1.Clinical application of circulating microRNA in laboratory medicine
Chinese Journal of Laboratory Medicine 2011;34(10):865-870
microRNA(miR) in body fluids shows good stability and the change in its expression profile and level is associated with cancer and other diseases.Thus,circulating miR has been proposed to be an useful biomarker in diagnosis of the onset,prognosis and risk of diseases.Although great discoveries have been obtained on all aspects of miR,there are some shortcomings existing in the present studies,such as inconsistent specimens,diverse detection methods,lack of standardization on data analysis and other defects,resulting in poor reproducibility of data and inconsistent clinical conclusion,that make circulating miR difficult to be used in clinical laboratory testing.So lots of work is needed for us to implement,such as standardizing sample selection,improving detection reagents and methods,and normalizing test results before we can ultimately establish a fast,easy,low-cost detection of circulating miR in the clinical laboratory.
2.Analysis,identification and strategies on interferences in immunoassay
Gusheng TANG ; Yu WU ; Qian SHEN
Chinese Journal of Laboratory Medicine 2009;32(7):725-729
Substances that might potentially alter the measurable concentration of the analyte or alter the binding ability of detection antibody can lead to immunoassay interference. Endogenous interferences consist of autoantibodies, heterophiles antibodies, human anti-animal antibodies (HAAA) and some binding proteins. Lipidemia, cross-reactivity, pre-analytical variation, matrix and different detection equipments may also affect immunoassay. These interfering substances may cause falsely increased or decreased concentration in many analytes, including hormones, tumor markers, drugs, cardiac tropanin and microbial serology, thus it will affect the diagnosis of patients and the evaluation of therapeutic strategies Laboratorians and physicians should both be aware of the potential interference in immunoassays and communicate closely when any clinical discordance between the clinical and the laboratory data appears, avoiding a subsequent wrong diagnosis and unwarranted treatment. In this case, an alternative assay or measurement is needed for the potential correct results.
3.Laboratory developed tests in the development of modern medicine: opportunities and challenges
Yu WU ; Gusheng TANG ; Qian SHEN
Chinese Journal of Laboratory Medicine 2015;38(1):10-12
Translational medicine and personalized medicine are becoming the new power in modem medical development.Laboratory Developed Tests (LDTs) based on molecular biology and bioinformatics technology play a vital role in the development process of translational medicine and personalized medicine.Nowadays,LDTs consist of a broad range of in vitro diagnositc tests performed to analyze nucleic acid,chromosomes,proteins,certain metabolites and cell surface molecules using immunological technique,cytogenetic or molecular methods or a combination of these methods.These LDTs are used to detect heritable or acquired disease-related genotypes,mutations,or phenotypes,and also used to classify the pathological changes of cells for clinical purposes.New generation LDTs,present some unique regulatory questions still remain to be discussed.Clinicians should capture the opportunity to establish and continuously improve the detection platforms of LDTs,the quality control system and management standards.On this basis,transformation bridges between scientific research and clinical application will be truly built.
4.Adjusting method for data obtained from different biochemical analyzers
Yun LIN ; Jianrong ZHANG ; Qian SHEN ; Gusheng TANG
Academic Journal of Second Military Medical University 2000;0(08):-
Objective To evaluate and eliminate the potential bias between data obtained from dry and liquid biochemical assays,making data obtained by different assays matchable.Methods Bias estimation was performed based on document EP9-A2.Simple data comparison and methodology validation were performed after the experiment methods were modified with the estimated correction factors and interception.All the collected data were analyzed by EXCEL2007 software.Results The predicted bias of 4 of the 10 compared items exceeded their corresponding acceptable bias.After being adjusted by the coefficient and interception obtained from linear regression analysis,the four bias was improved and was within the acceptable range.The results of simple data comparison further confirmed this comparability.Conclusion Based on EP9-A2,we have established a protocol to obtain a consistency of data from different biochemical analyzers,which makes it possible that the detection results of the same patient from different detection systems can be used directly.The protocol has been approved by the experts during the medicinal laboratory accreditation of ISO15189.
5.Value of serum IgG4 in diagnosis of IgG4-related disease and in differentiation from rheumatic diseases
Zhengwen HE ; Gusheng TANG ; Qiong LU ; Qian SHEN
Chinese Journal of Laboratory Medicine 2012;(11):1029-1033
Objective To investigate the value of serum IgG4 in diagnosis of IgG4-RD and in differentiation from rheumatic diseases.Methods Total of 23 patients with IgG4-RD and 502 patients with rheumatic diseases were enrolled,who presented at Changhai Hospital in 2010 to 2011.In the study,rheumatic diseases were categorized into groups of Sj(o)gren syndrome (n =26),ankylosing spondylitis (n-50),systemic sclerosis (n =3),rhcumatoid arthritis (RA,n =125),mixed connective tissue disease (n =15),systemic lupus erythematosus (SLE,n =212),adult onset still disease (n =20),Behcet syndrome (n =17),polymyositis (n =12),dermatomyositis (n =12),polymyalgiarheumatica (n =10).Serum IgG and IgG4 levels were measured by a rate nephelometer assay.The ROC curves were constructed to identify the optimal serum IgG4 cutoff value for diagnosing IgG4-RD and evaluate its sensitivity and specificity.Results The mean levels of serum lgG4 in the group with IgG4-RD were 11.4(5.0-14.8) g/L.In about 95.6% IgG4-RD patients,the serum IgG4 level was higher than > 1.4 g/L and other rheumatic diseases (U values were 6.0,21.0,0,58.5,0,9.0,3.0,4.0,0,3.0,3.5,P <0.01).The levels of serum IgG4 with RA was 0.6(0.3-1.2) g/L,the levels of serum IgG4 with SLE was 0.2 (0.1-0.4) g/L.There were statistical differences between RA and SLE (U value was 5847,P < 0.01).At the same time,some patients with other rheumatic diseases were found serum IgG4 level higher than > 1.4 g/L,which was about 10% in the patients whith RA,ankylosing spondylitis,adult onset still disease and polymyalgiarheumatica.According to the ROC constructed the cut off value in present study was 2.2 g/L,and sensitivity and specificity were 95.7% and 97.4%,respectively.Area under the cerve (AUC) was 0.995.There were no significant differences between the sensitivity and specificity values obtained with a cutoff value of 2.2 g/L.In patients with other rheumatic diseases,the ratio of high serum IgG4 level (> 2.2 g/L) were declined obviously,except polymyalgiarheumatica,it was less than 10%.For differentiation from rheumatic diseases specificity values were higher.Conclusions The cut off value of 2.2 g/L is useful for diagnosing IgG4-RD,and in differentiation from rheumatic diseases.The high serum IgG4 concentrations are not specific to IgG4-RD.The cut off value of 2.2 g/L is better to diagnose IgG4-RD,and contributes to the differential diagnosis of IgG4-RD and other rheumatic diseases,but it needs to be further confirmed in clinical practice.
6.Disfunction of the dendritic cells from the aquaporin 5 knockout mice
Guifang WANG ; Gusheng TANG ; Chunling DONG ; Qian SHEN ; Chunxue BAI
Chinese Journal of Microbiology and Immunology 2008;28(4):299-302
Objective To investigate the effect of aquaporin 5(AQP5)gene to the differentiation and development of bone marrow-deriued dendritic cells(BMDC).Methotis The DCs obtained from the bone marrow of the AQP5-/- and the wild type(WT)mice were cultured and induced to maturation by LPS.The phenotype of the two types DCs were assayed by FACS,and the phagocytosis ability Was assayed by co-incubating with FITC-conjucted ovalbumin.Results Contrast to the DCs from the WT mice,the DCs from the A9P5-/-mice showed reducing positive rate of expression of the co-stimulating molecular such as CD40,CD80.CD86.And the phagoeytosis ability of DCs from the AOP5-/-mice was lower than that of the WT mice.The relationship of the phagncytosis rate to the time from the AOP5-/- mice was different from that of the WT mice.The stimulating ability of the AOP5-/-DCs was lower than that of the WT mice.Conclusion Water transmembrane moving mediated by AQP5 iS very important to the normal function of DCs.The certain mechanism of the signal moleeular is to be determined. Aquaporin 5;Dendritic cell;Gene knockout;Co-stimulating molecular
7.Negative interference of circulating troponin autoantibodies in five commonly used cardiac troponin Ⅰ detection systems
Yu WU ; Weiguo ZHAO ; Gusheng TANG ; Qian SHEN
Chinese Journal of Laboratory Medicine 2009;32(7):749-753
Objective To explore the possible negative interference of circulating cardiac troponin Ⅰ(cTnI) autoantibody on the immunoassay of cTnI in five commonly used cTnI detection systems. Methods Thirteen patients with positive cTnI autoantibodies in their serum samples were firstly screened and selected from 121acute myocardial infarction (AMI) patients using ELISA assay. The serum cTnI values and their recovery rates were then carefully measured and analyzed. Results cTnI values in these 13 samples showed amazing difference in the five detection systems, demonstrating various degrees of pseudo-drop, or even false-negative. One sample with low recovery was detected in Access-2 system. One sample with low recovery as well as one sample with moderate recovery were detected in Architect i2000 (Abbott). Two samples with moderate recovery and one sample with low recovery were detected in Axsym(Abbott). Three samples with moderate recovery and two samples with low recovery were detected in Dimension X Pand (Dade Behring)and one sample with moderate recovery together with four samples with low recovery were detected in Vidas (Biomerieux). And the serum levels of autoantibodies (A450) positively correlated with the degrees of their negative interference for the detection of cTnI. The R2 and P values on each system were 0. 841 (P <0. 01)vs Access-2, 0. 808 (P < 0. 01) vs Architect i2000 (Abbott), 0. 772 (P < 0. 01) vs Axsym (Abbott), 0. 707 (P < 0. 01) vs Dimension X Pand (Dade Behring) and 0. 424 (P < 0. 05) vs Vidas (Biomerieux), respectively. Conclusion Circulating autoantibodies of cTnI can induce considerable negative interference in all the 5 commonly used cTnI detection systems, which might then lead to incorrect judgments of the obtained results of cTnI in daily clinical work.
8.Characteristics of autoantibody and its perspectives for clinical diagnostics
Gusheng TANG ; Dongbao ZHAO ; Yu WU ; Qian SHEN
Chinese Journal of Laboratory Medicine 2012;35(3):193-196
Disease-associated autoantibodies (AAB) are important for the diagnosis of respective autoimmune diseases (AID).Autoantibodies can also be used for monitoring of response to therapy and for prognostic purpose.However,significant biological heterogeneity of autoantibody response,the difficulty in simultaneously improving detection sensitivity and specificity of autoantibodies and the lack of standardization in detection methods lead to limitations in its clinical applications and some difficulties in explaining the test results.It is important to search for novel autoantibodies in sera,to establish and standardize automated detection platforms with good quality and to perform well-designed clinical evaluation in the future research and clinical applications of autoantibodies.
9.Establishment of the CD19-K562 cell line over-expressing stably CD19 gene and its subcutaneous xenograft model in NOD-SCID mouse
Yang WANG ; Hui CHENG ; Keting CHEN ; Miaoxia HE ; Jie RUAN ; Gusheng TANG ; Jianmin YANG
Journal of Leukemia & Lymphoma 2015;24(12):715-721
Objective To construct a MigR1-CD19 recombinant vector which contains CD19 gene, and to establish a CD19-K562 cell line over-expressing stably CD19 gene and its subcutaneous xenograft model in NOD-SCID mouse.Methods The CD19 gene was inserted into the retroviral vector (MigR1) through recombinant DNA technology after transfection into Plat-A packaging cells, and viral supernatant was collected to transduce K562 cell line repeatedly to obtain stable transduction CD19-K562 cell line.Flow cytometry was used to determine the transduction efficiency and RT-PCR was used to confirmed CD19 gene expression.Cell proliferation and apoptosis were detected by cell count and Annexin V/PI, respectively.Then the subcutaneous xenograft subtype of CD19-K562-a cell line was constructed through subcutaneous inoculation and was cultured in vitro and in vivo.Then its subcutaneous xenograft model in NOD-SCID mouse was established.The characteristics of CD19-K562-a cells were detected by RT-PCR, Wright staining and immunohistochemistry.Results MigR1-CD19 recombinant vector was successfully constructed, and the CD19 positive efficiency of K562 cell line was (99.80±0.17) % through retrovirus centrifugation transduction.The transduction and passage had no effects on proliferation and apoptosis of CD19-K562 cells.The CD19-K562-a cell line was constructed after CD19-K562 cells were injected subcutaneously and were passaged in vitro and in vivo.The CD19 positive efficiency of the xenograft subtype CD19-K562-a cell line was (99.78± 0.04) %.CD19-K562-a and CD19-K562 cells were in an undifferentiated state.NOD-SCID subcutaneous xenografts were established through subcutaneous inoculation of CD19-K562-a cells.CD19 in the CD19-K562-a subcutaneous xenografts was positive, while it was negative in its counterparts K562 cells.Conclusion The CD19-K562 cell line over-expressing CD19 gene and its subcutaneous xenograft model in NOD-SCID mouse are successfully established.
10.Acute lymphoblastic leukemia with atypical bcr-abl rearrangement: a case report and literature review
Shenglan GONG ; Gusheng TANG ; Mengqiao GUO ; Huiying QIU ; Lei GAO ; Hui CHENG ; Jianmin WANG
Journal of Leukemia & Lymphoma 2015;24(6):352-355
Objective To investigate the detection methods of atypical bcr-abl rearrangement with b3a3 fusion transcript,and to describe the characteristics of this fusion gene.Methods Karyotype analysis,FISH and RT-PCR were applied to detect the break point of bcr-abl fusion gene in a patient who was diagnosed as acute lymphoblastic leukemia.Results The karyotype of the patient was expressed as 45,XY,-7,t(9;22)(q34;q1 1).The translocation event in chromosome 9 and 22 could be successfully detected by FISH,and a rare bcr-abl rearrangement with b3a3 fusion transcript was detected by RT-PCR with specific primers.Conclusions The rare e14a3 (b3a3) fusion of bcr-abl gene is present in this patient.Clinical laboratories using commercial kits that do not cover such rare fusions are likely to generate false result,thereby declaring combination of various methods to detect fusion genes is necessary.More studies are needed to explore the function and significance of rare bcr-abl fusion genes.