Autoimmune diseases had become the burthen of human health.We present the clinic value of autoantibodies detection in autoimmune diseases diagnosis and differential diagnosis,illness assessment and therapy monitor,disease transformation and prognosis estimation.We also presented some advice on clinic appliance of autoantibodies detection and quality assurance.

The immunoglobulin G (IgG),a major effective molecule of the humoral immune response in man,comprising four different subclasses IgG1,IgG2,IgG3 and IgG4.Deficiency and imbalance of IgG subclasses are an indication of a disturbed immune response.The four IgG subclasses play a different role in the development of diseases.As well understanding of IgG and IgG subclasses in recent years,especially after the definition and study of IgG4 related disease,the clinical significance of IgG subclasses are getting the international concern and attention.

IgG4-related diseases are a class of chronic,progressive,systemic inflammatory disorders that are characterized by lymphoplas-macytic inflammation,as well as elevated IgG4 levels in serum and tissue,and may involve multiple organs or tissues.When involving the pancreas,liver,and biliary tracts,they are called IgG4-related hepatobiliary diseases.IgG4-related autoimmune pancreatitis,IgG4-re-lated sclerosing cholangitis,and IgG4-associated autoimmune hepatitis are reviewed in terms of their clinical manifestations and laboratory findings.Accurate identification of the laboratory results for IgG4-related hepatobiliary diseases and correct diagnosis of these diseases help to avoid unnecessary surgery and wrong treatment.

The detection of autoantibodies is of great value in the diagnosis and treatment of autoimmune diseases.The popular autoantibody screening promotes the rapid development of the clinical awareness,diagnosis and treatment of autoimmune diseases,which in turn results in the increasing demand of autoantibody detection and continuous improvement the detection quality.In order to make better use of autoantibodies results during the diagnosis and treatment of autoimmune diseases,the workers of autoantibodies detection should understand various affecting factors of the autoantibodies detection completely,emphasis on the autoantibodies quality management and improve the quality of detection constantly ; Aware of the complexity and specificity of autoantibodies fully and participate in the selection of autoantibodies detection and correct interpretation of the clinical significance of autoantibodies actively;Emphasis on the clinical application of autoantibodies and promote the universal clinical application of autoantibodies.

Copy number variation (CNV) is one kind of structural variations,which exists extensively in human genome.In addition,it is the crucial source of inter-individual gene differences.Recently,with the successful development of gene array and gene sequencing,molecular methods for CNV testing are more and more standardizing and automating.Therefore,ongoing attentions have been attached to the effects and mechanisms of CNV in complicated diseases like autoimmune diseases.Molecular methods for CNV testing can be divided into two categories:target screening and the whole genome scanning platforms.Currently,the studies about CNV and autoimmune diseases mainly focused on systemic lupus erythematosus and rheumatoid arthritis.Considering the limitations of measurement methods and testing costs,it is still in the infant.

The detection of autoimmune liver disease (AILD) relevant autoantibodies is of important value in the diagnosis and treatment of AILD and especially in autoimmune hepatitis and primary biliary cirrhosis.With the increasing of patients clinically diagnosed AILD,the detection of AILD relevant autoantibodies is gradually clinically concerned and appreciated.As the detection of AILD relevant autoantibodies affected by various factors,there are still many problems in the detection and clinical applications of AILD relevant autoantibodies.We should promote the universal clinical application of AILD relevant autoantibodies,emphasis on the quality management and improve the quality of detection constantly,attend to the standard detection and rational application of AILD relevant autoantibodies.

Antiphospholipid antibodies (APLs) are important for the diagnosis of antiphospholipid syndrome (APS),especially for predicting the risk of thrombosis and pathological pregnancy.However,the heterogeneity of antiphospholipid antibodies,lacking of standardization and significant interlaboratory variation binder the clinical application of APLs and better understanding of APS diagnosis and treatment.Therefore,it is urgent to establish a standardize system for antiphospholipid antibodies test and to improve the performance of the test and perform well-designed clinical evaluation.

According to the consensus criteria of antiphospholipid syndrome (APS),the diagnosis of APS requires the persistent presence of antiphospholipid antibodies (aPLs),indicating the critical role of aPLs in the diagnosis of APS.During the last decade,great efforts have been made to improve the laboratory detection and standardization of aPLs testing.Unfortunately,the heterogeneous nature of aPLs,lacking of standardization in aPLs test,and significant inter-laboratory variation have hampered the clinical application of aPLs test.In this commentary,the clinical application and standardization of aPLs test are focused on,and how to establish the standardization system in aPLs test in order to improve the performance of aPLs test in clinical practice are discussed.

Objective:To detect anti-LKM-1 antibody with enzyme-linked immunosorbent assay (ELISA) using a recombinant fusion peptide which comprises 257-351 amino acid fragment of CYP2D6 as antigen.Methods:We obtained CYP2D6 cDNA fragment by means of PCR,using total liver cDNA library as the template.The PCR products were ligated into pEGH expressing vector to construct the recombinant expressing vector with high efficiency in Saccharomyces Cerevisiae Y258.The positive clones were identified by PCR reaction and then induced by galactose.Glutathione-Sepharose 4B was used for purification of recombinant CYP2D6 protein.After affinity purification,the antigenicity was identified with Western blot.Serum samples from 26 patients who were positive for anti-LKM-1 antibody,20 patients with other connective tissue disorder(CTD) and 30 normal controls were retrospectively tested with ELISA.Results:A fusion peptide was expressed and purified.The antigenicity was confirmed with Western blot using standard of anti-LKM-1 antibody-positive serum.Of the 26 serum samples which are positive for anti-LKM-1 antibody,5 of 6 samples positive for anti-HCV antibody also recognized the recombinant fusion peptide with ELISA,only one serum sample which was showed positive anti-HCV antibody displayed a negative result in ELISA assay.All other 20 patients with positiv anti-LKM-1 antibody were shown positive in ELISA assay using this recombinant peptide.All the serum samples from patients with other CTD were negative in ELISA assay.Conclusion:The recombinant antigen fragment contains major epitope regions in natural CYP2D6 antigen.Detection of anti-LKM-1 antibody with ELISA using the recombinant peptide can improve the sensitivity and has a potential role in determining its clinical association.

Objective To study the influence of sampling,handling,shipping and storage on low-molecular-weight serum proteome profiling.Methods Serum samples instantly separated and aliquoted,some stored at-80 ℃ for up to 6 months,others stored at 4 ℃ or room temperature(25 ℃) for 2 to 72 hrs.The variations of protein profiling under these conditions on WCX magnetic beads were studied.Profiling influenced by hemolysis,multi freeze-thaw cycles,storage conditions.Results Different handling procedures and storage conditions have different effects on serum profiling.Serum stored at-80 ℃ up to 6 months,stored at 4 ℃ or 25 ℃ for 2 h or one freeze-thaw cycle,had little effects on serum proteomic analysis.If serum diluted into 9 mol/L urea buffer at room temperature,the result is stable for 24 hours.Statistics analysis shows that 35.9% peaks have significant changes(P