A DNA vaccine expressing an optimized secreted FAPα induces enhanced anti-tumor activity by altering the tumor microenvironment in a murine model of breast cancer

Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8⁺ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα⁺ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.     

IgE-mediated regulation of IL-10 and type I IFN enhances rhinovirus-induced Th2 differentiation by primary human monocytes

Rhinovirus (RV) infections are linked to the development and exacerbation of allergic diseases including allergic asthma. IgE, another contributor to atopic disease pathogenesis, has been shown to regulate DC antiviral functions and influence T cell priming by monocytes. We previously demonstrated that IgE-mediated stimulation of monocytes alters multiple cellular functions including cytokine secretion, phagocytosis, and influenza-induced Th1 development. In this study, we investigate the effects of IgE-mediated stimulation on monocyte-driven, RV-induced T cell development utilizing primary human monocyte-T cell co-cultures. We demonstrate that IgE crosslinking of RV-exposed monocytes enhances monocyte-driven Th2 differentiation. This increase in RV-induced Th2 development was regulated by IgE-mediated inhibition of virus-induced type I IFN and induction of IL-10. These findings suggest an additional mechanism by which two clinically significant risk factors for allergic disease exacerbations—IgE-mediated stimulation and rhinovirus infection—may synergistically promote Th2 differentiation and allergic inflammation.     

Therapeutic effect of mesenchymal stem cell on Hashimoto’s thyroiditis in a rat model by modulating Th17/Treg cell balance

Abstract

The autoimmune condition Hashimoto’s thyroiditis (HT) is a disease wherein lymphocytes mediate the autoimmune damage and destruction of the thyroid gland. There are currently no effective means of treating HT, with the primary strategies of thyroid hormone therapy, surgery, or immunomodulatory therapy being associated with serious risks and side effects. There is thus a clear and urgent need to identify novel treatments for HT. In this study, we utilize female SD rats induced HT to evaluated the ability of transplanted MSCs to regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. The results showed that Rats in the HT model group exhibited increased thyroid autoantibody levels consistent with successful model development, whereas these levels were lower in rats treated with MSCs. There were also fewer thyroid lesions and less lymphoid infiltration of the thyroid in MSC-treated rats relative to HT model rats, as well as fewer Th17 cells and more Treg cells – an observation consistent with the cytokine analyses. All of these showed that MSCs can regulate Th17/Treg interactions in a rat Hashimoto’s thyroiditis (HT) model system. It suggested that transplanted MSCs could be a potential immunotherapy strategy for the treatment of Hashimoto’s thyroiditis.     

Psoriasis confined strictly to vitiligo areas – a Koebner‐like phenomenon?

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.     

Th1/Th2炎症极化与肺气肿和肺纤维化

肺气肿具有Ⅰ型T辅助细胞（Th1）炎症极化的特征，表现为损伤过度和修复不足，肺实质的破坏增加，肺间质变薄。与之相反，肺纤维则具有Ⅱ型T辅助细胞（Th2）炎症极化，表现为损伤后修复过度，肺间质增厚，胶原沉积。通过调控Th1和Th2的炎症趋势来控制肺组织的损伤和修复的结局可能会为肺气肿和肺纤维化的防治提供新思路。     

柴胡疏肝散、四君子汤对肝郁、脾虚大鼠Th细胞蛋白激酶C表达的影响

目的研究柴胡疏肝散、四君子汤对肝郁、脾虚大鼠Th细胞蛋白激酶C(PKC)表达的影响及其意义。方法应用RT—PCR法研究柴胡疏肝散、四君子汤对Th细胞PKCmRNA表达的影响。结果脾虚时PKCmRNA表达水平明显低于正常对照组 (P <0 .0 5 ) ,四君子汤治疗后恢复正常 (P <0 .0 5 ) ,柴胡疏肝散治疗后仍明显低于正常对照组 ;肝郁时PKCmRNA表达水平明显高于正常对照组 (P <0 .0 5 ) ,柴胡疏肝散治疗后恢复正常 (P <0 .0 5 ) ,但四君子汤治疗效应不明显。结论肝脾两脏在T细胞尤其是Th0的活化中具有相关性 ;PKC参与了肝脾这种相关的发生。     

地塞米松对哮喘大鼠Th1/Th2失衡及嗜酸细胞fas、bcl-2 mRNA表达的影响

目的:观察地塞米松(DXM)对哮喘大鼠Th1/Th2失衡以及嗜酸细胞(EOS)fas、bcl-2 mRNA表达的影响,探讨糖皮质激素治疗哮喘气道炎症的作用机制.方法:清洁级雄性SD大鼠30只,随机分为3组:正常对照组(C),哮喘组(A),地塞米松治疗组(T),每组10只.采用卵清白蛋白制作大鼠哮喘模型.用夹心酶联免疫吸附试验(sandwich ELISA)法检测血浆及支气管肺泡灌洗液(BALF)中IL-4、IFN-γ的水平;用原位杂交法检测fas和bcl-2 mRNA在气道壁EOS上的表达.结果:A组大鼠IFN-γ表达水平较C组明显下调(P＜0.01),同时IL-4表达水平则有明显上调(P＜0.01),表现出明显的Th1/Th2失衡.fas mRNA的表达在A组明显下降(P＜0.01),bcl-2 mRNA的表达则有明显上调(P＜0.01).地塞米松治疗在纠正A组大鼠Th1/Th2失衡的同时可上调fas mRNA的表达,下调bcl-2 mRNA的表达.结论:纠正哮喘大鼠Th1/Th2失衡,调节EOS fas、bcl-2 mRNA的表达是地塞米松减轻哮喘气道炎症的可能机制之一.     

Evaluation of allergenicity of genetically modified soybean protein extract in a murine model of oral allergen-specific sensitization

Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods.     

大学生篮球运动员集训期间部分淋巴细胞亚群和Th1/Th2细胞因子mRNA表达变化分析

目的:探讨大负荷体能训练对大学生篮球运动员细胞免疫功能的影响。方法:14名男子大学生篮球运动员进行为期16周的集训,在训练期间分次对运动员外周血淋巴细胞亚群(CD3+、CD4+/CD8+淋巴细胞比值、NK细胞比例)和Th1/Th2细胞因子 mRNA表达进行检测。结果:在两次分别持续了6周的训练期后,运动员外周血CD3+淋巴细胞数于增加后出现显著下降,从第7周的峰值(59.74±7.18)下降至第16周的最低值(52.02±7.92)(P<0.001);CD8+细胞数第16周(31.15±6.25)与第3周(37.98±7.05)相比显著下降(P<0.05);NK细胞数从第7周的最高值(19.62±5.21)下降至第14周的最低值(14.41±7.93)(P<0.05);IL-4 mRNA表达训练后与基础值(6.56±0.71)相比显著增加,从第7周的7.04±0.35和第14周的7.30±0.25,直至第16周达到最大值7.36±0.45(P<0.05),其他指标的变化不具有统计学意义。结果提示,大负荷训练使运动员细胞免疫功能削弱,Th1/Th2平衡向Th2方向漂移。     

Epitope Context and Reshaping of Activated T Helper Cell Repertoire

In recent years, a growing interest in the study of peptide antigenicity in relation to the role of flanking sequences and protein topology in processing, presentation, and recognition has been observed. However, the information available on the antigenicity of recombinant fusion proteins and their effect on the selection of antigen receptor repertoires is limited. To analyze the role of molecular topology of T epitopes in a system relevant to human pathology, we have used the bacterially expressed Schistosoma japonicum glutathione S transferase (GST) to construct recombinant antigens containing HIV-1 derived T cell determinants, and human T cell clones specific for these determinants. We found that antigenicity of a given GST—peptide combination was not the same when T cells and antigen presenting cells from different individuals were tested. Our results show that differences in processing and presentation of chimeric proteins are not dictated by the use of diverse restriction elements. We also found that the context in which an antigenic peptide is delivered affects the recruited repertoire as defined according to T cell receptor Vβ usage and fine specificities of selected T cells.