Morphological Interactions of Interdigitating Dendritic Cells with B and T Cells in Human Mesenteric Lymph Nodes

Interdigitating dendritic cells (IDC) of the human mesenteric lymph nodes (LN) were examined by two-color immunofluorescent microscopy and flow cytometry to clarify their exact localization, immunophenotype, and relationships with T and B cells. IDC were identified as HLA-DR(bright) large dendriform cells of the T cell areas co-expressing CD40, CD54 (ICAM-1), CD80 (B7/B7-1), CD83, and CD86 (B70/B7-2). The majority of IDC directly attached to a few IgD+ naive B cells as well as to numerous CD4+ T cells. When LN cells were singly suspended and briefly incubated in vitro, IDC formed clusters with IgD+ IgM+ naive B cells, but not with IgA+ or IgG+ B cells. When suspended LN cells were cultured, clustered B cells disappeared within 7 days, and on prolonged culture, some IDC developed into extensively dendriform cells forming stable complexes with several or sometimes numerous CD4+ IL-2R+ CD40L+ activated T cells. These findings indicate that resting naive B cells actually interact with IDC directly in T cell areas of human secondary lymphoid tissues. IDC have a non-antigen (Ag)-specific, strong affinity for resting naive B cells, but this affinity is transient and IDC cannot form stable complexes with B cells, although they can form stable complexes with activated T cells. It is suggested that the stable IDC/Ag-activated T cell complexes make it possible to capture and to stimulate rare Ag-specific resting naive B cells with high efficiency.     

Detection of Leishmania infantum in Dogs by PCR with Lymph Node Aspirates and Blood

The PCR technique was applied to the diagnosis of leishmaniasis in dogs, both serologically negative and positive. DNA was taken from lymph node aspirates and blood. The primers 13a and 13b, derived from Leishmania amazonies and Leishmania braziliensis kinetoplast DNA (kDNA), also amplified Leishmania infantum IPT1 constant region of minicircle kDNA. The amplified fragment is 116 bp long. It was cloned and the sequence was determined. A 70-bp inner fragment was designed and used as a probe in dot blot hybridization. A group of 124 dogs was examined, 37 of which showed typical symptoms of disease. PCR was performed on 124 blood samples and 52 lymph node aspirates. Using microscopic examination as the "gold standard," we calculated sensitivity, specificity, and positive and negative predictive values of 100% using lymph node aspirates and values of 85, 80, 95, and 57%, respectively, using blood samples. We found that 40% of the animals without lesions and 38% of the animals with clinical signs gave false-negative results by indirect immunofluorescence antibody testing. These animals could contribute to the spreading of infection among dogs, and represent a potential risk for human health as well.     

Treatment of Graft-versus-Host Disease with Naturally Occurring T Regulatory Cells

A significant body of evidence suggests that treatment with naturally occurring CD4⁺CD25⁺ T regulatory cells (Tregs) is an appropriate therapy for graft-versus-host disease (GvHD). GvHD is a major complication of bone marrow transplantation in which the transplanted immune system recognizes recipient tissues as a non-self and destroys them. In many cases, this condition significantly deteriorates the quality of life of the affected patients. It is also one of the most important causes of death after bone marrow transplantation. Tregs constitute a population responsible for dominant tolerance to self-tissues in the immune system. These cells prevent autoimmune and allergic reactions and decrease the risk of rejection of allotransplants. For these reasons, Tregs are considered as a cellular drug in GvHD. The results of the first clinical trials with these cells are already available. In this review we present important experimental facts which led to the clinical use of Tregs. We then critically evaluate specific requirements for Treg therapy in GvHD and therapies with Tregs currently under clinical investigation, including our experience and future perspectives on this kind of cellular treatment.     

Ultrastructural Analysis of Antibody Synthesis in Cells from Lymph and Lymph Nodes

A variety of cells containing antibody were found in lymph from sheep responding to secondary challenges with horseradish peroxidase. Antibody was present in blast cells in lymph within the perinuclear space, the endoplasmic reticulum, the Golgi apparatus and on polyribosomes. Some lymphocytes in lymph also contained antibody but in these cells it was located principally in the perinuclear space. No cells were found containing antibody distributed throughout their cytoplasm nor were any lymphocytes found with a Golgi apparatus positive for antibody. After the immune response in the lymph had died away, a population of cells containing antibody was still present in the regional lymph node. These were all plasma cells in which the antibody was present for the most part in a highly organized endoplasmic reticulum. Cells of this type were never found in the lymph. The cells containing the smallest amounts of antibody had a few discrete focal points in the perinuclear space and a few positive groups of ribosomes in their cytoplasm. The endoplasmic reticulum in some cells was filled completely with antibody, while in others positive segments were found adjacent to negative ones. The antibody in the cytoplasmic endoplasmic reticulum was in continuity with the antibody in the perinuclear space. The Golgi apparatus contained antibody in only a small proportion of the cells but when it was positive it was strongly so, suggesting that antibody was concentrated in this organelle. In some cells a positive reaction to horseradish peroxidase antibody appeared in the nucleus over the nucleoli. The significance of this finding is not known.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况。方法 应用免疫组化的方法研究胃癌病人颈部转移性淋巴结（实验组）和非转移性淋巴结（对照组）CXCR4的表达情况。 结果 实验组CXCR4的阳性率为98.1％,与对照组比较差异显著。 结论 CXCR4在胃癌的转移过程中有重要的作用。     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

趋化因子受体CXCR4在胃癌颈部转移淋巴结中表达的研究

目的 研究趋化因子受体CXCR4在胃癌转移性淋巴结中表达的情况.方法 应用免疫组化韵方法研究胃癌患者颈部转移性淋巴结、非转移性淋巴结及健康人颈部正常淋巴结CXCR4的表达情况.结果 实验组1(胃癌颈淋巴结转移)CXCR4的阳性率为98.1%,与实验组2(胃癌颈部非转移淋巴结)对照组比较差异具有统计学意义.结论 CXCR4在胃癌的转移过程中有重要的作用.     

A Specific Signalling Signature Characterizes the Development of Naturally Occurring and Antigen-Specific Regulatory T Cells

The molecular signals involved in the generation of thymic regulatory T cells (Treg) still remain controversial. It has been proposed that high avidity interactions are required for Treg selection. Here, we used double transgenic mice (TCR-HA × IgHA) and followed the kinetics and phosphorylation status of HA-specific Tregs that develop in the absence or presence of their agonist ligand expressed in the thymus, as well as of polyclonal “naturally ocurring” Tregs (nTregs). We found that, in basal conditions, nTregs showed enhanced basal phosphorylation of c-Cbl, Erk and PI3K, indicating their selection by high avidity ligands. However, in response to TCR cross-linking, both nTregs from Balb/c mice and HA-specific Tregs showed reduced levels of phosphorylated Erk1/2, c-Cbl and Akt. We conclude that thymus-derived Tregs display a characteristic “signalling signature” that suggests qualitative differences in TCR-mediated signalling that may not be explained merely by a higher TCR avidity.     

系统性红斑狼疮患者外周血调节性T细胞、Foxp3和IL-6的表达

目的探讨系统性红斑狼疮(systemic lupus erythematosus,SLE)患者外周血CD4 CD25 调节性T细胞(regulatory Tcells,Tregs)、Foxp3mRNA和血浆IL-6表达的意义。方法对38例SLE患者和16例正常人采用流式细胞术检测外周血CD4 CD25 Tregs百分率,RT-PCR检测Foxp3mRNA表达,ELISA法检测IL-6水平。结果①SLE活动组和非活动组的CD4 CD25 Tregs水平均显著低于正常对照组(P<0.01);②SLE活动组的Foxp3mRNA表达水平明显低于正常对照组(P<0.05);③SLE活动组和非活动组血浆的IL-6水平均显著高于正常对照组(P<0.01),而且活动组显著高于非活动组(P<0.05);④38例SLE患者的CD4 CD25 Tregs水平与SLEDAI评分呈显著性负相关(P<0.01),Foxp3mRNA水平与CD4 CD25 Tregs呈显著性正相关(P<0.01),血浆IL-6水平与SLEDAI评分之间呈显著性正相关(P<0.01),血浆IL-6水平与CD4 CD25 Tregs/CD4 细胞比值呈显著负相关(P<0.05)。结论CD4 CD25 Tregs和Foxp3以及IL-6可能在SLE的发生和发展中发挥重要作用。