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ROSE
Women and autoimmune diseases.Fairweather
D, Rose NR. [abstract only]
"Autoimmune diseases affect approximately 8% of the population, 78% of whom are women. The reasons for the high prevalence in women are unknown, but circumstantial evidence links autoimmune diseases with preceding infections. Animal models of autoimmune diseases have shown that infections can induce autoimmune disease. For example, coxsackievirus B3 (CB3) infection of susceptible mice results in inflammation of the heart (myocarditis) that resembles myocarditis in humans. The same disease can be induced by injecting mice with heart proteins mixed with adjuvant(s), which indicates that an active infection is not necessary for the development of autoimmune disease. We have found that CB3 triggers autoimmune disease in susceptible mice by stimulating elevated levels of proinflammatory cytokines from mast cells during the innate immune response. Sex hormones may further amplify this hyperimmune response to infection in susceptible persons, which leads to an increased prevalence of autoimmune diseases in women."
Autoimmune disease 2002: an overview.Rose
NR. [abstract only]
"Autoimmune disease includes a large spectrum of clinically distinct entities that share a common etiology, a misguided, self-directed immune response. Collectively, they are major contributors to morbidity and mortality. Normally, the body utilizes a number of strategies to avoid the pathologic consequences of autoimmune reactions, but these defenses may fail for a combination of hereditary and environmental factors. Infection has long been regarded as a common environmental trigger of autoimmune disease. Our laboratory has developed a mouse model of myocarditis induced by Coxsackievirus B3 infection and demonstrated some of the steps involved in the transition from an infection to an autoimmune disease. Such basic studies may suggest improved treatment or preventive measures for this group of diseases."
Iodine: an environmental trigger of thyroiditis.Rose
NR, Bonita R, Burek CL.
"Like
most autoimmune diseases of humans, chronic lymphocytic (Hashimoto's)
thyroiditis results from the combination of a genetic predisposition and an
environmental trigger. A body of clinical and epidemiologic evidence points to
excessive ingestion of iodine as an environmental agent. In genetically
determined thyroiditis in animals, iodine enrichment has been shown to increase
the incidence and severity of disease. Its mechanism of action is still
uncertain. Using a new animal model of autoimmune thyroiditis, the NOD.H2(h4)
mouse, we have been able to show that iodine enhances disease in a
dose-dependent manner. Immunochemical studies suggest that iodine incorporation
in the thyroglobulin may augment the antigenicity of this molecule by increasing
the affinity of its determinants for the T-cell receptor or the MHC-presenting
molecule either altering antigen processing or by affecting antigen
presentation."
Mechanisms of autoimmunity.Rose NR. Semin Liver Dis. 2002 Nov;22(4):387-94. Review.
"The immune system is capable of recognizing any molecule that enters the body through a parenteral route. For that purpose, the lymphocyte population generates a large, diverse repertoire of receptors. Inevitably, many of these receptors recognize endogenous host antigens as well as exogenous molecules. Thus, self-reactive B cells and T cells are present in normal individuals and are potentially capable of producing an autoimmune response. The host consequently depends on certain mechanisms to avoid the harmful effects of autoimmunity. These mechanisms include negative selection in the thymus and bone marrow to delete the higher-affinity T and B cells and peripheral regulatory mechanisms, such as anergy, ignorance, and suppression. Despite such protective mechanisms, autoimmune diseases, collectively, are common in industrialized societies, even though individually most autoimmune diseases are rare. The diseases present differently depending on the site of pathology but share many fundamental mechanisms."
From infection to autoimmunity.Fairweather
D, Kaya Z, Shellam GR, Lawson CM, Rose NR. [abstract only]
"We have investigated two models of virally-induced autoimmune myocarditis in mice using widely different infectious agents. Infection of susceptible BALB/c mice with either Coxsackievirus or murine cytomegalovirus results in the development of acute myocarditis from day 7-14 after infection, and chronic myocarditis from day 28 onwards. The chronic phase of myocarditis is associated with mononuclear infiltration of the myocardium and the production of autoantibodies to cardiac myosin, although infectious virus cannot be detected past day 14 of infection. T cells and autoantibodies have been shown to be important for the development of autoimmune myocarditis. Many researchers have investigated the role of molecular mimicry in the development of myocarditis after viral infection. This review explores the 'adjuvant' effect of infection on the innate immune response and how this determines the progression to autoimmune disease. We show that NK cells protect against the development of disease, while complement and complement receptors are involved in the development of autoimmune myocarditis induced by inoculation with virus or cardiac myosin, respectively. Our results suggest that the innate immune response to viral and self-antigens may determine whether susceptible strains of mice progress to chronic autoimmune disease. These findings have broad implications for understanding the role of infection in inducing autoimmune disease."
Autoantibodies to thyroglobulin in health and disease.Rose
NR, Burek CL. [abstract only]
"Thyroglobulin (Tg)--a heavily glycosylated, iodinated protein--is a major autoantigen in autoimmune thyroiditis. Tg also induces thyroiditis by immunization of experimental animals. Humans with chronic lymphocytic thyroiditis characteristically produce autoantibodies to thyroglobulin, but similar autoantibodies are also found in some clinically normal, euthyroid individuals. A comparison of the fine specificity of autoantibodies in humans and in experimentally immunized mice was carried out, based on their ability to inhibit a panel of monoclonal antibodies (MAbs). Patients with autoimmune thyroid disease, as well as normal individuals, produced autoantibodies mainly to the conserved, cross-reactive determinants of thyroglobulin. Patients developed additional autoantibodies to species-restricted epitopes. The determinants recognized by patients with Graves' disease differed in some respects from epitopes recognized by thyroiditis patients or patients with differentiated thyroid carcinoma. Similarly, mice that are genetically susceptible to thyroiditis produced autoantibodies that reacted with the mouse-specific antigenic determinants. Using an autoantibody that reacts with one of the epitopes associated with thyroiditis, a reactive 15-kDa fragment of human Tg--localized at the carboxy end of the molecule--was isolated and sequenced. Iodine plays an important role in the precise specificity of the disease-associated epitope, since T cells from patients with thyroiditis react with iodinated but not noniodinated human thyroglobulin. Addition of iodine to Tg generates new or exposes cryptic epitopes. Use of a selected MAb as a surrogate for the T-cell receptor suggests that a specific iodine-containing epitope is sometimes involved in recognition. Finally, thyroglobulin-reactive autoantibodies exhibit proteolytic activity on thyroglobulin."
Linking iodine with autoimmune thyroiditis.Rose
NR, Rasooly L, Saboori AM, Burek CL. [abstract only]
"A great deal of circumstantial evidence has linked iodine with the rising incidence of autoimmune thyroiditis in the United States. In our investigations, we have shown directly that T cells from humans with chronic lymphocytic thyroiditis proliferate in the presence of iodinated but not in the presence of noniodinated human thyroglobulin. Moreover, the proliferative response is restored when the thyroglobulin is iodinated artificially in vitro. Using a panel of monoclonal antibodies, we found evidence that the presence of iodine induces a number of stereochemical changes in the conformation of the molecule, resulting in the loss of some antigenic determinants and the appearance of others. One prominent determinant was associated with the iodine-containing amino acid thyroxine. Both the number and position of the iodine substituents determine the precise specificity of this epitope. A new model for the study of the role of iodine in inducing thyroid autoimmunity has become available in the form of the nonobese diabetic (NOD)-H2(h4) mouse. This animal develops autoimmune thyroiditis spontaneously but in relatively low prevalence. However, if iodine is added to the drinking water, the prevalence and severity of the thyroid lesions increase markedly. The immune response is specific for thyroglobulin, both in terms of the antibody response and T-cell proliferation. In fact, the appearance of lesions can be predicted by the presence of thyroglobulin-specific IgG2b antibody. The disease, moreover, can be transferred adoptively, using spleen cells from iodine-fed donors treated in vitro with iodinated thyroglobulin. The effects of iodine feeding are greater in conventional animals compared with those maintained under specific pathogen-free conditions. Based on T-cell proliferation, it appears that the NOD-H2(h4) strain of mice has innately a greater response to murine thyroglobulin than do other mouse strains and that the proliferation is increased even more by feeding iodine. We suggest, therefore, that the presence of iodine increases the autoantigenic potency of thyroglobulin, a major pathogenic antigen in the induction of autoimmune thyroiditis. This animal model provides a unique opportunity for investigating in detail the mechanisms by which an environmental agent can trigger a pathogenic autoimmune response in a susceptible host."
Iodination of human thyroglobulin (Tg) alters its immunoreactivity. II. Fine specificity of a monoclonal antibody that recognizes iodinated Tg.Saboori AM, Rose NR, Burek CL. Clin Exp Immunol. 1998 Aug;113(2):303-8.
"In a previous investigation, we found that murine MoAb 42C3, raised against human Tg, recognized Tg differently depending upon its level of iodination of Tg. A possible explanation for this finding is that iodine is directly involved with the specific epitope recognized by MoAb 42C3. In the present study, we report that the binding of MoAb 42C3 to iodinated Tg is inhibited by T4, T3, reverse T3 (rT3), triiodothyroacetic acid (triac), diiodothyronine (T2), diiodotyrosine (DIT), but not by thyronine (TO) or tyrosine. The order of inhibition of these iodinated compounds is T4 > T3 > rT3 > triac > T2 > DIT. The MoAb 42C3 does not have the same specificity as the T3, T4-receptor since the order of binding of these iodinated compounds on the receptor differed from the order of their inhibition of this MoAb. Monoclonal antibody 42C3 also recognized non-iodinated Tg that was subsequently iodinated in vitro. It failed to recognize another protein, bovine serum albumin, that was iodinated in vitro by the same method. These results suggest that iodinated tyrosines and thyronines determine the binding specificity of MoAb 42C3. The inhibitory effects of these compounds on MoAb 42C3 depend on their iodine content as well as location of iodine in the aromatic ring."
Iodination of human thyroglobulin (Tg) alters its immunoreactivity. I. Iodination alters multiple epitopes of human Tg.Saboori AM, Rose NR, Bresler HS, Vladut-Talor M, Burek CL. Clin Exp Immunol. 1998 Aug;113(2):297-302. "Human Tg, the site of synthesis of thyroid hormones, thyroxine (T4) and triiodothyronine (T3), is one of the major autoantigens in autoimmune thyroiditis. The degree of iodination of Tg may have a major impact on its immunological properties by changing its antigenicity with respect to antibody binding. We have previously prepared a panel of MoAbs that bind to different epitopes of the Tg molecule. In the present study, we show that iodination alters the conformation of Tg molecule in such a way that it is recognized differently by different MoAbs. Monoclonal antibody 137C1 recognizes Tg regardless of its iodine content. Monoclonal antibody 42C3 recognizes Tg only if the Tg is iodinated either in vitro or in vivo. Monoclonal antibody 133B1 recognizes both in vivo iodinated Tg and non-iodinated Tg, but this MoAb did not recognize Tg following in vitro iodination. Monoclonal antibody 41A5 recognizes intact Tg and tryptic peptides of normal (in vivo) iodinated and non-iodinated Tg, but did not bind the tryptic peptides of artificially (in vitro) iodinated Tg. From the results of these experiments, we conclude that iodination of Tg by either in vivo or in vitro methods changes its conformation in such a way that some natural epitopes are 'lost' and some 'new' epitopes are generated. The generation of new epitopes may be important in the generation of autoimmune responses leading to autoimmune disease."
Iodine is essential for human T cell recognition of human thyroglobulin.Rasooly L, Rose NR, Saboori AM, Ladenson PW, Burek CL. Autoimmunity. 1998;27(4):213-9. [abstract only]
"Here we describe for the first time that recognition by human T cells of human thyroglobulin depends upon its iodine content. We have examined the proliferation of lymphocytes from blood of autoimmune thyroiditis patients and normal individuals to thyroglobulin preparations containing different amounts of iodine. A minimal degree of iodination was required to elicit the proliferative response of both patients and normal individuals since thyroglobulin preparations containing no detectable iodine did not induce proliferation. A non-iodinated thyroglobulin preparation that was iodinated in vitro produced significant proliferation of both patient and normal lymphocytes. Addition of IL-2 to the culture medium enhanced proliferation but did not change the pattern of response."
The role of iodine in autoimmune thyroiditis.Rose
NR, Saboori AM, Rasooly L, Burek CL. [abstract only]
"Like most cancers, autoimmune diseases generally are due to the interaction of a number of genetic traits with an environmental trigger. Autoimmune thyroiditis, a model of organ-specific autoimmune disease, is associated with iodine as a precipitating environmental factor. T cells from patients with chronic thyroiditis proliferate in response to normal human thyroglobulin, but fail to react with non-iodinated thyroglobulin. Using a selected monoclonal antibody, we were able to identify a binding site on thyroglobulin containing iodinated thyronine. The greatest affinity was for tetraiodothyronine and binding depended upon the number as well as the positions of iodines. We have also studied an inbred strain of mice, NOD-H2h4, that developed thyroiditis spontaneously. The onset of disease was hastened in a dose-dependent manner by adding iodine to the drinking water. The occurrence of disease was greater in conventional than in specific pathogen-free mice and correlated with T-cell proliferation and IgG2b antibody to thyroglobulin."
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