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Y Tomer

Publications and source records attributed to Y Tomer.

68 records · Page 4Linked to original sources
PubMed1991

Superior vena cava occlusion in a patient with antiphospholipid antibody syndrome.

A 55-year-old woman with a lupus like disease, associated with the lupus anticoagulant, was admitted because of facial edema. Her facial swelling was previously attributed to the steroids she had been taking and they were tapered without improvement. Laboratory tests revealed high titers of anticardiolipin antibodies. Computerized tomography of her chest and Doppler ultrasound examination of her neck veins demonstrated a thrombus in the superior vena cava. She was treated with heparin and was maintained with longterm warfarin therapy with uneventful followup. Superior vena cava obstruction should be added to the long list of thromboembolic complications of the antiphospholipid syndrome.

Antibodies↗
PubMed1989

The significance of T suppressor cells in the development of autoimmunity.

Despite intensive research, autoimmune-disease pathogenesis is still an enigma, but in the past decade Ts-cell defects have assumed a central role in this pathogenesis. Ts-cell dysfunctions have been reported in numerous autoimmune diseases (e.g. SLE, autoimmune thyroid disease, myasthenia gravis) and in animal models of autoimmune diseases. Therefore, it is currently believed that Ts cells are responsible for maintaining self-tolerance and that perturbations in suppressor functions may initiate development of autoimmune diseases. Ts-cell abnormalities can result from LCTA production, intrinsic biochemical alterations, genetic susceptibility, or environmental factors. Since Ts-cells dysfunctions are believed to initiate autoimmunity, it may be possible to treat autoimmune diseases by correcting the suppressor defects, and indeed, preliminary trials in this direction are promising.

Animals↗
PubMed1988

The significance of natural autoantibodies.

Since Burnet first introduced his "forbidden clones" theory, the discrimination between self and non-self and the physiologic mechanisms of avoiding autoimmunity remained an enigma. The realization in the past two decades that autoantibodies reacting with various self antigens are common in normals has led to intensive research on the origin and physiologic role of these "natural autoantibodies". After reviewing the extensive literature on the appearance of natural autoantibodies in normal animals and humans, and the studies proving unequivocally that natural autoantibodies are coded by germ line genes, we will discuss the current hypotheses explaining their appearance and physiologic role. Despite the fact that numerous hypotheses explaining the origin of natural autoantibodies have been postulated only the two important ones will be discussed. The first, proposed by Cunningham, holds that clonal deletion as viewed by Burnet operates in early life; however, later in life all autoreactive B cells not eliminated during ontogeny are prevented from expanding and secreting anti-self antibodies by a compensatory suppressor mechanism. Therefore, natural autoantibodies are postulated to be autoantibodies which are produced only in minute quantities allowed by the suppressor mechanism. The second hypothesis views autoantibody formation as a result of cross reaction between foreign and self determinants. It is suggested that the part of the B cell population which gives rise to autoantibodies carries a polyspecific receptor; fixation of a foreign antigen to this receptor induces the B cell to undergo a series of divisions and mutations, which under the selective pressure of the antigen leads to production of a highly specific antibody. Thus natural autoantibodies may constitute the antibodies secreted by these B cells prior to encountering foreign antigens. The biologic role of natural autoantibodies is also elusive. The common denominator to all the theories dealing with that puzzling question is the view that natural autoantibodies have a positive role in normal immune reactions, perhaps even an essential role without which normal immune function would be disrupted. Grabar suggested that natural autoantibodies are part of a physiologic mechanism for cleansing the organism of self and non-self products in which classical antibodies serve to clear the body of foreign invading agents, while natural autoantibodies rid the organism of its own catabolic products.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed1988

Ageing and autoantibodies.

Immune responsiveness decreases with age, while the production of autoantibodies increases, indicating that these are end results of perturbations in the regulatory mechanisms of the immune system. The effects of ageing on the immune system are reviewed.

Aged↗
PubMed1988

HLA antigens in patients with Heberden's nodes.

Tissue typing was performed on a group of 51 patients with Heberden's nodes (HN) (45 Ashkenazic and 6 non-Ashkenazic Jews). The frequency of HLA-DR2 was higher (P = 0.03) in the Ashkenazic patients than in the Ashkenazic controls. However, the association was not significant after correction for the number of tested alleles at that locus. In the second part of the study, HLA typing was performed on subjects from a family with multiple HN occurrences. Of the 13 family members typed, 9 had HN: 6 of these had the haplotype A2, Bw35, DR2. We conclude that the development of HN may be influenced by genetic factors. Our results may suggest an association between HN and HLA-DR2 in Ashkenazic Jews.

Female↗
PubMedDate not supplied

Autoantibodies, autoimmunity and cancer (review).

There is a strong association between neoplasms and autoimmune diseases. Numerous autoimmune phenomena have been reported in malignancies and conversely: malignant tumors are diagnosed in increasing frequency in autoimmune conditions. We review the most common autoimmune diseases and autoantibodies found in malignancies, discuss the therapeutic role of these autoantibodies in cancer, and summarize the current knowledge on malignant transformation in autoimmunity.

Antibodies, Neoplasm↗
PubMedDate not supplied

Cytokines in experimental autoimmune vasculitis: evidence for a Th2 type response.

OBJECTIVE: To investigate the pathogenic role of cytokines in the development of experimental autoimmune vasculitis. METHODS: BALB/c mice were immunized with human IgG-ANCA from a patient with WG. Control mice were immunized with normal human IgG. Levels of mouse IgG-ANCA and other autoantibodies were determined. The mice lungs and kidneys were examined for the development of vasculitis. Levels of interleukin-1 beta (IL-1 beta), IL-2, IL-4, IL-6, interferon gamma (IFN gamma) and TNF alpha were determined by ELISA two weeks after immunization of the mice. RESULTS: Mice immunized with human IgG-ANCA developed anti-human IgG-ANCA (= Ab2) and anti-anti-human IgG-ANCA (mouse IgG-ANCA = Ab3), while the controls did not develop these antibodies. The mice that were immunized with human IgG-ANCA developed perivascular mononuclear cell infiltrates in the lungs, suggesting vasculitis. Levels of IL-4, IL-6 and TNF alpha but not IL-1 beta, IL-2 and IFN gamma were significantly elevated in the mice 2 weeks after immunization with IgG-ANCA. CONCLUSION: Our results suggest a pathogenic role for IL-4, IL-6 and TNF alpha in the initiation phase of autoimmune vasculitis. This suggests that a Th2 type immune response is responsible for the initiation of experimental autoimmune lung vasculitis, similar to Wegener's granulomatosis in humans.

Animals↗
PubMedDate not supplied

Successful treatment of psychosis secondary to SLE with high dose intravenous immunoglobulin.

A 23-year-old woman with SLE was admitted because of severe psychosis manifested by depression, delusions and the inability to perform minimal daily activities. The patient refused treatment with steroids, but was later convinced to try treatment with intravenous immunoglobulin (IVIG). Following treatment with IVIG a marked improvement was noted in her mental status and she was discharged. During a follow-up period of 18 months she resumed normal life; she does not receive any drugs currently and no psychiatric abnormalities have been noted. It is suggested that IVIG may be considered in the treatment of lupus cerebritis, especially when serious complications develop and other treatment modalities are ineffective.

Adult↗
PubMedDate not supplied

Levels of lupus autoantibodies in pregnant SLE patients: correlations with disease activity and pregnancy outcome.

OBJECTIVE: To follow the levels of lupus autoantibodies throughout pregnancy in a large cohort of pregnant SLE patients, and to examine whether they correlate with disease activity and pregnancy outcome. METHODS: 54 pregnancies in 46 SLE patients, and 70 control pregnant women were followed in the study. All patients were receiving steroid treatment. Titers of antibodies to ssDNA, dsDNA, histones, cardiolipin (CL) and phosphatidylserine (PS) were determined at the first, second, and third trimester and post-partum by ELISA. RESULTS: Overall the average levels of autoantibodies in all the patients were within the normal range, except for the average levels of anti-dsDNA antibodies which were elevated during the second trimester. Eight women (14.5%) had active disease during pregnancy, and there was a significant correlation between the levels of anti-dsDNA and the risk of disease activity (p = 0.0225). There were 7 fetal losses. There was a tendency for correlation between elevated anti-dsDNA levels, and anti-CL levels and the risk of fetal loss; however, this did not reach statistical significance (p = 0.0685, and 0.0881, respectively). There was a significant correlation between the levels of anti-dsDNA antibodies and the risk of preterm delivery (p = 0.0331). CONCLUSIONS: Pregnancy in SLE patients is associated with significant complications to both the mother and the fetus. Anti-dsDNA levels seem to correlate with the risk of disease exacerbation, and prematurity. Elevated levels of anti-dsDNA and anti-CL may suggest an increased risk of fetal loss.

Adult↗