Autoantibodies In Sera Of Patients Research Articles

Detection of tumor-specific autoantibodies in sera of patients with lung cancer

The presence of autoantibodies (AAs) in sera from two pulmonary carcinoma patients, adenocarcinoma (AD) and small cell carcinoma (SCLC) was screened by immunoblotting using cell lysate of four cell lines (LCN1, large cell neuroendocrine carcinoma (LCNEC); N231, SCLC; A549, AD; RERF-LC-AI, squamous cell carcinoma (SCC)). To identify the antigens recognized by AAs, two-dimensional gel electrophoresis was immunoblotted and target spots were cut out from the membrane and gel. After trypsin digestion, the proteins were analyzed by mass-spectrometry using a liquid chromatography-tandem mass spectrometer. By this method, cytokeratin18 (CK18) and villin1 were identified with AAs in sera from patients with AD and SCLC, respectively. Thus, the expressions of CK18 and villin1 were further immunohistochemically studied on 124 formalin-fixed and paraffin-embedded pulmonary carcinomas of various histologic types (44 AD, 27 SCC, 29 SCLC, and 34 LCNEC) using commercially available CK18 and villin1 antibodies. Positive CK18 immunostaining was observed in almost all cases with staining intensities significantly higher in AD and LCNEC than in SCC and SCLC. Villin1 was detected in 17/44 (38.6%) of AD and 21/34 (61.8%) of LCNEC, respectively, while in only one each of SCLC and SCC. Thus, villin1 and CK18 may be useful markers to distinguish LCNEC/AD from SCLC/SCC, and the present method might be useful to identify specific tumor-associated molecules in sera from pulmonary carcinoma patients with different histologic types.

Automatic Analysis of Immunofluorescence Patterns of HEp‐2 Cells

The standard screening test for the recognition of autoimmune diseases is the proof of autoantibodies in serum of patients by indirect immunofluorescence (IIF) based on HEp-2 cells. Manual evaluation of this test is very subjective, slow, and there are no objective parameters as guidelines available. Interlaboratory tests showed occasionally large deviations in the test evaluation resulting in a high variance of results. The aim of this project is fast, objective, safe, and economical automatic analysis of HEp-2 IIF patterns. Images of IIF patterns were completely and automatically captured using an inverse motorized fluorescence microscope. Thereby, device-specific parameters were controlled automatically, too. For fast analysis of IIF patterns new algorithms of image processing were developed. Artifacts were recognized and excluded from analysis by the developed software. Analysis of more than 80,000 images clearly demonstrated full automatization and fast processing of IIF patterns. Additionally serum-specific fluorescence could be easily distinguished from background. Even very weak but positive patterns can be recognized and used for diagnosis. A detailed separation into different basic patterns is possible. Objective, fast, and disease-related economical analysis of HEp-2 immunofluorescence patterns is feasible. The implemented software algorithms allowed a mathematical way of describing IIF patterns and can therefore be a useful tool for the needed standardization process.

A New Target for Autoantibodies in Patients with Rheumatoid Arthritis

Early treatment of rheumatoid arthritis (RA) with disease-modifying antirheumatic drugs can achieve a better disease outcome and reduce the severity of joint damage. The presence of autoantibodies in patient sera can precede onset of the disease and thus be predictive of the development of RA. To date, known autoantibodies in RA are positive in only 50-60% of RA patients at onset of disease and even less before the onset of any RA symptom. The aim of this study was to identify new antibodies that could be useful for the diagnosis of RA using synovial membrane proteins, which represent the best source of candidate RA autoantigens. The humoral reactivity of sera from RA patients was explored using immunoblotting on extracted proteins obtained from synovial membranes from RA after synovectomy or arthroplasty. A new target protein with a molecular weight of 26 kDa was found to be recognized by autoantibodies in RA sera. This protein was identified using MALDI-TOF mass spectrometry and two-dimensional electrophoresis as carbonic anhydrase III with a high level of confidence. In conclusion, this study demonstrates new autoantibodies in RA patients that are directed against carbonic anhydrase III. The sensitivity and specificity of these new autoantibodies for RA have to be further evaluated.

Presence of autoantibodies in sera of patients with sporadic idiopathic hypoparathyroidism

目的 探讨散发性特发甲状旁腺机能减退症患者体内是否存在自身免疫性抗体.方法 对散发性特发甲状旁腺机能减退症患者26例、其直系亲属112例以及健康对照者60例,采用间接免疫荧光技术检测抗甲状旁腺自身免疫性抗体,同时检测血清钙、磷、镁、甲状旁腺激素含量.结果 散发性特发甲状旁腺机能减退症患者血清中抗甲状旁腺自身抗体阳性10例,阳性率为38%,明显高于直系亲属的10%(χ2=13.42,P＜0.01)和健康对照者的7%(χ2=13.46,P＜0.01).患者以女性为主(19/26),抗体阴性患者平均病程0.5～7年(中位数为2.2年),较抗体阳性患者平均病程0.5～4.5年(中位数为1.75)有延长的趋势;血清甲状旁腺激素水平在抗体阴性患者中为(7.06±2.06)ng/L,较抗体阳性患者的(8.86±2.86)ng/L有降低的趋势,差异无统计学意义(P=0.74).结论 散发性特发甲状旁腺机能减退症患者体内有抗甲状旁腺的自身免疫性血清学证据,抗甲状旁腺抗体的出现提示该病与自身免疫有关。

Measurement of gp210 autoantibodies in sera of patients with primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune liver disease with unknown etiology. Patients with PBC have antimitochondrial autoantibodies (AMA) and additionally 50% of them have antinuclear antibodies (ANA). A 15-amino acid fragment (DRKASPPSGLWSPAY) from the C-terminal part of the nuclear envelope glycoprotein gp210 has been proposed as one of the antigenic targets for ANA. The aim of this work was to develop an immunoenzymatic assay for determination of gp210 autoantibodies using for its binding a synthetic pentadecapeptide derived from the gp210 amino acid sequence and to determine level of these autoantibodies in sera of patients with PBC and other autoimmune liver diseases from Poland. Polystyrene microtitration plates coated with the synthetic peptide were consecutively incubated with diluted sera, anti-human immunoglobulin G (IgG) antibodies conjugated with horseradish peroxidase, and with tetramethylobenzidine. Optical density (OD) was read at 450 nm. The mean values of the intra- and interassay of variation coefficients of the test were 4.1 and 10.2%, respectively. Anti-gp210 was detected in 44% of PBC patients and in 6% of patients with PSC. The results were negative for healthy blood donors and other controls. The specificity of the test was 99%, so the anti-gp-210 autoantibodies estimated on DRKASPPSGLWSPAY can be a reliable marker of PBC.

Antibodies targeting the calcium binding skeletal muscle protein calsequestrin are specific markers of ophthalmopathy and sensitive indicators of ocular myopathy in patients with Graves' disease.

We have identified several eye muscle antigens and studied the significance of the corresponding serum autoantibodies in patients with Graves' disease. Of these antigens, only calsequestrin is expressed more in eye muscle than other skeletal muscles, which could explain at least partly the specific involvement of eye muscle in patients with Graves' disease. Earlier, we found a modest relationship between anti-calsequestrin antibodies and ophthalmopathy, but in that study we used calsequestrin prepared from rabbit heart muscle and measured antibodies by immunoblotting. We have reinvestigated the prevalences of anti-calsequestrin antibodies in larger groups of well-characterized patients with thyroid autoimmunity with and without ophthalmopathy and control patients and healthy subjects, using standard enzyme-linked immunosorbent assay incorporating highly purified rabbit skeletal muscle calsequestrin, which has a 97% homology with human calsequestrin, as antigen. Anti-calsequestrin antibodies were detected in 78% of patients with active congestive ophthalmopathy, in 92% of those with active inflammation and eye muscle involvement, but in only 22% of patients with chronic, 'burnt out' disease. Tests were also positive in 5% of patients with Graves' hyperthyroidism without evident ophthalmopathy (two patients) and one patient with 'watery eyes' but no other clear signs of congestive ophthalmopathy and IgA nephropathy and no known thyroid disease, but in no patient with Hashimoto's thyroiditis, toxic nodular goitre, non-toxic multi-nodular goitre or diabetes, or age- and sex-matched healthy subjects. In serial studies of all 11 patients with Graves' hyperthyroidism who had active ophthalmopathy at the time of the first clinic visit, or developed eye signs during the first 6 months, and positive anti-calsequestrin antibodies in at least one sample, anti-calsequestrin antibodies correlated with the onset of ocular myopathy in six patients. Antibodies targeting calsequestrin appear to be specific markers for ophthalmopathy and sensitive indicators of the ocular myopathy subtype of ophthalmopathy in patients with thyroid autoimmunity. However, these results must be considered preliminary until a large prospective study of patients with newly diagnosed Graves' hyperthyroidism, in which serum levels of calsequestrin antibodies are correlated with clinical changes and orbital eye muscle and connective tissue/fat volumes, has been carried out.

Serum autoantibodies of patients with chronic hepatitis C and the significance thereof in infection of hepatitis C virus

To investigate the serum autoantibodies in patients with chronic hepatitis C and to investigate the significance of autoimmune reaction in hepatitis C virus (HCV) infected patients. Peripheral blood samples were collected from 69 patients with chronic hepatitis C, 69 patients with chronic hepatitis B (HB), and 69 patients with autoimmune hepatitis (AIH). Indirect immunofluorescence technique was used to detect the serum anti nuclear antibody (ANA), anti-mitochondrial antibody (AMA), anti-smooth muscle antibody (anti-SMA), and anti-liver-kidney antibody (anti-LKM). HCV RNA was detected by PCR. The biochemical indices: alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and gamma-globulin were detected. The relations of autoantibodies to virus load, HCV genotype, cirrhosis, age, sex, and liver function were analyzed. (1) Twenty of the HCV patients were positive in autoantibodies, most being at a low titer, 11 of them being positive in ANA, 7 in anti-SMA, 1 in anti-AMA, and 1 in anti-LKM, with a positive rate of 28.9%, significantly higher than that of the HB patients (4.3%, P < 0.05), and significantly lower than that of the AIH patients (100%, P < 0.05). (2) There were no significant differences between the autoantibody positive group and autoantibody negative group in virus load and HCV genotype. (3) Fourteen of the 18 patients positive in autoantibodies responded to the anti-virus treatment with alpha-interferon with a response rate of 77.8%, significantly higher than that of the autoantibody negative group (53%, P < 0.05). (4) The average age of the autoantibody positive group was 47 +/- 18 years, significantly higher than that of the autoantibody negative group (39 +/- 12 years, P < 0.05). The positive autoantibody rate of the patients aged >or= 40 was 23.1%, significantly higher than that of the patients aged < 40 (5.8%, P < 0.05). There was no significant difference in the autoantibody rate between males and females. (5) The cirrhosis prevalence rate of the autoantibody positive group was 80%, significantly higher than that of the autoantibody negative group (46.9%, P < 0.05). (6) The serum ALT, AST, TBIL and gamma-globulin of the autoantibody positive group were 191 U/L +/- 89 U/L, 169 U/L +/- 80 U/L, 78 micromol/L +/- 50 micromol/L, and 200 g/L +/- 80 g/L respectively, all significantly higher than those of the autoantibody negative group (113 U/L +/- 69 U/L, 98 U/L +/- 62 U/L, 51 micromol/L +/- 30 micromol/L, and 160 g/L +/- 70 g/L respectively, all P < 0.05). (7) There were no significant differences in HCV RNA load and HCV genotype between the autoantibody positive group and the autoantibody negative group (both P > 0.05). HCV infection induces the autoimmune reaction resulting in production of autoantibodies. Positive autoantibody rate is related with cirrhosis and age. Titer and type of autoantibody serve as important indices in the diagnosis and treatment of HCV.

Phosphorylated and nonphosphorylated epitopes of the La/SSB autoantigen: Comparison of their antigenic and conformational characteristics

La/SSB phosphoprotein is the target antigen of autoantibodies in sera of patients with Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE). Among other structural and function motifs, four phosphorylation sites are encompassed in the primary sequence of La/SSB. Two of them (Thr-362 and Ser-366) are located within GSGKGKVQFQGKKTKFASDD (346-368) and one (Thr-302) within VTWEVLEGEVEKEALKKI (301-318), which are main B-cell epitopes of La/SSB. With the aim to investigate how phosphorylation, one of the most common posttranslational protein modifications, affects the antigenic and conformational characteristics of the La/SSB epitopes, we synthesized and studied the phosphorylated epitopes La/SSB(346-368)-P, La/SSB(359-368)-P, and La/SSB(301-318)-P with respect to their nonphosphorylated counterparts. Anti-La/SSB positive sera from SS and SLE patients are better recognized by the phosphorylated epitopes compared to their nonphosphorylated counterparts. Conformational analysis by (1)H nuclear magnetic resonance spectroscopy and molecular dynamics showed that the phosphorylated epitopes adopt different structural characteristics from those of the corresponding nonphosphorylated epitopes. It is concluded that phosphorylation can create neoepitopes with altered functions, compared to the nonphosphorylated epitopes, which might be seen from the immune system as "foreign."

Identification and characterization of the carboxy-terminal region of Sip-1, a novel autoantigen in Behçet's disease

Given the lack of a serological test specific for Behçet's disease, its diagnosis rests upon clinical criteria. The clinical diagnosis is nevertheless difficult because the disease manifestations vary widely, especially at the onset of disease. The aim of this study was to identify molecules specifically recognized by serum autoantibodies in patients with Behçet's disease and to evaluate their diagnostic value. We screened a cDNA library from human microvascular endothelial cells with serum IgG from two patients with Behçet's disease and isolated a reactive clone specific to the carboxy-terminal subunit of Sip1 (Sip1 C-ter). Using ELISA, we measured IgG, IgM and IgA specific to Sip1 C-ter in patients with various autoimmune diseases characterized by the presence of serum anti-endothelial cell antibodies, such as Behçet's disease, systemic lupus erythematosus, systemic sclerosis and various forms of primary vasculitis, as well as in patients with diseases that share clinical features with Behçet's disease, such as inflammatory bowel disease and uveitis. IgM immunoreactivity to Sip1 C-ter was significantly higher in patients with Behçet's disease and in patients with primary vasculitis than in the other groups of patients and healthy subjects tested (P < 10-4 by Mann-Whitney test). ELISA detected IgG specific to Sip1 C-ter in sera from 11/56 (20%) patients with Behçet's disease, IgM in 23/56 (41%) and IgA in 9/54 (17%). No sera from patients with systemic lupus erythematosus, systemic sclerosis, inflammatory bowel disease, uveitis or healthy subjects but 45% of sera from patients with primary vasculitis contained IgM specific to Sip1 C-ter. Serum levels of soluble E-selectin, a marker of endothelial activation and inflammation, correlated with levels of serum IgM anti Sip-1 C-ter in patients with Behçet's disease (r = 0.36, P = 0.023). In conclusion, Sip1 C-ter is a novel autoantigen in Behçet's disease. IgM specific to Sip1 C-ter might be useful in clinical practice as an immunological marker of endothelial dysfunction in vasculitis.

Enzyme-linked immunosorbent assay for detection of peptide-specific human antidesmoplakin autoantibodies

Autoantibodies directed against desmoplakin (Dp) I and II have recently been characterized in a subset of patients with severe erythema multiforme (EM), a recurrent inflammatory skin disease with a broad spectrum of clinical manifestations. These autoantibodies recognize a peptide epitope localized within the extreme end of the carboxy terminal domain of Dp responsible for the assembly of keratin filaments to the desmosomal plaque. Using dot blot analysis with overlapping synthetic peptides, the binding epitope YSYSYS has been identified. To establish an enzyme-linked immunosorbent assay (ELISA) for detection of peptide-specific anti-Dp autoantibodies in sera of patients with EM. A synthetic peptide containing the respective amino acid sequence was used as matrix for ELISA plates. Serum samples from patients with known EM and peptide-specific anti-Dp autoantibodies verified by immunoblotting, immunoprecipitation and epitope mapping were used. Establishing an index value of 42.0, 25 of 25 serum samples from five patients with peptide-specific anti-Dp autoantibodies were positive in the ELISA. From control sera, none of 31 bullous disease sera and only one (1.2%) of 83 normal human sera were positive. These data show that the ELISA presented in this study represents a sensitive and highly specific tool for the detection of peptide-specific anti-Dp autoantibodies in patients with EM.

Immune responses to Campylobacter and serum autoantibodies in patients with complex regional pain syndrome

We hypothesised that some complex regional pain syndromes (CRPS) may have a postinfectious and/or autoimmune basis. Sera from 92 patients with CRPS and 92 controls were investigated for immunoreactivity to Campylobacter strains and to rodent tissues. Both IgA-antibodies to Campylobacter and tissue-specific reactivity were often present in patients with short disease duration (≤1.5 years). Patients with minimal preceding trauma had stronger nervous tissue-specific reactivity than other patients, regardless of disease duration. These results provide preliminary evidence for immune activation early in CRPS and, additionally, that patients with minimal trauma may comprise an autoimmune subgroup.

The presence of anti-mitochondrial autoantibodies in sera of patients with autoimmune hepatitis - it is relatively common but not contributive to biliary changes: Saeko Yajima, Third Dept of Internal Medicine, Kyorin Univ, Tokyo Japan; Atsushi Tanaka, Inst for Adult Diseases, Asahi Life Fdn, Tokyo Japan; Makiko Imamura, Hiroshi Nakajima, Hitoshi Ishida, Shin-Ichi Takahashi, Third Dept of Internal Medicine, Kyorin Univ,

The presence of anti-mitochondrial autoantibodies in sera of patients with autoimmune hepatitis - it is relatively common but not contributive to biliary changes: Saeko Yajima, Third Dept of Internal Medicine, Kyorin Univ, Tokyo Japan; Atsushi Tanaka, Inst for Adult Diseases, Asahi Life Fdn, Tokyo Japan; Makiko Imamura, Hiroshi Nakajima, Hitoshi Ishida, Shin-Ichi Takahashi, Third Dept of Internal Medicine, Kyorin Univ,

Autoantibodies in systemic sclerosis and fibrosing syndromes: clinical indications and relevance

Systemic sclerosis, or scleroderma, is associated with a variety of autoantibodies, each of them having their own clinical associations. The fibrosing disorders, other than systemic sclerosis, represent a diverse group of diseases with systemic or localized effect and with limited understanding of their pathogenesis. The purpose of this review is to analyze the literature on the clinical usefulness of examining serum autoantibodies in patients with known or suspected scleroderma and fibrosing disorders. Studies on autoantibodies within the past year highlight their clinical utility in systemic sclerosis. Anticentromere antibodies are most often seen with limited cutaneous involvement and lower frequency of pulmonary fibrosis and lower mortality (despite an increased risk for pulmonary hypertension) compared with anti-Scl-70 and antinucleolar antibodies. Anti-Scl-70 antibodies are associated with diffuse cutaneous involvement, increased frequency of pulmonary fibrosis, and higher mortality. The anti-polymyositis-scleroderma autoantibody is associated with the polymyositis-scleroderma overlap syndrome. Anti-Th/To antibodies are associated with milder skin and systemic involvement but with more severe pulmonary fibrosis and overall worse prognosis. Anti-RNA-polymerase family antibodies and antifibrillarin antibodies are predictive of diffuse cutaneous and systemic involvement and greater mortality. Less specific autoantibodies for systemic sclerosis and limited data on some other autoantibodies limit their clinical utility in patients with systemic sclerosis. For the most part, the association between autoantibodies and fibrosing disorders other than systemic sclerosis remains inconclusive. Autoantibodies in systemic sclerosis provide important and prognostic information and are useful in defining clinical subsets of the disease. When used appropriately, they can be a useful instrument in the management of scleroderma.

Chronic urticaria: Expanding the autoimmune kaleidoscope

Chronic urticaria: Expanding the autoimmune kaleidoscope

Autoantibodies from primary biliary cirrhosis patients with anti-p95c antibodies bind to recombinant p97/VCP and inhibit in vitro nuclear envelope assembly.

We have reported previously that p95c, a novel 95-kDa cytosolic protein, was the target of autoantibodies in sera of patients with autoimmune hepatic diseases. We studied 30 sera that were shown previously to immunoprecipitate a 95 kDa protein from [(35)S]-methionine-labelled HeLa lysates and had a specific precipitin band in immunodiffusion. Thirteen sera were available to test the ability of p95c antibodies to inhibit nuclear envelope assembly in an in vitro assay in which confocal fluorescence microscopy was also used to identify the stages at which nuclear assembly was inhibited. The percentage inhibition of nuclear envelope assembly of the 13 sera ranged from 7% to 99% and nuclear envelope assembly and the swelling of nucleus was inhibited at several stages. The percentage inhibition of nuclear assembly was correlated with the titre of anti-p95c as determined by immunodiffusion. To confirm the identity of this autoantigen, we used a full-length cDNA of the p97/valosin-containing protein (VCP) to produce a radiolabelled recombinant protein that was then used in an immunoprecipitation (IP) assay. Our study demonstrated that 12 of the 13 (93%) human sera with antibodies to p95c immunoprecipitated recombinant p97/VCP. Because p95c and p97 have similar molecular masses and cell localization, and because the majority of sera bind recombinant p97/VCP and anti-p95c antibodies inhibit nuclear assembly, this is compelling evidence that p95c and p97/VCP are identical.

Expansion of CD5 - B cells in multiple sclerosis correlates with CD80 (B7-1) expression.

The pathogenetic role of autoantibodies in multiple sclerosis (MS) is uncertain. CD5+ B cells commonly produce autoantibodies, but CD5 expression has also been implicated in B-cell tolerance. We studied B-cell subsets, anti-myelin protein antibody-secreting cells in cerebrospinal fluid (CSF) and a panel of serum autoantibodies in patients with clinically isolated syndromes (CIS), suggestive of MS and patients with clinically definite MS (CDMS). Patients with CDMS had a higher percentage of CD5- B cells in CSF than did control subjects (P = 0.02). CIS patients with immunoglobulin G (IgG) oligoclonal bands in CSF or multiple lesions on magnetic resonance imaging (MRI) had a higher percentage of CD5- B cells in CSF than did the remaining CIS patients (P = 0.03). The percentage of CD5- and CD80+ B cells correlated positively and the percentage of CD5+ B cells correlated negatively with the number of CSF cells secreting anti-myelin basic protein (anti-MBP) antibodies. The prevalence of serum autoantibodies was comparable in the three patient groups. We conclude that intrathecal expansion of CD5- B cells appears to be more characteristic in MS patients, and CD5+ B cells may be associated with a lower prevalence of anti-myelin antibody production.

Relationship of myocardial remodeling to the genesis of serum autoantibodies to cardiac beta1-adrenoceptors and muscarinic type 2 acetylcholine receptors in rats

ObjectivesWe sought to investigate the mechanism responsible for the occurrence of anticardiac receptor autoantibodies. BackgroundIncreasing evidence suggests the involvement of autoimmune mechanisms in the pathogenesis of a number of cardiovascular diseases. Among them, the biologic, functional and pathogenic properties of anticardiac receptor antibodies have been extensively investigated. However, the mechanism responsible for the occurrence of anticardiac receptor autoantibodies remains poorly understood. MethodsTwo rat models (aortic banding [AB] and adriamycin [ADR] groups) were constructed. Determination of cardiac function and morphology and T-lymphocyte subtypes, enzyme-linked immunosorbent assay and cardiomyocyte cultures were performed. ResultsIt was shown, in the AB and ADR groups, that the frequency and titer of autoantibodies to beta1and muscarinic type 2 receptors were increased when myocardial remodeling occurred, as evidenced by significant cardiac morphologic changes, deposition of collagen and obvious functional impairment. This suggests that cardiac remodeling itself, in two disparate models of heart failure and cardiomyopathy, was able to trigger the genesis of anticardiac receptor autoantibodies. These autoantibodies have biologic effects similar to those seen in human autoantibodies. They have also shown a characteristic self-growth, as well as a time-course decline, suggesting that a negative finding of anticardiac receptor autoantibodies in sera of patients with heart disease does not necessarily imply that there is no autoimmune reaction involved in the pathogenesis. ConclusionsOur results demonstrated that myocardial damage was able to trigger the occurrence of an autoimmune reaction, resulting in the genesis of anticardiac receptor autoantibodies with properties similar to those seen in patients with idiopathic dilated cardiomyopathy.

Pituitary Autoantibodies in Lymphocytic Hypophysitis Target Both γ- and a-Enolase – A Link with Pregnancy?

The first target autoantigen to have been identified in lymphocytic hypophysitis is a 49 kDa protein, identified as alpha-enolase. Pituitary autoimmunity is strongly associated with pregnancy and we have shown that pituitary autoantibodies from patients with peripartum lymphocytic hypophysitis also recognise enolase in the placenta. Enolase exists in different forms as a number of isoenzymes, which are homo- or heterodimers of three subunits, α, β and γ. aa-enolase is ubiquitous, ββ-enolase is muscle-specific and γγ-enolase, which is restricted to neuronal tissue and neuroendocrine cells, is known as neuron-specific enolase (NSE). NSE is expressed in normal human pituitary and pituitary neoplasms. The current study investigated which isoforms of enolase in pituitary and placenta reacted with the sera of patients with lymphocytic hypophysitis. Immunoblotting of two-dimensional gels of human pituitary cytosolic proteins showed that autoantibodies in patient sera react with both an acidic form, and more neutral forms of enolase. Immunoblotting with a monoclonal antibody to NSE confirmed the identity of the acidic enolase isoform as the γγ-isoform in both pituitary and placental samples. Gamma-enolase, i.e. NSE, was detected by immunohistochemistry in term placenta in decidua, syncytiotrophoblasts, anchoring villi and terminal villi. Our study is the first to describe the cellular localisation of NSE in normal human placenta, thus establishing a direct link between pituitary and placental autoantigens. This link provides a theoretical basis for the strong prediliction of lymphocytic hypophysitis to occur during or after pregnancy.

Low prevalence of liver-kidney microsomal autoantibodies of type 1 (LKM1) in hepatitis C seropositive subjects on Crete, Greece.

BackgroundHepatitis C is a serious problem on the Greek island of Crete, where a high prevalence of antibodies against hepatitis C (anti-HCV) has recently been reported. This article reports the findings of a study carried out in Crete, which investigated the prevalence of serum autoantibodies in patients with chronic hepatitis C.Patients and MethodsOne hundred and forty two patients (59 men and 83 women), who were found anti-HCV seropositive in two hospitals and two Primary Health Care Centres in Crete, were eligible. Sixty healthy blood donors (46 men, 14 women), which were negative to anti-HCV, were used as the control group. They were randomly selected from those attending Rethymnon Hospital. Autoantibodies were identified using the indirect immunofluorescence (IFL) technique on human epithelial cells from larynx cancer (HEp-2 cells), rat liver-kidney-stomach substrate (CT3) and Chrithidia Luciliae (CL).ResultsSerum autoantibodies were detected in 104 HCV patients, yielding an overall prevalence of 73.2%. The most frequent autoantibodies were antinuclear antibodies (ANA), positive in 72 patients (50.7%). Anti-smooth muscle antibodies (ASMA) were detected in 33 patients (23.2%). Only one patient was positive for LKM1 autoantibodies. No autoantibodies were found in 38 patients (26.7%). Autoantibodies were also found in 5 out of the 60 examined healthy blood donors (8.3%).ConclusionsAutoantibodies, mainly ANA and ASMA are very common in HCV seropositive patients from Crete. By contrast LKM1 autoantibodies are exceptionally rare in these patients.

More panantigens in Leishmania

Response from Requena et al.The proteasome is a multi-subunit, cylinder-shaped structure that constitutes a molecular machine specialized in intracellular protein degradation 1xThe 26S proteasome: a molecular machine designed for controlled proteolysis. Voges, D et al. Annu. Rev. Biochem. 1999; 68: 1015–1068Crossref | PubMed | Scopus (1310)See all