Enzyme-linked immunosorbent assay of 3 Screen Islet Cell Autoantibody in patients with autoimmune thyroid disease

BACKGROUND In recent years,the emergence of multiplex technology that can simultaneously measure multiple anti-islet autoantibodies has become particularly valuable for the staging and early diagnosis of immune-mediated type 1 diabetes(T1D).While it has been established that 20%-30%of T1D patients suffer from autoimmune thyroid disease(AITD),there is limited available data regarding the presence of anti-islet autoantibodies in AITD patients.Among commercially available anti-islet autoantibodies,glutamic acid decarboxylase 65 autoantibodies(GADAs)are often the first marker measured in general clinical practice.AIM To investigate the frequency of anti-islet autoantibodies in AITD patients.METHODS Our study involved four hundred ninety-five AITD patients,categorized into three distinct groups:AITD with T1D(n=18),AITD with phenotypic type 2 diabetes(T2D)(n=81),and AITD without diabetes(n=396),and the enzyme-linked immunosorbent assay(ELISA)was employed to determine the frequencies of 3 Screen Islet Cell Autoantibody(3 Screen ICA),GADA,insulinoma-associated antigen-2 autoantibodies(IA-2As),and zinc transporter 8 autoantibodies(ZnT8As)within these groups.RESULTS The frequency of 3 Screen ICA in AITD patients with T1D,T2D,and those without diabetes were 88.9%,6.2%,and 5.1%,respectively,with no significant difference seen between the latter two groups.Notably,the frequency of 3 Screen ICA was 11.1%higher in AITD patients with T1D,1.3%higher in AITD patients with T2D,and 1.1%higher in AITD patients without diabetes compared to GADA,respectively.Furthermore,12.5%,20.0%,and 20.0%of the 3 Screen ICA-positive patients were negative for GADA.Additionally,1.3%of the AITD patients who tested negative for 3 Screen ICA in both the AITD with T2D and non-diabetic AITD groups were found to be positive for individual autoantibodies.Among the 3 Screen ICA-positive patients,there was a significantly higher proportion of individuals with multiple autoantibodies in AITD patients with T1D compared to those without diabetes(37.5%vs 5.0%,P<0.05).However,this proportion was similar to that in AITD patients with T2D(20.0%).Nevertheless,there was no significant difference in 3 Screen ICA titers between AITD patients with T1D and those without diabetes(436.8±66.4 vs 308.1±66.4 index).Additionally,no significant difference in 3 Screen ICA titers was observed between Graves’disease and Hashimoto’s thyroiditis in any of the groups.CONCLUSION Our findings reveal that some AITD patients without diabetes exhibit 3 Screen ICA titers comparable to those in AITD patients with T1D.Thus,3 Screen ICA outperforms GADA in identifying latent anti-islet autoantibody-positive individuals among AITD patients.

Profile of Autoantibodies and Clinical Symptoms in Guinean Patients with Connective Tissue Diseases

Connective tissue diseases (CTDs) are Autoimmune diseases (AIDs) characterized by the appearance of autoantibodies, which are diagnostic markers. Investigations of these autoantibodies play a major role in the management of several autoimmune diseases. The objective of this study was to describe the profile of anti-ENA antibodies according to the clinical symptoms of mixed CTDs in Conakry teaching Hospital. We performed a cross-sectional study during six months. A total of 20 patients was recruited and we measured antibodies using the ELISA technique. The mean age of our patients was 36.5 years, with a predominance of females. Cutaneous and rheumatological signs were the main clinical manifestations. SLP was the most frequent CTDs;the threshold of ENA antibodies positivity was higher in scleroderma with and SLP. Anti-ENA identification reveals the frequency of anti-SSA (83.33%), anti-U1RNP (66.66%) and anti-histone (50%) antibodies. Antinuclear antibodies (ANA) react with various components of the cell nucleus. Their detection is of major interest in the diagnosis of CTDs. Our results highlight the importance of determining the specificity of these antibodies to guide differential diagnosis.

Autoantibodies related to ataxia and other central nervous system manifestations of gluten enteropathy

Gluten ataxia and other central nervous system disorders could be linked to gluten enteropathy and related autoantibodies.In this narrative review,we focus on the various neuro-logical manifestations in patients with gluten sensitivity/celiac disease,immunological and autoimmune mechanisms of ataxia in connection to gluten sensitivity and the autoantibodies that could be used as a biomarker for diagnosing and following.We focused on the anti-gliadin antibodies,antibodies to different isoforms of tissue transglutaminase(TG)(anti-TG2,3,and 6 antibodies),anti-glycine receptor antibodies,anti-glutamine acid decarboxylase antibodies,anti-deamidated gliadin peptides antibodies,etc.Most studies found a higher prevalence of these antibodies in patients with gluten sensitivity and neurological dysfunction,presented as different neurological disorders.We also discuss the role of a gluten-free diet on the clinical improvement of patients and also on imaging of these disorders.

Autoantibodies in Chinese patients with chronic hepatitis B:Prevalence and clinical associations

AIM: To investigate the prevalence of autoantibodies and their associations with clinical features in Chinesepatients with chronic hepatitis B(CHB).METHODS: A total of 325 Chinese patients with CHB were enrolled in this retrospective,hospitalbased study.Patients with chronic hepatitis C(CHC),autoimmune hepatitis(AIH),or primary biliary cirrhosis(PBC) were included,with healthy donors acting as controls.A panel of autoantibodies that serologically define AIH and PBC was tested by indirect immunofluorescence assay and line immunoassay.The AIH-related autoantibody profile included homogeneous anti-nuclear antibodies(ANA-H),smooth-muscle antibodies,anti-liver kidney microsome type 1,antiliver cytosolic antigen type 1,and anti-soluble liver antigen/liver pancreas; the PBC-related antibodies were characterized by ANA-nuclear dots/membranous rimlike,anti-mitochondrial antibodies-M2(AMA-M2),antiBPO(recombinant antigen targeted by AMA-M2),antiSp100,anti-promyelocytic leukemia protein(anti-PML),and anti-gp210.The dichotomization of clustering was used to unequivocally designate the AIH or PBC profiles for each case.Anti-Ro52 antibodies were also tested.RESULTS: The prevalence of any autoantibody in CHB amounted to 58.2%,which was similar to the 66.2% prevalence in CHC,significantly higher than the 6.7% in the healthy controls(P < 0.001),and lower than the 100% found in AIH and PBC(P = 0.004 and P < 0.001,respectively).There were more anti-PML and anti-gp210 antibodies among the CHB patients than the CHC patients(11.1% vs 0%,P = 0.003; 12.6% vs 0%,P < 0.001,respectively).The prevalence and titer of AMA,anti-BPO,anti-PML,and anti-gp210 were higher in PBC than in those with CHB.Among the CHB patients,the prevalence of ANA,especially ANA-H,was significantly lower in patients with compensated and decompensated cirrhosis compared with patients without cirrhosis.Thirty-eight cases of hepatocellular carcinoma(HCC) in CHB showed a significant differencecompared with non-HCC patients in the prevalence of anti-PML(0% vs 12.5%,P = 0.013).Dichotomization of the autoantibodies revealed that the PBC profile was more prevalent in patients with CHB than in those with CHC,and that it was strongly correlated with both compensated and decompensated cirrhosis.In contrast,the prevalence of the AIH profile was significantly higher in non-cirrhosis patients with CHB than in those with compensated cirrhosis(18.5% vs 8.2%,P = 0.039).Moreover,the AIH profile was also closely associated with hepatitis B e-antigen positivity.CONCLUSION: ANA-H could be an indicator of earlystage CHB.Dichotomizing the autoantibody profiles revealed that the PBC profile is strongly associated with cirrhosis in CHB.

Autoantibodies in primary biliary cirrhosis:Recent progress in research on the pathogenetic and clinical significance

Primary biliary cirrhosis(PBC)is a chronic progressive cholestatic liver disease characterized by immunemediated destruction of the small-and medium-sized intrahepatic bile ducts and the presence of antimitochondrial antibodies(AMA)in the serum.AMA are detected in over 90%of patients with PBC,whereas their prevalence in the general population is extremely low,varying from 0.16%to 1%.Previous studies have shown that the unique characteristics of biliary epithelial cells undergoing apoptosis may result in a highly direct and very specific immune response to mitochondrial autoantigens.Moreover,recent studies have demonstrated that serum from AMA-positive PBC patients is reactive with a number of xenobiotic modified E2 subunits of the pyruvate dehydrogenase complex,which is not observed in the serum of normal individuals.These findings indicate that chemicals originating from the environment may be associated with a breakdown in the tolerance to mitochondrial autoantigens.While it is currently generally accepted that AMA are the most specific serological markers of PBC,more than 60 au-toantibodies have been investigated in patients with PBC,and some have previously been considered specific to other autoimmune diseases.This review covers the recent progress in research on the pathogenetic and clinical significance of important autoantibodies in PBC.Determining the pathogenic role of those autoantibodies in PBC remains a priority of basic and clinical research.

Primary biliary cirrhosis:What do autoantibodies tell us?

Primary biliary cirrhosis(PBC) is a chronic,progressive,cholestatic,organ-specific autoimmune disease of unknown etiology.It predominantly affects middle-aged women,and is characterized by autoimmune-mediated destruction of small-and medium-size intrahepatic bile ducts,portal inflammation and progressive scarring,which without proper treatment can ultimately lead to fibrosis and hepatic failure.Serum autoantibodies are crucial tools for differential diagnosis of PBC.While it is currently accepted that antimitochondrial antibodies are the most important serological markers of PBC,during the last five decades more than sixty autoantibodies have been explored in these patients,some of which had previously been thought to be specific for other autoimmune diseases.

Autoantibodies against tumor-associated antigens for detection of hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is one of the most common tumors worldwide. The survival rate after the onset of symptoms is generally less than one year for the late presentation of HCC, and reliable tools for early diagnosis are lacking. Therefore, novel biomarkers for the early detection of HCC are urgently required. Recent studies show that the abnormal release of proteins by tumor cells can elicit humoral immune responses to self-antigens called tumor-associated antigens(TAAs). The corresponding autoantibodies can be detected before the clinical diagnosis of cancer. Therefore, there is growing interest in using serum autoantibodies as cancer biomarkers. In this review, we focus on the advances in research on autoantibodies against TAAs as serum biomarker for detection of HCC, the mechanism of the production of TAAs, and the association of autoantibodies with patients' clinical characteristics.

Autoimmune liver disease-related autoantibodies in patients with biliary atresia

AIM To investigate the prevalence and clinical significance of autoimmune liver disease(ALD)-related autoantibodies in patients with biliary atresia(BA).METHODS Sera of 124 BA patients and 140 age-matched non-BA controls were assayed for detection of the following autoantibodies: ALD profile and specific anti-nuclear antibodies(ANAs), by line-blot assay; ANA and antineutrophil cytoplasmic antibody(ANCA), by indirect immunofluorescence assay; specific ANCAs and antiM2-3 E, by enzyme linked immunosorbent assay. Associations of these autoantibodies with the clinical features of BA(i.e., cytomegalovirus infection, degree of liver fibrosis, and short-term prognosis of Kasai procedure) were evaluated by Spearman's correlation coefficient.RESULTS The overall positive rate of serum autoantibodies in preoperative BA patients was 56.5%. ALD profile assay showed that the positive reaction to primary biliary cholangitis-related autoantibodies in BA patients was higher than that to autoimmune hepatitis-related autoantibodies. Among these autoantibodies, anti-BPO was detected more frequently in the BA patients than in the controls(14.8% vs 2.2%, P < 0.05). Accordingly, 32(25.8%) of the 124 BA patients also showed a high positive reaction for anti-M2-3 E. By comparison, the controls had a remarkably lower frequency of anti-M2-3 E(P < 0.05), with 6/92(8.6%) of patients with other liver diseases and 2/48(4.2%) of healthy controls. The prevalence of ANA in BA patients was 11.3%, which was higher than that in disease controls(3.3%, P < 0.05), but the reactivity to specific ANAs was only 8.2%. The prevalence of ANCAs(ANCA or specific ANCAs) in BA patients was also remarkably higher than that in the healthy controls(37.9% vs 6.3%, P < 0.05), but showed no difference from that in patients with other cholestasis. ANCA positivity was closely associated with the occurrence of postoperative cholangitis(r = 0.61, P < 0.05), whereas none of the autoantibodies showed a correlation to cytomegalovirus infection or the stages of liver fibrosis.CONCLUSION High prevalence of autoantibodies in the BA developmental process strongly reveals the autoimmunemediated pathogenesis. Serological ANCA positivity may be a useful predictive biomarker of postoperative cholangitis.

Autoantibodies: Potential clinical applications in early detection of esophageal squamous cell carcinoma and esophagogastric junction adenocarcinoma

Esophageal squamous cell carcinoma(ESCC)and esophagogastric junction adenocarcinoma(EGJA)are the two main types of gastrointestinal cancers that pose a huge threat to human health.ESCC remains one of the most common malignant diseases around the world.In contrast to the decreasing prevalence of ESCC,the incidence of EGJA is rising rapidly.Early detection represents one of the most promising ways to improve the prognosis and reduce the mortality of these cancers.Current approaches for early diagnosis mainly depend on invasive and costly endoscopy.Non-invasive biomarkers are in great need to facilitate earlier detection for better clinical management of patients.Tumor-associated autoantibodies can be detected at an early stage before manifestations of clinical signs of tumorigenesis,making them promising biomarkers for early detection and monitoring of ESCC and EGJA.In this review,we summarize recent insights into the iden-tification and validation of tumor-associated autoantibodies for the early detection of ESCC and EGJA and discuss the challenges remaining for clinical validation.

Anti-rods/rings autoantibody generation in hepatitis Cpatients during interferon-α/ribavirin therapy

Chronic inflammation associated with hepatitis C virus(HCV) infection can lead to disabling liver diseases with progression to liver cirrhosis and hepatocellular carcinoma. Despite the recent availability of more effective and less toxic therapeutic options, in most parts of the world the standard treatment consists of a weekly injection of pegylated interferon α(IFN-α) together with a daily dose of ribavirin. HCV patients frequently present circulating non-organ-specific autoantibodies demonstrating a variety of staining patterns in the indirect immunofluorescence assay for antinuclear antibodies(ANA). Between 20% to 40% of HCV patients treated with IFN-α and ribavirin develop autoantibodies showing a peculiar ANA pattern characterized as rods and rings(RR) structures. The aim of this article is to review the recent reports regarding RR structures and anti-rods/rings(antiRR) autoantibody production by HCV patients after IFN-α/ribavirin treatment. Anti-RR autoantibodies first appear around the sixth month of treatment and reach a plateau around the twelfth month. After treatment completion, anti-RR titers decrease/disappear in half the patients and remain steady in the other half. Some studies have observed a higher frequency of anti-RR antibodies in relapsers, i.e., patients in which circulating virus reappears after initially successful therapy. The main target of anti-RR autoantibodies in HCV patients is inosine-5'-monophosphate dehydrogenase 2(IMPDH2), the rate-limiting enzyme involved in the guanosine triphosphate biosynthesis pathway. Ribavirin is a direct IMPDH2 inhibitor and is able to induce the formation of RR structures in vitro and in vivo. In conclusion, these observations led to the hypothesis that anti-RR autoantibody production is a human model of immunologic tolerance breakdown that allows us to explore the humoral autoimmune response from the beginning of the putative triggering event: exposure to ribavirin and interferon.

Autoantibodies to apolipoprotein A-1 as a biomarker of cardiovascular autoimmunity

Immune-driven inflammation plays an important part inatherogenesis and is therefore believed to be key to thedevelopment of cardiovascular disease(CVD), whichis currently the leading cause of death in the Westernworld. By fulfilling some of the Koch postulates, athero-genesis has even been proposed to be considered as anautoimmune disease, raising the hope that CVD couldbe prevented by immunomodulation. Nevertheless,the role of the immune system and autoimmune reac-tions in atherosclerosis appear to be a double edged-sword, with both pro-atherogenic and anti-atherogenicattributes. Hence, if immunomodulation is to becomea therapeutic option for atherosclerosis and CVD, it willbe crucial to correctly identify patients who might ben-efit from targeted suppression of deleterious autoim-mune responses. This could be achieved, for example, by the detection of disease-associated autoantibodies. In this work, we will review the currently available clini-cal, in vitro, and animal studies dedicated to autoan-tibodies against apolipoprotein A-1(anti-apoA-1 IgG), the major proteic fraction of high density lipoprotein. Current clinical studies indicate that high levels of anti-apoA-1 IgG are associated with a worse cardiovascular prognosis. In addition, in vitro and animal studies indi-cate a pro-inflammatory and pro-atherogenic role, sup-porting the hypothesis that these autoantibodies may play a direct causal role in CVD, and furthermore that they could potentially represent a therapeutic target for CVD in the future.

Circulating autoantibodies to endogenous erythropoietin are associated with chronic hepatitis C virus infection-related anemia

BACKGROUND： Chronic hepatitis C virus （HCV） infection is associated with autoimmune phenomena and is often complicated by anemia. Circulating autoantibodies to endogenous erythropoietin （anti-EPO） have been detected in patients with chronic viral infections and were correlated to anemia. The present study aimed to determine anti-EPO prevalence in pa- tients with chronic HCV infection and investigate its possible association with anemia. METHODS： Ninety-three consecutive patients （62 males and 31 females） with chronic HCV infection, who had never re- ceived antiviral therapy or recombinant EPO, were enrolled in the study. Circulating anti-EPO were detected in the serum by using an ELISA assay. Quantitative determination of serum EPO levels was done by radioimmunoassay. HCV RNA viral load t and genotype sequencing were also performed. RESULTS： Circulating anti-EPO were detected in 10.8% of HCV-infected patients and the prevalence of anti-EPO was significantly higher in patients with anemia （19.4% vs 5.3%, P=0.040） compared to that in those without anemia. Compared to anti-EPO negative cases, anti-EPO positive patients had higher frequency of anemia （70.0% vs 34.9%, P=0.030）, lower EPO concentrations （median 16.35 vs 30.65 mU/mL, P=0.005）, and higher HCV RNA viral load （median 891.5x103 vs 367.5x 103 IU/mL, P=0.016）. In multivariate regression anal- ysis the presence of anti-EPO remained an independent predictor of anemia （adjusted OR： 14.303, 95% CI： 1.417-36.580, P=0.024）. EPO response to anemia was less prominent among anti-EPO positive patients （P=0.001）. CONCLUSIONS： Circulating anti-EPO are detected in a significant proportion of treatment-naive HCV-infected patients and are independently associated with anemia, suggesting a further implication of autoimmunity in the pathophysiology of HCV-related anemia.

Experimental Study of Serum Substantia Nigra Neuron Autoantibody and Its Effect in Parkinson Disease Patients

To investigate the serum substantia nigra neuron autoantibody and its effect in the patients with Parkinson disease (PD), substantia nigra slices and a rat model of injection of serum from PD patients in unilateral side substantia nigra were applied. The results showed that the positive rate of substantia nigra neuron autoantibody in PD patients was significantly higher than in the healthy control group (36.67 % vs 6.67 %, P <0.01), but no significant difference was found between PD group and myasthenia gravis (MG) group (26.67 %, P >0.05). The sera from PD patients positive for substantia nigra neuron autoantibody could decrease the number of the dopaminergic neurons more seriously than those from MG and the healthy once respectively (both P <0.01). The results suggested that the immunological mechanism might partly play a role in the development of PD.

Tumor-associated autoantibodies are useful biomarkers in immunodiagnosis of α-fetoprotein-negative hepatocellular carcinoma

AIM To determine the prevalence and diagnostic value of autoantibodies inα-fetoprotein(AFP)-negative hepatocellular carcinoma(HCC).METHODS Fifty-six serum samples from AFP-negative HCC cases,86 from AFP-positive HCC cases,168 from chronic liver disease cases,and 59 from normal human controls were included in this study.Autoantibodies to nucleophosmin(NPM)1,14-3-3zeta and mouse double minute 2 homolog(MDM2)proteins in AFP-negative HCC serum were evaluated by enzymelinked im munosorbent assay.Partially positive sera were further evaluated by western blotting.Immunohistochemistry was used to detect the expression of three tumor-associated antigens(TAAs)in AFP-negative HCC and normal control tissues.RESULTS The frequency of autoantibodies to the three TAAs in AFP-negative HCC sera was 21.4%,19.6%and 19.6%,which was significantly higher than in the chronic liver disease cases and normal human controls(P<0.01)as well as AFP-positive HCC cases.The sensitivity of the three autoantibodies for diagnosis of AFP-negative HCC ranged from 19.6%to 21.4%,and the specificity was approximately 95%.When the three autoantibodies were combined,the sensitivity reached 30.4%and the specificity reached 91.6%.CONCLUSION Autoantibodies to NPM1,14-3-3zeta and MDM2 may be useful biomarkers for immunodiagnosis of AFP-negative HCC.

Impact of parietal cell autoantibodies and non-organ-specific autoantibodies on the treatment outcome of patients with hepatitis C virus infection: A pilot study

AIM: Various side effects have been reported in patients infected with hepatitis C virus (HCV) who were treated with interferon-alpha (IFN-α), including the appearance or exacerbation of underlying autoimmune diseases and the development of a variety of organ and non-organ specific autoantibodies (NOSA). However, very few studies in adults have been strictly designed to address: whether the prevalence and the titre of organ and NOSA in serial samples of HCV-treated patients were affected by IFN-α, and the impact of these autoantibodies on the treatment outcome of HCV patients. METHODS: We investigated whether parietal cell autoantibodies (PCA) and/or NOSA were related with treatment-outcome in 57 HCV-treated patients (19 sustained-responders, 16 relapsers, 22 non-responders). Serum samples from patients were studied blindly at three time-points (entry, end of treatment and end of followup). For the detection of autoantibodies we used indirect immunofluorescence, commercial and in-house ELISAs. RESULTS: Sustained biochemical response was associated with ANA-negativity at the entry or end of follow up. Sustained virological response was associated with the absence of PCA at the entry. Combined virological and biochemical sustained response (CVBSR) was associated with the absence of antinuclear antibodies (ANA) at the end of follow up and PCA-negativity at the entry. Sustained virological and CVBSR were associated with a reduction of ANA and SMA titers during therapy. CONCLUSION: Although PCA and/or NOSA seropositivity should not affect the decision to treat HCV patients, the presence of some of them such as ANA, PCA and SMA before treatment or their increase during therapy with IFN- a may predict a worse response, indicating the need for a closer monitoring during treatment of HCV patients positive for these autoantibodies.

Autoantibody profiles in autoimmune hepatitis and chronic hepatitis C identifies similarities in patients with severe disease

To determine how the auto-antibodies (Abs) profiles overlap in chronic hepatitis C infection (CHC) and autoimmune hepatitis (AIH) and correlate to liver disease.METHODSLevels of antinuclear Ab, smooth muscle antibody (SMA) and liver/kidney microsomal-1 (LKM-1) Ab and markers of liver damage were determined in the sera of 50 patients with CHC infection, 20 AIH patients and 20 healthy controls using enzyme linked immunosorbent assay and other immune assays.RESULTSWe found that AIH patients had more severe liver disease as determined by elevation of total IgG, alkaline phosphatase, total serum bilirubin and serum transaminases and significantly higher prevalence of the three non-organ-specific autoantibodies (auto-Abs) than CHC patients. Antinuclear Ab, SMA and LKM-1 Ab were also present in 36% of CHC patients and related to disease severity. CHC cases positive for auto-Abs were directly comparable to AIH in respect of most markers of liver damage and total IgG. These cases had longer disease duration compared with auto-Ab negative cases, but there was no difference in gender, age or viral load. KLM-1+ Ab CHC cases showed best overlap with AIH.CONCLUSIONAuto-Ab levels in CHC may be important markers of disease severity and positive cases have a disease similar to AIH. Auto-Abs might have a pathogenic role as indicated by elevated markers of liver damage. Future studies will unravel any novel associations between these two diseases, whether genetic or other.

Autoantibodies and hepatitis C virus genotypes in chronic hepatitis C patients in Estonia

AIM: To determine the prevalence of several autoantibodies in chronic hepatitis C patients, and to find out whether the pattern of autoantibodies was associated with hepatitis C virus (HCV) genotypes. METHODS: Sera from 90 consecutive patients with chronic hepatitis C were investigated on the presence of anti-nuclear (ANA), anti-mitochondrial (AMA), anti-smooth muscle (SMA), anti-liver-kidney microsomal type 1 (LKMA1), anti-parietal cell (PCA), anti-thyroid microsomal (TMA), and anti-reticulin (ARA) autoantibodies. The autoantibodies were identified by indirect immunofluorescence. HCV genotypes were determined by a restriction fragment length polymorphism analysis of the amplified 5' noncoding genome region. RESULTS: Forty-six (51.1%) patients were positive for at least one autoantibody. Various antibodies were presented as follows: ANA in 13 (14.4%) patients, SMA in 39 (43.3%), TMA in 2 (2.2%), and ARA in 1 (1.1%) patients. In 9 cases, sera were positive for two autoantibodies (ANA and SMA). AMA, PCA and LKMAI were not detected in the observed sera. HCV genotypes were distributed as follows: 1b in 66 (73.3%) patients, 3a in 18 (20.0%), and 2a in 6 (6.7%) patients. CONCLUSION: A high prevalence of ANA and SMA can be found in chronic hepatitis C patients. Autoantibodies are present at low titre (1:10) in most of the cases. Distribution of the autoantibodies show no differences in the sex groups and between patients infected with different HCV genotypes.

Presence of disease specific autoantibodies against liver sinusoidal cells in primary biliary cirrhosis

AIM: To investigate the presence of autoantibodies directed against liver sinusoidal cells in primary biliary cirrhosis(PBC).METHODS: Liver biopsies from 21 PBC patients were studied and compared with 12 liver biopsies from disease controls [3 patients with hepatitis B(HBV) virus,3 patients with hepatitis C virus(HCV), 3 patients with non-alcoholic steatohepatitis and 3 patients with acute alcoholic hepatitis(AAH)]. As healthy controls, we used tissue specimens adjacent to metastatic liver adenocarcinoma. Normal serum was taken from staff members of the unit. The determination of the cell type targetedby autoantibodies present in the patients sera was performed by indirect immunofluorescence(IIF) analysis using paraffin-embedded liver sections as a substrate.Sera from homologous or heterologous PBC patients or sera from the disease control group were used as primary antibodies. The presence of autoantibodies was identified using confocal microscopy.RESULTS: In total, 18/21(85.7%) PBC patients exhibited positive staining in the sinusoidal cells, 10/21(47.6%) in lymphocytes, 8/21(38%) in cholangiocytes and 7/21(33.3%) in hepatocytes, when homologous serum and fluorescein isothiocyanate-conjugated immunoglobulin type G(IgG) secondary antibody were used. PBC sections incubated with heterologous PBC serum showed reduced staining(20% for sinusoidal cells, 20% for lymphocytes, 20% for cholangiocytes and 13.3% for hepatocytes). When IgM immunoglobulin, instead of IgG, was used as secondary antibody,positive staining was observed in 75% of lymphocytes,62.5% of cholangiocytes, 37.5% of hepatocytes and50% of the sinusoidal cells with a much stronger staining intensity. No staining was observed when either normal or PBC sera were used as a primary antibody on liver sections from the disease control group. When PBC sera were incubated with healthy control sections,weak positive staining of cholangiocytes was observed in 3/21(14.3%) PBC serum samples. Steatohepatitis serum on PBC sections gave a positive staining of some hepatocytes and lymphocytes but no staining on viral hepatitis sections. Incubation with HBV sera stained some hepatocytes, cholangiocytes and intra-sinusoidal or portal lymphocytes of PBC, HBV and AAH patients but not HCV patients.CONCLUSION: In this study, for the first time in diseased liver tissue, we have demonstrated that a large proportion of PBC patients have disease specific autoantibodies against liver sinusoidal cells.

Cathepsin D: Autoantibody profiling as a diagnostic marker for cancers

Current diagnostic assays for many cancers are antigen-based and rely on the detection of circulating proteins that are associated with a particular cancer.These assays depend on the expression,synthesis,and release of specific proteins by cells(e.g.,tumor cells)through either active secretion or shedding,or as a consequence of cell death(either necrosis or apoptosis).As such,these antigenic proteins must“escape”the primary site of disease,saturate the antigen-processing capacity of the individual’s immune components,gain access to the circulation,and reach a sufficient steady-state concentration to be detected by enzyme-or radiolabel-based immunoassays.These events usually occur after the initial establishment of disease.Thus,and despite the fact that certain specific antigenic epitopes exhibit common recognition among patients with the same tumor types,the use of these antigen-based cancer assays has not been widely accepted in clinical practice,and many individual countries differ in the use of these potential diagnostic factors.Lately,an increasing number of studies demonstrated that procathepsin D secreted from cancer cells,acts as a mitogen on cancer cells and stimulates their pro-invasive and pro-metastatic properties.In this report,we focused on the possibility to use antiprocathepsin D autoantibodies as a diagnostic and/or predictive marker for cancers.

Autoantibodies against MMP-7 as a novel diagnostic biomarker in esophageal squamous cell carcinoma

AIM： To evaluate the diagnostic values of serum autoan tibodies against matrix metalloproteinase-7 （MMP-7） in patients with esophageal squamous cell carcinoma （ESCC）. METHODS： The MMP-7 cDNA was cloned from ESCC tissues, and MMP-7 was expressed and purified from a prokaryotic system. MMP-7 autoanUbodies were then measured in sera from 50 patients with primary ESCC and 58 risk-matched controls, using a reverse capture enzyme-linked immunosorbent assay （ELISA） in which autoantibodies to MMP-7 bound to the purified MMP-7 proteins. In addition, MMP-7 autoantibody levels in sera from 38 gastric cancer patients and from control serum samples were also tested. RESULTS： The optimum conditions for recombinant MMP-7 protein expression were determined as 0.04 mmol/L Isopropyl-13-D-Thiogalactopyranoside （IPTG）induction at 37℃ for four hours. The levels of serum autoantibodies against MMP-7 were significantly higher in patients with ESCC than in the matched-control samples （OD450 = 1.69 ±0.08 vs OD450 = 1.55 ± 0.10, P 〈 0.001）. The area under the receiver operating character- istic （ROC） curve was 0.87. The sensitivity and specificity for detection of ESCC were 78.0% and 81.0%, respectively, when the OD450 value was greater than 1.65. Although the levels of autoantibodies against MMP-7 were also significantly higher in patients with gastric cancer compared to control samples （OD450 = 1.62± 0.06 vs OD450 = 1.55±0.10, P 〈 0.001）, the diagnostic accuracy was less significant than in ESCC patients. The area of ROC curve was 0.75, whereas the sensitivity and specificity were 60.5% and 71.7%, respectively, when the cut-off value of OD450 was set at 1.60. CONCLUSION： Serum autoantibody levels of MMP-7 may be a good diagnostic biomarker for esophageal squamous cell carcinoma,