Evaluation of chemiluminescence immunoassay kit for detection of hepatitis D virus IgG antibody / 中华检验医学杂志

Objective:This study evaluates the performance of chemiluminescence assay, which is designed to detect Hepatitis D Virus (HDV) Immunoglobulin G (IgG) antibodies.Methods:A comparative analysis was conducted among chemiluminescence anti-HDV IgG reagent, the magnetic particle-based domestic reagent A and domestic reagent B, and the Robo Gene HDV RNA kit, using 1909 HBsAg-positive plasma samples. This comparison aimed to delineate clinical specificity and detection accuracy. The anti-HDV IgG reagent precision was assessed at three different concentration levels following the Clinical Laboratory Standards Institute EP5-A2 guidelines. The specificity of the assay was validated using 200 HAV IgM positive, 545 HBsAg-positive but anti-HDV IgG-negative, 350 anti HCV positive plasma samples and 200 healthy human blood samples. Additionally, a concordance study was conducted with 545 HBsAg-positive and 37 anti-HDV IgG-positive plasma samples, comparing the anti-HDV IgG reagent against reagent A.Results:1 909 HBsAg-positive plasma samples were tested using 3 anti HDV IgG reagent and 1 HDV RNA reagent, 19 samples were identified as anti-HDV IgG-positive. The anti-HDV IgG demonstrated superior accuracy and specificity. The assay exhibited excellent precision, with intra-assay coefficient of variation (CV) values ranging from 1.57% to 4.30%, and inter-assay CV values between 1.71% and 4.67% for detecting samples at high, medium, and low concentration levels. Concordance with Reagent A showed consistent results in both positive and negative detections.Conclusion:In this study, the anti-HDV IgG reagent (chemiluminescence method) displayed outstanding specificity in detecting clinical samples and exhibited a high conformity rate with commercialized reagents, making it potentially suitable for screening anti-HDV IgG in HBsAg-positive samples.

Development and evaluation of a rapid and sensitive POC chemiluminescent assay for β-human chorionic gonadotropin / 中国免疫学杂志

Objective:To develop and evaluate a rapid and sensitive point-of-care chemiluminescent assay(POC-CLIA)for β-human chorionic gonadotropin(β-HCG).Methods:POC-CLIA was constructed based on alkaline phosphatase(Alp)-AMPPD lumi-nescence system and magnetic particles(Mps)carrier.Performance of POC-CLIA,including sensitivity,precision,accuracy,linear dilution,specificity,stability,hook effect and clinical application were evaluated.Results:Detection limit of β-HCG was 0.71 mU/ml,linear detection range was 0.710～1.092×104 mU/ml,and was no hook effect up to 1.7×105 mU/ml.Intra and inter batch coefficients of variation were less than 10％,and could be stored stably at 37℃ for 10 days.Accuracy deviation was within±10％,so results were reliable.There was no cross-reactivity between interfering substances and anti-β-HCG antibdies.For detecting β-HCG in 100 clinical serum samples,results were highly correlated with those that were tested by clinical standard methods(R2=0.997 0).Turnaround time for single sample was less than 15 min and throughput could reach 200 T/h.Conclusion:This method is adequate that can be widely used in grassroots communities to help large-scale screening of pregnancy and related diseases.

Fluorescent probes and imaging techniques for deep-tissue optical imaging:a review / 中国医学物理学杂志

The research advancements in probes for deep-tissue imaging and adaptive optical imaging technologies are summarized,aiming to offer a new perspective for life science and interdisciplinary research.The review firstly gives an introduction on the probes emitting in the near-infrared-Ⅱ region,including fluorescence,bioluminescence,chemiluminescence,and persistent luminescence,and then elaborates direct sensing methods for rapid measurement and correction of wavefront distortions,as well as indirect sensing methods for correcting complex optical aberrations.The continuous updating of the above techniques and methods has enabled optical imaging to successfully penetrate deeper tissues with a remarkable reduction of background noise for higher image quality.

Serum levels of tumor markers and their clinical significance in epithelial ovarian cancer / 中南大学学报(医学版)

Objective: Tumor markers have been widely used clinically. Detection of serum CA125 is one of the commonly used clinical methods for early screening and early diagnosis of epithelial ovarian cancer, but it is difficult to diagnose epithelial ovarian cancer with a single specific tumor marker. In this study, the combinatorial tumor marker detection method was used to compare the value of each tumor marker alone and different combinations in the diagnosis of epithelial ovarian cancer. Methods: The clinical data of patients with epithelial ovarian cancer (n=65) and ovarian benign disease (n=29) were collected. Multiple tumor marker protein chip was used to detect cancer antigen 125 (CA125), carbohydrate antigen 242 (CA242), alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-HCG), carcinoembryonic antigen (CEA), cancer antigen 199 (CA199), neuron-specific enolase (NSE), Ferritin, cancer antigen 153 (CA153), and human growth hormone (HGH) serum levels, and to compare the differences between the benign and malignant ovarian tumors. The correlation between tumor markers and clinicopathologic features for ovarian epithelial carcinoma was analyzed by χ2 test. Spearman rank analysis showed the correlation between CA125 expression level and other tumor markers in epithelial ovarian cancer and the correlation between age and the above 10 tumor markers. Sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and diagnostic efficiency were used to evaluate the diagnostic value of single tumor marker and the combination of tumor markers. Results: The levels of β-HCG, NSE, CA153, and CA125 in the epithelial ovarian cancer group were higher than those in the ovarian benign disease group. The level of NSE in the serum of patients with epithelial ovarian cancer was related to the clinical stage of patients. In addition, the levels of CA242, β -HCG, CEA, NSE, Ferritin, CA153 in the serum of patients with epithelial ovarian cancer were positively correlated with CA125 (rs=0.497, P< 0.001; rs=0.612, P<0.001; rs=0.358, P=0.003; rs=0.680, P<0.001; rs=0.322, P=0.009; rs= 0.609, P<0.001, respectively), and the levels of β-HCG, Ferritin, CA153 were positively correlated with the patient's age (rs=0.256, P=0.040; rs=0.325, P=0.008; rs=0.249, P=0.046, respectively). In the diagnosis of epithelial ovarian cancer, the sensitivity, Youden index, and diagnostic efficiency of CA125 detection alone were higher than the results of the other 9 separate detections. When CA153, CA199, CA242, Ferritin, and CEA were combined with CA125, the sensitivity of the combined detection of different combinations was higher than that of CA125 alone. The combined detection sensitivities of CA125+CEA and CA125+Ferritin+CEA were 89.2％ and 90.8％, respectively, and the diagnostic efficiencies were both 84.1％, which were higher than those of other combinations. The Youden index of CA125+CEA joint detection was 0.616, which was higher than those of other combinations. Conclusion: CA125 has a high diagnostic value in the diagnosis of epithelial ovarian cancer. The detection of combined tumor markers in serum has higher sensitivity and specificity in epithelial ovarian cancer.

HBsAg non-reactive but HBV DNA reactive blood donors in Wuhu area: infection status and tracing results / 中国输血杂志

【Objective】 To detect and analyze the infection status of HBsAg non-reactive /HBV DNA reactive blood donors by individual donor-NAT (ID-NAT) and chemiluminescence technology, and to explore the feasibility and potential risks of reentry. 【Methods】 The blood screening results of blood donors in Wuhu from January 2018 to October 2021 were queried by blood station information management software. The blood donation information of all HBsAg non-reactive /HBV DNA reactive blood donors was collected and then recalled by telephone. After informed consent, samples were taken for HBV DNA nucleic acid single test, enzyme-linked immunoassay for HBsAg, chemiluminescence assay for HBV seromarkers(including HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc), and alanine aminotransferase (ALT) test. All the results were statistically analyzed. 【Results】 From January 2018 to October 2021, there were 142 051 donations, and the positive rate of sole HBV DNA was 0.06% (91/142 051), and 33 people (37 person-times) were successfully followed up. The yield rates of HBsAg, anti-HBs and anti-HBc were 6.06% (2/33), 39.39% (13/33) and 96.97% (32/33), respectively; None HBeAg was yielded. After two times of ID-NAT, 8 patients remained non-reactive to both systems, with a negative conversion rate of 24.24% (8/33). Meanwhile, 25 patients were at least once reactive to ID-NAT, and 23 of them were occult HBV infection with serologically reactivity. There were 2(6.25%) patients with HBsAg positive conversion and HBV DNA persistent reactivity, which were window period infection. One person was confirmed as false reactivity (no HBV infection) as he remained unreactive to both repeated ID-NAT and serological tests. 【Conclusion】 Chemiluminescence assay is more sensitive than ELISA in detecting HBV serum markers, which is beneficial to early detection of HBV samples in window period. The yielding rate of anti-HBc among HBsAg non-reactive/HBV DNA reactive blood donors detected by blood screening in this region is very high, and most of them are occulting infection, so the ID-NAT should be no less than 2 times in the reentry strategy.

Effects of recombinant human interferon α2a suppository on levels of inflammatory factors in cervical mucus of HPV-infected patients / 中国生物制品学杂志

@#Objective To investigate the effects of recombinant human interferon α2a(rhIFNα2a) suppository on the levels of inflammatory factors in the cervical mucus of patients infected with human papillomavirus(HPV).Methods A total of60 HPV-positive patients admitted to the Second Affiliated Hospital of Xi'an Jiaotong University from March to August in 2022 were selected as study objects,and then divided into observation and control groups,30 cases for each group,according to the random number table method.The observation group was given rhIFNα2a suppository therapy by vaginal medication,once every other day,continuous 10 times a month as a course of treatment,and 3 consecutive courses of treatment.The control group did not use drugs.The cervical secretions were collected and the levels of IL-1β,IL-2R,IL-6,IL-8,IL-10 and tumor necrosis factor-α(TNF-α) were measured by chemiluminescence assay.Results After 3 months of treatment,the levels inflammatory factors IL-1β,IL-6,IL-8 and TNF-α in cervical mucus of patients in the observation group were significantly lower than those in the control group(t=-2.717,-2.686,-3.178 and-3.25,respectively,each P <0.05).Compared with before treatment,the levels of IL-1β,IL-6,IL-8 and TNF-α in cervical mucus of patients in the observation group also decreased significantly(t=5.934,4.092,6.495 and 3.287,respectively,each P <0.01),while in the control group,only the level of IL-8 in cervical mucus was significantly different(t=2.345,P=0.024).Conclusion rhIFNα2a suppository can reduce the level of inflammatory factors in cervical mucus,attenuate the inflammatory response and accelerate the clearance of HPV.

Efficacy of non-invasive diagnostic methods in the diagnosis and screening of oral cancer and precancer / Eficácia de métodos diagnósticos não invasivos no diagnóstico e triagem de lesões pré-malignas e malignas na cavidade oral; revisão sistemática e meta-análise

Abstract Introduction: Traditional meta-analyses on the diagnostic accuracy of oral lesions have been conducted, but they were inherently limited to direct pairwise comparisons between a single method and a single alternative, while multiple diagnostic options and the ranking thereof were methodologically not possible. Objective: To evaluate the diagnostic values of various methods in patients with oral potential malignant disease by performing a network meta-analysis. Methods: Two authors independently searched the databases (MEDLINE, SCOPUS, the Cochrane Register of Controlled Trials, and Google scholar) up to June 2020 for studies comparing the diagnostic accuracy of various tools (autofluorescence, chemiluminescence, cytology, narrow band imaging, and toluidine blue) with visual examination or other tools. The outcomes of interest for this analysis were sensitivity, specificity, negative predictive value, positive predictive value and accuracy. Both a standard pairwise meta-analysis and network meta-analysis were conducted. Results: Treatment networks consisting of six interventions were defined for the network metaanalysis. The results of traditional meta-analysis showed that, among six methods, narrow band imaging showed higher sensitivity, specificity, negative predictive value, positive predictive value, and accuracy compared to visual examination. The results of network meta-analysis showed that autofluorescence, chemiluminescence, and narrow band imaging had higher sensitivity compared with visual examination, and that chemiluminescence and narrow band imaging had higher negative predictive value compared with visual examination. However, autofluorescence and chemiluminescence had lower specificity compared with visual examination. There were no significant differences in positive predictive value and accuracy among the six interventions. Conclusion: This study demonstrated that narrow banding imaging has superiority in terms of sensitivity and negative predictive value compared with the other five tested agents.

Resumo Introdução: Metanálises tradicionais sobre a precisão diagnóstica de lesões orais têm sido conduzidas, mas são inerentemente limitadas a comparações pareadas diretas entre um único método e uma única opção, enquanto múltiplas opções de diagnóstico e suas classificações ainda não foram metodologicamente possíveis. Objetivo: Avaliar os valores diagnósticos de vários métodos em pacientes com doença oral potencialmente maligna e fazer uma metanálise de rede. Método: Dois autores pesquisaram independentemente os bancos de dados (Medline, Scopus, Cochrane Register of Controlled Trials e Google Scholar) até junho de 2020 para estudos que comparassem a precisão diagnóstica de várias ferramentas (autofluorescência, quimioluminescência, citologia, imagem de banda estreita e cloreto de tolônio) com exame visual ou outras ferramentas. Os resultados de interesse para esta análise foram sensibilidade, especificidade, valor preditivo negativo, valor preditivo e precisão. Tanto uma metanálise pareada padrão quanto uma metanálise de rede foram conduzidas. Resultados: Redes de tratamento compostas por seis intervenções foram definidas para a metanálise de rede. Os resultados da metanálise tradicional mostraram que, entre seis métodos, a imagem de banda estreita apresentou maior sensibilidade, especificidade, valor preditivo negativo, valor preditivo e precisão em comparação ao exame visual. Os resultados da metanálise de rede mostraram que a autofluorescência, a quimioluminescência e a imagem de banda estreita obtiveram maior sensibilidade em comparação com o exame visual e que a quimioluminescência e a imagem de banda estreita apresentaram maior valor preditivo negativo em comparação com o exame visual. Entretanto, a autofluorescência e a quimioluminescência mostraram especificidade inferior em comparação com o exame visual. Não houve diferenças significativas no valor preditivo e na precisão entre as seis intervenções. Conclusão: Este estudo demonstrou que a imagem de banda estreita demonstra superioridade em termos de sensibilidade e valor preditivo negativo em comparação com os outros cinco agentes testados.

A Case Control Study of Vitamin D Levels in Chronic Obstructive Pulmonary Disease Patients and Healthy Volunteers in South Gujarat, India

Introduction: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) programme states that COPD is a common, treatable, and preventable disease that is characterized by a persistent airflow restriction that usually progresses and is connected to an exaggerated chronic inflammatory response in the airways and the lung to harmful particles or gases. The combined severity of a patient's co-morbid illnesses and exacerbations increases. The purpose of the study was to assess the vitamin D status of COPD patients and healthy participants. Methodology: This case-control study was conducted among 75 cases and 75 control at the Surat Municipal Institute of Medical Education and Research General Medicine department. Result: The mean vitamin D of subjects in cases was 32.21 � 12.68 and it was 52.05 � 1.99 in controls. The difference in vitamin D between the two groups was statistically significant (P Value<0.001). Conclusion: COPD patients had lower amounts of vitamin D. As COPD severity increases, vitamin D levels decrease. Along with a rise in COPD exacerbations, vitamin D levels are also decreasing

Understanding the dynamics of IgM & IgG antibodies in COVID-19-positive patients

Background & objectives: The pandemic caused by the SARS-CoV-2 has been a threat to humankind due to the rapid spread of infection and appearance of multiple new variants. In the present study, we report the dynamics and persistence of immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies in asymptomatic and symptomatic COVID-19 patients by chemiluminescent assay. Methods: A total of 463 serum samples from 218 SARS-CoV-2 PCR-positive patients were collected over a period of 124 days post-onset of disease (POD). Antibody levels were measured by chemiluminescence bioanalyzer. Neutralizing antibody titres were assessed by plaque reduction neutralization test (PRNT) for SARS-CoV-2. Results: Both IgM and IgG started appearing from day five post-infection in symptomatic and asymptomatic patients. IgM antibody response peaked around day 35 POD and rapidly diminished thereafter, with the last IgM-positive sample observed at 90 days POD. IgG antibody response peaked around 45 days POD and persisted till 124 days. The chemiluminescence immunoassay (CLIA) results showed a moderate correlation (R=0.5846, P<0.001) compared with PRNT. Additional analysis indicated a neutralizing titre of 250 corresponded to 12.948 AU/ml of YHLO iFlash SARS-CoV-2 IgG units. Interpretation & conclusions: Both symptomatic and asymptomatic COVID-19 patients seem to initiate production of antibody responses from day five of onset of disease. Although the CLIA gives high sensitivity and specificity and also its binding IgG antibody titres may correlate moderately with protective immunity, our results indicate that the values of binding antibody alone may not be a perfect guide to represent virus neutralization titre during donor selection for plasma therapy. However, IgM and IgG antibody detection may help in monitoring the status of disease progression and burden in the community.

Efficacy of chemiluminescence in the diagnosis and screening of oral cancer and precancer: a systematic review and meta-analysis / Eficácia da quimioluminescência no diagnóstico e rastreamento de câncer oral e pré-câncer: uma revisão sistemática e metanálise

Abstract Introduction Early detection of potentially malignant oral cavity disorders is critical for a good prognosis, and it is unclear whether the use of chemiluminescence as an adjunctive diagnostic screening method improves diagnostic accuracy. Objective This systematic review and meta-analysis was performed to assess the accuracy of chemiluminescence for diagnosis of oral cancer and precancerous lesions. Methods Sixteen prospective and retrospective studies from PubMed, Cochrane database, SCOPUS, Web of Science, Embase, and Google Scholar were reviewed. Oral mucosal disorder, as detected by chemiluminescence, was compared with oral mucosal disorder detected by toluidine blue or visual examination. True-positive, true-negative, false-positive, and false-negative rates were extracted for each study. Methodological quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies tool (ver. 2). Results Sensitivity, specificity, negative predictive value, and diagnostic odds ratio (DOR) of the use of toluidine blue were 0.832 (95% confidence interval [CI] 0.692-0.917), 0.429 (95% CI 0.217-0.672), 0.747 (95% CI 0.607-0.849), and 4.061 (95% CI 1.528-10.796; I2 = 9.128%), respectively. The area under the summary receiver operating characteristic (SROC) curve was 0.743. Compared with toluidine blue, as used in 12 studies, chemiluminescence had a higher sensitivity (0.831 vs. 0.694); it had a lower specificity (0.415 vs. 0.734), negative predictive value (0.674 vs. 0.729), and DOR (3.891 vs. 7.705). Compared with clinical examination, as used in three studies, chemiluminescence had lower DOR (4.576 vs. 5.499) and area under the curve (0.818 vs. 0.91). Conclusion Although chemiluminescence itself has good sensitivity for diagnostic work-up of oral cancer and precancer, the diagnostic accuracy of chemiluminescence is comparable to or worse than toluidine blue and clinical examination. Diagnostic accuracy was therefore insufficient for reliable use of chemiluminescence alone.

Resumo Introdução A detecção precoce de distúrbios orais potencialmente malignos é fundamental para um bom prognóstico e não está claro se o uso da quimioluminescência como método auxiliar de triagem diagnóstica melhora a eficácia do diagnóstico. Objetivo Avaliar a precisão da quimioluminescência para o diagnóstico de câncer oral e pré-câncer. Método Foram revisados 16 estudos prospectivos e retrospectivos dos bancos de dados PubMed, Cochrane, Scopus, Web of Science, Embase e Google Scholar. Os distúrbios da mucosa oral detectados por quimioluminescência foram comparados com os distúrbios da mucosa oral detectados pelo azul de toluidina ou pelo exame visual. Taxas de resultados verdadeiro-positivos, verdadeiro-negativos, falso-positivos e falso-negativos foram extraídas de cada estudo. A qualidade metodológica foi avaliada com a ferramenta Quality Assessment of Diagnostic Accuracy Studies-versão 2 (QUADAS-2). Resultados Sensibilidade, especificidade, valor preditivo negativo e odds ratio diagnóstico do uso do azul de toluidina foram 0,832 (intervalo de confiança de 95%: 0,692-0,917), 0,429 (IC95%: 0,217-0,672), 0,747 (IC95%: 0,607-0,849) e 4,061 (intervalo de confiança 95%: 1,528-10,796; I2 = 9,128%), respectivamente. A área sob a curva SROC, do inglês summary receiver operating characteristic, foi de 0,743. Comparada ao azul de toluidina, como usado em 12 estudos, a quimioluminescência apresentou uma sensibilidade mais alta (0,831 vs. 0,694) e especificidade (0,415 vs. 0,734), valor preditivo negativo (0,674 vs. 0,729) e odds ratio diagnóstico (3,889 vs. 7,705) mais baixos. Comparado com o exame clínico, como usado em três estudos, a quimioluminescência apresentou menor odds ratio diagnóstico (4.576 vs. 5.499) e área sob a curva (0,818 vs. 0,91). Conclusão Embora a quimioluminescência em si tenha boa sensibilidade para o diagnóstico de câncer oral e pré-câncer, sua precisão diagnóstica é comparável ou pior do que o azul de toluidina e o exame clínico. A precisão do diagnóstico foi, portanto, insuficiente para o uso isolado confiável da quimioluminescência.

Study on specific antibodies in patients infected with SARS-CoV-2 and recipients of inactivated vaccine / 中华微生物学和免疫学杂志

Objective:To detect the serum levels of SARS-CoV-2-specific IgM and IgG antibodies in patients infected with SARS-CoV-2 and recipients of inactivated vaccine in different periods for understanding their variation patterns in vivo. Methods:Chemiluminescence immunoassay was used to detect the levels of SARS-CoV-2-specific IgM and IgG antibodies in 144 serum samples of 44 COVID-19 patients, 381 serum samples of 118 asymptomatic infected cases and 398 serum samples of 273 inactivated vaccine recipients collected at different periods. The results were statistically analyzed together with basic characteristics and vaccination status.Results:The positive rates of IgM antibody in COVID-19 patients, asymptomatic infected cases and inactivated vaccine recipients were 52.27% (23/44), 23.73% (28/118) and 14.29% (39/273). The positive rate of IgM antibody was higher in COVID-19 patients than in asymptomatic infected cases and vaccine recipients (χ 2=12.106, P=0.001; χ 2=34.755, P<0.001). The positive rates of IgG antibody in the three populations were 100.00% (44/44), 97.46% (115/118) and 98.81% (166/168), and the differences were not statistically significant (χ 2=2.944, P=0.229). In COVID-19 patients, the concentration of IgM antibody in <40 years old group was lower than that in ≥40 years old group (Waldχ 2=6.609, P=0.010), and the concentration of IgG antibody in patients with vaccination was higher than that in patients without vaccination (Waldχ 2=12.402, P<0.001). In asymptomatic infected cases, the concentration of IgG antibody was higher in people with vaccination than in those without vaccination (Waldχ 2=4.530, P=0.033). In SARS-CoV-2 vaccine recipients, the concentration of IgG antibody in <40 years old group was higher than that in ≥40 years old group (Waldχ 2=9.565, P=0.002). Dynamic analysis of antibody levels showed that from week 1 to week 9, the concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and vaccine recipients. Conclusions:The concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and inactivated vaccine recipients. COVID-19 patients aged ≥40 years had higher level of IgM antibody. COVID-19 patients and asymptomatic infected cases who had received vaccination had higher concentration of IgG antibody. Inactivated vaccine showed good immunogenicity after whole course of immunization, and the IgG antibody level in <40 years old group was higher.

Value of urinary C-terminal agrin fragment in monitoring the progression of early kidney injury in type 2 diabetic patients / 中华检验医学杂志

Objective:This study aimed to explore the feasibility and clinical value of monitoring the progression of early kidney injury in type 2 diabetic patients by assessment of the urinary C-terminal agrin fragment (uCAF) with enzymatic chemiluminescence immunoassay.Methods:A total of 251 patients with type 2 diabetes, who attended the Second Affiliated Hospital of Wenzhou Medical University from October 2018 to March 2020, were included in this retrospective analysis. One hundred and fifty-six participants undergoing health check-up at the Second Affiliated Hospital of Zhejiang University School of Medicine in February 2021 served as controls. Basic clinical information, glycosylated hemoglobin type A 1c and serum creatinine values were recorded, and urine specimens were collected for urinary creatinine, urinary α 1 microglobulin(uα 1M), urinary immunoglobulin G (uIgG), urinary albumin, urinary N-Acetyl-B-D-glycosaminidase (uNAG) and uCAF measurements. Based on the estimated glomerular filtration rate (eGFR), 251 patients were classified into G1~G5 stage groups with 116, 22, 28, 55 and 30 patients in each group. One hundred and sixty-six patients with early diabetic kidney disease (stage G1-G3) were divided into subgroups A1 (79), A2 (48) and A3 (39) according to the urinary albumin/creatinine ratio (UACR), the uα1M levels were divided into uα1M subgroup 1 (83 cases), uα1M subgroup 2 (42 cases), and uα1M subgroup 3 (41 cases), and uIgG subgroup 1 (83 cases), uIgG subgroup 2 (42 cases), and uIgG subgroup 3 (41 cases) according to uIgG levels. The Spearman method was used to analyze the correlation between uCAF levels and eGFR, UACR, uα1M and uIgG levels. Results:(1) The linear range of the uCAF detected by enzymatic chemiluminescence immunoassay was 3.97-2 000.00 ng/ml, with a detection limit of 2.28 ng/ml, intra-batch coefficients of variation of 1.15% and 1.57%, inter-batch coefficients of variation of 1.63% and 5.78%, and a biological reference interval of <95.35 μg/g Cr. (2) The uCAF level and positive rate (UACR≥30 mg/g) increased with the decrease of eGFR from G1-G3, uCAF level was negatively correlated with eGFR value ( r=-0.543, P<0.000 1), and the positive rate increased from 24.14% (28/116) to 85.71% (24/28) from G1-G3. The uCAF level and positivity rate decreased with the decrease of eGFR from G4 to G5. uCAF level was positively correlated with eGFR value ( r=0.495, P<0.001), and the positivity rate decreased from 30.91% (17/55) to 23.33% (7/30) from G4 to G5. (3) In patients with early diabetic kidney disease, uCAF levels and positivity rates increased gradually with the increase of UACR. uCAF levels were positively correlated with UACR values ( r=0.602, P<0.001), and the uCAF positivity rate reached 21.52% (17/79) in the A1 subgroup. (4) uCAF level was positively correlated with uα1M and uIgG levels in patients with early diabetic kidney disease ( r=0.757, 0.596, both P<0.001). Conclusion:Analytical performance of enzyme chemiluminescence immunoassay for the detection of CAF is satisfactory and could be used a biomarker for monitoring damage and progression of early diabetic kidney disease in patients with type 2 diabetes.

Establishment and verification validation of plasma free metanephrines measurement by chemiluminescence immunoassay / 中华检验医学杂志

Objective:To establish a chemiluminescence immunoassay method for free metanephrines measurement in plasma, and verify its performance.Methods:The samples (calibrator, plasma, and quality control sample) were extracted and acylated, the processed analyte samples were then competed with the immobilized specific antigens of metanephrine (MN), normetanephrine (NMN) respectively, to combine specific antibodies marked by Horseradish Peroxidase (HRP), the immobilized antigens-antibody-HRP immune reaction product was then formed through the immune reaction, which could be detected through measurement of HRP catalytic substrate luminescence. Performance verification was performed using specificity, sensitivity,precision,thermally accelerated stability, and accuracy metrics.Results:The established detection methods for MN and NMN have no obvious cross-reactions when detecting multiple structural analogs; the limit of blank, limit of detection and functional sensitivity of the MN detection reagent was 10.51, 21.15 and 25.76 ng/L, and the performance of the NMN detection reagent was 11.54, 28.43 and 31.29 ng/L; the coefficients of variation of the detection reagents for MN and NMN were 2.41%-5.38% and 1.61%-3.22% respectively; the accelerated stability test of the two detection reagents showed that the reagents could be stored stably for 1 year at 2-8 ℃; and the measurement results of this method can be traced to the mass spectrometer.Conclusion:In this study, a chemiluminescence immunoassay detection method for free metanephrines in plasma is successfully established.

Evaluation of CLIA plus NAT for detecting HBsAg single-ELISA-reactive samples of blood donors / 中国输血杂志

【Objective】 To study the detection performance of HBsAg single-ELISA-reactive samples of blood donors. 【Methods】 Two kinds of ELISA reagents from different manufacturers (named as reagents A and B) were used for HBsAg screening. A total of 276 samples, from January 2017 to May 2021, with HBsAg single-ELISA-reactive results were collected for further nucleic acid detection technology (NAT) and chemiluminescence immunoassay (CLIA) testing, to undergo HBV-DNA and five hepatitis B tests, respectively. The relationship between HBsAg single-ELISA-reactivity, NAT and CLIA was statistically analyzed. 【Results】 Among the 276 HBsAg single-ELISA-reactive samples, 14 were NAT reactive, with the positive rate of 5.07% (14/276). Fisher′s exact test was used to compare the compliance of reagents A and B with NAT reactivity, and the difference was not statistically significant (P<0.05). Among 14 HBsAg+ /NAT+ samples retested by CLIA, 2 were HBsAg reactive(14.29%, 2/14), 13 were anti-HBc reactive (92.86%, 13/14), 9 had the quantitative value of anti-HBs <10 mIU/mL, 5 had the quantitative value of anti-HBs between 10 to 100mIU/ mL. A total of 5 serological patterns were detected, and anti-HBe+ /anti-HBc+ pattern was the dominant. There were 262 cases of HBsAg+ /NAT- samples, but only 1 (0.38%, , 1/262) case was HBsAg reactive by CLIA, 100 were anti-HBc reactive (38.17%, 100/262), 144 (54.96%, 144/262) were anti-HBs reactive, and 1 was HBeAg reactive. A total of 8 serological patterns were detected. 【Conclusion】 Most of HBsAg single-ELISA-reactive results are false, and NAT could effectively reduce the residual risk of transfusion transmitted diseases.

Efecto del ácido alfa lipoico sobre la peroxidación no enzimática en mitocondrias de corazón y cerebro de rata / Effect of alpha-lipoic acid against non-enzymatic peroxidation of rat heart and brain mitochondria

RESUMEN El ácido alfa lipoico (AAL) ha sido caracterizado como un antioxidante eficiente. Se ha propuesto como un agente terapéutico potencial en el tratamiento o prevención de diferentes alteraciones que pueden estar relacionadas con un desequilibrio del estado celular oxidoreductor. El objetivo de este trabajo fue analizar la sensibilidad a la peroxidación no enzimática (PNE) (ascorbato-Fe++ dependiente) en mitocondrias de corazón y cerebro de ratas incubadas con una solución de AAL. La PNE fue evaluada por el método de quimioluminiscencia (QL). Cuando se compararon las muestras control (sin el agregado del ascorbato-Fe++) con las muestras ascorbato-Fe++ dependientes, se observó un incremento significativo en la emisión lumínica. Simultáneamente, se incubaron las mitocondrias de ambos órganos con diferentes concentraciones de AAL (0,05, 0,15 y 0,25 mg/ml) observándose una protección diferencial. Las mitocondrias de cerebro de rata incubadas con dosis de 0,15 y 0,25 mg/ml de AAL fueron protegidas de los efectos de la PNE, mientras que, en las mitocondrias cardíacas, solo se observó protección con la dosis más alta de AAL (0,25 mg/ml). El análisis de QL indicó que las mitocondrias de cerebro fueron protegidas de manera más eficiente que las mitocondrias de corazón de rata. En este último caso, será necesario probar nuevas dosis de AAL para demostrar los efectos en estas membranas. En conclusión, AAL actuó como un antioxidante protector de las membranas de ambos órganos contra el daño peroxidativo.

ABSTRACT Alphalipoc acid (ALA) has been characterized as an efficient antioxidant. It has been proposed as a potential therapeutic agent in the treatment or prevention of different pathologies that may be related to an imbalance of the oxido reductive cell state. The objective of this work was to analyze the sensitivity to non-enzymatic peroxidation (NEP) (ascorbate-Fe++ dependent) in heart and brain mitochondria of rats incubated with an ALA solution. NEP was evaluated by the chemiluminescence method (CL). When the control samples (without the addition of ascorbate-Fe++) were compared with the ascorbate-Fe++ dependent samples, a significant increase in the light emission. Simultaneously, the mitochondria of both organs were incubated with different concentrations of ALA (0.05, 0,15 and 0,25 mg/ml), observing a differential protection. Rat brain mitochondria incubated with doses of 0.15 and 0,25 mg/ml of ALA were protected from the effects of NEP, while in cardiac mitochondria, protection was only observed with the highest dose of ALA (0,25 mg/ml). The CL analysis indicated that rat brain mitochondria were protected more efficiently than rat heart mitochondria. In the latter case, it will be necessary to test new doses of ALA to demonstrate the effects on these membranes. In conclusion, ALA acted as a protective antioxidant of the membranes of both organs against peroxidative damage.

Comparison of three methods to detect antibody response to SARS-CoV-2 vaccine / 中华微生物学和免疫学杂志

Objective:To detect IgG and neutralizing antibodies response to SARS-CoV-2 vaccine by comparing enzyme-linked immunosorbent assay (ELISA), commercial magnetic particle chemiluminescence assay(CLIA) and neutralization test(NT).Methods:ELISA, CLIA and NT were used to detect 143 healthy people before and after 28 days immunization with 2 doses of SARS-CoV-2 vaccine, and calculate the positive conversion rate, quantitative results and analysis the consistency of the three methods.Results:The positive conversion rate of SARS-CoV-2 vaccine antibody detected by ELISA, CLIA and NT were respectively 97.9%, 98.6% and 85.3%. The geometric mean of the highest dilution of the serum quantitatively detected by ELISA was 586.6; The mean of CLIA S/CO value was 11.26; The geometric mean titer of the NT was 7.6. The correlation coefficient between ELISA, CLIA and NT were respectively 0.69( P<0.01) and 0.65( P<0.01), and the correlation coefficient between ELISA and CLIA was 0.79( P<0.01). Conclusions:The three methods all detected high levels of antibodies response to SARS-CoV-2 vaccine immunization. ELISA and CLIA are more consistent to detect IgG antibody, and have a good correlation with the quantitative detection results of the NT.

Development and evaluation of a chemiluminescence immunoassay for type Ⅰ procollagen N-terminal peptide / 生物工程学报

To develop a magnetic nanoparticle chemiluminescence immunoassay (CLIA) for the determination of type Ⅰ procollagen N-terminal peptide (PINP) in human serum, we expressed a recombinant PINP-α1 protein in Corynebacterium glutamicum and used it as an immunogen to immunize BALB/c mice. We obtained three hybridoma cell lines that stably secret antibody against PINP-α1 protein. After further pairing and screening, we chose a monoclonal antibody 8C12 coupled with biotin as the capture antibody, and a monoclonal antibody 1F11 labeled horseradish peroxidase as the detection antibody. The antibodies combined with the serum samples, forming a sandwich complex which was used to detect the concentration of PINP in serum. After optimizing the conditions, we determined that the best working concentration of the capture antibody and the detection antibody were 3 μg/mL, and the incubation time was 30 minutes. The quantitative assay had a detection range of 5-1 100 ng/mL, with recovery rates between 93%-107% and the minimum detection limit of 1.22 ng/mL achieved. The intra-and inter-assay precisions were lower than 10%. The correlation coefficient of PINP results between this CLIA method and the Roche electrochemiluminescence immunoassay system was 0.906 2. Therefore, this CLIA method is specific and can be used to quantitatively detect the content of PINP in serum, which has the potential to become an auxiliary approach for bone disease examination.

Molecular characteristics of hepatitis B infection with low level HBsAg and nucleic acid testing non-reactive results in blood donors / 中国输血杂志

【Objective】 To investigate HBV infection with low level of HBsAg and nucleic acid testing(NAT) non-reactive results in blood donors, and analyze molecular characteristics. 【Methods】 Low level HBsAg but NAT-nonreactive samples were collected and tested for HBsAg by Abbott chemiluminescent microparticle immunoassay (CMIA)., HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc were further detected by Roche electrochemiluminescence immunoassay(ECLI). BCP/PC and S regions were also amplified by Nested-PCRs and qPCR for HBV DNA quantity were adopted simultaneously. 【Results】 Of 100 363 donations, 60(0.054%) low level HBsAg and NAT-nonreactive blood samples were enrolled the study. In which, 54/60(90%) and 57/60(95%) were WanTai HBsAg ELISA and DiaSorin HBsAg ELISA reactive respectively. Of 33 cases genotyped, genotype B were 87.9%( 29/33), including adw2 96.6%(28/29) and adw1 3.4%(1/29), C was observed in 4(12.1%) with sero-type adrq+. Mutations in S gene of genotype B such as Q101R, Q129H, T131I, M133L/T, F134L, G145R, V168A, L175S and V177A were observed as notable mutations, which can affect HBsAg diagnosis. A high frequency mutation C1799G(87.5%, 21/24)were detected in BCP/PC and would reduce the replication of virus. The median viral load measured by qPCR was 49.6(0~628)IU/mL. 【Conclusion】 A small part of donations with low-level HBsAg and NAT-nonreactive can not be deferred by one isolated ELISA screening assay. It is necessary to apply more sensitive and specific HBsAg assays and NAT in blood screening, and improve the ability to detected mutants.

Performance analysis of light initiated chemiluminescence assay in detecting anti-HCV, anti-HIV and syphilis / 中国输血杂志

【Objective】 To evaluate the performance of light initiated chemiluminescence assay in the detection of hepatitis c virus (HCV), human immunodeficiency virus (HIV) and Treponema pallidum (TP) antibodies. 【Methods】 According to Guidance on the Verification of Qualitative Measurement Procedures used in the Clinical Immunology(CNAS-GL038: 2019) and Guidance on the Verification of Quantitative Measurement Procedures used in the Clinical Chemistry(CNAS-GL037: 2019), the coincidence rate, detection limit, precision and critical value of the detection of HCV, HIV and TP antibodies by the automatic light initiated chemiluminescence assay system LICA500 were verified. 【Results】 The concordance rate of LICA500 and ELISA in HCV antibody and HIV antibody detection was 100%. In terms of syphilis antibody detection, the concordance rate with TPPA results was 95%. The detection limit test showed that the detection limits of LICA500 against HCV antibody, HIV antibody and TP antibody reached 0.04 NCU/mL, 0.5 NCU/mL and 0.25 NCU/mL, respectively, which were all higher than the manufacturer′s declared detection limits of 0.2 NCU/mL, 1 NCU/mL and 0.5 NCU/mL. The in-batch CV and total CV of LICA500 for HCV, HIV and TP antibodies were less than 10%. The C50 was verified by critical value experiment, and the positive results of HCV antibody, HIV antibody and TP antibody at the critical concentration accounted for 45%, 45% and 48%, respectively. The percentage of negative results for (critical concentration -20%) was 98%, and the percentage of positive results for (critical concentration + 20%) was 100%, indicating that the concentration range from (critical concentration -20%) to (critical concentration + 20%) was in the 95% range of this method. 【Conclusion】 The detection of HCV, HIV and TP antibodies by LICA500 has a high concordance rate with the current commonly used detection methods, suitable for rapid screening and batch examination before surgery and blood transfusion.

Performance evaluation of two chemiluminescence immunoassay reagents for HCV antibody in blood donors screening / 中国输血杂志

【Objective】 Aim of this study was to evaluate performance of two chemiluminescence immunoassay (CLIA) reagents for hepatitis C virus antibodies (anti-HCV) detection, focusing on the feasibility of blood screening for blood donors. 【Methods】 The sero-panel samples from NCCL and the donor samples were tested with CLIA, ECLIA and two ELISA (A: double antigen sandwich method, B: indirect method) reagents synchronously to evaluate their performances respectively, and the sensitivity, specificity and CV of the four reagents were compared. 【Results】 CLIA, ECLIA, A and B reagents showed sensitivities of 99.06%(315/318), 99.69%(317/318), 99.06%(315/318) and 99.69%(317/318), and clinical specificities was 99.06%(315/318), 99.69%(317/318), 99.06%(315/318) and 99.69%(317/318), respectively. Between-run and within-run precision for ECLIA reagent ranged (both CV<8%) was better than two ELISA reagents (between-run: CV <15% and within-run: CV <20%), and the CLIA reagent also met the requirement in blood screening (CVs <14%). 【Conclusion】 This ECLIA reagent showed high sensitivity and good reproducibility together with acceptable specificity in routine sample screening, which proved its further application in blood screening. This CLIA reagent has high specificity and the same sensitivity as indirect ELISA reagent. This CLIA reagent could be used in combination with other reagents with high sensitivity to screen anti-HCV in blood donors.