To develop a national reference panel for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)antigen detection kit and establish a quality standard.The cultures of SARS-CoV-2 and other pathogens were collected...To develop a national reference panel for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)antigen detection kit and establish a quality standard.The cultures of SARS-CoV-2 and other pathogens were collected to establish a national reference panel for SARS-CoV-2 antigen detection.The stability and homogeneity of the reference panel were evaluated.Based on World Health Organization(WHO)guidance and nucleic acid quantitative results,a quality standard reference panel was established.Currently,three generations of SARS-CoV-2 antigen national reference materials with batch numbers 370095–202001,370095–202202,and 370095–202203 have been successfully established.These national reference panels comprised 8 positive samples,20 negative samples,1 repetitive sample,and 1 lower detection limit sample.The stability and homogeneity of the reference panel meet the requirements.The quality standards are as follows:the positive and negative coincidence rates are 8/8 and 20/20,respectively.The 10 test results of the medium and low-concentration repetitive reference materials should be positive,and the color rendering should be uniform(or the coefficient of variance should not be higher than 20.0%).The lower detection limit should be at least 5×105 U/mL(equivalent to copies/mL),and higher concentrations above the lower detection limit must be positive.A national reference panel for the SARS-CoV-2 antigen detection kit has been established.As the standard of SARS-CoV-2 antigen reagents,the reference panel has played a crucial role in the pre-marketing quality evaluation and post-marketing quality supervision in China.展开更多
At present,with the development of technology,the detection of cryptococcal antigen(CRAG)plays an increasingly important role in the diagnosis of cryptococcosis.However,the three major CRAG detection technologies,late...At present,with the development of technology,the detection of cryptococcal antigen(CRAG)plays an increasingly important role in the diagnosis of cryptococcosis.However,the three major CRAG detection technologies,latex agglutination test(LA),lateral flow assay(LFA)and Enzyme-linked Immunosorbent Assay,have certain limitations.Although these techniques do not often lead to false-positive results,once this result occurs in a particular group of patients(such as human immunodeficiency virus patients),it might lead to severe consequences.展开更多
Many factors have been identified as having the ability to affect the sensitivity of rapid antigen detection(RAD)tests for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).This study aimed to identify the i...Many factors have been identified as having the ability to affect the sensitivity of rapid antigen detection(RAD)tests for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).This study aimed to identify the impact of sample processing on the sensitivity of the RAD tests.We explored the effect of different inactivation methods,viral transport media(VTM)solutions,and sample preservation on the sensitivity of four RAD kits based on two SARS-CoV-2 strains.Compared with non-inactivation,heat inactivation significantly impacted the sensitivity of most RAD kits;however,β-propiolactone inactivation only had a minor effect.Some of the VTM solutions(VTM2,MANTACC)had a significant influence on the sensitivity of the RAD kits,especially for low viral-loads samples.The detection value of RAD kits was slightly decreased,while most of them were still in the detection range with the extension of preservation time and the increase of freeze–thaw cycles.Our results showed that selecting the appropriate inactivation methods and VTM solutions is necessary during reagent development,performance evaluation,and clinical application。展开更多
Antigen detection provides particularly valuable information for medical diagnoses;however,the current detection methods are less sensitive and accurate than nucleic acid analysis.The combination of CRISPR/Cas12a and ...Antigen detection provides particularly valuable information for medical diagnoses;however,the current detection methods are less sensitive and accurate than nucleic acid analysis.The combination of CRISPR/Cas12a and aptamers provides a new detection paradigm,but sensitive sensing and stable amplification in antigen detection remain challenging.Here,we present a PCR-free multiple trigger dsDNA tandem-based signal amplification strategy and a de novo designed dual aptamer synergistic sensing strategy.Integration of these two strategies endowed the CRISPR/Cas12a and aptamer-based method with ultra-sensitive,fast,and stable antigen detection.In a demonstration of this method,the limit of detection was at the single virus level(0.17 fM,approximately two copies/μL)in SARS-CoV-2 antigen nucleocapsid protein analysis of saliva or serum samples.The entire procedure required only 20 min.Given our system’s simplicity and modular setup,we believe that it could be adapted reasonably easily for general applications in CRISPR/Cas12a-aptamer-based detection.展开更多
Middle East respiratory syndrome coronavirus(MERS-CoV)infection in humans has a high mortality of>30%.Dromedaries are the reservoir of MERS-CoV and the main source of human infections.However,MERS-CoV infections in...Middle East respiratory syndrome coronavirus(MERS-CoV)infection in humans has a high mortality of>30%.Dromedaries are the reservoir of MERS-CoV and the main source of human infections.However,MERS-CoV infections in dromedaries are usually subclinical.Rapid diagnosis of MERS-CoV infection in these animals is important in preventing camel-to-human transmission of the virus.The possible cross-reactivity of a previously reported rapid nucleocapsid protein-based antigen detection assay for MERS-CoV was examined with different CoVs,including Tylonycteris bat CoV HKU4,dromedary camel CoV UAE-HKU23,human CoV-229E,human CoV-OC43,severe acute respiratory syndrome CoV-2 and rabbit CoV HKU14,where none of them showed false-positive results.The assay was further validated using quantitative real-time reverse transcription-polymerase chain reaction-confirmed MERS-CoV-positive and MERS-CoV-negative dromedary nasal samples collected in Dubai,the United Arab Emirates,which showed that the rapid antigen detection assay has a specificity of 100%and sensitivity of 91.7%.展开更多
Objective To explore a highly sensitive and highly specific method to detect the serum MG7 antigen(Ag)level for early gastric cancer diagnosis.Methods The serum MG7-Ag level was detected by enzyme-linked immunosorbent...Objective To explore a highly sensitive and highly specific method to detect the serum MG7 antigen(Ag)level for early gastric cancer diagnosis.Methods The serum MG7-Ag level was detected by enzyme-linked immunosorbent assay(ELISA)method in 116 preoperative gastric cancer patients,63 postoperative gastric cancer patients,41 patients with precancerous lesion,37 pa-展开更多
During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochem...During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochemistry[1].The dengue virus non-structural antigen NSl that would develop before the appearance of dengue IgM and/or IgG is emerging as a suitable option for dengue diagnosis[2].Platelet therapy is a standard clinical practice for dengue patients with severe thrombocytopenia[3].However,during introductory screening,platelet count is not being done in many cases. This results in delays of platelet therapy. In the course of the current(2010) spurt of dengue in New Delhi[4],simultaneous screening for NSl,IgM and IgG and platelet enumeration has been introduced at the展开更多
Background Screening for opisthorchiasis,a parasitic worm infection affecting many millions of people in Southeast Asia,has traditionally relied on faecal egg examination such as the formalin-ethyl acetate concentrati...Background Screening for opisthorchiasis,a parasitic worm infection affecting many millions of people in Southeast Asia,has traditionally relied on faecal egg examination such as the formalin-ethyl acetate concentration technique(FECT)and Kato-Katz method.Although the urinary enzyme-linked immunosorbent assay(ELISA)has been used more recently,we developed a urinary antigen-based rapid diagnostic test(RDT)to simplify diagnosis and as a point-of-care testing(POCT)and field applications for surveillance and control of opisthorchiasis.Methods A urinaryOpisthorchis viverrini(OV)-RDT was developed using immunochromatographic methodology with a specific monoclonal antibody against OV.The diagnostic performance of the urinary OV-RDT was compared to that of quantitative faecal FECT and urinary antigen ELISA(n=493).Cross-reactivities of urinary OV-RDT with other helminthiases coexisted withO.viverrini were determined(n=96).A field trial in the application of urinary OV-RDT was compared with urinary antigen ELISA at baseline screening and assessment of drug treatment outcomes in opisthorchiasis(n=1629).The McNemar chi-square,Kruskal-Wallis and Cohen’s kappa coefficient(κ-value)tests were used for statistical analyses.Results Urinary OV-RDT had sensitivity of 94.2%and specificity of 93.2%,compared to faecal FECT.Urinary OV-RDT had high diagnostic agreement(Kappa=0.842-0.874,P<0.001)and quantitative correlation with urinary antigen ELISA(Kruskal-Wallis tests=316.2,P<0.0001)and faecal FECT(Kruskal-Wallis tests=362.3,P<0.0001).The positive rates by OV-RDT,ELISA and FECT were 48.9%,52.5%and 49.3%,respectively.Cross-reactions of urinary OV-RDT with other helminthiases were few(2%).Field trials of urinary OV-RDT yielded comparable prevalence ofO.viverrini between urinary OV-RDT(53.2%)and urinary antigen ELISA(54.0%).OV screening showed high diagnostic agreement(kappa>0.8,P<0.0001)between urinary OV-RDT and urinary antigen ELISA.The cure rates of opisthorchiasis at 1 month post-praziquantel treatment determined by urinary OV-RDT(86.6%)and urinary antigen ELISA(80.5%)were similar(P>0.05).Conclusions The urinary OV-RDT test has high potential as a new tool for screening and evaluating treatment outcomes in opisthorchiasis.The ease of sample collection and simplicity of urinary OV-RDT may facilitate mass screening,control and elimination of opisthorchiasis,thereby contributing to a reduction in the disease burden in Southeast Asia.展开更多
Early detection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection is an efficient way to prevent the spread of coronavirus disease 2019(COVID-19).Detecting SARS-CoV-2 antigen can be rapid and con...Early detection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection is an efficient way to prevent the spread of coronavirus disease 2019(COVID-19).Detecting SARS-CoV-2 antigen can be rapid and convenient,but it is still challenging to develop highly sensitive methods for effective diagnosis.Herein,a lateral flow assay(LFA)based on fluorescent nanoparticles emitting in the second near-infrared(NIR-II)window is developed for sensitive detection of SARS-CoV-2 antigen.Benefiting from the NIR-II fluorescence with high penetration and low autofluorescence,such NIR-II based LFA allows enhanced signal-to-background ratio,and the limit of detection is down to 0.01 ng·mL^(−1)of SARS-CoV-2 antigen.In the clinical swab sample tests,the NIR-II LFA outperforms the colloidal gold LFA with higher overall percent agreement with the polymerase chain reaction test.The clinical samples with low antigen concentrations(~0.015–~0.068 ng·mL^(−1))can be successfully detected by the NIR-II LFA,but fail for the colloidal gold LFA.The NIR-II LFA can provide a promising platform for highly sensitive,rapid,and cost-effective method for early diagnosis and mass screening of SARS-CoV-2 infection.展开更多
基金supported by the National Key Research and Development Program of China (2021YFC2400904)the National Science and Technology Major Project of China (2018ZX10102001).
文摘To develop a national reference panel for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)antigen detection kit and establish a quality standard.The cultures of SARS-CoV-2 and other pathogens were collected to establish a national reference panel for SARS-CoV-2 antigen detection.The stability and homogeneity of the reference panel were evaluated.Based on World Health Organization(WHO)guidance and nucleic acid quantitative results,a quality standard reference panel was established.Currently,three generations of SARS-CoV-2 antigen national reference materials with batch numbers 370095–202001,370095–202202,and 370095–202203 have been successfully established.These national reference panels comprised 8 positive samples,20 negative samples,1 repetitive sample,and 1 lower detection limit sample.The stability and homogeneity of the reference panel meet the requirements.The quality standards are as follows:the positive and negative coincidence rates are 8/8 and 20/20,respectively.The 10 test results of the medium and low-concentration repetitive reference materials should be positive,and the color rendering should be uniform(or the coefficient of variance should not be higher than 20.0%).The lower detection limit should be at least 5×105 U/mL(equivalent to copies/mL),and higher concentrations above the lower detection limit must be positive.A national reference panel for the SARS-CoV-2 antigen detection kit has been established.As the standard of SARS-CoV-2 antigen reagents,the reference panel has played a crucial role in the pre-marketing quality evaluation and post-marketing quality supervision in China.
基金Supported by the Key Discipline of Jiaxing Respiratory Medicine Construction Project,No.2019-zc-04.
文摘At present,with the development of technology,the detection of cryptococcal antigen(CRAG)plays an increasingly important role in the diagnosis of cryptococcosis.However,the three major CRAG detection technologies,latex agglutination test(LA),lateral flow assay(LFA)and Enzyme-linked Immunosorbent Assay,have certain limitations.Although these techniques do not often lead to false-positive results,once this result occurs in a particular group of patients(such as human immunodeficiency virus patients),it might lead to severe consequences.
基金supported by China's National Science and Technology Major Project(2018ZX10102001)the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2019PT3100292020PT310004).
文摘Many factors have been identified as having the ability to affect the sensitivity of rapid antigen detection(RAD)tests for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).This study aimed to identify the impact of sample processing on the sensitivity of the RAD tests.We explored the effect of different inactivation methods,viral transport media(VTM)solutions,and sample preservation on the sensitivity of four RAD kits based on two SARS-CoV-2 strains.Compared with non-inactivation,heat inactivation significantly impacted the sensitivity of most RAD kits;however,β-propiolactone inactivation only had a minor effect.Some of the VTM solutions(VTM2,MANTACC)had a significant influence on the sensitivity of the RAD kits,especially for low viral-loads samples.The detection value of RAD kits was slightly decreased,while most of them were still in the detection range with the extension of preservation time and the increase of freeze–thaw cycles.Our results showed that selecting the appropriate inactivation methods and VTM solutions is necessary during reagent development,performance evaluation,and clinical application。
基金This work was supported by the National Key R&D program of China(2020YFA0907800)the National Natural Science Foundation of China(31922002,31720103901,31772242 and 31870040),the 111 Project(B18022)+1 种基金the Fundamental Research Funds for the Central Universities[22221818014]the Youth Innovation Promotion Association CAS(Y202027)to W.W and the Open Project Funding of the State Key Laboratory of Bioreactor Engineering.
文摘Antigen detection provides particularly valuable information for medical diagnoses;however,the current detection methods are less sensitive and accurate than nucleic acid analysis.The combination of CRISPR/Cas12a and aptamers provides a new detection paradigm,but sensitive sensing and stable amplification in antigen detection remain challenging.Here,we present a PCR-free multiple trigger dsDNA tandem-based signal amplification strategy and a de novo designed dual aptamer synergistic sensing strategy.Integration of these two strategies endowed the CRISPR/Cas12a and aptamer-based method with ultra-sensitive,fast,and stable antigen detection.In a demonstration of this method,the limit of detection was at the single virus level(0.17 fM,approximately two copies/μL)in SARS-CoV-2 antigen nucleocapsid protein analysis of saliva or serum samples.The entire procedure required only 20 min.Given our system’s simplicity and modular setup,we believe that it could be adapted reasonably easily for general applications in CRISPR/Cas12a-aptamer-based detection.
基金supported by the Health and Medical Research Fund-Commissioned Research on Control of Infectious Diseases(Phase IV,CID-HKU6)a donation of TE Health Consultant Company Limitedthe framework of the Higher Education Sprout Project by the Ministry of Education(MOE-111-S-023-A)in Taiwan.
文摘Middle East respiratory syndrome coronavirus(MERS-CoV)infection in humans has a high mortality of>30%.Dromedaries are the reservoir of MERS-CoV and the main source of human infections.However,MERS-CoV infections in dromedaries are usually subclinical.Rapid diagnosis of MERS-CoV infection in these animals is important in preventing camel-to-human transmission of the virus.The possible cross-reactivity of a previously reported rapid nucleocapsid protein-based antigen detection assay for MERS-CoV was examined with different CoVs,including Tylonycteris bat CoV HKU4,dromedary camel CoV UAE-HKU23,human CoV-229E,human CoV-OC43,severe acute respiratory syndrome CoV-2 and rabbit CoV HKU14,where none of them showed false-positive results.The assay was further validated using quantitative real-time reverse transcription-polymerase chain reaction-confirmed MERS-CoV-positive and MERS-CoV-negative dromedary nasal samples collected in Dubai,the United Arab Emirates,which showed that the rapid antigen detection assay has a specificity of 100%and sensitivity of 91.7%.
文摘Objective To explore a highly sensitive and highly specific method to detect the serum MG7 antigen(Ag)level for early gastric cancer diagnosis.Methods The serum MG7-Ag level was detected by enzyme-linked immunosorbent assay(ELISA)method in 116 preoperative gastric cancer patients,63 postoperative gastric cancer patients,41 patients with precancerous lesion,37 pa-
文摘During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochemistry[1].The dengue virus non-structural antigen NSl that would develop before the appearance of dengue IgM and/or IgG is emerging as a suitable option for dengue diagnosis[2].Platelet therapy is a standard clinical practice for dengue patients with severe thrombocytopenia[3].However,during introductory screening,platelet count is not being done in many cases. This results in delays of platelet therapy. In the course of the current(2010) spurt of dengue in New Delhi[4],simultaneous screening for NSl,IgM and IgG and platelet enumeration has been introduced at the
基金supported by the Cholangiocarcinoma Research Institute,Khon Kaen University,Thailand.This project is funded by the National Science Research Council of Thailand(NRCT)the Post-Doctoral Training Program from Khon Kaen University,Thailand(PD2565-02-01)supported by the Thailand Centre of Excellence for Life Sciences(TCELS)SDT-R was funded by the Wellcome Trust ISSF grant at Imperial College London.
文摘Background Screening for opisthorchiasis,a parasitic worm infection affecting many millions of people in Southeast Asia,has traditionally relied on faecal egg examination such as the formalin-ethyl acetate concentration technique(FECT)and Kato-Katz method.Although the urinary enzyme-linked immunosorbent assay(ELISA)has been used more recently,we developed a urinary antigen-based rapid diagnostic test(RDT)to simplify diagnosis and as a point-of-care testing(POCT)and field applications for surveillance and control of opisthorchiasis.Methods A urinaryOpisthorchis viverrini(OV)-RDT was developed using immunochromatographic methodology with a specific monoclonal antibody against OV.The diagnostic performance of the urinary OV-RDT was compared to that of quantitative faecal FECT and urinary antigen ELISA(n=493).Cross-reactivities of urinary OV-RDT with other helminthiases coexisted withO.viverrini were determined(n=96).A field trial in the application of urinary OV-RDT was compared with urinary antigen ELISA at baseline screening and assessment of drug treatment outcomes in opisthorchiasis(n=1629).The McNemar chi-square,Kruskal-Wallis and Cohen’s kappa coefficient(κ-value)tests were used for statistical analyses.Results Urinary OV-RDT had sensitivity of 94.2%and specificity of 93.2%,compared to faecal FECT.Urinary OV-RDT had high diagnostic agreement(Kappa=0.842-0.874,P<0.001)and quantitative correlation with urinary antigen ELISA(Kruskal-Wallis tests=316.2,P<0.0001)and faecal FECT(Kruskal-Wallis tests=362.3,P<0.0001).The positive rates by OV-RDT,ELISA and FECT were 48.9%,52.5%and 49.3%,respectively.Cross-reactions of urinary OV-RDT with other helminthiases were few(2%).Field trials of urinary OV-RDT yielded comparable prevalence ofO.viverrini between urinary OV-RDT(53.2%)and urinary antigen ELISA(54.0%).OV screening showed high diagnostic agreement(kappa>0.8,P<0.0001)between urinary OV-RDT and urinary antigen ELISA.The cure rates of opisthorchiasis at 1 month post-praziquantel treatment determined by urinary OV-RDT(86.6%)and urinary antigen ELISA(80.5%)were similar(P>0.05).Conclusions The urinary OV-RDT test has high potential as a new tool for screening and evaluating treatment outcomes in opisthorchiasis.The ease of sample collection and simplicity of urinary OV-RDT may facilitate mass screening,control and elimination of opisthorchiasis,thereby contributing to a reduction in the disease burden in Southeast Asia.
基金Guangdong Provincial Department of Science and Technology-key research and development project(No.2020B1111160003)Shenzhen Science and Technology Innovation Commission technology breakthrough project(No.JSGG20191231141403880)+1 种基金Shenzhen San-Ming Project(No.SZSM201809085)Shenzhen Science and Technology Innovation Commission general project(No.JCYJ20180504165657443)。
文摘Early detection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection is an efficient way to prevent the spread of coronavirus disease 2019(COVID-19).Detecting SARS-CoV-2 antigen can be rapid and convenient,but it is still challenging to develop highly sensitive methods for effective diagnosis.Herein,a lateral flow assay(LFA)based on fluorescent nanoparticles emitting in the second near-infrared(NIR-II)window is developed for sensitive detection of SARS-CoV-2 antigen.Benefiting from the NIR-II fluorescence with high penetration and low autofluorescence,such NIR-II based LFA allows enhanced signal-to-background ratio,and the limit of detection is down to 0.01 ng·mL^(−1)of SARS-CoV-2 antigen.In the clinical swab sample tests,the NIR-II LFA outperforms the colloidal gold LFA with higher overall percent agreement with the polymerase chain reaction test.The clinical samples with low antigen concentrations(~0.015–~0.068 ng·mL^(−1))can be successfully detected by the NIR-II LFA,but fail for the colloidal gold LFA.The NIR-II LFA can provide a promising platform for highly sensitive,rapid,and cost-effective method for early diagnosis and mass screening of SARS-CoV-2 infection.
