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.

Role of biochemical markers and autoantibodies in diagnosis of early-stage primary biliary cholangitis

BACKGROUND Primary biliary cholangitis(PBC)is a chronic progressive autoimmune cholestatic disease.The main target organ of PBC is the liver,and nonsuppurative inflammation of the small intrahepatic bile ducts may eventually develop into cirrhosis or liver fibrosis.AIM To explore the clinical characteristics of early-stage PBC,identify PBC in the early clinical stage,and promptly treat and monitor PBC.METHODS The data of 82 patients with PBC confirmed by pathology at Tianjin Second People’s Hospital from January 2013 to November 2021 were collected,and the patients were divided into stage I,stage II,stage III,and stage IV according to the pathological stage.The general data,serum biochemistry,immunoglobulins,and autoimmune antibodies of patients in each stage were retrospectively analyzed.RESULTS In early-stage(stages I+II)PBC patients,50.0%of patients had normal alanine aminotransferase(ALT)levels,and 37.5%had normal aspartate aminotransferase(AST)levels.For the remaining patients,the ALT and AST levels were mildly elevated;all of these patients had levels of<3 times the upper limit of normal values.The AST levels were significantly different among the three groups(stages I+II vs stage III vs stage IV,P<0.05).In the early stage,29.2%of patients had normal alkaline phosphatase(ALP)levels.The remaining patients had different degrees of ALP elevation;6.3%had ALP levels>5 times the upper limit of normal value.Moreover,γ-glutamyl transferase(GGT)was more robustly elevated,as 29.2%of patients had GGT levels of>10 times the upper limit of normal value.The ALP values among the three groups were significantly different(P<0.05).In early stage,the jaundice index did not increase significantly,but it gradually increased with disease progression.However,the above indicators were significantly different(P<0.05)between the early-stage group and the stage IV group.With the progression of the disease,the levels of albumin and albumin/globulin ratio tended to decrease,and the difference among the three groups was statistically significant(P<0.05).In early-stage patients,IgM and IgG levels as well as cholesterol levels were mildly elevated,but there were no significant differences among the three groups.Triglyceride levels were normal in the early-stage group,and the differences among the three groups were statistically significant(P<0.05).The early detection rates of anti-mitochondria antibody(AMA)and AMA-M2 were 66.7%and 45.8%,respectively.The positive rate of anti-sp100 antibodies was significantly higher in patients with stage IV PBC.When AMA and AMA-M2 were negative,in the early stage,the highest autoantibody was anti-nuclear antibody(ANA)(92.3%),and in all ANA patterns,the highest was ANA centromere(38.5%).CONCLUSION In early-stage PBC patients,ALT and AST levels are normal or mildly elevated,GGT and ALP levels are not elevated in parallel,GGT levels are more robustly elevated,and ALP levels are normal in some patients.When AMA and AMA-M2 are negative,ANA especially ANA centromere positivity suggests the possibility of early PBC.Therefore,in the clinic,significantly elevated GGT levels with or without normal ALP levels and with ANA(particularly ANA centromere)positivity(when AMA and AMA-M2 are negative)may indicate the possibility of early PBC.

Intracranial infection accompanied sweet’s syndrome in a patient with anti-interferon-γautoantibodies:A case report

BACKGROUND Several reports of adult-onset immunodeficiency syndrome have been associated with anti-interferon-gamma(IFN-γ)autoantibodies(AIGAs).However,it is rare to find AIGAs with intracranial infections.CASE SUMMARY In this case study,we report a case of an AIGAs with intracranial infection and hand rashes considered Sweet’s syndrome.The patient presented to our hospital with a persistent cough,a fever that had been going on for 6 mo,and a rash that had been going on for a week.The patient started losing consciousness gradually on the fourth day after admission,with neck stiffness and weakened limb muscles.The upper lobe of the left lung had a high-density mass with no atypia and a few inflammatory cells in the interstitium.Brain magnetic resonance imaging and cerebrospinal fluid suggest intracranial infection.The pathology of the skin damage on the right upper extremity revealed an infectious lesion that was susceptible to Sweet’s disease.It has an anti-IFN-γautoantibody titer of 1:2500.She was given empirical anti-non-tuberculous mycobacterial and antifungal treatments.The patient had no fever,obvious cough,headache,or rash on the hand.She got out of bed and took care of herself following hospitalization and discharge with medicine.CONCLUSION Adults with severe and recurrent infections of several organs should be considered for AIGAs if no other known risk factors exist.AIGAs are susceptible to subsequent intracranial infections and Sweet’s syndrome.

Location-based prediction model for Crohn’s disease regarding a novel serological marker,anti-chitinase 3-like 1 autoantibodies

BACKGROUND Defective neutrophil regulation in inflammatory bowel disease(IBD)is thought to play an important role in the onset or manifestation of IBD,as it could lead to damage of the intestinal mucosal barrier by the infiltration of neutrophils in the inflamed mucosa and the accumulation of pathogens.Like neutrophils in the context of innate immune responses,immunoglobulin A(IgA)as an acquired immune response partakes in the defense of the intestinal epithelium.Under normal conditions,IgA contributes to the elimination of microbes,but in connection with the loss of tolerance to chitinase 3-like 1(CHI3L1)in IBD,IgA could participate in CHI3L1-mediated improved adhesion and invasion of potentially pathogenic microorganisms.The tolerance brake to CHI3L1 and the occurrence of IgA autoantibodies to this particular target,the exact role and underlying mechanisms of CHI3L1 in the pathogenesis of IBD are still unclear.AIM To determine the predictive potential of Ig subtypes of a novel serological marker,anti-CHI3L1 autoantibodies(aCHI3L1)in determining the disease phenotype,therapeutic strategy and long-term disease course in a prospective referral cohort of adult IBD patients.METHODS Sera of 257 Crohn’s disease(CD)and 180 ulcerative colitis(UC)patients from a tertiary IBD referral center of Hungary(Division of Gastroenterology,Department of Internal Medicine,Faculty of Medicine,University of Debrecen)were assayed for IgG,IgA,and secretory IgA(sIgA)type aCHI3L1 by enzyme-linked immunosorbent assay using recombinant CHI3L1,along with 86 healthy controls(HCONT).RESULTS The IgA type was more prevalent in CD than in UC(29.2%vs 11.1%)or HCONT(2.83%;P<0.0001 for both).However,sIgA subtype aCHI3L1 positivity was higher in both CD and UC patients than in HCONT(39.3%and 32.8%vs 4.65%,respectively;P<0.0001).The presence of both IgA and sIgA aCHI3L1 antibodies was associated with colonic involvement(P<0.0001 and P=0.038,respectively)in patients with CD.Complicated disease behavior at sample procurement was associated with aCHI3L1 sIgA positivity(57.1%vs 36.0%,P=0.009).IgA type aCH3L1 was more prevalent in patients with frequent relapse during the disease course in the CD group(46.9%vs 25.7%,P=0.005).In a group of patients with concomitant presence of pure inflammatory luminal disease and colon involvement at the time of diagnosis,positivity for IgA or sIgA type aCH3L1 predicted faster progression towards a complicated disease course in time-dependent models.This association disappeared after merging subgroups of different disease locations.CONCLUSION CHI3L1 is a novel neutrophil autoantigenic target in IBD.The consideration of antibody classes along with location-based prediction may transform the future of serology in IBD.

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.

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.

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.

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.

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,

Development of an enzyme immune assay for detecting M2 autoantibodies specific for primary biliary cirrhosis

OBJECTIVE: To develope a new enzyme immune assay (ELISA) for detection of M2 antibody specific for primary biliary cirrhosis (PBC) by using a triple hybrid clone as antigen, which coexpresses the three immunodominant lipoyl domains of PDC-E2, BCOADC-E2 and OGDC-E2 from human sources. METHODS: After expressing autoantigens of PBC in prokaryote by constructing recombinant expressive plasmid successfully, the fusion protein was purified by affinity chromatography. The sera of 17 PBC patients were examined. As controls, the sera of 167 non-PBC patients and the sera of 1225 normal controls aged under 28 were examined. RESULTS: None of the sera from the non-PBC patients or the normal controls was positive for anti-M2 shown by the new ELISA. However, the positivity rate for anti-M2 in the PBC patients was 100% (17/17), as shown by the new ELISA. CONCLUSION: The detection system with a good sensitivity and specificity may be used as a powerful method for the diagnosis of PBC.

Autoantibodies in Alzheimer's disease:potential biomarkers,pathogenic roles,and therapeutic implications

Alzheimer＇s disease （AD） is a prevalent and debilitating neurodegenerative disorder in the elderly. The etiology of AD has not been fully defined and currently there is no cure for this devastating disease. Compelling evidence sug- gests that the immune system plays a critical role in the pathophysiology ofAD. Autoantibodies against a variety of molecules have been associated with AD. The roles of these autoantibodies in AD, however, are not well understood. This review attempts to summarize recent findings on these autoantibodies and explore their potential as diagnostic/ prognostic biomarkers for AD, their roles in the pathogenesis of AD, and their implications in the development of effective immunotherapies for AD.