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Y Shoenfeld

Publications and source records attributed to Y Shoenfeld.

At least 451 records · Page 25Linked to original sources

Autoantibody profile in the sera of women with hyperprolactinemia.

Prolactin (PRL) has been implicated as an important in vivo modulator of cellular and humoral immunity. In order to elucidate the impact of elevated serum PRL levels on the immune system, we measured circulating autoantibodies in the serum of 33 hyperprolactinemic (HPRL) women and in 19 healthy women with normal PRL levels. All sera were examined for the presence of autoantibodies against 15 different antigens, including: ssDNA, dsDNA, histones (H2AH2B), Sm, RNP, SS-A/Ro, SS-B/La, cardiolipin, Scl-70, Jo1, collagen, glomerular basement membrane (GBM), pyruvate dehydrogenase (PDH), proteinase-3 (PR3) and MPO. Twenty-five of 33 (75.7%) HPRL women were found to have at least one autoantibody, while none of the 19 women with normal PRL had any. Eight HPRL women had seven or more (up to nine) different autoantibodies. Some of the autoantibodies were more frequently expressed than others, namely: anti-ss-DNA, anti-dsDNA, anti-Sm, anti-PDH and anti-SS-A/Ro. Autoantibodies to the autoantigens tested are common in a variety of autoimmune and rheumatic disorders including systemic lupus erythematosus (SLE), Sjögren's syndrome, mixed connective tissue disease (MCTD), scleroderma, primary biliary cirrhosis (PBC), polymyositis/dermatomyositis and vasculitis. Yet none of the HPRL women whose serum was found to contain high titers of autoantibodies presented with symptoms related to the respective autoimmune disorders. Our results support the role of PRL in the regulation of immune responses in man.

Adult↗

Natural autoantibodies in sera of patients with Gaucher's disease.

Gaucher's disease (GD) is associated with hyperactivity of the immune system, which manifests by polyclonal hypergamma-globulinemia and an increased incidence of monoclonal gammopathies in GD patients. We analyzed sera of 43 patients with GD for the presence of autoantibodies against 14 autoantigens. The results demonstrated a significant increase in the incidence of all autoantibodies tested, ranging from 11% for anti-RNP, pyruvate dehydrogenase (PDH), and DNA antibodies to 57% for rheumatoid factor. The autoantibodies were of all three isotypes, namely, IgG, IgM, and IgA. There was no correlation between the levels of immunoglobulins in the serum and the titer of autoantibodies found. Immunization of naive mice with a pool of purified anti-DNA antibodies form GD patients did not result in induction of experimental systemic lupus erythematosus (SLE), suggesting that they may represent natural autoantibodies that are not pathogenic. In conclusion, we found high titers of natural, polyspecific, nonpathogenic autoantibodies in the sera of GD patients.

Adolescent↗

Pseudotumour cerebri in SLE.

A 29 year-old woman with SLE was admitted to our department due to severe remitting headaches. Following investigation a high degree of intra cranial pressure was determined. Several years ago a similar finding was diagnosed, and the disease was brought into remission by the administration of periodical pulses of high dose intravenous immunoglobulins. Benign intracranial hypertension (BIH) is an uncommon presentation of neuro-psychiatric SLE. In this patient several risk factors of BIH (obesity, steroid therapy, and SLE) assembled and elicited a severe presentation of the disorder which became more resistant to therapy. Several pathogenic pathways tie BIH with SLE as thrombotic obliteration of cerebral arteriolar and venous systems and immune complex deposition within the arachnoid villi (that are responsible for CSF absorption). As shown in this care report of BIH, clinical findings do not always parallel various imaging techniques as MRI and CT brain scans.

Adult↗

Identification and characterization of antimitochondrial autoantibodies in sera of patients with monoclonal gammopathies.

Monoclonal gammopathies (MG) are defined by the accumulation of monoclonal immunoglobulins, a result of monoclonal B lymphocytes or plasma cell proliferative disorder. Only rarely do these antibodies cause an overt disease by binding to a specific autoantigen (e.g., factor VIII). In the present study, sera from 100 patients with MG were screened for the presence of antibodies against the mitochondrial pyruvate dehydrogenase complex (PDH) -- autoantibodies that are the hallmark primary biliary cirrhosis (PBC). Anti-PDH antibodies were found in 6 patients, all asymptomatic. Using ELISA and immunoblotting methods, it was found that the titre of the anti-PDH antibodies was relatively low (average OD +/- SD: 0.744 +/- 0.529; PBC patients: 1.225 +/- 0.291; P = 0.02). In each patient the autoantibodies were of both kappa and lambda chains, suggesting that they are of polyclonal origin and implying that in MG there is a significant production of polyclonal autoantibodies, in addition to monoclonal proliferation. Furthermore, in 5 of the 6 patients (83%) the anti-PDH antibodies did not recognize the E2 component of PDH (which is the major autoantigen in PBC) an did not inhibit the activity of PDH (which was inhibited by PBC autoantibodies). This is in concert with the fact that none of the patients developed liver disease and emphasizes the specificity of the anti-PDH autoantibodies associated with PBC.

Antigen-Antibody Reactions↗

Anti-actin antibodies in sera from patients with autoimmune liver diseases and patients with carcinomas by ELISA.

UNLABELLED: Smooth muscle antibodies (SMA) were initially detected in sera of patients with chronic active hepatitis (CAH). Subsequently, their presence was demonstrated in a wide variety of other diseases. SMA are a mixture of antibodies directed towards different cytoskeletal antigens. Sera with high titers of anti-actin antibodies (AAA), a subgroup of SMA, are most frequently found among patients with autoimmune chronic active hepatitis (CAH) and, to a lesser extent, among patients with primary biliary cirrhosis (PBC) and other diseases. It is therefore established that AAA are a reliable marker to autoimmune CAH. The purpose of this study was to determine the titer of AAA in sera of patients with liver, autoimmune diseases and carcinomas, using the enzyme-linked immunoabsorbent assay (ELISA) method. The results were expressed as the optical density (OD) of the examined sera divided by the OD of a sera from a healthy control (presented as percentages +/- standard deviation). Sera of 33 patients with cirrhosis, nine patients with autoimmune CAH, fifteen patients with non-autoimmune CAH, eight patients with PBC, 30 patients with Sjogren's syndrome, 60 patients with SLE, 142 patients with carcinomas of different kinds, and 34 healthy donors were examined for the presence of AAA by ELISA. Statistically significant (P < 0.003) higher titers of AAA were detected in patients with autoimmune CAH (57 +/- 23%) compared with the control group and to other groups of diseases. AAA titers in non-autoimmune CAH were not significantly higher compared to the control group. High titers of AAA were detected in 67% of the patients with autoimmune CAH, as compared with other diseases in which only up to 13% of the patients exhibited AAA positivity. CONCLUSION: existence of higher levels of AAA noted in 67% of the patients with autoimmune CAH with regard to other groups of diseases, emphasizes the value of AAA as sensitive and specific markers, capable of characterizing the patients with autoimmune chronic active hepatitis.

Actins↗

The pathogenic human monoclonal anti-DNA that induces experimental systemic lupus erythematosus in mice is encoded by a VH4 gene segment.

Systemic lupus erythematosus (SLE) can be induced in mice by immunization with a human anti-DNA IgM mAb that was derived from a patient with cold agglutinin disease. The latter anti-DNA mAb expresses the common idiotype (Id) designated 16/6 Id. The original human hybridoma 16/6 that secreted an IgM antibody that bound ssDNA and carried the 16/6 Id had switched in culture to secrete an IgG molecule. Herein we show that the IgG 16/6 antibody contains the previously reported characteristics of the original IgM 16/6 mAb: it expresses the 16/6 Id and is capable of inducing experimental SLE in susceptible mouse strains. The identify of the IgG 16/6 anti-DNA mAb to the original IgM mAb was shown both by serological techniques and at the T cell level. The human IgG 16/6 mAb was found to be encoded by a germline gene from the human VH4 gene family, with high similarity to the germline gene VH4.21 that was previously shown to code for anti-DNA antibodies isolated from SLE patients. The VH4.21 germline gene was found to also code for most antibodies with cold agglutinin activity that were isolated from patients with cold agglutinin disease.

Amino Acid Sequence↗

Anti-tyrosinase antibodies participate in the immune response to vaccination with anti-idiotypic antibodies mimicking the high-molecular-weight melanoma-associated antigen.

Seven patients with metastatic melanoma were vaccinated with anti-idiotypic monoclonal antibody (mAb) MK2-23 which mimics the high-molecular-weight melanoma-associated antigen (HMW MAA). Sera samples were assayed for anti-anti-idiotypic antibodies, by Ab1-Ab2 complex inhibition test, for anti-B16 epitope antibodies, which are a heterogeneous group against various antigens presented on B16 melanoma cells and for anti-tyrosinase antibodies, which are specific against tyrosinase. Our results pointed to the participation of anti-tyrosinase antibodies in the immune response to vaccination by anti-idiotypic antibodies mimicking the HMW MAA. The anti-tyrosinase antibody kinetic curves presented an initial increase in titres in five cases followed by decreasing titres; in two cases a constant decrease was noted. The inhibition assay demonstrated an increasing percentage of inhibition (range 17-100%) within 100-400 days of treatment. The titre of the anti-tyrosinase antibodies increased following the vaccination, then decreased--probably due to absorption of the antibodies to melanoma cells and normal melanocytes. A positive slope in the percentage of inhibition was roughly associated with a negative slope of anti-tyrosinase antibodies. In one case, a long-standing complete clinical response was accompanied by development of melanoma-associated hypopigmentation. Anti-B16 epitope antibodies had no role in the response to vaccination. The development of anti-tyrosinase antibodies in response to vaccination by anti-idiotypic antibodies mimicking another antigen may be explained by induction of non-specific polyclonal B lymphocytes activation, a well-recognized phenomenon in autoimmune disorders.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Anti-Idiotypic↗

Early onset of autoimmunity in MRL/++ mice following immunization with beta 2 glycoprotein I.

Antiphospholipid antibodies (aPL) are associated with thrombosis, thrombocytopenia and recurrent fetal loss in humans and in some animal models. Immunization with beta 2 glycoprotein I (beta 2GPI) induced aPL production in normal rabbits and mice. However, the association of these antibodies with disease manifestations remains controversial. To determine whether induction of aPL by beta 2GPI immunization in an autoimmune strain of mice (MRL/++) would result in acceleration of clinical and serological autoimmune disease manifestations, three groups of 8-week-old female mice were studied. One group was immunized with beta 2GPI, and one with ovalbumin (OVA); the third was not immunized. After two booster injections, sera were analysed for the presence of anticardiolipin (aCL) and anti-DNA by ELISA and anti-nuclear antibody (ANA) by immunofluorescence. Mice were studied for thrombocytopenia, proteinuria, fecundity rates, litter sizes and the development of central nervous system dysfunction. Elevated levels of aCL, anti-DNA and ANA were detected in all beta 2GPI-immunized, in three OVA-immunized, and in none of the unimmunized mice. The anti-DNA antibodies were inhibited by CL micelles, suggesting cross-reactivity between aCL and anti-DNA. Platelet counts, fecundity rates and litter size were reduced in beta 2GPI-immunized but not in OVA-immunized or unimmunized mice. None of the mice developed neurological dysfunction or significant proteinuria over a 10-week period post-immunization. These findings suggest that beta 2GPI immunization induces aPL in MRL/++ mice associated with accelerated autoimmune manifestations resembling the antiphospholipid syndrome.

Animals↗

Immunization with anti-neutrophil cytoplasmic antibody (ANCA) induces the production of mouse ANCA and perivascular lymphocyte infiltration.

Wegener's granulomatosis (WG) is a granulomatous necrotizing vasculitis associated with the presence of ANCA, predominantly directed against proteinase 3 (PR3). The titres of ANCA correlate with disease activity and titre increases may precede disease exacerbations. Previously, we have shown that it is possible to induce autoimmune disease (systemic lupus erythematosus (SLE) and anti-phospholipid syndrome) in naive mice following active immunization with human autoantibodies, namely anti-DNA and anti-cardiolipin, respectively. The mice developed first anti-autoantibodies and, after about 4 months anti-anti-autoantibodies (Ab3), simulating auto-antibodies (Ab1) in their binding activities, and their presence was associated with the development of disease manifestations, characteristic of the human disease. So far, there is no good animal model for WG. In the current study we have immunized mice with human ANCA with the aim of inducing experimental WG. In two separate studies 30 mice were immunized in their footpads with autoantigen-purified IgG fraction (ANCA) from the sera of two patients with untreated WG, emulsified in Freund's complete adjuvant, followed 3 weeks later by ANCA injection in PBS. In the first experiment mice immunized with ANCA developed sterile microabscesses in the lungs after 8 months, and died after 8-15 months. In the second experiment, mice immunized with ANCA developed after 4 months mouse ANCA, with specificity both to PR3 and to myeloperoxidase, as well as anti-endothelial autoantibodies (AECA), as shown by radioimmunoprecipitation. Pathologically, the immunized mice developed proteinuria but not haematuria, and histological sections of the lungs demonstrated mononuclear perivascular infiltration, while diffuse granular deposition of immunoglobulins was noted in the kidneys. Our results point to a pathogenic role of ANCA in WG, and confirm the importance of the idiotypic network in the etiopathogenesis of autoimmune conditions.

Animals↗

Induction of tolerance to experimental anti-phospholipid syndrome (APS) by syngeneic bone marrow cell transplantation.

Previously, we have shown the ability to induce experimental autoimmune conditions (e.g. SLE, APLS, Wegener's granulomatosis) following active immunization with the pathogenic autoantibody emulsified in adjuvant. The mice first develop anti-autoantibodies (Ab2: anti-id) and eventually generate anti-anti-autoantibodies (Ab3: anti-anti-id) which carry the same antigen binding characteristic as the autoantibody (Ab1). The appearance of the specific autoantibodies in mice sera was associated with the emergence of the compatible laboratory and with the clinical findings characteristic to the respective autoimmune disease. The effects of syngeneic bone marrow transplantation (BMT) on experimental anti-phospholipid syndrome (APS) were investigated. BALB/c mice were immunized with anti-cardiolipin monoclonal antibody (MoAb) named CAM and developed elevated serum titres of anti-phospholipid Abs accompanied by prolonged activated partial thromboplastin time, thrombocytopenia and a high percentage of fetal resorptions. These mice were then lethally irradiated and transfused with bone marrow (BM) cells (T cell depleted) from syngeneic naive mice. The titres of antiphospholipid antibodies were reduced in the recipients. The decrease in titre of autoantibodies was found to be related to depletion of antibody forming cells in vivo, associated with reduced proliferative response of lymph node cells to anti-cardiolipin MoAbs. The recipients showed improvement in clinical parameters following syngeneic BMT. The same recipients developed specific unresponsiveness to a second challenge with the anticardiolipin MoAb (CAM), but developed experimental systemic lupus erythematosus upon immunization with a monoclonal anti-DNA antibody. We conclude that acute myeloablative immunosuppression combined with syngeneic bone marrow transplantation may induce a state of tolerance to the pathogenic autoantibodies in mice with experimental APLS. Our results suggest that a similar approach may be useful in treating life-threatening autoimmune syndromes (e.g. catastrophic APLS) in clinical practice.

Animals↗

Multireactive pattern of serum autoantibodies in asymptomatic individuals with immunoglobulin A deficiency.

Selective immunoglobulin A (IgA) deficiency (sIgAD) is associated with certain autoimmune states. Increased production of autoantibodies and eventual development of overt autoimmune disease are related in part to genetic and environmental factors as well as to the immune deficiency. We surveyed serum specimens from 60 healthy subjects with sIgAD for the presence of 21 different autoantibodies by enzyme-linked immunosorbent assays. The frequencies of 16 autoantibodies were higher in sIgAD patients than in normal healthy controls. Autoantibodies to Jo-1 (28%), cardiolipin (21%), phosphatidylserine (20%), Sm (15%), asialo-GM1 (21%), sulfatide (32%), sulfoglucuronyl paragloboside (11%), and collagen type I (10%) were detected at high frequencies in comparison to those of normal healthy controls. Many of the serum samples were multireactive (i.e., exhibited binding to more than two autoantigens). Forty percent (24 of 60) of sIgAD serum samples reacted against six or more autoantigens; 10% (6 of 60) of sIgAD serum samples were not reactive with any of the 21 autoantigens. Three percent (7 of 209) of consecutive serum samples submitted for autoimmune antibody analysis that were positive for autoantibodies were from patients with IgA deficiency. Our finding of an increased frequency of autoantibodies in sIgAD patients supports the notion of polyclonal stimulation by repeated environmental stimuli as an etiologic mechanism. Alternatively, the increased frequency may be caused by a dysregulation of the immune response in such individuals. The mere detection of autoantibodies cannot predict whether a subject with sIgAD will develop an autoimmune disease or determine which specific disease will emerge.

Antigen-Antibody Reactions↗

Autoimmune aspects of primary pulmonary hypertension.

Although primary pulmonary hypertension (PPH) is considered to be an idiopathic condition, it has been postulated that autoimmunity may play a role in the pathogenesis of the disease. This argument has been based on frequent coexisting clinical and serological rheumatic findings. Moreover, approximately in a third of the patients with PPH, and antinuclear factor can be detected. Pulmonary hypertension may appear as a secondary complication to various autoimmune conditions. In light of these findings we examined sera derived from 40 patients diagnosed as having PPH for the presence of 18 different autoantibodies by the ELISA and immunofluorescent techniques. Of the 40 patients, 62.4% had circulating autoantibodies and 47.5% presented with multiantibody responses. Autoantibodies most commonly observed were antinuclear (42.5%), anti-ssDNA (25%) and antithyroglobulin (30%) antibodies. These results may imply that in a subgroup of patients with PPH the disease may be ascribed to an immune dysregulation or alternatively that autoantibodies accompany the disease progression as an epiphenomenon.

Antibodies, Antinuclear↗

Mechanisms of action of antiphospholipid antibodies in the antiphospholipid syndrome.

Antiphospholipid antibody syndrome (APS) is characterized by autoantibodies against negatively charged phospholipids in the serum, and clinically by multiple thromboses, thrombocytopenia, and recurrent fetal loss. The mechanism(s) by which the antibodies cause the clinical picture are not clear. We review the possible mechanisms of action of antiphospholipid (aPL) antibodies. Apparently, aPL antibodies act by interfering with coagulation, involving both endothelial cells, platelets, and humoral components, and affect pregnancy outcome by interfering with embryo implantation and fetal development.

Abortion, Spontaneous↗

Systemic lupus erythematosus and thymoma--a double-edged sword.

The coexistence of systemic lupus erythematosus (SLE) and thymoma is rare. We describe 2 female patients with this combination. A 48-year-old woman presented with dyspnea due to a left pleural effusion. Her past history revealed over the previous 3 years the development of anemia, thrombocytopenia, alopecia, pericardial effusion and proteinuria. Four months prior to this hospitalization, the patient was first admitted due to purpura. At that time, laboratory tests revealed an elevated sedimentation rate, elevated titers of ANA and anti-DNA. Chest X-ray demonstrated a widened mediastinum, and upon operation an encapsulated thymoma was excised. Four months following the thymectomy, the patient is unresponsive despite high dose steroid therapy. Another patient, a 30-year-old woman, presented with SLE (cutaneous, arthritis, anemia, positive ANA and high titers of anti-DNA) and thymoma simultaneously. Six years after thymectomy the patient is in SLE remission. Thymectomy in mice prone to autoimmunity (NZB/W mice) has been shown to accelerate the autoimmune manifestations. Conversely, the opposite effect is seen in MRL/lpr mice. The immunological effect of adult thymectomy on the course of human SLE remains to be established, on a larger series of patients. It seems that the heterogenicity of human patients is exemplified by the contrasting effects of thymectomy for thymoma in SLE patients.

Adult↗