Search PubMed⌕ Search

Biomedical subjects

Y Shoenfeld

Publications and source records attributed to Y Shoenfeld.

At least 253 records · Page 14Linked to original sources
PubMed1999

Serologic and clinical response to treatment of systemic vasculitis and associated autoimmune disease with intravenous immunoglobulin.

BACKGROUND: Autoimmune vasculitides cannot always be controlled by steroids and immunosuppressive drugs. Intravenous immunoglobulin (IVIg) treatment was found beneficial in several vasculitides including systemic and organ-specific diseases. In this article we tested whether the beneficial clinical response of IVIg treatment in vasculitides was accompanied by a decrease in vasculitis-associated autoantibody levels. METHODS: Ten patients diagnosed as having vasculitis were treated with high-dose (2 g/kg) IVIg monthly, in a 5-day schedule. In all the patients, other therapeutic measures failed to control disease progression prior to IVIg treatment. Each patient received between 1 and 6 treatment courses. All patients were evaluated for the levels of 5 autoantibodies (Abs) related to vasculitis before and after each treatment course. RESULTS: In 6 out of the 10 patients, a beneficial clinical response followed IVIg treatment. Moreover, no treatment-related adverse effects were observed in any of the patients. Anti-myeloperoxidase antibodies and cytoplasmic-antineutrophil cytoplasmic antibodies levels decreased concomitantly with the clinical improvement observed in the patients with Churg-Strauss vasculitis and Wegener's granulomatosis, respectively. Levels of cytoplasmic-antineutrophil cytoplasmic antibodies (ANCA) with specificity for bacteridial/permeability-increasing protein and human lysosomal-associated membrane protein increased after each treatment course, but returned to normal values before the following one. CONCLUSIONS: When other therapeutic measures, such as immunosuppressive therapy, fails to control disease manifestations in patients with vasculitides, IVIg is a possible effective intervention method with a high response rate. IVIg probably exerted its effects on disease progression via different mechanisms. Among these mechanisms, a decrease in relevant Ab levels is often found (probably by anti-idiotypes in IVIg), and thus ANCA levels are expected to associate with disease activity.

Adult↗
PubMed1999

Enhancement of atherosclerosis in beta-2-glycoprotein I-immunized apolipoprotein E-deficient mice.

We have previously shown that low density lipoprotein receptor-deficient (LDL-RD) mice immunized with beta2-glycoprotein I (beta2GPI; a target of autoimmune anticardiolipin antibodies) developed enhanced early atherosclerosis, when fed a normal chow diet. The current study was undertaken to evaluate the effect of immunization with beta2GPI and the addition of a high fat diet on the progression of atherosclerosis in the apolipoprotein E (ApoE)-deficient mouse. Six-week-old female ApoE-deficient mice (n = 10) were immunized subcutaneously with either human beta2GPI or with ovalbumin, both emulsified in complete Freund's adjuvant and fed a high fat diet for 6 weeks. The beta2GPI-immunized mice were found to develop accelerated atherosclerosis when compared with their ovalbumin-immunized littermates (aortic lesion area of 137,500 +/- 13,801 vs. 72,444 +/- 14,465 microm2, respectively; p = 0.0067). The beta2GPI-immunized mice developed high titers of anti-beta2GPI antibodies, 10 days after the procedure, which were sustained until the sacrifice. LDL extracted from both study groups displayed similar susceptibility to ex vivo oxidation. These results confirm our previous study in which we found increased atherosclerosis in beta2GPI-immunized LDL-RD mice fed a chow diet. In the current study we show that the proatherogenic effect of beta2GPI immunization is maintained despite high cholesterol levels and is not associated with increased susceptibility of LDL to ex vivo oxidation.

Animals↗
PubMed1999

Enhanced fatty streak formation in C57BL/6J mice by immunization with heat shock protein-65.

Recent data suggest that the immune system is involved in atherogenesis. Thus, interest has been raised as to the possible antigens that could serve as the initiators of the immune reaction. In the current work, we studied the effects of immunization with recombinant heat shock protein-65 (HSP-65) and HSP-65-rich Mycobacterium tuberculosis (MT) on early atherogenesis in C57BL/6J mice fed either a normal chow diet or a high-cholesterol diet (HCD). A rapid, cellular immune response to HSP-65 was evident in mice immunized with HSP-65 or with MT but not in the animals immunized with phosphate-buffered saline (PBS) alone. Early atherosclerosis was significantly enhanced in HCD-fed mice immunized with HSP-65 (n=10; mean aortic lesion size, 45 417+/-9258 microm2) or MT (n=15; 66 350+/-6850 microm2) compared with PBS-injected (n=10; 10 028+/-3599 microm2) or nonimmunized (n=10; 9500+/-2120 microm2) mice. No fatty streak lesions were observed in mice fed a chow diet regardless of the immunization protocol applied. Immunohistochemical analysis of atherosclerotic lesions from the HSP-65- and MT-immunized mice revealed infiltration of CD4 lymphocytes compared with the relatively lymphocyte-poor lesions in the PBS-treated or nonimmunized mice. Direct immunofluorescence analysis of lesions from HSP-65- and MT-immunized mice fed an HCD exhibited extensive deposits of immunoglobulins compared with the fatty streaks in the other study groups, consistent with the larger and more advanced lesions found in the former 2 groups. This model, which supports the involvement of HSP-65 in atherogenesis, furnishes a valuable tool to study the role of the immune system in atherogenesis.

Animals↗
PubMed1999

Increased endothelial cell expression of alpha3beta1 integrin in cardiac valvulopathy in the primary (Hughes) and secondary antiphospholipid syndrome.

The objective of this work was to determine markers of endothelial cell activation in valves from patients with antiphospholipid syndrome (APS) and heart valve involvement, in order to establish a role for endothelial cells in the pathogenesis of the valvular disease. Sixteen valves from ten patients with APS, obtained from autopsies or removed during valve replacement, were studied. Two groups of valves were used as controls. One group included seven normal valves from patients who died from non-cardiac diseases. The other group of valves were obtained from patients with bacterial endocarditis during autopsies or valve replacement operations. Immunoperoxidase and immunofluorescence stainings with antibodies to human immunoglobulins, endothelial cells, alpha3beta1 integrin, collagen IV, laminin and fibronectin were employed. Three histopathological patterns were apparent: normal valves, valves with verrucous endocarditis and valves with fibrocalcific changes. In all the valves with verrucous endocarditis the following findings were observed: (1) increased expression of the alpha3beta1 integrin on the endothelial cells, (2) increased amount of collagen IV, laminin and fibronectin, (3) proliferation of blood vessels and (4) linear subendothelial deposition of immunoglobulins and complement. The valves with fibrocalcific changes were deformed and showed a thick layer of collagen IV, laminin and fibronectin, yet in two valves the indothelial cells showed an expression of the alpha3beta1 integrin. The control valves did not express the integrin and had only a thin subendothelial band of collagen IV. In valves from patients with APS, 1 markers of endothelial cell activation are upregulated while the inflammatory exudate is scant. There is also a prominent deposition of immunoglobulins in the valves from patients with APS, suggesting a possible association between the deposition of the antibodies and the activation of the endothelial cells in APS.

Actins↗
PubMed1999

A study of 20 SLE patients with intravenous immunoglobulin--clinical and serologic response.

OBJECTIVE: To test the clinical response of systemic lupus erythematosus (SLE) patients to intravenous immunoglobulins (IVIg), and whether the clinical response of IVIg treatment in SLE is accompanied by modification of SLE-associated autoantibodies/antibodies (Abs) and complement levels. METHODS: Twenty SLE patients were treated with high-dose (2 g/kg) IVIg monthly, in a 5-d schedule. Each patient received between 1-8 treatment courses. They were evaluated for the clinical response, Systemic Lupus Activity Measure (SLAM) score before and after IVIg, levels of antinuclear antibody (ANA), dsDNA (double-stranded DNA), SS-A or SS-B, ENA (extractable nuclear antigens), C3 and C4 levels before and after the treatment, and before and after each treatment course. RESULTS: A beneficial clinical response following IVIg treatment was noted in 17 out of 20 patients (85%). Few clinical manifestations responded more to treatment: arthritis, fever, thrombocytopenia, and neuropsychiatric lupus. In 9 patients evaluated before and after IVIg, mean SLAM score decreased from 19. 3+/-4.7 to 4+/-2.9 (P<0.0001). There was a tendency towards abnormal levels of complement and Abs before IVIg courses among the treatment responders compared with the non-responders, and similarly the former tended to have normalization of their abnormal levels more than the latter. These differences were found statistically significant only with respect to C4 and SS-A or SS-B levels before IVIg courses. CONCLUSION: IVIg has a high response rate among SLE patients. A combination of clinical manifestations, Abs and complement levels may aid in the future in predicting who among SLE patients will benefit more from IVIg treatment.

Adult↗
PubMed1999

Beta2 glycoprotein I containing immune-complexes in lupus patients: association with thrombocytopenia and lipoprotein (a) levels.

In this study we determined the prevalence and clinical associations of immune-complexes-containing beta-2-glycoprotein I (beta2GPI) in randomly selected SLE patients. We studied 38 consecutive SLE patients attending the Rheumatology Unit. Previous arterial or venous-thrombosis were documented by the appropriate diagnostic test. Lipid profile including total cholesterol, LDL, VLDL, HDL and Lp(a) levels were determined from the sera of the fasting patients. Antibodies to cardiolipin, oxidized LDL and beta2GPI were detected employing ELISA. Beta2GPI containing IgG immune-complexes were assayed by using a dot-blot assay. Fourteen SLE patients (36.8%) were found to be positive for the presence of IgG anti-beta2GPI antibodies. Ten of the SLE patients (26.3%) were found to have high levels of beta2GPI containing immune-complexes. There was a positive correlation between beta2GPI-IC levels and the occurrence of thrombocytopenia in the patients (P < 0.05). Furthermore, patients with SLE and venous thrombosis had higher levels of beta2GPI-IC when compared with thrombosis-free patients or with healthy controls (P < 0.05). Patients with higher Lp(a) levels (> 50 mg/dl) possessed higher levels of beta2GPI-IC as compared with patients with lower Lp(a) concentration (< 20 mg/dl) (P < 0.05). These results suggest that IC-containing beta2GPI can help in defining a subpopulation of SLE patients with increased risk of thrombocytopenia and further aid in resolving mechanisms of immune-mediated tissue damage.

Adult↗
PubMed1999

Antiphospholipid antibodies permeabilize and depolarize brain synaptoneurosomes.

Antiphospholipid antibodies (aPL) are associated with neurological diseases such as stroke, migraine, epilepsy and dementia and are thus associated with both vascular and non-vascular neurological disease. We have therefore examined the possibility that these antibodies interact directly with neuronal tissue by studying the electrophysiological effects of aPL on a brain synaptosoneurosome preparation. IgG from patients with high levels of aPL and neurological involvement was purified by protein-G affinity chromatography as was control IgG pooled from ten sera with low levels of aPL. Synaptoneurosomes were purified from perfused rat brain stem. IgG from the patient with the highest level of aPL at a concentration equivalent to 1:5 serum dilution caused significant depolarization of the synaptoneurosomes as determined by accumulation of the lipophylic cation [3H]-tetraphenylphosphonium. IgG from this patient as well as IgG from two elderly patients with high levels of aPL were subsequently shown to permeabilize the synaptosomes to labeled nicotinamide adenine dinucleotide (NAD) and pertussis toxin-ADP-ribose transferase (PTX-A protein) as assayed by labeled ADP-ribosylation of G-proteins in the membranes. No such effects were seen with the control IgG. aPL may thus have the potential to disrupt neuronal function by direct action on nerve terminals. These results may explain some of the non-thromboembolic CNS manifestations of the antiphospholipid syndrome.

Adult↗
PubMed1999

Atherosclerosis-related markers in systemic lupus erythematosus patients: the role of humoral immunity in enhanced atherogenesis.

Systemic Lupus Erythematosus (SLE) patients experience premature atherosclerosis. A deranged lipid metabolism and use of immunosuppressive medications accounts partially for the accelerated process. The role of autoimmunity in atherosclerosis has recently been highlighted. Autoantigenic determinants thought to play a role in the development of atherosclerosis include: modified lipoproteins, heat shock proteins and beta2-glycoprotein I (a target of 'autoimmune' anticardiolipin antibodies). In this present work we determined autoimmune markers which may be associated with premature atherosclerotic process found in SLE patients. We have found that antibodies to oxLDL were raised in the sera of lupus patients and cross-reacted with cardiolipin and with beta2GPI. OxLDL containing immune-complexes of the IgG and IgM isotypes were both elevated in the SLE patients as compared with healthy controls. Patients with high Lipoprotein (a) concentrations (>30 mg/dl) had higher levels of IgM oxLDL-containing immune-complexes. IgM but not IgG anti-HSP-65 antibodies were elevated in the lupus patients and levels of oxLDL containing immune-complexes correlated positively with the presence of anti-HSP 65 antibodies. Lysophosphatidylcholine (LPC) is a peroxide-derivative formed during LDL oxidation, was shown to evoke a humoral response in healthy subjects. Antibodies to lysophosphatidylcholine of the IgG but not the IgM isotype were reduced in SLE patients compared with controls, suggesting it may be 'consumed' into oxLDL containing immune complexes. Therefore, SLE patients exhibit a humoral autoimmune response towards the antigenic candidates incriminated in the progression of atherosclerosis. These findings may help identify factors that are involved in accelerating atherogenesis in SLE patients.

Adult↗
PubMed1999

Treatment of chronic bilateral pleural effusions with intravenous immunoglobulin and cyclosporin.

A 48 y old woman with unremarkable medical history was admitted with bilateral pleural effusions; even though the fluid was drained, it re-accumulated and necessitated many repeated drainages in the following 2.5 y (56 hospitalisations). The patient underwent an extensive diagnostic work-up that disclosed elevated serum antinuclear antibodies, serum anti-dsDNA antibodies, pleural fluid anti-dsDNA and decreased pleural fluid C3 and C4. During that period she has been treated with a variety of immunomodulating agents, several pleural talcage and pleurectomy, without any apparent response. Thereafter, she received six courses of IVIg (2 g/kg body weight) in monthly intervals, followed by four months treatment with cyclosporin. This treatment resulted in gradual and eventually complete disappearance of the pleural effusion, and now after more than 2 y the patient is free of symptoms and receives no further medications.

Antibodies, Antinuclear↗
PubMed1999

Immunomodulation of various autoimmune diseases by intravenous immunoglobulin.

Intravenous immunoglobulin (IVIg) is currently an accepted treatment for some autoimmune diseases and it has recently been used empirically in various other autoimmune conditions. This review discusses the role of IVIg in autoimmunity, mainly in systemic lupus erythematosus and systemic vasculitis. Clinical experience with IVIg, as well as its mechanisms of action with special emphasis on modulation of the idiotypic network, are also presented.

Journal Article↗
PubMed1999

Antibodies to the cytoplasm, cell membrane and nuclear membrane of malignant neoplasms in pooled normal human polyspecific immunoglobulin G.

IVIg is a preparation of normal polyspecific IgG obtained from pooled plasma of a large number of healthy donors. IVIg treatment of patients with chronic lymphocytic leukemia induced a reduction in the total number of lymphocytes in the peripheral blood. Regression of Kaposi's sarcoma was also noted in an HIV patient treated with IVIg. The aim of this study was to determine whether F(ab')2 prepared from IVIg binds to cellular structures of different tumor tissues. Biotinylated F(ab')2 was prepared from 3 different preparations of IVIg and from affinity purified IgG from a patient with multiple myeloma. Direct immunohistochemistry using a streptavidin peroxidase staining method was performed on biopsy samples of 18 different tumor tissues. Positive staining of the cytoplasm, cell membrane and nuclear membrane of several types of malignant tumors by F(ab')2 from IVIg was immunohistochemically demonstrated. Nuclear staining of tumor cells by IVIg was rare. IVIg bound to different tumors of epithelial origin, especially colon carcinoma, breast carcinoma and squamous cell carcinoma of the lung. Malignant tumors of mesenchymal origin such as leiomyosarcoma have also demonstrated positive staining by IVIg. IVIg contains antibodies to the cytoplasm, nuclear membrane and cell membrane of different malignant tumors especially of epithelial origin. This binding might provide a basis for the assumption that IVIg treatment of cancer patients may induce antibody dependent cell mediated cytotoxicity response against tumors, and implies that it can be potentially beneficial as adjuvant treatment of malignant diseases.

Antibody Affinity↗
PubMed1999

Anti-cardiolipin, anti-endothelial-cell and anti-malondialdehyde-LDL antibodies in uremic patients undergoing hemodialysis: relationship with vascular access thrombosis and thromboembolic events.

Patients with chronic renal failure requiring regular hemodialysis are known to be prone to thromboembolic events due to a hypercoagulable state. Vascular access thrombosis (VAT; including thrombosis of the vascular shunt or graft) represents a serious complication and jeopardizes life in these patients. In the current study, conducted on 81 consecutive patients from the Hemodialysis Unit, we have employed ELISA for the estimation of various autoantibody levels (anti-endothelial cell antibodies, anti-cardiolipin, anti-beta 2GPI and anti-modified LDL antibodies) and correlated them with the occurrence of thromboembolic events in general, and VAT in particular. We have found that the levels of antibodies reactive with human umbilical vein endothelial cells (HUVEC) but not with other EC lines (microvascular or EaHy 929) were significantly higher in hemodialysed patients with VAT in comparison with patients with no VAT (p = 0.001). A weaker but yet positive correlation was observed between the levels of anti-HUVEC and anti-cardiolipin antibodies and the occurrence of thromboembolic events including deep vein thrombosis, pulmonary infarction, cerbrovascular events and VAT (both p-values equal 0.02). Anticardiolipin antibodies (aCL) were not cross reactive with beta 2GPI or with HUVEC. Antibodies to modified LDL, although higher in hemodialyzed patients, did not correlate with thromboembolic events. The results of this study suggest that antibodies to HUVEC may prove as a fairly good marker of VAT in hemodialysis. High levels of aCL are weakly associated with thromboembolic events and antibodies to modified LDL do not correlate with a prothrombotic state.

Adult↗
PubMed1999

Elevated homocysteine levels in patients with Raynaud's syndrome.

OBJECTIVE: Patients with Raynaud's phenomenon (RP) have vasomotor dysregulation, the etiology of which has not yet been elucidated. We investigated plasma levels of homocysteine and folate in patients with primary or secondary RP in comparison with healthy subjects. METHODS: Plasma from patients with RP, either primary (n = 10) or secondary to scleroderma (n = 10), and from healthy subjects (n = 20) was obtained for homocysteine determination using high performance liquid chromatography. RESULTS: Patients with primary and secondary RP had significantly higher homocysteine concentrations (mean 15.5 +/- 4.1 and 11.6 +/- 6.2 micromol/l, respectively; p < 0.05) compared to healthy individuals (mean 5.9 +/- 2.0 micromol/l). Patients with primary RP had significantly lower plasma levels of folate in comparison with patients with secondary RP or healthy individuals. CONCLUSION: This is the first study to show higher plasma levels of homocysteine in patients with RP. Given the obscure etiology of this disorder, these findings may provide new clues in the understanding of vasomotor dysfunction in RP.

Adult↗