ABSTRACT
Abstract The gut is the main organ that mediates the contact between antigens with our organism, controlling the immune response against environmental factors, such as microbiota and food. Innate lymphoid cells participate in the gut-associated lymphoid tissue (GALT) maturation during the prenatal and early postnatal periods. After birth, breast milk provides the essential elements for the continuity of development of this tissue, leading to structural changes and healthy microbiota installation. The microbiota participates in the organogenesis of the GALT, as in the formation of intestinal villi, stimulating the proliferation of stem cells and maintaining the integrity of epithelial barrier. Foods are also involved in maturation of the GALT, where the protein source depletion reduced the number of resident lymphocytes. This unique microenvironment present in the intestinal lamina propria (LP) and mesenteric lymph nodes (mLN) induce tolerance to innocuous antigens from the diet, known as Oral Tolerance. Antigens sampled by intestinal epithelium cells are transferred to specialized dendritic cells, residing in the LP, which migrate to the mesenteric lymph nodes where they participate in the induction of regulatory T cells (Treg). Understanding these phenomena may establish the intestinal mucosa as a tool in therapy of inflammatory bowel diseases and immunological disorders.
Subject(s)
Peripheral Tolerance , Microbiota , Immune System , Intestines/physiologyABSTRACT
Abstract: introduction: regulatory T-cells are the main component of peripheral tolerance and their level is decreased in autoimmunity. In dental amalgam, a mixture of metals is used as a restorative material. During daily a ctivities, these metals are ingested and affect renal, neurosensory and immune systems. Studies have demonstrated an increased risk of autoimmune diseases in patients with dental amalgam fillings. It was hypothesized that the percentage of regulatory T-cells decreases in individuals with amalgam fillings. Therefore this study was designed to determine and compare the percentage of regulatory T-cells in individuals with and without amalgam fillings. Material and Methods: This was a cross-sectional study. Subjects were divided into two groups with each group consisting of 40 individuals. Group I (study group) comprised individuals with amalgam fillings, and Group II (control group), individuals without amalgam fillings in their teeth. Blood samples of all the participants were collected and tagged with CD4 FITC, CD25 PE and CD127 PerCP-Cy monoclonal antibodies for the detection of regulatory T-cells, FACSCalibur was used for this purpose. Results: The percentage of regulatory T-cells in the control group was high (77.77 +/- 5.54 percent) compared to the study group (76.09 +/- 7.68 percent), however, on comparison, the difference was not statistically significant (p=0.25). Conclusion: Dental amalgam fillings did not show a declining effect on the percentage of regulatory T-cells.
Resumen: introducción: las células T reguladoras son el principal componente de la tolerancia periférica y su nivel se reduce en la autoinmunidad. En las obturaciones de amalgama, una mezcla de metales se utiliza como un material de restauración. Durante las actividades diarias, estos metales se ingieren y afectan el sistema renal, neurosensorial e inmunológico. Los estudios han demostrado un aumento del riesgo de enfermedades autoinmunes en pacientes con amalgamas dentales. Se planteó la hipótesis que el porcentaje de células T reguladoras disminuye en individuos con obturaciones de amalgama. Por tanto, este estudio fue diseñado para determinar y comparar el porcentaje de células T reguladoras en individuos con y sin obturaciones de amalgama. Material y Métodos: Se realizó un estudio de corte transversal. Los sujetos fueron divididos en dos grupos, cada uno con 40 individuos. El grupo I (de estudio) estuvo conformado por individuos con obturaciones de amalgama y el grupo II (de control) por individuos sin obturaciones de amalgma. Se colectaron muestras de sangre, las que fueron marcadas con anticuerpos monoclonales CD4 FITC, CD25 PE y CD127 PerCP-C para detectar las células T reguladoras, se utilizó FACSCalibur para este propósito. Resultados: El porcentaje de células T reguladoras en el grupo control fue alta (77,77 +/- 5,54 por ciento) en comparación con el grupo de estudio (76,09 +/- 7,68 por ciento), pero esta diferencia no fue estadísticamente significativa (p=0,25). Conclusión: Las obturaciones de amalgama no se asociaron con una disminución en el porcentaje de células T reguladoras.
Subject(s)
Male , Female , Humans , Adult , Autoimmunity , Dental Amalgam , Peripheral Tolerance , T-Lymphocytes, Regulatory , Cross-Sectional Studies , PakistanABSTRACT
La autoinmunidad se caracteriza por una pérdida de la tolerancia inmunológica que produce la destrucción de células y tejidos propios. El sistema del complejo mayor de histocompatibilidad posee una fuerte asociación con las enfermedades autoinmunes aunque determinados genes que codifican para citoquinas y moléculas coestimuladoras incrementan la susceptibilidad genética. Estudios de concordancia entre gemelos monocigóticos demuestran el papel de los factores ambientales en la aparición de las enfermedades autoinmunes. A pesar de los avances científicos producidos en esta área de investigación, los mecanismos subyacentes de estas afecciones son desconocidos. El objetivo de este trabajo es exponer de forma sintetizada el papel de los factores genéticos, inmunológicos y ambientales en la autoinmunidad
The autoimmunity is characterized by a loss of immunologic tolerance producing the destruction of cells and own tissues. The major complex system of histocompatibility has a close association with the autoimmune diseases although determined genes codifying for cytokines and co-stimulators molecules increase the genetic susceptibility. Concordance studies among monozygotic twins demonstrate the role of environmental factors in appearance of autoimmune diseases. Despite the scientific advances achieved in this research field, the underlying mechanisms of these affections are unknown. The objective of present paper is to expose in a summarized way the role of the genetic, immunologic and environmental factors in autoimmunity
Subject(s)
Autoimmunity/physiology , Immunologic Factors/deficiency , Gene-Environment Interaction , Genetic Predisposition to DiseaseABSTRACT
Regulatory T (TReg) cells are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases. However, they also limit beneficial responses by suppressing sterilizing immunity and limiting antitumor immunity. TReg cells characterized by expression of the transcription factor Foxp3 play a key role in immune homeostasis. Rather than a monomorphic population strictly determined by Foxp3 as a 'master regulator', the emerging view is one of TReg cells as a population with many levels of complexity. Distinct subphenotypes of Foxp3+ TReg cells are found in different anatomical locations. This review will focus on these novel aspects of TReg cell diversity, and discuss recent findings regarding human TReg cells, including the ontogeny and development of TReg cell subsets that have naive or memory phenotypes, the unique mechanisms of suppression mediated by TReg cell subsets and factors that regulate TReg cell lineage commitment. We also will discuss future studies that are needed for the successful therapeutic use of human TReg cells.
Subject(s)
Humans , Autoimmune Diseases , Homeostasis , Immune System , Memory , Peripheral Tolerance , Phenotype , T-Lymphocytes, Regulatory , Transcription FactorsABSTRACT
Objective:To clarify the role of Aire on the production of regulatory T cells on mice.Methods:The distribution of CD4~+CD25~+T cells and the expression of Foxp3 mRNA from Aire~ -/- thymus and spleen were separately analyzed using FACS and real-time PCR.Results:Compared with control mice, the total numbers of thymocytes/splenocytes and T cells from Aire~ -/- mice did not show any significant changes; The total CD4~+CD25~+ regulatory T-cell number and Foxp3 mRNA expression did not exhibit any statistically difference; The ratios of CD4~+CD25~+T cells out of CD4~+T cells were similar based on adult /day3/day7 mice analysis.Conclusion:Aire gene does not affect the production of CD4~+CD25~+ regulatory T cells.