Genome wide identification of new genes and pathways in patients with both autoimmune thyroiditis and type 1 diabetes

Autoimmune thyroid diseases (AITD) and Type 1 diabetes (T1D) frequently occur in the same individual pointing to a strong shared genetic susceptibility. Indeed, the co-occurrence of T1D and AITD in the same individual is classified as a variant of the autoimmune polyglandular syndrome type 3 (designated APS3v). Our aim was to identify new genes and mechanisms causing the co-occurrence of T1D + AITD (APS3v) in the same individual using a genome-wide approach. For our discovery set we analyzed 346 Caucasian APS3v patients and 727 gender and ethnicity matched healthy controls. Genotyping was performed using the Illumina Human660W-Quad.v1. The replication set included 185 APS3v patients and 340 controls. Association analyses were performed using the PLINK program, and pathway analyses were performed using the MAGENTA software. We identified multiple signals within the HLA region and conditioning studies suggested that a few of them contributed independently to the strong association of the HLA locus with APS3v. Outside the HLA region, variants in GPR103, a gene not suggested by previous studies of APS3v, T1D, or AITD, showed genome-wide significance (p < 5 × 10⁻⁸). In addition, a locus on 1p13 containing the PTPN22 gene showed genome-wide significant associations. Pathway analysis demonstrated that cell cycle, B-cell development, CD40, and CTLA-4 signaling were the major pathways contributing to the pathogenesis of APS3v. These findings suggest that complex mechanisms involving T-cell and B-cell pathways are involved in the strong genetic association between AITD and T1D.     

Lack of ceramide synthase 2 suppresses the development of experimental autoimmune encephalomyelitis by impairing the migratory capacity of neutrophils

Ceramide synthases (CerS) synthesise ceramides of defined acyl chain lengths, which are thought to mediate cellular processes in a chain length-dependent manner. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), we observed a significant elevation of CerS2 and its products, C24-ceramides, in CD11b⁺ cells (monocytes and neutrophils) isolated from blood. This result correlates with the clinical finding that CerS2 mRNA expression and C24-ceramide levels were significantly increased by 2.2- and 1.5-fold, respectively, in white blood cells of MS patients. The increased CerS2 mRNA/C24-ceramide expression in neutrophils/monocytes seems to mediate pro-inflammatory effects, since a specific genetic deletion of CerS2 in blood cells or a total genetic deletion of CerS2 significantly delayed the onset of clinical symptoms, due to a reduced infiltration of immune cells, in particular neutrophils, into the central nervous system. CXCR2 chemokine receptors, expressed on neutrophils, promote the migration of neutrophils into the central nervous system, which is a prerequisite for the recruitment of further immune cells and the inflammatory process that leads to the development of MS. Interestingly, neutrophils isolated from CerS2 null EAE mice, as opposed to WT EAE mice, were characterised by significantly lower CXCR2 receptor mRNA expression resulting in their reduced migratory capacity towards CXCL2. Most importantly, G-CSF-induced CXCR2 expression was significantly reduced in CerS2 null neutrophils and their migratory capacity was significantly impaired. In conclusion, our data strongly indicate that G-CSF-induced CXCR2 expression is regulated in a CerS2-dependent manner and that CerS2 thereby promotes the migration of neutrophils, thus, contributing to inflammation and the development of EAE and MS.     

2例胰岛素自身免疫综合征临床病例分析

通过回顾分析我院2例确诊为胰岛素自身免疫综合征(IAS)患者的临床资料,并复习相关文献,总结发病机制及治疗方法,探讨IAS患者的临床特点,提高对低血糖症的诊治水平。     

Aminotransferases During Treatment Predict Long-Term Survival in Patients With Autoimmune Hepatitis Type 1: A Landmark Analysis

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甲状腺乳头状癌伴发桥本甲状腺炎的临床研究

背景与目的：甲状腺乳头状癌（papillary thyroid carcinoma，PTC）和桥本甲状腺炎（Hashimoto’s thyroiditis，HT）的发病率均呈上升趋势，两者之间的关系已成为目前研究的热点。探讨PTC和HT之间的关系。方法：回顾性分析2014—2015年期间在中国科学院大学附属肿瘤医院头颈肿瘤外科行甲状腺癌手术治疗的首诊患者306例，术后病理学检查均明确诊断为PTC，其中术后病理学确诊伴发HT者42例，比较伴发HT与未伴发HT患者的临床病理学特征。结果：PTC患者女性发病年龄高于男性（46.2岁 vs 41.9岁）。相较于与未伴发HT的PTC患者，伴发HT的患者中女性比例更高（93% vs77%），中央区淋巴结数目较多［（5.0±3.4）枚 vs （2.5±2.7）枚］，术前促甲状腺激素（thyroid-stimulating hormone，TSH）水平较高［（3.28±1.91）μU/mL vs （2.12±1.29）μU/mL］，术前抗甲状腺过氧化物酶抗体（thyroid peroxidaseantibody，TPOAb）阳性率较高（55% vs 14%），术前甲状腺球蛋白抗体（thyroglobulin antibodies，TgAb）阳性率较高（69% vs 13%）。发生中央区淋巴结转移的患者中，中央区淋巴结转移数目与中央区淋巴结总数显著相关（Pearson相关系数=0.582）。多因素logistic回归分析发现，男性、低龄、被膜侵犯是PTC患者中央区淋巴结转移的独立危险因素。结论：伴发HT对PTC患者的预后无显著影响。伴发HT的PTC患者TSH水平显著偏高，提示HT可能是PTC发病风险因素之一。中央区淋巴结转移数目与中央区淋巴结总数相关，推测PTC淋巴结转移可能与淋巴结炎症反应相关。