. We performed histology, rapid urease test (RUT), 13C-UBT and HpStAg on consecutive patients referred for gastroscopy. Monoclonal stool antigen test was performed using the LIAISON Meridian chemiluminescent immunoassay. Histology was examined with hematoxylin and eosin, and additional stains were performed at the pathologist's discretion. For the assessment of 13C-UBT, we compared concordant histology and RUT. HpStAg was compared to the concordant results of two of the three remaining tests. 103 patients were included (36 males (35.0%), age 50.1 ± 18.4 years). The indication for gastroscopy was dyspepsia in 63 (61.2%). Agreement between RUT and histology was 95.9%. For 13C-UBT and HpStAg, respectively, H. pylori positivity was 30% (30/100) and 27.16% (22/81); sensitivity was 97% and 70%; specificity was 100% and 94.4%; accuracy was 98% and 86%; positive predictive value (PPV) was 100% and 86.4%; negative predictive value (NPV) was 93% and 86%. No demographic, clinical, or endoscopic predictors of HpStAg accuracy were identified using logistic regression. 13C-UBT performs better than HpStAg at our institution. When interpreting results, clinicians should consider test limitations.

Establishment of ELISA-comparable moderate and high thresholds for anticardiolipin and anti-β2 glycoprotein I chemiluminescent immunoassays according to the 2023 ACR/EULAR APS classification criteria and evaluation of their diagnostic performance.

Recently published 2023 ACR/EULAR APS classification criteria emphasize the importance of quantifying single-, double-, and triple-antiphospholipid antibody positivity, distinguishing between IgG and IgM isotypes, and delineating moderate/high levels of anticardiolipin (aCL) and anti-β2 glycoprotein I (anti-β2GPI) antibodies. We aimed to establish clinically important moderate/high thresholds for aCL and anti-β2GPI IgG/IgM chemiluminescent immunoassays (CLIA), in particular QUANTA Flash, comparable toour in-house ELISAs used for over two decades, and to evaluate their diagnostic performance. QUANTA Flash CLIA and in-house ELISAs were used to measure aCL and anti-β2GPI IgG/IgM. Moderate thresholds for QUANTA Flash CLIA were determined using a non-parametric approach, calculating a 99th percentile on serum samples from 139 blood donors, and by mirroring the diagnostic performance of in-house ELISA on 159 patient samples. Thresholds for QUANTA Flash CLIA achieving diagnostic performance equivalent to in-house ELISAs were 40 CU for moderate and 80 CU for high levels for aCL and anti-β2GPI IgG and IgM. The assays showed good qualitative agreement, ranging from 76.10 to 91.19 %. When considering in-house ELISA results, 14 out of 80 (17.5 %) patients did not fulfill the new ACR/EULAR laboratory classification criteria, while 27 out of 80 (33.8 %) did not when considering QUANTA Flash CLIA results. We determined moderate and high thresholds for aCL and anti-β2GPI IgG and IgM detected with QUANTA Flash CLIA, aligning with long-established in-house ELISA thresholds. These thresholds are crucial for seamlessly integrating of the new 2023 ACR/EULAR classification criteria into future observational clinical studies and trials.

MiRNAs and indicators of mineral metabolism in the population of dialysis patients

Introduction. Cardiovascular events are the leading cause of death in patients on renal replacement dialysis therapy. The vast majority of patients with CKD 5D have left ventricular hypertrophy (LVH), which is a predisposing factor to diastolic dysfunction, heart failure (HF), arrhythmias, and sudden cardiac death. In recent years, a significant role in the development of cardiovascular pathology in CKD has been attributed to disturbances in calcium and phosphorus homeostasis. Mineral bone correction may have a beneficial effect on LVH.Aim. To evaluate the associations between indices of mineral-bone metabolism and cardiac echocardiography parameters in patients on renal replacement therapy (RRT) with hemo- and peritoneal dialysis, receiving and not receiving phosphate binders.Materials and methods. The study included 75 patients, of whom 53 received treatment with program hemodialysis (HD), 22 with peritoneal dialysis (PD). The control group consisted of 28 healthy volunteers. 43 patients were treated with phosphate binders. Of all patients receiving treatment aimed at correcting hyperphosphatemia, 22 received sevelamer carbonate: 86% of patients took sevelamer carbonate at a dose of 4800 mg/day and 14% at a dose of 2400 mg/day. All biochemical parameters were determined on an automatic biochemical analyzer; FGF-23 was also determined by enzyme-linked immunosorbent assay (ELISA) and the level of intact PTH was determined by chemiluminescence immunoassay. Instrumental studies included echocardiography.Results. In patients with left ventricular hypertrophy (LVMM in the group of patients on hemodialysis 206.6 [120.0; 300.0], in the group on peritoneal dialysis 176.2 [134.0; 204.0]) the level of FGF-23 was significantly increased (p = 0.005). In the group of patients receiving sevelamer carbonate, there was a decrease in the incidence of left ventricular hypertrophy, lower levels of FGF-23 (12.4 ± 5.9), in contrast to the group that did not receive this drug (23 ± 7.3; p = 0.003 ) and PTH (110 ± 27 ng/ml, in the group that did not receive the drug – 340 ± 15; p = 0.01).Conclusions. The use of phosphate binders, in particular sevelamer carbonate, is associated with a decrease in left ventricular hypertrophy and lower levels of FGF-23.

Chemiluminescence immunoassay amplified by functional acridinium ester for the detection of NT-proBNP in clinical samples

High sensitivity and accuracy of heart failure biomarker, N-terminal prohormone brain natriuretic peptide (NT-proBNP), is critical for the early detection of heart failure. However, traditional chemiluminescent (CL) probe still face the challenges of poor solubility, in particular, significant disappointing bioavailability, which profoundly limit its clinical applications. In this paper, we demonstrate functional CL probe acridinium ester (AE-2) for the detection of NT-proBNP, through introducing a hydrophilic unit for ensuring high water dispersity and reactive group for promoting better bioavaiability with antibody. Compared to the traditional CL probe, the functional CL probe AE-2 exhibits extraordinary features, such as better biocompatibility, higher label rate with antibody, as well as significant chemiluminescence signal. In addition, this CL probe exhibits excellent linearity with the test data of Longhua Hospital, suggesting that AE-2 could be used as a clinical examination assay to detect NT-proBNP in real clinical samples. Thus, this functional CL probe AE-2 can be a powerful tool for elucidating the roles of NT-proBNP in clinical samples.

Laboratory evaluation of the Chembio DPP Syphilis Screen &amp; Confirm point-of-care test on serum and simulated blood samples

Introduction: Syphilis infections are increasing in Canada, and traditional serological diagnostics pose barriers for vulnerable and marginalized populations at greatest risk. Point-of-care tests (POCTs) offer solutions, yet none were available in Canada until recently. The Chembio Dual Path Platform (DPP) Syphilis Screen &amp; Confirm (SSC) is one of the first POCTs that helps distinguish active infection from non-infectious syphilis. This study evaluates the reliability of the Chembio DPP SSC to diagnose syphilis infection. Methods: One hundred clinical samples with known syphilis serology (chemiluminescent microparticle immunoassay [CMIA] and rapid plasma regain [RPR]) results were used to evaluate the Chembio DPP SSC. CMIA–ve (n = 20), CMIA+ve RPR–ve (n = 40), and CMIA+ve RPR+ve (n = 40) samples represented negative, past, and presumed active infection, respectively. Samples were used in two formats: serum and simulated blood. Two laboratory technicians read the test visually, and with the manufacturer's DPP Micro Reader, in blinded fashion. Results: Overall sensitivity of the Chembio DPP SSC to distinguish presumed active infection from non-infectious syphilis (past infection and no infection) with visual reads were 52.50% (serum) and 55.00% (simulated blood). Sensitivity increased using the DPP Micro Reader to 90.00% (serum) and 97.50% (simulated blood). Specificity with visual reads were 98.33% (serum) and 95.00% (simulated blood) compared to Micro Reader results of 88.30% (serum) and 80.00% (simulated blood). For the non-treponemal portion of the POCT with visual reads, the sensitivity increased with increasing RPR titers. Low RPR titers &lt;1:4 only had a sensitivity of 42.86% (serum) and 14.29% (simulated blood). Discussion: The laboratory evaluation of the Chembio DPP SSC shows promise in detecting active syphilis, particularly in samples with RPR titers &gt;1:4. However, the need for the Micro Reader for more accurate results is a limitation of the POCT, and financial constraints may pose barriers to some users. Further field evaluation is warranted.

Evaluation and Limitations of the Novel Chemiluminescent Enzyme Immunoassay Technique for Measuring Total Tau Protein in the Cerebrospinal Fluid of Patients with Human Prion Disease: A 10-Year Prospective Study (2011-2020).

Recently, the investigation of cerebrospinal fluid (CSF) biomarkers for diagnosing human prion diseases (HPD) has garnered significant attention. Reproducibility and accuracy are paramount in biomarker research, particularly in the measurement of total tau (T-tau) protein, which is a crucial diagnostic marker. Given the global impact of the coronavirus disease pandemic, the frequency of measuring this protein using one of the world's fully automated assays, chemiluminescent enzyme immunoassay (CLEA), has increased. At present, the diagnosis and monitoring of neurological diseases mainly rely on traditional methods, but their accuracy and responsiveness are limited. There is limited knowledge of the accuracy of CLEA in tau measurements. We aimed to measure T-tau protein using CLEA and to elucidate its merits and limitations. We randomly selected 60 patients with rapidly progressive dementia, using ELISA and CLEA analysis of cerebrospinal fluid specimens. Additionally, we used Western blotting to detect the presence of 14-3-3 protein and employed real-time quaking-induced conversion (RT-QuIC) assays to analyze the same set of samples. Furthermore, we examined the correlation coefficient between ELISA and CLEA results in a subset of 60 samples. Moreover, using CLEA, we evaluated the diurnal reproducibility, storage stability, dilutability, and freeze-thaw effects in three selected samples. In 172 patients, 172 samples were extracted, with each patient providing only one sample, and a total of 88 (35 men and 53 women) tested positive for HPD in the RT-QuIC assay. In contrast, all CSF samples from the remaining 84 patients without HPD (50 men and 34 women) tested negative in the RT-QuIC assay. Both ELISA and CLEA showed perfect sensitivity and specificity (100%) in measuring T-tau protein levels. In addition, ELISA and CLEA are similar in terms of measurement sensitivity and marginal effect of detection extrema. CLEA analysis exhibited instability for certain samples with T-tau protein levels exceeding 2000 pg/mL, leading to low reproducibility during dilution analysis. Our findings indicate that CLEA outperforms ELISA in terms of diurnal reproducibility, storage stability, and freeze-thaw effects. However, ELISA demonstrated superior performance in the dilution assay. Therefore, it is imperative to develop innovative approaches for the dilution of biomarker samples for CLEA measurements during clinical trials.

Advancing Microfluidic Immunity Testing Systems: New Trends for Microbial Pathogen Detection.

Pathogenic microorganisms play a crucial role in the global disease burden due to their ability to cause various diseases and spread through multiple transmission routes. Immunity tests identify antigens related to these pathogens, thereby confirming past infections and monitoring the host's immune response. Traditional pathogen detection methods, including enzyme-linked immunosorbent assays (ELISAs) and chemiluminescent immunoassays (CLIAs), are often labor-intensive, slow, and reliant on sophisticated equipment and skilled personnel, which can be limiting in resource-poor settings. In contrast, the development of microfluidic technologies presents a promising alternative, offering automation, miniaturization, and cost efficiency. These advanced methods are poised to replace traditional assays by streamlining processes and enabling rapid, high-throughput immunity testing for pathogens. This review highlights the latest advancements in microfluidic systems designed for rapid and high-throughput immunity testing, incorporating immunosensors, single molecule arrays (Simoas), a lateral flow assay (LFA), and smartphone integration. It focuses on key pathogenic microorganisms such as SARS-CoV-2, influenza, and the ZIKA virus (ZIKV). Additionally, the review discusses the challenges, commercialization prospects, and future directions to advance microfluidic systems for infectious disease detection.

Urinary-based detection of MSL, HE4 and CA125 as an additional dimension for predictive and prognostic modelling in ovarian cancer.

We have recently described a predictive/prognostic model for ovarian cancer, exploiting commonly available clinico-pathological parameters and the ovarian serum biomarkers mesothelin (MSL), human epididymis protein 4 (HE4) and cancer-antigen 125 (CA125). Considering urine as a prototype non-invasive sample, we investigated whether serum levels of these biomarkers are mirrored in urine and compared their clinical relevance in matched serum vs. urine samples. MSL, HE4 and CA125 were quantified in urinary (n=172) and matched serum samples (n=188) from ovarian cancer patients (n=192) using the Lumipulse® G chemiluminescent enzyme immunoassay (Fujirebio). While absolute concentrations of MSL or CA125 were higher in serum than in matched urine samples, HE4 concentrations were considerably higher in urine than in serum. Nonetheless, the levels of all three biomarkers strongly correlated between matched serum vs. urine samples and were unrelated to BRCA1/2 mutational status. Consequently, prediction of surgical outcome or relapse/death by MSL, HE4 or CA125 was similarly efficient among urinary- vs. serum-based detection. HE4 provided the highest capacity to predict surgical outcome or relapse/death among both body fluids (urine: AUC=0.854; serum: AUC=0.750, respectively). All clinically relevant findings regarding the investigated urinary biomarkers were equally reproducible among raw vs. creatinine-normalized datasets, suggesting that normalization may have subordinate priority for urine-based analysis of these biomarkers. We report that the capacity of MSL, HE4 and CA125 to predict surgical outcome and relapse/death is equivalent between serum vs. urine-based detection. Urinary biomarkers, in particular HE4, may provide an additional dimension for prognostic modeling in ovarian cancer.

Association of Robust Anti-SARS-CoV-2 Trajectories among Communities with and without COVID-19 Infection

Globally, 767 million people have been affected by SARS-CoV-2 infection and nearly a population of 6.94 million were deceased as per the World Health Organization (WHO) as of June 7, 2023. In India, the spreading of infections is now being restricted by the use of BBV-152 (CovaxinTM) and ChAdOx1-nCOV (CovishieldTM) vaccines. The present study comprises 327 candidates and Chemiluminescent microparticle immunoassay (CMIA) was used as a quantitative analytical tool to detect IgG and IgM antibodies. Out of 327 candidates, 177 (54.1%) were vaccinated and 150 (45.9%) were non-vaccinated. Among vaccinated and non-vaccinated candidates, 49 (27.7%%) and 44 (29.3%) had a history of infection, respectively; meanwhile, most of the study participants were immunized with CovishieldTM (n=145, 81.9%) and 18.1% (n=32) were immunized with CovaxinTM. There were insignificant differences observed among immunized as well as non-immunized study participants in considering median age, gender, age categories, IgM levels, or IgM seropositivity. Predictably, there was an important variation in IgG median values and IgG positivity noticed among the immunized and non-immunized categories as well as between populations with and without preceding infections. Our research is hence coherent with prospective requirements for booster shots to assist in controlling the rate of infections and fatality rates together throughout the pandemic conditions.