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Y Shoenfeld

Publications and source records attributed to Y Shoenfeld.

At least 217 records · Page 12Linked to original sources

Autoantibodies associated with atherosclerosis.

Atherosclerosis is a multifactorial pathological process. In recent years, the immune factors associated with its initiation and progression have been investigated intensively. Several autoantigens and their respective autoantibodies have been suggested as factors in atherogenesis. This manuscript provides a review of autoantibodies directed towards oxidized low-density lipoprotein (oxLDL), cardiolipin, beta2-glycoprotein-I and heat-shock protein 60/65, and their association with human and murine atherosclerosis.

Animals↗

[Pulmonary adenocarcinoma in myasthenia gravis--autoimmunity and late development of malignancy].

We report a 75-year-old man with myasthenia gravis for many years, who was hospitalized because of cough, fever, and dyspnea. Chest x-ray revealed a bilateral pleural effusion. Adenocarcinomatous cells were found in the pleural fluid. Computerized tomography of the chest showed widespread pulmonary dissemination of the tumor. The relationship between myasthenia gravis, an autoimmune disease involving the motor end-plate, and malignancy (thymoma) has been widely recognized. Current literature documents few reports of lung malignancies with concurrent development of myasthenia gravis. A tentative explanation, based on current research, is provided for the possible role of myasthenia gravis and the late development of lung cancer. Moreover, a model for the autoimmune phenomenon and the development of late malignancies is provided with explicit explanations. It is important to search for occult, developing malignancies in newly diagnosed autoimmune diseases.

Adenocarcinoma↗

Anti-oxidized low density lipoprotein antibody determination as a predictor of restenosis following percutaneous transluminal coronary angioplasty.

Recent data suggests that autoimmune factors play an important role in the pathogenesis of atherosclerosis. In this context several autoantigens have been shown to elicit an immune response that results in accelerated atherosclerotic plaque formation. In the present study, we investigated whether elevated titers of anti-oxidized low density lipoprotein (oxLDL), anticardiolipin and antibodies to beta2-glycoprotein I (beta2GPI) can predict subsequent restenosis in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). A total of 74 consecutive patients (52 males, 22 females) with coronary artery disease were enrolled in the study. All patients underwent successful PTCA prior to which blood was drawn for the antibody analysis. The PTCA was followed by a clinical evaluation. Patients with recurrent chest pains underwent a repeated angiography and 34 of the 74 patients (46%) experienced restenosis. Patients positive for the presence of anti-oxLDL antibodies were more likely to develop restenosis within 6 months when compared with patients with no subsequent restenosis (relative-risk of 1.87; P< 0.05). Presence of anti-oxLDL antibodies was associated with hyperlipidemia (r = 0.25; P < 0.05) but not with other risk factors for atherosclerosis. Positivity for anticardiolipin or anti-beta2GPI antibodies which associate with a prothrombotic state, was not effective in predicting lumen narrowing. Thus, the presence of elevated levels of anti-oxLDL antibodies is associated with a higher risk for coronary restenosis following PTCA.

Aged↗

[Relapse of sarcoidosis after alternative medical treatment].

Reference to alternative medicine frequently appears in newspaper headlines, advertisements and in articles in medical journals. The practice of alternative medicine has increased, even as the number of critical articles warning of deleterious effects have also increased. Public demand is strong and growing, but there are no clear rules as to what is not permissible, particularly when treatment is not by qualified physicians. There are still no clear indications and contraindications for complementary (not alternative) medicine in patients with organic injuries and life-threatening conditions. However, it is obvious that in these patients complementary medicine should not be substituted for conventional therapy. We present a 32-year-old man with sarcoidosis who discontinued conventional therapy on his own initiative and began alternative medicine (homeopathy) with subsequent deterioration in his condition. He was hospitalized for a relapse of his sarcoidosis which required large doses of corticosteroids.

Adrenal Cortex Hormones↗

Immunolocalization of beta2-glycoprotein I (apolipoprotein H) to human atherosclerotic plaques: potential implications for lesion progression.

BACKGROUND: beta2-Glycoprotein I (beta2GPI) is a major antigenic target of antiphospholipid antibodies, which possesses natural anticoagulant properties. The aim of the present study was to determine its presence and localization within human atherosclerotic plaques and to study its association with endothelial cells and monocyte macrophages in vitro. METHODS AND RESULTS: Human atherosclerotic lesions were obtained after carotid endarterectomies and studied immunohistochemically with anti-beta2GPI as well as antibodies to CD4/CD8, macrophages, and adhesion molecules. In vitro, human umbilical vein endothelial cells (HUVECs) and U937 (myelomonocytic cell line) cells were investigated for their ability to associate with radiolabeled beta2GPI. We found beta2GPI to be abundantly expressed within the subendothelial regions and intimal-medial borders of human atherosclerotic plaques and to colocalize with CD4-positive lymphocytes. This observation was confirmed by Western blot applied on homogenates of atherosclerotic lesions with anti-beta2GPI antibodies. Both HUVECs and U937 cells bound labeled beta2GPI, and the process was inhibited by oxidized LDL and not by native LDL. CONCLUSIONS: The abundant presence of human beta2GPI within the lesions, its association with endothelial cells and macrophages, and its colocalization with CD4-positive lymphocytes suggests that it may serve as a target for an immune-mediated reaction that can influence lesion progression.

Animals↗

Prevention of experimental antiphospholipid syndrome and endothelial cell activation by synthetic peptides.

Antiphospholipid syndrome (APS) is characterized by recurrent fetal loss, repeated thromboembolic phenomena, and thrombocytopenia. The syndrome is believed to be caused by antiphospholipid beta-2-glycoprotein-I (beta2GPI)-dependent Abs or anti-beta2GPI Abs by themselves. Using a hexapeptide phage display library, we identified three hexapeptides that react specifically with the anti-beta2GPI mAbs ILA-1, ILA-3, and H-3, which cause endothelial cell activation and induce experimental APS. To enhance the binding of the peptides to the corresponding mAbs, the peptides were lengthened to correspond with the site of the beta2GPI epitope being recognized by these mAbs. As a result, the following three peptides were prepared: A, NTLKTPRVGGC, which binds to ILA-1 mAb; B, KDKATFGCHDGC, which binds to ILA-3 mAb; and C, CATLRVYKGG, which binds to H-3 mAb. Peptides A, B, and C specifically inhibit both in vitro and in vivo the biological functions of the corresponding anti-beta2GPI mAbs. Exposure of endothelial cells to anti-beta2GPI mAbs and their corresponding peptides led to the inhibition of endothelial cell activation, as shown by decreased expression of adhesion molecules (E-selectin, ICAM-1, VCAM-1) and monocyte adhesion. In vivo infusion of each of the anti-beta2GPI mAbs into BALB/c mice, followed by administration of the corresponding specific peptides, prevented the peptide-treated mice from developing experimental APS. The use of synthetic peptides that focus on neutralization of pathogenic anti-beta2GPI Abs represents a possible new therapeutic approach to APS.

Animals↗

Molecular mimicry between host and pathogen: examples from parasites and implication.

The studies summarized in this paper suggest that parasites may trigger activation of autoimmune mechanisms. The association between parasites and autoimmunity could by manifested by the development of pathogenic anti-parasitic antibodies and cytotoxic T cells that attack and damage self tissues as a result of molecular mimicry between host and parasites. On the other hand, the homology between self and parasitic antigens may enable parasites to protect themselves from the immune system and to induce a state of immunosuppression. Although classic autoimmune diseases have not been shown to be more common amongst patients with chronic parasitic infections than in the general population, it is clear that autoimmune activity does occur in patients with chronic parasitic infections. It is possible that infection with parasites and other microbial agents may be followed by the activation of the immune system and, in genetically predisposed individuals, by loss of functional tolerance to self, activation of autoreactive cell that leads to progression to an overt autoimmune disease.

Animals↗