Coincident diabetes mellitus modulates Th1‐, Th2‐, and Th17‐cell responses in latent tuberculosis in an IL‐10‐ and TGF‐β‐dependent manner

Type 2 diabetes mellitus (DM) is a risk factor for the development of active tuberculosis (TB), although its role in the TB‐induced responses in latent TB (LTB) is not well understood. Since Th1, Th2, and Th17 responses are important in immunity to LTB, we postulated that coincident DM could alter the function of these CD4⁺ T‐cell subsets. To this end, we examined mycobacteria‐induced immune responses in the whole blood of individuals with LTB‐DM and compared them with responses of individuals without DM (LTB‐NDM). T‐cell responses from LTB‐DM are characterized by diminished frequencies of mono‐ and dual‐functional CD4⁺ Th1, Th2, and Th17 cells at baseline and following stimulation with mycobacterial antigens‐purified protein derivative, early secreted antigen‐6, and culture filtrate protein‐10. This modulation was at least partially dependent on IL‐10 and TGF‐β, since neutralization of either cytokine resulted in significantly increased frequencies of Th1 and Th2 cells but not Th17 cells in LTB‐DM but not LTB individuals. LTB‐DM is therefore characterized by diminished frequencies of Th1, Th2, and Th17 cells, indicating that DM alters the immune response in latent TB leading to a suboptimal induction of protective CD4⁺ T‐cell responses, thereby providing a potential mechanism for increased susceptibility to active disease.     

TGF‐β induces the differentiation of human CXCL13‐producing CD4+ T cells

In the ectopic lymphoid‐like structures present in chronic inflammatory conditions such as rheumatoid arthritis, a subset of human effector memory CD4⁺ T cells that lacks features of follicular helper T (Tfh) cells produces CXCL13. Here, we report that TGF‐β induces the differentiation of human CXCL13‐producing CD4⁺ T cells from naïve CD4⁺ T cells. The TGF‐β‐induced CXCL13‐producing CD4⁺ T cells do not express CXCR5, B‐cell lymphoma 6 (BCL6), and other Tfh‐cell markers. Furthermore, expression levels of CD25 (IL‐2Rα) in CXCL13‐producing CD4⁺ T cells are significantly lower than those in FoxP3⁺ in vitro induced Treg cells. Consistent with this, neutralization of IL‐2 and knockdown of STAT5 clearly upregulate CXCL13 production by CD4⁺ T cells, while downregulating the expression of FoxP3. Furthermore, overexpression of FoxP3 in naïve CD4⁺ T cells downregulates CXCL13 production, and knockdown of FoxP3 fails to inhibit the differentiation of CXCL13‐producing CD4⁺ T cells. As reported in rheumatoid arthritis, proinflammatory cytokines enhance secondary CXCL13 production from reactivated CXCL13‐producing CD4⁺ T cells. Our findings demonstrate that CXCL13‐producing CD4⁺ T cells lacking Tfh‐cell features differentiate via TGF‐β signaling but not via FoxP3, and exert their function in IL‐2‐limited but TGF‐β‐rich and proinflammatory cytokine‐rich inflammatory conditions.     

小热休克蛋白22基因在腓骨肌萎缩症中的突变分析

目的 探讨小热休克蛋白22（small heat-shock protein 22，HSP22）基因在中国人腓骨肌萎缩症（Charcot-Marie-Tooth disease，CMT）中的突变特点。方法 应用聚合酶链反应和DNA直接测序方法，对1个发现HSP22基因423（G→T）突变的CMT2L家系外的114个CMT家系先证者进行了且HSP22基因的突变分析。结果 114个先证者中有2例患者在且HSP22基因的第3外显子发生了582（C→T）碱基改变，由于编码的氨基酸未改变，均为色氨酸（Thr），为一种同义突变。结论 HSP22基因突变在中国人的腓骨肌萎缩症患者中少见，突变率为0.87％（1／115）。     

真核表达4-1BBL调节淋巴细胞功能活性及抗肿瘤效应的研究

目的：在非免疫非肿瘤细胞中转染表达4-1BBL，并研究4-1BBL在调节淋巴细胞功能活性及抗肿瘤方面的作用和机制。方法：构建含有4-1BBL全长eDNA序列的表达质粒p4-1BBL，脂质体介导体外转染BHK细胞，G418筛选出阳性克隆，RT-PCR、免疫细胞化学染色及免疫印迹检测4-1BBL的表达，检测BHK细胞表达的4-1BBL对脾淋巴细胞增殖和杀伤活性的影响；建立小鼠H22肝细胞癌移植瘤模型，裸DNA肌肉注射法体内转染表达4-1BBL进行肿瘤治疗，检测肿瘤生长速度；另外，利用免疫组化染色法分析瘤周组织中CD8^＋T淋巴细胞。结果：BHK细胞转染表达的4-1BBL能够显著增强肿瘤抗原肽激活的脾淋巴细胞增殖和杀瘤活性（P〈0．01），并显著提高IL-2和IFN-γ表达水平（P〈0．01），同时增强非特异性免疫杀伤活性。肿瘤接种部位转染表达4-1BBL，瘤周组织中CD8^＋T淋巴细胞数量显著增加（P〈0．01），肿瘤生长速率显著低于生理盐水对照组和空载体对照组（P〈0．01）。结论：在肿瘤微环境中的正常细胞转染表达4-1BBL，能够有效促进T细胞增殖及杀伤等功能活性，可望成为肿瘤免疫生物治疗的一种新的手段。     

Oxidative Stress Produced with Cell Migration Increases Synthetic Phenotype of Vascular Smooth Muscle Cells

Phenotypic modulation of vascular smooth muscle cells (VSMC) and reactive oxygen species (ROS) is important in vascular pathogenesis. Understanding how these factors relate to cell migration can improve design of therapeutic interventions to control vascular disease. We compared the proliferation, protein content and migration of cultured aortic VSMC from wild type (WT) versus transgenic mice (Tg^p22phox), in which overexpression of p22phox was targeted to VSMC. Also, we compared H₂O₂ generation and expression of specific phenotypic markers of non-migrating with migrating WT versus Tg^p22phox VSMC in an in vitro wound scratch model. Enhanced H₂O₂ production in Tg^p22phox versus WT VSMC (p < 0.005) significantly correlated with increased protein content, proliferation, and migration. VSMC migrating across the wound edge produced more H₂O₂ than non-migrating VSMC (p < 0.05). The expression of synthetic phenotypic markers, tropomyosin 4 and myosin heavy chain embryonic (SMemb), was enhanced significantly, while the expression of contractile marker, smooth muscle α-actin, was reduced significantly in migrating versus non-migrating cells, and also in Tg^p22phox versus WT (p < 0.005) VSMC. These results are consistent with increased production of ROS accelerating the switch from the contractile to the synthetic phenotype, characterized by increases in proliferation, migration, and expression of TM4 and SMemb and decreased α-actin.     

染色体平衡易位t(11;22)携带者一例三次妊娠分析

目的探讨t(11;22)平衡易位携带者对子代的影响.方法对1例t(11;22)平衡易位携带者的三孕进行分析.结果第1、3孕均分娩了额外der(22) t(11;22) 综合征患儿,第2孕胎儿脐血染色体检查提示为平衡易位携带者.结论平衡易位携带者在妊娠时应做产前检查,以防异常胎儿的出生.     

Vitamin D downregulates the IL-23 receptor pathway in human mucosal group 3 innate lymphoid cells

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Protein tyrosine phosphatase PTPN22 regulates IL‐1β dependent Th17 responses by modulating dectin‐1 signaling in mice

A single nucleotide polymorphism within the PTPN22 gene is a strong genetic risk factor predisposing to the development of multiple autoimmune diseases. PTPN22 regulates Syk and Src family kinases downstream of immuno‐receptors. Fungal β‐glucan receptor dectin‐1 signals via Syk, and dectin‐1 stimulation induces arthritis in mouse models. We investigated whether PTPN22 regulates dectin‐1 dependent immune responses. Bone marrow derived dendritic cells (BMDCs) generated from C57BL/6 wild type (WT) and Ptpn22^?/? mutant mice, were pulsed with OVA_323‐339 and the dectin‐1 agonist curdlan and co‐cultured in vitro with OT‐II T‐cells or adoptively transferred into OT‐II mice, and T‐cell responses were determined by immunoassay. Dectin‐1 activated Ptpn22^?/? BMDCs enhanced T‐cell secretion of IL‐17 in vitro and in vivo in an IL‐1β dependent manner. Immunoblotting revealed that compared to WT, dectin‐1 activated Ptpn22^?/? BMDCs displayed enhanced Syk and Erk phosphorylation. Dectin‐1 activation of BMDCs expressing Ptpn22^R619W (the mouse orthologue of human PTPN22^R620W) also resulted in increased IL‐1β secretion and T‐cell dependent IL‐17 responses, indicating that in the context of dectin‐1 Ptpn22^R619W operates as a loss‐of‐function variant. These findings highlight PTPN22 as a novel regulator of dectin‐1 signals, providing a link between genetically conferred perturbations of innate receptor signaling and the risk of autoimmune disease.     

TGFβ pathway deregulation and abnormal phospho‐SMAD2/3 staining in hereditary cerebral hemorrhage with amyloidosis‐Dutch type

Hereditary cerebral hemorrhage with amyloidosis‐Dutch type (HCHWA‐D) is an early onset hereditary form of cerebral amyloid angiopathy (CAA) pathology, caused by the E22Q mutation in the amyloid β (Aβ) peptide. Transforming growth factor β1 (TGFβ1) is a key player in vascular fibrosis and in the formation of angiopathic vessels in transgenic mice. Therefore, we investigated whether the TGFβ pathway is involved in HCHWA‐D pathogenesis in human postmortem brain tissue from frontal and occipital lobes. Components of the TGFβ pathway were analyzed with quantitative RT‐PCR. TGFβ1 and TGFβ Receptor 2 (TGFBR2) gene expression levels were significantly increased in HCHWA‐D in comparison to the controls, in both frontal and occipital lobes. TGFβ‐induced pro‐fibrotic target genes were also upregulated. We further assessed pathway activation by detecting phospho‐SMAD2/3 (pSMAD2/3), a direct TGFβ down‐stream signaling mediator, using immunohistochemistry. We found abnormal pSMAD2/3 granular deposits specifically on HCHWA‐D angiopathic frontal and occipital vessels. We graded pSMAD2/3 accumulation in angiopathic vessels and found a positive correlation with the CAA load independent of the brain area. We also observed pSMAD2/3 granules in a halo surrounding occipital vessels, which was specific for HCHWA‐D. The result of this study indicates an upregulation of TGFβ1 in HCHWA‐D, as was found previously in AD with CAA pathology. We discuss the possible origins and implications of the TGFβ pathway deregulation in the microvasculature in HCHWA‐D. These findings identify the TGFβ pathway as a potential biomarker of disease progression and a possible target of therapeutic intervention in HCHWA‐D.     

IL-22在气道变应性疾病中的作用

IL-22是一种功能复杂的细胞因子,属于IL-10细胞因子家族成员,最初被命名为IL-10相关T细胞来源诱导因子,由179个氨基酸残基组成.体内的多种活化免疫细胞可以分泌IL-22,它的受体是由IL-22R1和IL-10R2构成的异源二聚体.IL-22在固有免疫和适应性免疫中均发挥重要作用.IL-22既有抗炎作用,也有促炎作用,参与炎症性疾病和多种免疫性疾病,例如银屑病、类风湿性关节炎和炎症性肠病.另外,IL-22在消化道的感染性疾病中起到抵抗微生物的作用.因而研究IL-22在气道变应性疾病中的作用很有意义.