The role of CD4+ CD25+ Treg in the mechanism of autoimmune auditory neuropathy in SD rats / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the role of CD4+CD25+regulatory cell (CD4+CD25+Treg) in auditory neuropathy (AN) using a rat model of autoimmune auditory neuropathy. Methods: The SD rats were immunized with P0 protein emulsified in complete Freunds adjuvant for 8 weeks. The number of CD4+CD25+Treg in peripheral blood and cochlea and the expression of Foxp3 gene in cochlea were detected respectively 2, 4, 6 and 8 weeks after the immunization with P0 protein in rats. Then CD4+CD25+Treg were transferred intravenously to the AN rats at 2, 4, 6 and 8 weeks of the immunization, respectively. The change of auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) were detected, and the morphological changes in the inner ear were investigated. Results: The number of CD4+CD25+Treg in the peripheral blood of AN rats decreased gradually after 2, 4, 6 and 8 weeks of P0 protein immunization. The number of CD4+CD25+Treg in cochlea gradually increased with the prolongation of immunization time, but the expression of Foxp3 gene in cochlea gradually decreased over time. After intravenous transplantation of CD4+CD25+Treg in AN rats, the threshold of ABR response decreased, and DPOAE had no significant change. The number of spiral ganglion neurons in cochlea increased, and hair cells had no significant change under electron microscope. Conclusions: The decrease in the number and function of CD4+CD25+Treg reduces its inhibitory effect on autoimmune response and promotes the occurrence of autoimmune auditory neuropathy in AN rats. Adoptive transfer of CD4+CD25+Treg can reduce the autoimmune response and promote the recovery of autoimmune auditory neuropathy.

CD4+CD69+ T cells and CD4+CD25+FoxP3+ Treg cells imbalance in peripheral blood, spleen and peritoneal lavage from pristane-induced systemic lupus erythematosus (SLE) mice

Abstract Background: Adaptive immune cells, including CD4+CD69+ and CD4+CD25+FoxP3+ regulatory T (Treg) cells, are important for maintaining immunological tolerance. In human systemic lupus erythematosus (SLE), CD4+CD25+FoxP3+ Treg cells are reduced, whereas CD69 expression is increased, resulting in a homeostatic immune imbalance that may intensify autoreactive T cell activity. To analyze the mechanisms implicated in autotolerance failure, we evaluated CD4+CD69+ and CD4+CD25+FoxP3+ T cells and interleukin profiles in a pristane-induced SLE experimental model. Methods: For lupus induction, 26 female Balb/c mice received a single intraperitoneal 0.5 ml dose of pristane, and 16 mice received the same dose of saline. Blood and spleen samples were collected from euthanized mice 90 and 120 days after pristane or saline inoculation. Mononuclear cells from peripheral blood (PBMC), peritoneal lavage (PL) and splenocytes were obtained by erythrocyte lysis and cryopreserved for further evaluation by flow cytometry using the GuavaEasyCyte TM HT. After thawing, cells were washed and stained with monoclonal antibodies against CD3, CD4, CD8, CD25, CD28, CD69, FoxP3, CD14 and Ly6C (BD Pharmingen TM). Interleukins were quantified using Multiplex® MAP. The Mann-Whitney test and the Pearson coefficient were used for statistical analysis, and p < 0.05 considered significant. Results: Compared with the controls, SLE-induced animals presented increased numbers of CD4+CD69+ T cells in the blood on T90 and T120 (p = 0.022 and p = 0.008) and in the spleen on T120 (p = 0.049), but there were decreased numbers in the PL (p = 0.049) on T120. The percentage of Treg was lower in blood (p < 0.005 and p < 0.012) on T90 and T120, in spleen (p = 0.043) on T120 and in PL (p = 0.001) on T90. Increased numbers of CD4+ CD69+ T cells in the PL were positively associated with high IL-2 (p = 0.486) and IFN-γ (p = 0.017) levels, whereas reduced Treg cells in the blood were negatively correlated with TNFα levels (p = 0.043) and positively correlated with TGFβ1 (p = 0.038). Conclusion: Increased numbers of CD4+CD69+ T cells and reduced numbers of CD4+CD25+FoxP3+ Treg cells with an altered interleukin profile suggests loss of autotolerance in pristane-induced lupus mice, which is similar to human lupus. Therefore, this model is useful in evaluating mechanisms of cellular activation, peripheral tolerance and homeostatic immune imbalance involved in human SLE.

The role of regulatory T cells, interleukin-10 and in vivo scintigraphy in autoimmune and idiopathic diseases - Therapeutic perspectives and prognosis / O papel de células T regulatórias, da interleucina 10 e da cintilografica in vivo em doenças autoimunes e idiopáticas - Perspectivas terapêuticas e prognóstico

Summary Previous studies have demonstrated the expression of the CD25 marker on the surface of naturally occurring T cells (Tregs) of mice, which have a self-reactive cellular profile. Recently, expression of other markers that aid in the identification of these cells has been detected in lymphocyte subtypes of individuals suffering of autoimmune and idiopathic diseases, including: CD25, CTLA-4 (cytotoxic T-lymphocyte antigen 4), HLA-DR (human leukocyte antigen) and Interleukin 10 (IL-10), opening new perspectives for a better understanding of an association between such receptors present on the cell surface and the prognosis of autoimmune diseases. The role of these molecules has already been described in the literature for the modulation of the inflammatory response in infectious and parasitic diseases. Thus, the function, phenotype and frequency of expression of the a-chain receptor of IL-2 (CD25) and IL-10 in lymphocyte subtypes were investigated. Murine models have been used to demonstrate a possible correlation between the expression of the CD25 marker (on the surface of CD4 lymphocytes) and the control of self-tolerance mechanisms. These studies provided support for the presentation of a review of the role of cells expressing IL-2, IL-10, HLA-DR and CTLA-4 receptors in the monitoring of immunosuppression in diseases classified as autoimmune, providing perspectives for understanding peripheral regulation mechanisms and the pathophysiology of these diseases in humans. In addition, a therapeutic approach based on the manipulation of the phenotype of these cells and ways of scintigraphically monitoring the manifestations of these diseases by labeling their receptors is discussed as a perspective. In this paper, we have included the description of experiments in ex vivo regulation of IL-10 and synthesis of thio-sugars and poly-sugars to produce radiopharmaceuticals for monitoring inflammation. These experiments may yield benefits for the treatment and prognosis of autoimmune diseases.

Resumo Estudos anteriores já haviam demonstrado a expressão do marcador CD25 na superfície de células T de ocorrência natural (Tregs) de camundongos, que apresentam perfil celular autorreativo. Recentemente, foi detectada, em subtipos de linfócitos de indivíduos acometidos por doenças autoimunes e de causa idiopática, a expressão de outros marcadores, que auxiliam na identificação dessas células, entre os quais: CD25, CTLA-4 (cytotoxic T-lymphocyte antigen 4), HLA-DR (human leucocyte antigen) e Interleucina 10 (IL-10), abrindo novas perspectivas para a melhor compreensão de uma associação entre esses receptores presentes na superfície celular e o prognóstico de doenças autoimunes. O papel dessas moléculas já havia sido descrito na literatura na modulação da resposta inflamatória em doenças infectoparasitárias. Dessa forma, foram investigados a função, o fenótipo e a frequência de expressão, do receptor de cadeia a da IL-2 (CD25) e de IL-10 em subtipos de linfócitos. O modelo murino tem sido utilizado para demonstrar uma possível correlação entre a expressão do marcador CD25 (na superfície de linfócitos CD4) e o controle dos mecanismos de autotolerância. Essas pesquisas forneceram suporte para apresentação de uma revisão sobre o papel das células que expressam os receptores de IL-2, IL-10, HLA-DR e CTLA-4 no monitoramento da imunossupressão, em doenças de classificação autoimune, abrindo perspectivas para o entendimento dos mecanismos de regulação periférica e sobre a fisiopatologia dessas doenças no ser humano. Além disso, é discutida como perspectiva uma abordagem terapêutica fundamentada na manipulação do fenótipo dessas células, bem como de modos de monitoramento cintilográfico das manifestações dessas doenças, por meio da marcação de seus receptores. Nestes, foram incluídas descrições das experiências em regulação ex-vivo de IL-10; de síntese de tioaçúcares e de poliaçúcares para produção de radiofármacos para monitoramento de inflamações. Essas experiências podem trazer benefícios na terapia e no prognóstico de doenças autoimunes.

The Role of CD4(+)CD25(bright) Regulatory T Cells in the Maintenance of Pregnancy, Premature Rupture of Membranes, and Labor

PURPOSE: The aim of this study was to evaluate the changes of the regulatory T cell subset in peripheral blood caused by gestational age and premature rupture of membranes (PROM) with or without labor to verify the role of regulatory T cells in pregnancy. PATIENTS AND METHODS: We investigated regulatory T cell distribution in the peripheral blood of pregnancies during the first trimester (group I, n=2), the second trimester (group II, n=12), and the third trimester without PROM and labor (group III, n=15). In addition, we evaluated pregnancies in the third trimester complicated by PROM (group IV, n=4) and labor with no complication by PROM (Group V, n=5). Comparisons were made with non-pregnant controls (group VI, n=4) using flow cytometry. RESULTS: During uncomplicated pregnancy, the CD4(+)CD25(bright) regulatory T cell population decreased with advancing gestational age (group I=3.35+/-0.47, group II=2.91+/-1.44, group III=2.81+/-1.36, group VI=2.52+/-0.71, p=NS). When we compared group IV with group III and V to evaluate the changes of the regulatory T cells with PROM, the CD4(+)CD25(bright) regulatory T cell population was significantly decreased in group IV compared to group III (p=0.001) and group V (p=0.026). CONCLUSION: The present results revealed that the regulatory T cell population increased in early pregnancy but decreased in pregnancies complicated by PROM, indicating that regulatory T cells might be related to the maintenance of pregnancy.