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Long-term sleep apnea as a pathogenic factor for cell-mediated autoimmune disease.

BACKGROUND: Previous medical literature has shown that cell injury from hypoxia, such as that induced by sleep apnea, leads to hyperuricemia. Furthermore, a recent study has shown that when hyperuricemia reaches sufficient concentration to precipitate as monosodium urate, a T-cell immune response is triggered. The frequent repetition of this cell injury and immune response over a prolonged time, as would occur with long-term sleep apnea, may lead to the development, continuation, or aggravation of autoimmune disease. HYPOTHESIS: Long-term sleep apnea is hypothesized to be a pathogenic factor in the development of cell-mediated autoimmune disease. Several corollaries are presented along with this general hypothesis. First, some of the diseases associated with sleep apnea may have an autoimmune etiology. Second, some autoimmune diseases not usually recognized to be associated with sleep apnea may indeed have that association. Third, resolving sleep apnea in some patients with autoimmune disease to remove that autoimmune stimulus may aid in deceleration, halt, or even reversal of the progress of the autoimmune disease. Fourth, because monosodium urate also causes gouty arthritis in some individuals, diagnosis of gout may allow for resolution of sleep apnea early enough to prevent autoimmune development. Fifth, allopurinol, which suppresses uric acid generation, may be an effective therapy for the remission or prevention of a number of autoimmune diseases. CONCLUSION: This hypothesis strengthens the evidence pointing to the danger of unresolved sleep apnea by a mechanism previously unrecognized, namely the risk of developing an autoimmune disease. As a result of this realization, new therapies may be adopted for the treatment and prevention of autoimmune disease, specifically, resolving sleep apnea and the use of allopurinol.

Autoimmune Diseases↗

Steroid treatment in young MRL.MpJ-Fas(lpr) autoimmune mice prevents cochlear dysfunction.

Corticosteroid therapy reverses clinical autoimmune sensorineural hearing loss, although little is known of how steroids restore normal auditory function. If suppression of systemic autoimmune processes underlies hearing restoration, then preventing autoimmune symptoms from developing should prevent cochlear dysfunction. MRL. MpJ-Fas(lpr) autoimmune mice were used to test this potential mechanism by initiating oral prednisolone treatment at 6 weeks of age, prior to autoimmune disease and hearing loss onset. The steroid treatment group was given prednisolone in their drinking water, while untreated controls were given tap water. Treatment continued for 7 months with periodic evaluations of cochlear function with auditory brainstem response (ABR) audiometry. Autoimmune mice given the steroid lived longer and did not develop levels of serum immune complexes seen in their untreated controls. Also, their ABR thresholds remained near normal throughout the 7 months of treatment, while untreated controls showed progressive threshold elevations typical for autoimmune disease. This correlation of suppressed systemic autoimmune activity and maintenance of normal cochlear function identifies one potential mechanism for autoimmune hearing loss and hearing restoration with steroid therapy. The autoimmune mouse should serve as a valuable model for future studies of the cochlear mechanisms responsive to steroid treatment in autoimmune hearing loss.

Administration, Oral↗

Antilactoferrin antibodies in autoimmune liver disease.

Antilactoferrin antibodies have been reported in patients with several autoimmune disorders, including primary biliary cirrhosis, autoimmune hepatitis and autoimmune cholangitis. We investigated the prevalence and the clinical significance of such autoreactivity in patients with autoimmune and viral chronic liver disease. Sera from 39 patients with autoimmune hepatitis, 51 with primary biliary cirrhosis, 17 with autoimmune cholangitis, 24 with primary sclerosing cholangitis and 28 with HCV-related chronic hepatitis were studied. Positivity for antilactoferrin antibodies was evaluated by Western immunoblotting with purified human lactoferrin. Antilactoferrin antibodies were detected more often in autoimmune liver disorders (25% autoimmune hepatitis, 25% primary biliary cirrhosis, 35% autoimmune cholangitis, 29% primary sclerosing cholangitis) than in HCV-related chronic hepatitis (3.5%, P < 0.02 versus all). Positivity for antilactoferrin antibodies was not associated with a particular clinical or biochemical profile of the underlying liver disease. No correlation was observed between antilactoferrin reactivity and perinuclear antineutrophil cytoplasmic antibodies. Antilactoferrin antibodies are present significantly more often in autoimmune than in viral liver disorders, but they cannot be considered the serological marker of a specific autoimmune liver disease.

Adolescent↗

Effective treatment of autoimmune disease and progressive renal disease by mixed bone-marrow transplantation that establishes a stable mixed chimerism in BXSB recipient mice.

Male BXSB mice spontaneously develop autoimmune disease with features similar to systemic lupus erythematosus. To determine whether this autoimmune disease can be treated as well as prevented by bone-marrow transplantation (BMT) and, at the same time, whether the immunity functions of lethally irradiated recipients can be reconstituted fully, male BXSB mice were engrafted with mixed T cell-depleted marrow (TCDM) both from fully allogeneic autoimmune-resistant BALB/c mice and from syngeneic autoimmune-prone BXSB mice, after the onset of autoimmune disease in the recipient mice. BMT with mixed TCDM from both resistant and susceptible strains of mice (mixed BMT) established stable mixed chimerism, prolonged the median life span, and arrested development of glomerulonephritis in BXSB mice. BMT with mixed TCDM also reduced the formation of anti-DNA antibodies that are observed typically in male mice of this strain. Furthermore, mixed BMT reconstituted the primary antibody production in BXSB recipients impressively. These findings indicate that transplantation of allogeneic autoimmune-resistant TCDM plus syngeneic autoimmune-prone TCDM into lethally irradiated BXSB mice can be used to treat autoimmune and renal disease in this strain of mice. In addition, this dual bone-marrow transplantation reconstitutes the immunity functions and avoids the immunodeficiencies that occur regularly in fully allogeneic chimeras after total body irradiation. This report describes an effective treatment of progressive renal disease and autoimmunity by establishing a stable mixed chimerism of TCDM transplantation from allogeneic autoimmune-resistant BALB/c mice plus syngeneic autoimmune-prone BXSB mice into BXSB mice.

Animals↗

Premature ovarian failure associated with autoimmune polyglandular syndrome: pathophysiological mechanisms and future fertility.

BACKGROUND: Autoimmune polyglandular syndromes (APS) are a series of disorders characterized by autoimmunity against two or more endocrine organs. Premature ovarian failure (POF) may also have an autoimmune origin and, when accompanied by other autoimmune endocrinopathies, may be part of the APSs. Onset of autoimmune ovarian failure usually occurs in childhood, adolescence, or adulthood, and as a result, fertility may be severely compromised. CASE REPORT: A 26-year-old women with secondary amenorrhea, Addison's disease, and autoimmune hypothyroidism requested infertility evaluation. Examination, transvaginal ultrasonography, endocrine evaluation, and ovarian biopsy were performed. 21-Hydroxylase and antithyroid antibodies were demonstrated, but ovarian steroid cell antibodies (StCA) were absent at the time of her infertility evaluation. Transvaginal sonography demonstrated only a few ovarian follicles. An ovarian biopsy revealed lymphocytic infiltration of the ovary. This presentation is consistent with APS type II accompanied by autoimmune POF. DISCUSSION: Unlike APS types I and III, autoimmune POF is more commonly encountered with APS types I and III than with APS type II. An autoimmune response to steroidogenic enzymes and ovarian steroid cells appears to mediate destruction of ovarian function. Although immunotherapy with corticosteroids (with or without in vitro fertilization [IVF]) may be successful in limited cases where several follicles are present, oocyte donation with IVF may be the best option for the patient seeking fertility, particularly in the absence of ovarian follicles. CONCLUSIONS: Advances in molecular genetics may be valuable in predicting and counseling women at risk for APS and POF, and cryopreservation of ovarian tissue may offer hope to affected unmarried young women. It is reasonable to suggest that children and reproductive aged women with one autoimmune disorder should be periodically screened for other autoimmune disorders.

Adult↗

CD4(+) T-cell activation and induction of autoimmune hepatitis following trichloroethylene treatment in MRL+/+ mice.

Exposure to relatively high levels of trichloroethylene has recently been shown to accelerate the development of an autoimmune response in the autoimmune prone MRL+/+ mice. The trichloroethylene-induced autoimmune response was associated with an increase in activated CD4(+) T cells, producing Th(1)-like cytokines. The present study was conducted to determine whether lower, more occupationally relevant doses of trichloroethylene could also promote autoimmunity, in MRL+/+ mice, and if so, to investigate the mechanism of this accelerated autoimmune response. In addition, histological studies were performed to determine if trichloroethylene was capable of producing pathological markers consistent with an autoimmune disease. Trichloroethylene was administered to mice in the drinking water at 0, 0.1, 0.5, and 2.5 mg/ml for 4 and 32 weeks. There was a significant increase above controls in serum antinuclear antibody (ANA) levels following 4 weeks of both 0.1 and 0.5 mg/kg/day of trichloroethylene. After 32 weeks of treatment, ANA levels were elevated and equal in all groups. The kinetics of the ANA response indicated that trichloroethylene accelerated the innate autoimmune response in the MRL+/+ mice. There was a dose-related increase in the percentage of activated CD4(+) T cells in both the spleens and lymph nodes of mice treated for 32 weeks with trichloroethylene when compared to controls. CD4(+) T cells isolated from MRL+/+ mice after either 4 or 32 weeks of treatment with trichloroethylene secreted inflammatory or Th(1)-like cytokines. Following 32 weeks of trichloroethylene treatment, there was a significant increase in hepatic mononuclear infiltration localized to the portal region, a type of hepatic infiltration consistent with autoimmune hepatitis. Taken collectively, these data suggest that exposure to occupationally relevant concentrations of trichloroethylene can accelerate an autoimmune response and can lead to autoimmune disease. The mechanism of this autoimmunity appears to involve, at least in part, activated CD4(+) T cells that then produced inflammatory cytokines.

Animals↗

Helicobacter pylori infection is markedly increased in patients with autoimmune atrophic thyroiditis.

Infection by viral or bacterial pathogens has been suspected in playing a role in the development of autoimmune thyroid disease. Because Helicobacter pylori might be involved in the development of nongastrointestinal conditions such as rosacea, ischemic heart disease, and diabetes mellitus, we evaluated the prevalence of H. pylori infection in patients with autoimmune thyroid disease. Fifty-nine patients with autoimmune thyroid disease were included: autoimmune atrophic thyroiditis (n=21), Hashimoto's thyroiditis (n=18), and Graves' disease (n=20). Twenty patients with nontoxic multinodular goiter served as controls for nonautoimmune thyroid disease, and 11 patients with Addison's disease served as controls for nonthyroid endocrine autoimmune disease. The levels of anti-H. pylori immunoglobulin G (IgG) were determined, and a radiolabeled urea breath test were performed. The prevalence of H. pylori infection was markedly increased in the patients with autoimmune atrophic thyroiditis (85.7%), compared with the controls with nontoxic multinodular goiter (40%) and Addison's disease (45.4%). Infection by H. pylori resulted in increased levels of gastrin, pepsinogen I, and pepsinogen II in the H. pylori-positive groups, compared with the H. pylori-negative groups. A positive linear regression was found between the levels of microsomal autoantibodies and those of anti-H. pylori IgG in patients with autoimmune atrophic thyroiditis (n=21; r=0.79; p < 0.01). Finally, and although the overall prevalence of H. pylori infection was not increased, the anti-H. pylori IgG levels and the results from the breath test were higher in the patients with Graves' disease and Hashimoto's thyroiditis patients than in the controls. Clearly, the prevalence of H. pylori infection is increased in autoimmune atrophic thyroiditis and results in abnormalities of gastric secretory function. The strong relation between the levels of anti-H. pylori IgG and the levels of microsomal antibodies suggests that H. pylori antigens might be involved in the development of autoimmune atrophic thyroiditis or that autoimmune function in autoimmune atrophic thyroiditis may increase the likelihood of H. pylori infection.

Addison Disease↗

Autoimmune mouse antibodies recognize multiple antigens proposed in human immune-mediated hearing loss.

HYPOTHESIS: Autoimmune diseased mice with hearing loss will have autoantibodies against the various cochlear antigens proposed in clinical autoimmune inner ear disease. BACKGROUND: Serum antibodies of patients with hearing loss recognize several proteins that are proposed as possible antigenic targets in the ear. This often leads to a clinical diagnosis of autoimmune inner ear disease, although it is not clear how these antibodies cause inner ear disease. Therefore, to better understand the relationship of autoantibodies and ear disease, an examination was made of serum autoantibodies in the MRL/MpJ-Fas(lpr) autoimmune mouse with hearing loss. Similar antibody patterns in the mouse would provide an animal model in which to investigate potential autoimmune mechanisms of this clinical ear disorder. METHODS: Sera from MRL/MpJ-Fas(lpr) autoimmune mice and normal C3H mice were tested by the enzyme-linked immunosorbent assay technique for reactivity against various reported cochlear antigens: heat shock protein 70 (bovine, human, bacterial), laminin, heparan sulfate proteoglycan, cardiolipin, and collagen types II and IV. RESULTS: The autoimmune mouse sera showed significantly greater antibody reactivity against all of the antigens when compared with normal mouse sera. CONCLUSIONS: Serum antibodies from autoimmune mice recognized several putative autoantigens reported for patients with hearing loss, suggesting that comparable antigen-antibody mechanisms might be operating. However, the recognition of multiple antigens did not identify any one as being the specific target in autoimmune hearing loss. The correlation of antibodies in the MRL/MpJ-Fas(lpr) autoimmune mouse and human studies indicates this animal model should aid further investigations into potential cochlear antigens in autoimmune hearing loss.

Animals↗

Cell Type-Resolved Causal Inference and Spatial Transcriptomic Integration Reveal Immune-Specific Genetic Drivers of Autoimmune and Malignant Thyroid Disease.

BACKGROUND: Thyroid diseases, including autoimmune thyroid disease (AITD) and thyroid cancer, are characterized by immune dysregulation, yet the cell type-specific genetic mechanisms underlying these conditions remain poorly understood. Most genome-wide association studies (GWAS) have relied on bulk tissue expression quantitative trait loci (eQTL), which cannot resolve the heterogeneity of immune cell populations. METHODS: We performed two-sample Mendelian randomization (MR) analyses using single-cell cis-eQTLs from 14 immune cell subtypes (OneK1K cohort) as instrumental variables against GWAS summary statistics for four thyroid outcomes: autoimmune hyperthyroidism, autoimmune hypothyroidism, thyroid cancer and autoimmune thyroiditis. Causal associations were validated through Bayesian colocalization, phenome-wide association analysis (PheWAS) and multi-layered transcriptomic validation encompassing spatial transcriptomics of AITD tissue (GSE248205), bulk RNA-seq of thyroid cancer (GSE3678) and single-cell RNA-seq of thyroid tumours (GSE250521). gsMap spatial LD score regression was applied to map disease heritability onto spatial tissue architecture. RESULTS: We identified six Bonferroni-significant causal gene-cell type pairs for autoimmune hyperthyroidism, including protective effects of ABHD16A in na&#xef;ve/immature B cells (OR&#xa0;=&#xa0;0.440), HIST1H3H in CD8 NC T cells (OR&#xa0;=&#xa0;0.324), HMGN4 in NK recruiting cells (OR&#xa0;=&#xa0;0.556) and ZKSCAN4 in CD8 S100B T cells (OR&#xa0;=&#xa0;0.427), with five pairs showing strong colocalization (PP.H4 &#x2265; 86%). Three pairs reached significance for autoimmune hypothyroidism, including a risk association of HLA-F in CD4 NC T cells (OR&#xa0;=&#xa0;1.139). For autoimmune thyroiditis, FAM134B/RETREG1 showed consistent suggestive protective associations across both CD4 and CD8 NC T cells (PP.H4 &#x2265; 90% for both), suggesting a possible involvement of ER phagy regulation in thyroiditis susceptibility. Thyroid cancer showed a suggestive association with HLA-G in classical monocytes (OR&#xa0;=&#xa0;1.899, PP.H4&#xa0;=&#xa0;53%). Spatial transcriptomic validation demonstrated progressive immune infiltration from control tissue to Graves' disease to Hashimoto's thyroiditis (7.7%-15.7%, 46.1%-54.1%, respectively) and strong spatial correlation between target gene expression and corresponding cell type enrichment (e.g., plasma cell-HLA-DQB1: r&#xa0;=&#xa0;0.491, p < 10-300). HLA-G was independently validated in thyroid cancer bulk (log2fc&#xa0;=&#xa0;0.542, p&#xa0;=&#xa0;9.51&#xa0;&#xd7;&#xa0;10-3, AUC&#xa0;=&#xa0;0.857) and single-cell datasets. PheWAS revealed no significant associations detected for the core candidates. gsMap identified significant enrichment of autoimmune hypothyroidism heritability in gastrointestinal tract, adrenal gland and adipose tissue (all Bonferroni p < 0.002). CONCLUSIONS: This study establishes a multi-scale analytical framework integrating cell type-resolved genetic inference with spatial tissue validation, revealing distinct immunogenetic architectures underlying autoimmune versus malignant thyroid disease. Protective genetic programs in autoimmune hyperthyroidism converge on chromatin remodelling (HIST1H3H, HMGN4, ZKSCAN4) and lipid metabolism (ABHD16A) across lymphocyte subsets, whereas thyroid cancer risk involves immune escape mediated by HLA-G in myeloid cells. The ER-phagy receptor RETREG1 represents a candidate pathway warranting further investigation in autoimmune thyroiditis. These findings provide genetically supported, cell type-specific therapeutic targets and demonstrate a generalizable strategy for dissecting the immune-mediated mechanisms of complex thyroid diseases.

Mendelian randomization↗

Autoimmunity in hepatitis C and D virus infection.

A large number of viruses are capable of inducing acute or chronic hepatitis. The syndrome of chronic hepatitis encompasses not only viral but also autoimmune liver diseases. The hepatitis C virus, and recently also the hepatitis D virus have been found to be associated with an array of autoimmune syndromes, diseases and markers of autoimmunity. The relationship of hepatotropic virus infection and the immune system leading to virus-associated autoimmunity, and its distinction from genuine autoimmune disease represents a fascinating field of research. Clinically, the differentiation between autoimmune liver diseases, virus infection and virus-associated autoimmunity is difficult and epidemiological evaluations have not come up with universally applicable and valid classification criteria. However, both autoimmune liver diseases and viral hepatitis can readily be diagnosed and distinguished through precise and molecularly determined immunological testing systems. The overlap of both, virus-associated autoimmunity, is still at the centre of research activities aimed at establishing diagnostic and risk-assessment criteria. Studies of molecular autoantigens and autoepitopes have begun to define the differences of the B-cell response in autoimmune disease and virus-associated autoimmunity. This provides data that may contribute to the safe application of therapeutic strategies as different as immunosuppression and interferon-alpha (IFN-alpha). The present review focuses on the clinical, epidemiological and molecular aspects of these disease entities.

Animals↗

Cyclosporine-induced autoimmunity and immune hyperreactivity.

Cyclosporine (CS) is a potent immunosuppressive agent which under some circumstances paradoxically augments DTH responses, aggravates some autoimmune diseases, and induces specific forms of autoimmunity. The enhancement of DTH and other immune responses is closely related to the timing of CS administration relative to immunization. CS inhibits IL-2 production (and several other lymphokines) at a pretranscriptional level, but does not usually prevent the antigen-specific priming of T cells, such that T cells may be poised to respond as soon as CS is withdrawn. Thus, accelerated GVHD and allograft rejection may occur after withdrawal of CS. CS has been shown to aggravate and/or induce relapse in several autoimmune diseases including collagen-induced arthritis, EAE, autoimmune thyroiditis, uveitis in SDA chickens, and an autoimmune form of myocarditis in mice. CS may enhance immune responses by inactivating suppressor cells, by altering Th1/Th2 antagonism (e.g., CS promotes a protective Th1-type response in BALB/c mice infected with Leishmania major), or by promoting T cell activation through a CS-resistant IL-2-independent T cell activation/differentiation pathway. At least three forms of CS-induced autoimmunity have been described: Syngeneic or autologous GVHD which occurs in CS-treated syngeneic or autologous bone marrow transplant recipients after CS is withdrawn in rats, mice, and humans; a systemic autoimmune disease with polyarthritis and glomerulonephritis which occurs in irradiated CBA/N mice treated with CS; and organ-specific autoimmune diseases which occur in mice treated with CS during the neonatal period. The precise mechanisms by which CS induces these autoimmune diseases are not clear, however, CS affects immune tolerance at three levels. CS induces thymic medullary involution with loss of medullary Ia+ cells, and appears to at least partially block the transition from double positive (CD4+CD8+) to single positive (mature type) thymocytes. In syngeneic bone marrow chimeras, CS appears to inhibit the intrathymic deletion of clones with relatively low affinity, but not those with high affinity, to self antigens. CS appears to inhibit the action of suppressor T cells which normally maintain an innate form of resistance to autoimmunity. Finally, CS has been shown to prevent the development of T cell clonal anergy. There is redundancy in immune tolerance mechanisms, i.e., clonal deletion, clonal anergy, and suppressor cells can each maintain tolerance to similar antigens, such that it is likely that CS must cripple more than one tolerance mechanism for autoimmunity to occur.

Adjuvants, Immunologic↗

The tumor necrosis factor beta * 1 allele is linked significantly to HLA-DR8 in Koreans with atrophic autoimmune thyroiditis who are positive for thyrotropin receptor blocking antibody.

The localization and functional characteristics of tumor necrosis factor(TNF) beta gene raise the possibility that it may be involved in the susceptibility to autoimmune thyroid diseases. To investigate whether a TNF beta gene polymorphism is associated with autoimmune thyroiditis, we analyzed the TNF beta gene polymorphism with the restriction enzyme NcoI in 48 Korean patients with atrophic autoimmune thyroiditis [23 were found to be thyrotropin binding inhibitor immunoglobulin(TBII) positive, 25 TBII negative], 52 goitrous autoimmune thyroiditis, and 129 healthy controls. Two TNF beta alleles were identified from the restriction fragment length polymorphism studies of amplified genomic DNA. In atrophic autoimmune thyroiditis patients positive for TBII, 7 of 23 patients were homozygous for the TNF beta * 1 allele, 3 were homozygous for the TNF beta * 2 allele, and 13 were TNF beta * 1/2 heterozygous compared to controls(P = 0.20). Also, there were no associations between the TNF beta gene polymorphism and either TBII-negative atrophic autoimmune thyroiditis or goitrous autoimmune thyroiditis. Of the HLA-class II antigens, the frequency of HLA-DR8 was significantly greater among the 23 Korean patients with TBII-positive atrophic autoimmune thyroiditis compared to control subjects (Pc = 0.003). When the HLA-DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis and controls were analyzed separately, the DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis had more homozygotes for the TNF beta * 1 allele(6/12, 50.0%) and no homozygotes for the TNF beta * 2 allele, as compared to the DR8 negative patients with TBII-positive atrophic autoimmune thyroiditis and DR8 positive controls(P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗

Role of autoimmunity in nonviral chronic liver disease.

OBJECTIVE: To evaluate the prevalence and clinical profile of autoimmune hepatitis (AIH) in patients with chronic liver disease. METHODS: Four hundred and thirty five consecutive patient with chronic liver disease seen in our department from January 1997 to December 1998 were studied with detailed history and clinical examination. All the patients underwent liver function tests, ultrasonography, isotope liver scanning, viral markers, autoimmune markers ANA, ASMA, LKM1 and AMA (by immunofluorescence technique) and liver histology whenever permissible. Appropriate work up for Wilson's disease was done whenever suspected clinically. Diagnosis of autoimmune hepatitis was made by the composite scoring system by international autoimmune hepatitis group. Twenty out of the 435 patients met the criteria of definite autoimmune hepatitis and seven patient had probable autoimmune hepatitis. Forty out of 408 patients showed markers of autoimmunity positive but did not qualify diagnosis of AIH on composite scores. RESULTS: Demographic profile of 27 patients with autoimmune hepatitis was as follows; male:female ratio 1:8, mean age 39.8 +/- 13 years (Range 4-65 years); mode of presentation as cirrhosis 11/27 (40.7%), chronic hepatitis 12/27 (44.4%) and acute hepatitis 4/27 (14.8%). Elevated serum bilirubin levels were seen in 12 (44.4%) patients while mean serum aminotransferases levels were 249 +/- 343 and 262 +/- 418 respectively. Other disease associations seen were as follows: diabetes in 4 (14.8%), rheumatoid arthritis in 3 (11%), hypothyroidism in 2 (7.4%) and ulcerative colitis in 1 (3.7%). The pattern of autoimmune markers was ANA +ve 23/27 (85%) (+ve titres of ANA > 1:80 in adults and 1:20 in children), ASMA +ve in 16/27 (59.2%) (+ve titres of ASMA > 1:40) and LKM1 in 3 patients. AMA in tires less than 1:80 was found in 3 patients. Liver histology changes seen were lymphoplasmacytic infiltrates (100%), bridging necrosis (93%), liver cell rossetting (80%) and fibrosis with or without cirrhosis (50%). CONCLUSION: Autoimmune liver disease is not uncommon in India and should be suspected in all patients with chronic liver disease, especially in non-viral, non-alcoholic, female patients. The diagnosis of AIH should however be made on the composite scoring system given by international group and not only on the presence or absence of autoimmune markers.

Adolescent↗

Clinical characteristics and mycology of onychomycosis in autoimmune patients.

Onychomycosis is the most common nail disorder in adults. Predisposing factors are immunosuppression, poor peripheral circulation, diabetes mellitus, increasing age, nail trauma, and tinea pedis. Autoimmune patients, who carry many of these predisposing factors, have never been studied. Autoimmune patients, with underlying autoimmune skin diseases; pemphigus, systemic lupus erythematosus (SLE), mixed connective tissue disease (MCTD), scleroderma, dermatomyositis and cutaneous vasculitis, as well as having abnormal-appearing nail(s) with suspicion of fungal nail infection were included. Clinical information was obtained. The causative organisms were identified by potassium hydroxide preparation and cultured. Duration of onychomycosis in autoimmune patients was twice longer than in non-autoimmune patients. Of those with mycological proven onychomycosis, the autoimmune patients had significantly more affected nails (p < 0.05; chi2, two-sided) compared to the non-autoimmune patients but there was no difference in the affected fingernails or toenails and clinical type of onychomycosis. Candida spp was the most frequently found in autoimmune subjects compared to dermatophytes, Trichophyton rubrum. However, dermatophytes especially Trichophyton rubrum was the most common causative organism in non-autoimmune samples, followed by Candida spp. The causative organisms were more frequently discovered in autoimmune patients, whether by potassium hydroxide (KOH) or culture, than in non-autoimmune patients (p < 0.05; chi2, two-sided).

Adult↗

Hepatitis C virus infection and autoimmune thrombocytopenic purpura.

BACKGROUND/AIMS: Chronic hepatitis C virus infections are often associated with extra-hepatic immunological manifestations, including various autoimmune disorders. The aims of this study were: (i) to determine the prevalence of hepatitis C virus markers in patients with autoimmune thrombocytopenic purpura, and (ii) to determine whether a relationship could exist between autoimmune thrombocytopenic purpura and hepatitis C virus infections. METHODS: One hundred and thirty-nine patients with autoimmune thrombocytopenic purpura (45 men, 94 women, mean age 42 years, range 16-90) were studied. RESULTS: Anti-HCV antibodies were sought in their first and last available cryopreserved sera. In case of seropositivity, all their available cryopreserved sera were tested for anti-HCV antibodies and for HCV-RNA. Anti-HCV antibodies were detected in 14 of the 139 patients (10%). Four patients had transient anti-HCV seropositivity due to passive transfer of anti-HCV antibodies secondary to the infusion of intravenous immunoglobulin concentrates. Three patients seroconverted during follow up, due to intravenous drug use in one case, transfusion of non-HCV-screened blood units in one case, and infusion of intravenous immunoglobulins in one case. Seven patients had chronic hepatitis C discovered at the same time as autoimmune thrombocytopenic purpura. In two of them, hepatitis C virus transmission was the consequence of autoimmune thrombocytopenic purpura treatment but, in five cases, hepatitis C virus infection predated autoimmune thrombocytopenic purpura, so that the role of hepatitis C virus in autoimmune thrombocytopenic purpura could be suggested. CONCLUSIONS: Whereas hepatitis C virus does not appear to be the main etiological agent of autoimmune thrombocytopenic purpura can be envisaged. On the other hand, treatment of autoimmune thrombocytopenic purpura or autoimmune thrombocytopenic purpura-related symptoms by blood product infusion can be complicated by hepatitis C virus transmission.

Adolescent↗

The forces driving autoimmune disease.

There are two classes of autoimmune disease, organ-specific and non-organ specific or systemic. That cells producing autoantibodies are selected by antigen is strongly suggested by the presence of mutations and high affinity antibody. T-cells are pivotal in all forms of autoimmunity as evidenced by the therapeutic benefit of anti-T-cell monoclonals such as anti-CD4, and the frequent development of high affinity IgG autoantibodies. The production of anergic T-cells by the use of non-depleting anti-CD4 in the presence of antigen is discussed with particular reference to its potential for immunological intervention in autoimmune disease. It is possible to identify T-cell epitopes in organ-specific autoimmunity using pathogenic T-cell clones or hybridomas to identify the peptide sequences which are reactive. Antigen-specific therapy may ultimately be based on such peptide epitopes. The specificity of the T-cells in systemic autoimmunity is still obscure, but there is some evidence that reactivity with certain germ-line idiotypes can lead to the development of systemic autoimmunity. The possibility of stimulating B-cells specific for auto-antigens such as DNA becomes feasible if a complex of antibody and DNA is taken up by these specific B-cells and processed idiotype is presented to T-helpers specific for those idiotype epitopes. Evidence is presented that there may be pre-existing defects in the target organ in certain organ-specific disorders, and the evidence for a glycosylation defect in the IgG in patients with rheumatoid arthritis is explored. It is noted that the spouses of probands with rheumatoid arthritis is explored. It is noted that the spouses of probands with rheumatoid arthritis also tend to have this glycosylation defect and this raises the possibility of an effect due to an environmental factor, such as a microbial infection. Molecular mimicry of autoantigens by microbes can stimulate autoreactive cells by their cross-reactivity. It is emphasized that cross-reaction which gives rise to the priming of autoreactive T-cells could give rise to the establishment of a chronic autoimmune state. In animals with normal regulatory immune systems, such induced autoimmunity is ultimately corrected and it is only in animals where there are defects in regulation, that autoimmunity persists. Thus, there are many factors giving rise to autoimmunity, and the diseases are rightly regarded as multifactorial in origin.

Amino Acid Sequence↗

Overlap syndromes in the context of shared autoimmunity.

The presence of autoimmune rheumatic diseases in several members of the same family, the concurrence of autoimmune rheumatic with non-rheumatic diseases in relatives of patients, the presence of autoantibodies in sera from healthy relatives of autoimmune-disease patients, the development of two or more autoimmune rheumatic diseases in one patient and the interplay of genetic and environmental factors leading to the presence of several autoimmune disease and/or their autoantibodies in families, is being termed "shared autoimmunity". Herein we analyzed autoimmune rheumatic overlap syndromes in this context. We performed a retrospective analysis of the clinical, serological and radiological characteristics of patients with overlap syndromes from the Clinic of Rheumatic Diseases at the Department of Immunology and Rheumatology of the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán. We found 23 patients with overlap syndromes; 13 patients with rhupus, 5 with sclerodermatomyositis, 3 with scleroderma and SLE, one with sclerodermatomyositis and SLE and one with scleroderma and MPA. Rhupus tends to develop sequentially while sclerodermatomyositis tends to appear simultaneously. The other overlap syndromes are less common and their clinical course is rather aggressive, although clinical manifestations respond to standard treatment. The second and/or third disease appears while the first one is still active, even with adequate treatment. The coexistence of autoimmune rheumatic diseases may be partially explained by the interplay of environmental factors with genes that predispose to autoimmunity in general and to manifestations of specific diseases. This is part of the concept of Shared Autoimmunity.

Adult↗

Gene defect behind APECED: a new clue to autoimmunity.

The molecular background of human autoimmunity is poorly understood. Although many autoimmune diseases have a genetic basis, the actual disease appearance results from a complex interplay between genes and environment and thus these diseases represent typical multifactorial diseases. Even with molecular tools provided by the Human Genome Project, it still remains a challenge to identify the predisposing DNA variants behind such multifactorial traits. Two strategies have been suggested to provide short-cuts to the dissection of the genetic background of complex autoimmune diseases: (i) identification of genes in rare human diseases with a strong autoimmune component or (ii) unravelling loci causing phenotypes resembling autoimmune diseases in inbred mice strains. Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a monogenic autosomal disease with a recessive inheritance pattern, characterized by multiple autoimmune endocrinopathies, chronic mucocutaneous candidiasis and ectodermal dystrophies. Since it is the only known human autoimmune disease inherited in a Mendelian fashion, it provides an excellent model to analyse the genetic component of human autoimmunity. The causative gene for APECED was isolated recently by a traditional positional cloning strategy by two independent groups. The cDNA for the APECED gene proved to originate from a novel gene, AIRE , which is expressed prevalently in thymus, pancreas and adrenal cortex. Multiple mutations in AIRE have been identified in APECED patients. The predicted proline-rich AIRE polypeptide harbours two PHD-type zinc finger motifs and contains a putative nuclear targeting signal suggesting its involvement in the regulation of transcription. In the future, functional analysis of the AIRE protein both in vitro and in vivo will provide valuable insight not only into the molecular pathogenesis of APECED but also into the aetiology of autoimmunity in general.

Animals↗