A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall f...A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall focus on the regulation of their development and function in health and disease. T FH can be characterized on the basis of their phenotype and the pattern of secretion of cytokines. This fact is useful to study their participation in the generation of antibody deficiency in primary immunodeficiency diseases such as common variable immunodeficiency, X-linked hyper Ig M syndrome orX-linked lymphoproliferative disease. Increased numbers of T FH have been demonstrated in several autoimmune diseases and are thought to play a role in the development of autoantibodies. In chronic viral infections caused by the human immunodeficiency virus, hepatitis B or C virus, increased circulating T FH have been observed, but their role in the protective immune response to these agents is under discussion. Likewise, an important role of T FH in the control of some experimental protozoan infections has been proposed, and it will be important to assess their relevance in order to design effective vaccination strategies.展开更多
Background：The immunopathologic mechanism underlying dermatomyositis （DM） and polymyositis （PM） remains poorly understood.Many cytokines play a pathogenic role in DM and PM.lnterleukin 21 （IL-21） has a pleiotro...Background：The immunopathologic mechanism underlying dermatomyositis （DM） and polymyositis （PM） remains poorly understood.Many cytokines play a pathogenic role in DM and PM.lnterleukin 21 （IL-21） has a pleiotropic effect on inflammation regulation.This study aimed to detect the serum IL-21 level and investigate the expression of IL-21 and IL-21 receptor （IL-21 R） in muscle tissues of patients with DM and PM.Methods：Biopsied muscle samples were obtained from 11 patients with DM,12 with PM,and six controls;mRNA levels of IL-21 and IL-21 R were analyzed by real-time quantitative reverse transcription-polymerase chain reaction;and immunohistochemical staining was used to evaluate the protein expression of IL-21 and IL-21R.Serum samples were obtained from 36 patients with DM,19 with PM,and 20 healthy controls.The serum IL-21 level was detected by enzyme-linked immunosorbent assay.Results：The expression of IL-21 was upregulated in patients with DM and PM.The IL-21 mRNA level was significantly increased in muscle tissues of patients with DM and PM （DM vs.control,P =0.001;PM vs.control,P =0.001）,whereas IL-21R mRNA level in patients with DM/PM was not statistically different from that of healthy controls.Immunohistochemical staining showed both I L-21 and IL-21R were significantly expressed in the inflammatory cells in muscle tissues of patients with DM and PM.The serum IL-21 level was also significantly higher in patients with DM/PM than in controls （DM vs.control,49.12 [45.28,60.07] pg/ml vs.42.54 [38.69,48.85] pg/ml,P =0.00l;PM vs.control,50.77 [44.19,60.62] pg/ml vs.42.54 [38.69,48.85] pg/ml,P =0.005）.Conclusions：IL-21 expression is upregulated in patients with DM and PM in both muscle tissue and serum.In addition,IL-21R protein is highly expressed in affected muscle tissues of patients with DM and PM.IL-21 may play a pathogenic role through IL-21R in patients with DM and PM.展开更多
基金Supported by Consejo Nacional de Investigaciones Científicas y Técnicas,CONICET,PIP Nos.0032 and 11220120100619CO
文摘A correct antibody response requires the participation of both B and T lymphocytes and antigen presenting cells. In this review we address the role of follicular helper T lymphocytes(T FH) in this reaction. We shall focus on the regulation of their development and function in health and disease. T FH can be characterized on the basis of their phenotype and the pattern of secretion of cytokines. This fact is useful to study their participation in the generation of antibody deficiency in primary immunodeficiency diseases such as common variable immunodeficiency, X-linked hyper Ig M syndrome orX-linked lymphoproliferative disease. Increased numbers of T FH have been demonstrated in several autoimmune diseases and are thought to play a role in the development of autoantibodies. In chronic viral infections caused by the human immunodeficiency virus, hepatitis B or C virus, increased circulating T FH have been observed, but their role in the protective immune response to these agents is under discussion. Likewise, an important role of T FH in the control of some experimental protozoan infections has been proposed, and it will be important to assess their relevance in order to design effective vaccination strategies.
文摘Background：The immunopathologic mechanism underlying dermatomyositis （DM） and polymyositis （PM） remains poorly understood.Many cytokines play a pathogenic role in DM and PM.lnterleukin 21 （IL-21） has a pleiotropic effect on inflammation regulation.This study aimed to detect the serum IL-21 level and investigate the expression of IL-21 and IL-21 receptor （IL-21 R） in muscle tissues of patients with DM and PM.Methods：Biopsied muscle samples were obtained from 11 patients with DM,12 with PM,and six controls;mRNA levels of IL-21 and IL-21 R were analyzed by real-time quantitative reverse transcription-polymerase chain reaction;and immunohistochemical staining was used to evaluate the protein expression of IL-21 and IL-21R.Serum samples were obtained from 36 patients with DM,19 with PM,and 20 healthy controls.The serum IL-21 level was detected by enzyme-linked immunosorbent assay.Results：The expression of IL-21 was upregulated in patients with DM and PM.The IL-21 mRNA level was significantly increased in muscle tissues of patients with DM and PM （DM vs.control,P =0.001;PM vs.control,P =0.001）,whereas IL-21R mRNA level in patients with DM/PM was not statistically different from that of healthy controls.Immunohistochemical staining showed both I L-21 and IL-21R were significantly expressed in the inflammatory cells in muscle tissues of patients with DM and PM.The serum IL-21 level was also significantly higher in patients with DM/PM than in controls （DM vs.control,49.12 [45.28,60.07] pg/ml vs.42.54 [38.69,48.85] pg/ml,P =0.00l;PM vs.control,50.77 [44.19,60.62] pg/ml vs.42.54 [38.69,48.85] pg/ml,P =0.005）.Conclusions：IL-21 expression is upregulated in patients with DM and PM in both muscle tissue and serum.In addition,IL-21R protein is highly expressed in affected muscle tissues of patients with DM and PM.IL-21 may play a pathogenic role through IL-21R in patients with DM and PM.
