The research advances of clinical characteristics and experimental detection of emerging tick-borne viral diseases in China / 中华检验医学杂志

As the second largest vector of infectious diseases, ticks carry and transmit various pathogens that cause human infections and pose a serious public health hazard. In recent years, there has been an ongoing epidemic of tick-borne fever with thrombocytopenia syndrome virus (SFTSV), as well as the occurrence of human infections by brand-new viruses such as Jingmen tick virus (JMTV) and Alongshan virus (ALSV) in China. This paper will review the advancement of disease clinical characteristics, laboratory methods of virus isolation, immunology and molecular biology of these emerging tick-borne viral diseases in China.

Emphasis of rapid and accurate laboratory diagnosis of insect-borne infectious diseases / 中华检验医学杂志

In recent years, with the change of natural and social factors, such as climate warming, urbanization, land reclamation, human population growth, change of life customs, and convenient transportation, the human infectious diseases transmitted by insect vectors, well known as insect-borne infectious diseases, has increased significantly, causing a serious threat to public health. This paper focuses on the epidemiology, clinical characteristics, especially laboratory diagnosis of insect-borne infectious diseases, and emphasizes that medical institutions should pay attention to the rapid and accurate laboratory diagnosis of insect-borne infectious diseases. Metagenomic next generation sequencing has potential value in the diagnosis of insect-borne infectious diseases with unknown causes.

Expression characteristic of autoantibodies and association with outcome in COVID-19 patients / 中华检验医学杂志

Objective:To investigate the difference and characteristics of autoantibodies expression in patients infected by 2019-nCoV with various severity, and explore the associations between expression profile of autoantibodies and prognosis of COVID-19 patients.Methods:This retrospective study was conducted on patients with COVID-19 admitted to Zhongnan Hospital, Wuhan University from January 30, 2020 to March 16, 2020. Data on medical records, expression of autoantibodies including antinuclear antibody profile (ANA), anticardiolipin antibody (ACA), inflammatory factor and other laboratory indexes were collected and analyzed. The age and sex matched disease controls (cases of pulmonary infection unrelated to 2019-nCoV infection and autoimmune disease) and healthy controls (healthy check-up individuals) were also included. Following groups were established, ANA test groups: 72 cases of COVID-19 group (including 17 critical and severe cases, and 55 mild cases), 37 disease controls and 44 healthy controls; ACA test groups: 111 cases of COVID-19 group (including 37 critical and severe cases, and 74 mild cases), 37 disease controls and 40 healthy controls. The difference of positive rate or expression level of autoantibodies among various groups was analyzed, and the difference of inflammatory biomarkers and other parameters were compared between patients with ANA positive results and negative results. The Spearman correlation test was applied to determine the relationship between ACA and other parameters. Kaplan-Meier estimation was used to plot survival curves, the log-rank analysis was utilized to explore the association between antibodies and outcome of COVID-19 patients.Results:The positive rate of antibodies was significantly higher in the COVID-19 group than disease and healthy control groups, the ANA fluorescence: 22.22% (16/72), 5.41% (2/37), 6.82% (3/44); ANA spectrum:26.39% (19/72), 8.11% (3/37), 9.09% (4/44); and ACA:37.84% (42/111), 8.11% (3/37), 5.00% (2/40); all P<0.05. The positive rate of ANA, ACA-IgM and the expression level of ACA-IgM were significantly higher in severe COVID-19 subgroups (critically and severe COVID-19 patients) than in the mild COVID-19 patients (the ANA fluorescence: 47.06% [8/17] vs. 14.55% [8/55], ANA spectrum:66.67% [9/17] vs. 18.18% [10/55], ACA-IgM:30.43% [10/37] vs. 9.46% [7/74]; all P<0.05). There were significant differences in the number of red blood cells, hemoglobin concentration, hematocrit, activated partial thromboplastin time, C-reactive protein, interleukin-6 and serum amyloid A between COVID-19 ANA-positive group and COVID-19 ANA-negative group (all P<0.05). The level of ACA-IgM was positively correlated with white blood cell count ( r=0.354, P<0.001), neutrophil count ( r=0.344, P<0.001), platelet count ( r=0.198, P=0.038), D-Dimer ( r=0.260, P=0.009), glutamic-pyruvic transaminase ( r=0.214, P=0.024), γ-glutamyl transpeptidase ( r=0.283, P=0.003), blood urea nitrogen ( r=0.223, P=0.019), and negatively correlated with superoxide dismutase ( r=-0.228, P=0.020). Survival analysis showed that cumulative survival rate of event-free survival (EFS) was lower in patients with positive ANA/ACA-IgM results than in patients with negative ANA/ACA-IgM results ( P<0.05). Conclusions:ANA and ACA autoantibodies can be detected in COVID-19 patients. The positive rate and the expression level of ANA and ACA increase in proportion with the severity of COVID-19 patients. ANA and ACA-IgM could be used as risk stratification determinants for predicting survival of COVID-19 patients.

The application of nano-biosensors in the detection of 2019-nCoV / 中华检验医学杂志

The pandemic of 2019 novel coronavirus (2019-nCoV) infection since 2020 caused Coronavirus Disease 2019 (COVID-19) leads the serious threaten to global public health. It is urgent to diagnose COVID-19, guide epidemiological measures, control the infection rates, research/develop the antiviral treatment and promote the vaccine research. The application of nano-material based biosensors (the nano-biosensors) has achieved the high-performance detection of a variety of biomarkers due to their small device size, label free detection, high sensitivity, good specificity, short detection time, and has been considered as great potential to become a point-of-care testing tool for detecting 2019-nCoV. Therefore, by summarizing the working principle and classification of nano-biosensors, and focusing on the research progress of nano-biosensors in the detection of 2019-nCoV reported in the recent years, our review provides the challenges and future development prospects of the nano-biosensor in clinical laboratory.

Value precision quantification of autoantibody assay / 中华检验医学杂志

Autoantibodies play an important role in aiding to the diagnosis, as well as judging diseases activity and monitoring treatment of autoimmune disorders. The combined detection of multiple autoantibodies is the current mainstream detection method. However, results are frequently reported as qualitative or semi-quantitative. The newly released diagnostic/classification standards for autoimmune diseases require quantitative detection data about the level of autoantibodies. The higher the level of autoantibodies is, the more likely the patient is to be diagnosed as an autoimmune disease, and it may be more relevant to the activity of the autoimmune disease. This article makes an introduction about the clinical value of accurate quantitative detection of autoantibodies as well as the current statues and challenges at the moment.

Potential value of extracellular vesicles/exosomes in diagnosis and treatment of COVID-19 / 中华检验医学杂志

Since the outbreak of the novel coronavirus pneumonia (COVID-19), it is urgently to develop the effective strategies for its clinical test or treatments world widely. Extracellular vesicles (EV)/exosomes could function as effective carriers for intercellular communication. Increasing evidence revealed that mesenchymal stem cell-derived EV/exosomes could be considered as an alternative cell-free therapy against the acute respiratory distress syndrome. Moreover, the EV-related metabolomics, proteomics, relapsing, deep-vein-thrombosis, myocardial-toxicity, liquid-biopsy and bio-therapeutic researches focusing on the COVID-19 will not only extended our knowledge for the diagnosis, but also provide novel ideas for treatment of this fatal disease. This article will systemically review the progresses of EV/exosomes in the diagnosis and treatment of COVID-19.

Analysis of false-negative results for 2019 novel coronavirus nucleic acid test and related countermeasures / 中华检验医学杂志

In December 2019, a cluster of patients with pneumonia of unknown cause were linked to a seafood wholesale market in Wuhan, China. Some studies found that the virus was a new kind of virus which had never been found in the human body. Then, the virus was named 2019 Novel Coronavirus (2019-nCoV) by the World Health Organization (WHO). 2019-nCoV nucleic acid detection is one of the essential indicators of NCP (Novel Coronavirus Pneumonia). Recently, some false-negative cases in China-Japan Friendship Hospital and Hangzhou Hospital led the clinical doctors to question the value of the nucleic acid detection. In this paper, more than 3 000 results of 2019-nCoV detection in Zhongnan Hospital, Wuhan University were analyzed. Attention should be paid to the root cause of false-negative results and the related countermeasures should be taken.

Value of chest CT screening in the early COVID-19 outbreak / 中华放射学杂志

Objective@#In view of the difficulty of the shortage of new coronavirus nucleal acid test in the early COVID-19 outbreak, to explore the application value of chest CT in screening COVID-19 patients.@*Methods@#Retrospective analysis was performed on the data of patients with fever who received chest CT and new coronavirus nucleal acid test during January 25, 2020 to February 2, 2020 in Zhongnan Hospital of Wuhan University. A total of 587 patients were enrolled, including 290 males and 297 females, aged from 11.0 to 96.0 (51.3±17.1) years old. Take the nucleic acid test results as the gold standard, the sensitivity, specificity and rate of missed diagnosis of CT screening COVID-19 were calculated.@*Results@#Among the 587 patients, there were 433 positive cases (73.8%, 433/587) and 154 negative cases (26.2%, 154/587) of novel coronavirus nucleic acid test. Using CT screening, 494 cases (84.2%, 494/587) were positive and 93 cases (15.8%, 93/587) were negative. The sensitivity of CT screening COVID-19 was 97.7% (423/433), specificity was 53.9% (83/154) and rate of missed diagnosis was 2.3% (10/433).@*Conclusions@#In the early COVID-19 outbreak, CT screening has the advantages of high sensitivity and low rate of missed diagnosis of COVID-19, which can compensate for the shortage of new coronavirus nucleal acid test and can be used as the basis for rapid screening for early prevention and control of COVID-19 outbreak.

The methodological comparison of Pandoraea sputorum identification / 中华检验医学杂志

Objective:The matria-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS) and sequencing methods were performed to assess the methodology (biochemistry methods) for identifying the Pandoraea sputorum and provide the more preferred approach to identify Pandoraea species. Methods:This paper is a study on performance evaluation of identification method. Ten lines of Pandoraea sputorum were isolated from blood cultures of inpatients were collected at Zhongnan Hospital of Wuhan University from July to October 2018 and were confirmed by the cultural characteristics, colonial morphology and Gram′s stain. Further identification was carried out by using the manual biochemical method (API 20NE), automatic biochemistry systems(BioMerieuxVITEK 2 Compact, BD Phoenix-100andThemo ARIS 2X), MALDI-TOF MS (BioMerieuxVITEK MS and Bruker MALDI Biotyper) and the sequencing methods of the 16S rRNA to identify the Pandoraea sputorum. Results:Pandoraea sputorum was non-fermented gram-negative bacteria that are non-motile, oxidase positive, and catalase positive. Ten lines of Pandoraea sputorum were identified as Achromobacter denitrificans, Alcaligenes faecalis or Cupriavidus pauculus and the accuracy rate of genus and species identification was 0 by API 20NE. Among all the samples, six lines were identified as the Pandoraea spp. with the accuracy rate of genus identification was 6/10 by VITEK 2 Compact; whereas the other four lines were identified as the Burkholderia cepacia, Sphingomonas paucimobilis, Ralstonia pickettii, or "Low Discrim" . All of these were identified as "No Identification" by Phoenix-100, which the accuracy rate of genus and species identification was 0. Seven isolates were identified by ARIS 2X as Stenotrophomonas maltophilia, Acinetobacter lwoffii, Sphingomonas paucimobilis, Pseudomonas luteola, Acinetobacter baumannii/Acinetobacter haemolyticus; whereas the other three lines were identified as rare species, thus, the accuracy rate of genus and species identification was 0. Both VITEK MS and MALDI Biotyper indicated all the isolates were Pandoraea sputorum with the accuracy rate of genus and species identification was 10/10. 16S rRNA sequencing for the 10 isolates showed they have 100% of similarity to Pandoraea sputorum by blasting with Genebank. Conclusions:Methods based on biochemical reactions often failed to accurately identify the Pandoraea sputorum to species level. MALDL-TOF MS and 16S rRNA sequencing technology identify Pandoraea sputorum efficiently and precisely enough.

Principle and application of isothermal amplification technology / 中华检验医学杂志

Isothermal amplification technology is a new class of nucleic acid amplification technology that performs amplification under constant temperature conditions. With the advantages of simple operation, high sensitivity and specificity, this kind of technology shows a good application prospect in clinical detection and scientific research. The principle, characteristics and applications of loop-mediated isothermal amplification(LAMP), crossing priming amplification (CPA),strand displacement amplification(SDA), recombinase polymerase amplification (RPA), nucleic acid sequence-based amplification (NASBA), rolling circle amplification (RCA) and helicase-dependent amplification (HDA) are reviewed in this paper.

Causes and countermeasures of false-negative results for 2019 novel coronavirus nucleic acid test / 中华检验医学杂志

In December 2019, a cluster of patients with pneumonia of unknown cause were linked to a seafood wholesale market in Wuhan, China. Some studies found that the virus was a new kind of virus which had never been found in the human body. Then, the virus was named 2019 novel coronavirus (2019-nCoV) by the World Health Organization (WHO). 2019-nCoV nucleic acid detection is one of the essential indicators of COVID-19. Recently, some false-negative cases in China-Japan Friendship Hospital and Hangzhou Hospital led the clinical doctors to question the value of the nucleic acid detection. In this paper, more than 3 000 results of 2019-nCoV detection in Zhongnan Hospital, Wuhan University were analyzed. Attention should be paid to the root cause of false-negative results and the related countermeasures should be taken.

Value of chest CT screening in the early COVID-19 outbreak / 中华放射学杂志

Objective:In view of the shortage of new coronavirus nucleal acid test in the early COVID-19 outbreak, the application value of chest CT in screening COVID-19 patients was explored.Methods:Retrospective analysis was performed on the data of patients with fever who received chest CT and new coronavirus nucleal acid test during January 25, 2020 to February 2, 2020 in Zhongnan Hospital of Wuhan University. A total of 587 patients were enrolled, including 290 males and 297 females, aged from 11.0 to 96.0 (51.3±17.1) years old. Taking the nucleic acid test results as the gold standard, the sensitivity, specificity and rate of misdiagnosis of CT screening were calculated.Results:Among the 587 patients, there were 433 positive cases (73.8%, 433/587) and 154 negative cases (26.2%, 154/587) of novel coronavirus nucleic acid test. Using CT screening, 494 cases (84.2%, 494/587) were positive and 93 cases (15.8%, 93/587) were negative. The sensitivity of CT screening was 97.7% (423/433), specificity was 53.9% (83/154) and rate of misdiagnosis was 2.3% (10/433).Conclusions:In the early COVID-19 outbreak, CT screening has the advantages of high sensitivity and low rate of misdiagnosis, which can compensate for the shortage of new coronavirus nucleal acid test and can be used as a rapid screening for early prevention and control.

Advantages and suggestions for medical MOOC education in the information age / 中华医学教育探索杂志

Massive open online courses (MOOC) is an emerging teaching mode based on website, which has been developed rapidly in China since 2013. Contemporary medical education, assisted by MOOC, diverges greatly with various modes. In this paper, the current situation and advantages of MOOC on medical education in the information age were analyzed, and suggestions for improvement of MOOC on modern medical education were proposed in combination with foreign case study, which is conducive to the reform and innovation of medical education model.

Comparison of clinical efficacy of gefitinib and erlotinib treating non-small-cell lung cancer with epider-mal growth factor receptor mutation in either exon 19 or 21 / 国际肿瘤学杂志

Objective To compare the clinical outcomes of gefitinib and erlotinib treating non-small-cell lung cancer (NSCLC)with epidermal growth factor receptor (EGFR)mutation in either exon 19 or 21 . Methods A total of 242 patients diagnosed as NSCLC with EGFR mutation in either exon 19 or 21 from May 201 3 to December 2014 in our hospital were chosen in this study.According to age,sex,smoking history,eastern cooperative oncology group performance status and types of EGFR mutation,all the patients were matched to 121 pairs,and randomly divided into group A and B.Patients in group A received gefitinib treatment,and those in group B received erlotinib treatment.Based on the response evaluation criteria in solid tumors (RECIST),overall response rate (ORR),disease control rate (DCR),progression-free survival (PFS)were assessed.To assess the independent risk factors for PFS by univariate and multivariate Cox regression analysis.The subgroup analysis was performed for the 63 NSCLC patients using these two drugs as the first-line treatment.To evaluate the adverse drug reactions and quality of life between A and B groups.Results The median PFS of group A and B were 11 .6 months and 9.5 months,respectively,with no significant difference (HR =0.39,P >0.05).The ORR and DCR in the two groups were 76.9%,74.4% (χ2 =1 .03,P =0.58)and 90.1 %,86.8% (χ2 =1 .46,P =0.31 ). The independent risk factors of poor PFS were ECOG PS≥2 (HR =2.60,95%CI:1 .54 -4.43,P =0.001 )and non-adenocarcinoma (HR =3.61 ,95%CI:1 .54-8.66,P =0.003).For patients receiving these two drugs as the first-line treatment,there was no significant difference between two groups in overall response rates (76.6% vs. 90.2%,χ2 =0.83,P =0.12)and median PFS (11 .6 months vs.14.4 months,HR =0.59,P >0.05).The adverse drug reactions were significant differences in emotion function (F =10.27,P =0.03),diarrhea (F =10.24,P =0.03)and pain (F =9.02,P =0.04).After receiving drug treatment,the quality of life scores were improved,and most of the differences were statistically significant between A and B groups(P <0.05). Conclusion As for NSCLC with EGFR mutation in either exon 1 9 or 21 ,both gefitinib and erlotinib are well tolerated and have similar clinical effectiveness.

Determination of longistylin A and longistylin C in Cajanus cajan / 中国中药杂志

<p><b>OBJECTIVE</b>To establish quality control criteria for medicinal herb Cajanus cajan based on the determination of longistylin A and longistylin C, two bioactive and specific stilbenes of the plant.</p><p><b>METHOD</b>Longistylin A and longistylin C were obtained from the leaves of C. cajan by silica gel column chromatography and identified as marker compounds of this plant by spectroscopic analysis. A RP-HPLC method was established to determine the two compounds.</p><p><b>RESULT</b>Longistylin A and longistylin C were well separated on a Thermo BDS Hypersil C18 column (4.6 mm x 250 mm, 5 microm) with a mobile phase methanol-water (8:2), and showed good linearity in the range of 0.00288 - 0.0576 microg and 0.0112 - 0.224 microg, respectively. The average recoveries were 98.9% and 97.2% with RSD of 2.4% and 2.2% for these two compounds, respectively.</p><p><b>CONCLUSION</b>The established analysis method is simple and accurate, whicn can be used for quality control of C. cajan.</p>

Study on the correlation between a set of single nucleotide polymorphisms of hepatitis B virus core gene and serum HBV DNA levels in patients with chronic hepatitis B / 中华微生物学和免疫学杂志

Objective To investigate the relation between a set of single nucleotide polymorphisms (SNP) in core gene of HBV in chronic hepatitis B patients and HBV DNA levels. Methods PCR restriction fragment length polymorphism(PCR-RFLP) assay and restriction enzyme Tsp509I were adopted to determine HBV SNP in HBV core gene. Nucleotide sequences of core gene were determined using the dideoxy chain termination method. HBV DNA levels were quantitated with real-time PCR. Results Five typical RFLP patterns, RFLP-C, RFLP-D, RFLP-E, RFLP-G and RFLP-C/G mixture were found and the distribution of HBV RFLP patterns was as follows: C, 61. 5% ; D, 2. 6% ; E, 9.6%; G, 16.7%; C/G mixture, 9.6%. Five SNPs, A165T, A336C, A336T, T337C and T385C, were found to be associated with RFLP patterns change and only SNP A336C or A336T caused the substitution of Glu-83 with Asp in HBcAg. The serum HBV DNA levels in RFLP-C group were higher than that in RFLP-G (P =0. 02) and RFLP-C/G group(P = 0. 006) , respectively, furthermore, the positive rate of serum ALT in RFLP-C/G group was lower than that in RFLP-C, RFLP-E and RFLP-G group, respectively. Under the condition of HBeAg-positive, the serum HBV DNA levels in RFLP-C group were higher than that in RFLP-G (P = 0. 015) and RFLP-C/G group(P =0.008) , respectively. Conclusion PCR-RFLP used in this study can be adopted to determine HBV SNPs, not genotypes in Chinese patients with chronic hepatitis B. The serum HBV DNA level in RFLP-C group higher than that in RFLP-G or RFLP-C/G group maybe associated with amino acid mutation, Glu83 Asp.

Upregulation of phagocytic clearance of apoptotic cells by autoimmune regulator / 华中科技大学学报（医学）（英德文版）

To investigate the effect of autoimmune regulator (AIRE) on phagocytic clearance of apoptotic cells, a recombinant expression vector containing full-length human AIRE cDNA was transfected into 16HBE cells. After incubation with transfected 16HBE cells, engulfment of apoptotic HL-60 cells induced by camptothecin was detected by myeloperoxidase (MPO) staining. The change in the expression of Rac 1 in transfected 16HBE cells was determined by RT-PCR and Western blotting. The results showed that the phagocytosis percentage of the experimental group, the mock transfection group and the negative control group (non-apoptotic cells) was (25.50+/-3.67)%, (6.25+/-1.58)% and (1.0+/-0.67)%, respectively. Moreover, the expressions of Rac 1 mRNA and protein were up-regulated in AIRE-transfected 16HBE cells, suggesting that AIRE may function as a regulator in the phagocytic clearance of apoptotic cells by promoting the expression of Rac 1.

Study on Fap1 glycosylation and maturation regulating by ORF3 coded by fap1-orf4 gene locus of Streptococcus parasanguis / 中华微生物学和免疫学杂志

Objective To study whether ORF3 coded by fap1-orf4 gene locus of Streptococcus pa-rasanguis is involved in the regulation of Fap1 glycosylation and maturation and to investigate whether ORF3 influences Streptococcus parasanguis adhesion. Methods A gene replacement strategy was adapted to con-struct orf3 alleic replace mutant of Streptococcus parasanguis. Complementation assay and Western blot were used to test Fap1 expression levels. Whole saliva-coated hydroxyapatite (SHA) adhesion assay was adapted to determine Streptococcus parasanguis adhension. Results (1) Non-polar was found in strain VT1774, the orf3 alleic replace mutant of Streptococcus parasanguis. (2) Western blot showed that mature Fapl (Mr about 220 × 103) disappeared and were substituted with high molecular weight Fapl (Mr about 470 × 103) in strain VT1774, furthermore, complementation assay showed VT1775, the complementation strain of VT1774, re-stored mature Fapl expression. (3) The binding ability reduced significantly in strain VT1774. Conclusion ORF3 coded byfapl-orf4 gone locus was required for Fap1 glycosylation and maturation in Streptococcus pa-rasanguis, orf3 alleic replacment resulted in Fap1 glycosylation and mature disorder and decreasing of adhen-sion ability of Streptococcus parasanguis.

Effects of BMI-1 over-expression on HOX family expression and cell cycle in HeLa cells / 中国病理生理杂志

AIM: To observe whether transfection of mammalian expression vector pEGFP containing the gene of B-cell specific moloney leukemia virus insertion site 1(BMI-1) could express in human cervix cancer cell line HeLa, and to detect its effect on HOX family expression and cell cycle.METHODS: pEGFP-BMI-1 was transfected into HeLa cells with Lipofectamine 2000. The expression of pEGFP-BMI-1 was determined by EGFP fluorescence and Western blotting. SYBR green I real-time RT-PCR was used to quantitate mRNA expression of P16~(INK4a), hTERT, HOXA9, HOXB4 and HOXC13. FACS analysis was used to detect the change of cell cycle.RESULTS: In HeLa cells transfected with pEGFP-BMI-1, the results of real-time RT-PCR showed that the mRNA expressions of P16~(INK4a), HOXA9 and HOXC13 were reduced to 9.2%, 10.9% and 69.7%, respectively, as compared to control HeLa cells (P<0.01). However, hTERT and HOXB4 mRNA expressions did not change significantly (P>0.05). FACS analysis showed a decrease from 65.68 % to 50.53% in G_1 population and a significant increase from 27.17% to 39.59 % in S population after transfection (P<0.01).CONCLUSION: BMI-1 over-expression in HeLa cells down-regulates mRNA expressions of P16~(INK4a), HOXA9 and HOXC13, decreases G_1 population and increases S population. Therefore, BMI-1 may be involved in carcinogenesis and cancer development.

Screening the mimotopes of blood group A antigen by phage display technology / 中华检验医学杂志

Objective To explore the peptides that can mimic the blood type A antigen and evaluate the anti-A antibody detection value of these peptides.Methods The anti-A monoclonal antibodv (NaM87-1F6)was used to panning the phage clones from a phage display 12-mer peptide library.Positive clones were identified by phage ELISA,phage mieropanning methods.Phage DNA Was sequenced and the corresponding peptide sequences were deduced.Agglutination inhibition test WaS performed to assess the ability of phage clones to inhibit the binding between the type A red blood cell and the anti-A antibody. ABO-ELISA based on the selected peptides was compared with classical haemagglutination test jn the detection of senlm anti-A antibody.Results Seven positive clones were chosen after panning,phage ELISA and phage micropanning.Six clones displayed peptide EYWYCGMNRTGC(C5),the other one displayed peptide QIWYERTLPFTF(C17).The phages displaying the selected peptides could specifically inhibit agglutination of type A red blood cells(RBCs)by anti-A antibodies.In the ABO-ELISA based on C5 and C17,the receiver operating characteristic(ROC)Curve showed that area under curve(AUC)were 0.889 (P=0.000),0.75l(P=0.000)respectively.The Spearman correlation Coeffieient between the ABO-EliSA value and the antibody titer derived from haemagglutination assay were 0.743(P<0.01),0.664(P<0.01)respectively.As for C5,0.300 was the best cut-off for ABO-ELISA with 82.2% sensitivity and 83.3% specificity.As for C17,the sensitivity and specificity of ABO-ELISA was 68.9% and 63.3% respectively when the cut-off value was 0.250.Conclusions The peptides EYWYCGMNRTGC and QIWYERTLPFTF can mimic the blood type A antigenic epitope.ABO-ELISA based on these peptides has the potential for the detection of anti-A antibody.