Immunopathological features of palatine tonsil characteristic of IgA nephropathy: IgA1 localization in follicular dendritic cells

IgA nephropathy (IgAN) is generally thought to be mediated by the glomerular deposition of circulating immune complexes containing IgA as the major antibody component. Upper respiratory infections and tonsillitis often precede IgAN. and in some cases tonsillectomy is affective for the (treatment of IgAN. Thus, the tonsil seems to be a unique organ causing initial and/or progressive events to generate nephritogenic immune complexes in IgAN. in this study we focused on the analysis of immunopathological features of the palatine tonsil characteristic of IgAN patients by using an immunohistochemical technique. The IgAl subclass was demonstrated in follicular dendritic cells (FDC) of the tonsil of IgAN patients, but not in FDC of non-IgAN controls. On the other hand, IgA2, IgG, IgM and C3 did not show any differences in distribution between the two groups. Moreover, the expression of decay-accelerating factor (DAF), an inhibitor of homologous complement activation, and transforming growth factor-beta I (TGF-/β1). an inducer of antibody-producing ceils to IgA class switching, in FDC and interdigitating dendritic cells of the tonsil, respectively, which was also clarified in this study for the first time, was found to be identically distributed in the two groups. These findings may support the idea that IgA1. possibly in an immune complex form, is trapped by FDC and plays an important role in the persistent activation of particular B cell repertoires responsible for ihe onset and/or progression of IgAN.     

Synaptogenesis and myelinogenesis in dissociated cerebral cells from rat embryo on polylysine coated surfaces

Summary The appearance of myelinated axons and establishment of synaptic contacts in dissociated cells from rat embryo cerebral hemispheres grown on polylysine precoated surfaces were studied by light and electron microscopy. Typical myelin lamellae ensheathing axons were observed as early as the eighth day. Immature synaptic profiles exhibiting slight membrane thickening and few synaptic vesicles were observed after seven days. At 3 weeks, mature synapses containing many synaptic vesicles and the typical irregular membrane thickening could be seen. It is suggested that the presence of polylysine may provide a support which enhances the attachment and subsequent establishment of contacts between neuronal and glial cells, resulting in the early onset of myelin formation.     

Altered chromatin landscape in circulating T follicular helper and regulatory cells following grass pollen subcutaneous and sublingual immunotherapy

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Demonstration of T4, T8, M1 and B7 determinants on human T cells with a rosette test: implications for the assay specificity of monoclonal antibodies

Under optimal test conditions significantly more freshly isolated human T cells reacted with OKT4, OKT8, OKM1 and OKB7 monoclonal antibodies (Mabs) in the indirect antiglobulin rosetting reaction (IARR) than by indirect immunofluorescence. Rabbit erythrocytes (E) coated with anti-mouse immunoglobulin were more sensitive indicator cells in the IARR than similarly coated sheep E. Treatment of T cells with neuraminidase further enhanced T cell reactivity in the IARR with each Mab so that an average of 60% or more of T cells were T4+, T8+ and M1+ and at least 40% had the T4+ T8+ phenotype. The various findings suggest that the rosette assay detects determinants on T cells that are expressed below the detection threshold of immunofluorescence. Moreover, these findings indicate that the cellular specificities of a particular Mab may change when one assay system is substituted for another or when the protocol of a particular assay is altered.     

EB病毒LMP2A特异性CTL的体外诱导及分析

用EBV LMP2A重组痘苗病毒 (rVV LMP2A )转染人树突状细胞 (DC ) ,转染后的DC分别在第 1、 7、 14天刺激相同MHC背景的T细胞 ,在IL 2作用下诱导LMP2A特异性CTL。用LDH释放法检测CTL杀伤活性 ;流式细胞术 (FACS )检测CTL诱导分化过程中CD3+ 、CD4 + 、CD8+ 、CD5 6 + 等细胞的分群变化 ;RT PCR检测细胞分化过程中FasLmRNA表达 ;生物活性法检测功能性细胞因子IFN γ的分泌。结果显示本法诱导的CTL对靶细胞有特异性杀伤活性 ,第 2次和第 3次DC刺激后杀伤活性有所上升 ;在CTL诱导分化的第 7、 14、 2 1天细胞分群以CD4 + 、CD8+ 细胞为主 ;RT PCR证实所诱导的细胞内有FasLmRNA的表达 ;随细胞培养天数的增加IFN γ分泌增加 ,在第 14天达到较高水平。研究表明重组痘苗病毒载体rVV LMP2A转染的DC刺激T细胞可诱导出EBV LMP2A特异性CTL。     

重组小鼠干细胞逆转录病毒载体高效基因转染CD41+、UT7、U937和MDA-MB-435细胞

目的:研究重组小鼠干细胞逆转录病毒载体介导基因转染,探索一条高效基因转染的途径,为重组小鼠干细胞逆转录病毒载体在基因转染中的应用提供理论依据和奠定实验基础。方法:①逆转录病毒载体的构建:EC1-4(repeats1-4ofcadherin-5extracellulardomains)基因克隆产物和mutant(Ser222A)MEK1基因克隆产物,Bg1Ⅱ和EcoRⅠ限制性内切核酸酶切割后,克隆进入逆转录病毒表达载体pMSCV。②CD41⁺细胞的获取和细胞培养:从脐带血分离的CD34⁺细胞通过TPO诱导表达CD41,FACS分离CD41⁺细胞。高糖DMEM培养液培养NIH3T3和MDA-MB-435细胞,U937细胞培养在RPMI-1640培养液,UT7细胞是细胞因子依赖性细胞株,Iscove'smodifiedDulbeco's培养液中加入GM-CSF。③测定病毒滴度:逆转录病毒载体转入包装细胞293,36h后收集病毒上清液,感染NIH3T3细胞,流式细胞仪测定病毒滴度。④Westernblot:基因转染CD41⁺、UT7、U937和MDA-MB-435细胞,Westernblot检测基因产物的表达。结果:293细胞产生高滴度MEK1pMSCV病毒:3.1×10⁷,高滴度EC1-4pMSCV病毒:1.0×10⁸。用稀释8倍的病毒转染基因,重组逆转录病毒MEK1pMSCV转染白血病细胞株UT7和U973,GFP阳性细胞(转染阳性细胞)分别是60.73％、72.56％。重组逆转录病毒MEK1pMSCV转染原代培养细胞CD41⁺,GFP阳性细胞为30.57％。重组逆转录病毒EC1-4pMSCV转染人乳腺癌细胞株MDA-MB-435,GFP阳性细胞为97.54％。TPO作用CD41⁺和UT7细胞以及血清对U973细胞的作用,显示出外源mutationMEK基因的dominantnegative的效应,实验组磷酸化的MEK1减少。EC1-4基因转染的MDA-MB-435细胞表达了EC1-4基因产物。结论:重组小鼠干细胞逆转录病毒载体能高效基因转染CD41⁺、UT7、U937和MDA-MB-435细胞,转染的基因能稳定地表达。     

The frequency of type 2 CD8+ T cells is increased in peripheral blood from patients with psoriasis vulgaris

Studies have suggested that psoriasis vulgaris is mediated by type 1 T cells. In this study, we examined both chemokine receptor expression and intracellular cytokine production by circulating T cells to check the type 1/type 2 balance in psoriasis. CCR4⁺ and CXCR3⁺ T cells predominantly produced interleukin-4 and interferon-, respectively. The frequency of interferon--producing cells and that of CXCR3⁺ cells in circulating CD4⁺ T cells were similar for psoriatic patients and healthy control subjects. By contrast, the frequency of CCR4⁺CD8⁺ T cells and CCR4/CXCR3 ratio in circulating CD8⁺ T cells were significantly higher in psoriatic patients than in healthy control subjects. Analysis of intracellular cytokine production also indicated relative increase of type 2 CD8⁺ T (Tc2) cells in peripheral blood from psoriatic patients. The frequency of circulating Tc2 cells directly correlated with Psoriasis Area and Severity Index. Immunohistochemical analysis showed that not only CXCR3⁺CD8⁺ T cells but also a similar number of CCR4⁺CD8⁺ T cells infiltrated the psoriatic epidermis and dermis. Our findings suggest an increase in Tc2 cell number in blood from psoriatic patients, and the association of Tc2 cells with inflammation in psoriasis.     

Intravenous tufted angioma

A case of a rare vascular tumor, intravenous tufted angioma, is described. A 51-year-old Japanese man presented with a 12x8 mm solitary reddish nodule on the right foot, which had been found at birth. Histologically, the tumor was confined to a malformed vein and was characterized by nodular aggregates of plump cells. The aggregates showed a compact proliferation of round cells, including capillary-forming cells. Venous angiomatous areas were also observed. No multinucleated giant cells were seen. Immunohistochemically, the capillary-forming cells in the aggregates and the endothelial cells in the angiomatous areas were positive for endothelial markers (factor VIII-related antigen, CD31, CD34). Pericyte-like cells expressing alpha-smooth muscle actin and muscle actin, and macrophage-like cells, which stained for factor XIIIa, were intermingled in the cellular aggregates. Flow cytometric analysis showed diploidy. The tumor may be a hamartomatous lesion modified by secondary reactive changes, and it may represent a distinctive clinicopathological entity that is closely related histogenetically and perhaps pathologically to tufted angioma and the recently described "giant cell angioblastoma".     

PCR扩增孕妇外周血DNA进行胎儿性别诊断

采用密度梯度离心技术对40例孕妇外用血中胎儿细胞进行富集,并用PCR技术扩增了Y染色体特异重复序列,以产前基因诊断胎儿性别,结果38例胎儿性别诊断准确,证明此技术可作为无创伤性方法用于X连锁遗传病的产前诊断.