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1.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
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Allergic autoimmune reaction after exposure to heavy metals such as mercury may play a causal role in autism, a developmental disorder of the central nervous system. As metallothionein (MT) is the primary metal-detoxifying protein in the body, we conducted a study of the MT protein and antibodies to metallothionein (anti-MT) in normal and autistic children whose exposure to mercury was only from thimerosal-containing vaccines. Laboratory analysis by immunoassays revealed that the serum level of MT did not significantly differ between normal and autistic children. Furthermore, autistic children harboured normal levels of anti-MT, including antibodies to isoform MT-I (anti-MT-I) and MT-II (anti-MT-II), without any significant difference between normal and autistic children. Our findings indicate that because autistic children have a normal profile of MT and anti-MT, the mercury-induced autoimmunity to MT may not be implicated in the pathogenesis of autism.  相似文献   
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Aims The Type 1 diabetes susceptibility locus, IDDM2, has been mapped to a variable number of tandem repeats (VNTR) region 5′ upstream of the insulin (INS) and insulin‐like growth factor (IGF2) genes on chromosome 11p15. The function of the VNTR is uncertain; however, it may influence the thymic expression of the insulin gene and affect the development of immune self‐tolerance. The aim of this study was to investigate whether the INS VNTR region is a Type 1 diabetes‐specific locus or acting as a general autoimmunity gene. Methods We genotyped the INS‐IGF2 VNTR [using the surrogate INS?23 HphI single nucleotide polymorphism (SNP)] in 823 Graves’ disease (GD)/multiple sclerosis (MS) families, 1433 GD/MS patients and 837 healthy control subjects. Results We found no evidence of excess transmission of the allele associated with Type 1 diabetes to individuals affected by GD or MS within the families. Analysis of the case–control dataset showed no genotypic or allelic difference between the two populations. Conclusions These data suggest that the INS‐IGF2 VNTR is acting as a Type 1 diabetes‐specific susceptibility gene rather than as an influence on general autoimmunity.  相似文献   
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目的 研究子宫内膜异位症(内异症)患者在位和异位子宫内膜人白细胞抗原HLA—DR的表达。方法 采用酶标链霉亲合素—生物素(LSAB)技术对19例内异症不孕患者在位和异位子宫内膜腺细胞HLA—DR抗原的表达进行免疫组化研究,以19例非子宫内膜异位症的不孕患者作为对照。结果 内异症患者在位和异位子宫内膜腺细胞HLA—DR抗原的表达较对照组明显增强(P<0.01)。结论 子宫内膜HLA—DR抗原的异常表达可能参与了内异症免疫学异常的发生。  相似文献   
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The aim of the study was to determine the prevalence of thyroid autoimmune disorders in a cohort of untreated multiple sclerosis (MS) patients and compare it with a stratified sample of an adult population. We prospectively studied 93 untreated MS patients. The control group included 401 healthy subjects selected by stratified sampling in a non-iodine-deficient area. Antithyroid antibodies (ATA) (antibodies against peroxidase and thyroglobulin) were considered positive at titres ≥149 IU/ml. Antibodies were positive in 11 MS patients (11.8%; 95% CI 5.3–18.4%). This prevalence was five times higher ( P  = 0.0001) when compared with that in the control population. We found six cases with subclinical hypothyroidism (6.45%; 95% CI 11.4–1.5) in contrast to 2.24% in the control group. Comparing MS with positive and negative ATA, there was a non-significant, slightly higher frequency of low Expanded Disability Status Scale (EDSS) score in the ATA-positive group (81% vs. 73.2%). One year after start of interferon (IFN) treatment, only one patient developed subclinical thyroid dysfunction. MS patients have a higher prevalence of ATA compared with the general population. An initial ATA and thyroid-stimulating hormone (TSH) determination is recommended in all MS patients. A periodic assessment of thyroid function during IFN treatment only seems to be justified in those cases where positive ATA or dysfunction is present before treatment.  相似文献   
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The paraneoplastic autoantibody, collapsin response-mediator protein (CRMP)-5 immunoglobulin G (IgG), is specific for neuronal cytoplasmic CRMP-5, and is usually associated with small-cell lung carcinoma or thymoma. We report on details of a movement disorder that followed anti-B-cell therapy in a patient with lymphoma, and was accompanied by CRMP-5 IgG.  相似文献   
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The protective effect of affinity purified antigen has been investigated in an experimental model for malaria which shows a well marked recrudescence of parasitaemia, a feature of the disease in man. A monoclonal antibody (MoAb) recognizing an epitope common to two genetically distinct cloned lines of Plasmodium chabaudi (AS and CB), was used to purify a Mr250,000 polymorphic schizont antigen (PSA) from these parasites. The purified preparations were then examined for the presence of specific and cross-reactive epitopes by immunoprecipitation with a panel of MoAb raised against P. chabaudi AS. When tested previously on smears of parasitized blood by immunofluorescence, or against lysates of parasitized erythrocytes by immunoprecipitation, most of these MoAb had been found to be AS specific. When either AS or CB affinity purified Mr250,000 PSA was used as the target, these same MoAb immunoprecipitated both antigens, and in some cases, a number of associated polypeptides (AP) which copurify with the Mr250,000 PSA. Subsequently, mice were immunized with either the purified AS or CB antigens in Freund's complete adjuvant (FCA). Prechallenge sera were compared by indirect immunofluorescence and immunoprecipitation. Sera from mice immunized with AS antigen reacted strongly with AS and cross-reacted with CB parasite preparations. Pre-challenge serum from CB antigen immunized mice reacted well with CB, but only faintly with AS preparations. In mice immunized with the AS antigen and then challenged with either AS or CB parasites, the initial parasitaemias were delayed in appearance and the height of the peak parasitaemia reduced, an effect which was most pronounced after challenge with homologous parasites. Only homologous challenge of the mice immunized with CB antigen produced statistically significant modification of the initial parasitaemia. In the immunized mice challenged with homologous parasites, the delayed appearance and slightly reduced peak of the primary parasitaemia was associated with delayed resolution of the patent parasitaemia and significant enhancement of the recrudescence.  相似文献   
10.
Exacerbation of myasthenia gravis after removal of thymomas   总被引:6,自引:0,他引:6  
It appeared from this prospective and non-randomized study, that the removal of thymomas in myasthenia gravis (MG) patients resulted in rapid exacerbation of the clinical severity of the disease and of anti-acetylcholine receptor antibodies titres, which peaked after about 300 days and continued for up to 2 years. Long-term follow-up after thymomectomy (mean duration ± SEM after surgery 5.5 ± 0.8 years) showed that the immunological and clinical state observed prior to surgery was eventually restored, but long-term benefit attributable to surgery could not be demonstrated. Non-thymoma MG cases, however, exhibited post-operative amelioration in clinical course and decreasing antibodies titres, both of which were already significant one year after surgery, and additional improvement was observed at the time of long-term follow-up (mean 4.3 ± 0.5 years). Furthermore, the prognosis for MG patients not operated on was also favourable. It is suggested that the occurrence of thymomas is linked to genetic factors and that neoplasia of the thymus may be part of immunoregulatory mechanisms with predominance of inhibition.  相似文献   
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