Effect of TACI signaling on humoral immunity and autoimmune diseases

J Immunol Res. 2015;2015:247426. doi: 10.1155/2015/247426. Epub 2015 Mar 17.

Abstract

Transmembrane activator and calcium-modulating cyclophilin ligand interactor (TACI) is one of the receptors of B cell activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL). TACI is a regulator in the immune responses. TACI inhibits B cell expansion and promotes the differentiation and survival of plasma cells. The mechanisms underlying these effects probably involve changed expressions of some crucial molecules, such as B lymphocyte induced maturation protein-1 (Blimp-1) and inducible T-cell costimulator ligand (ICOSL) in B cells and/or plasma cells. However, abnormal TACI signaling may relate to autoimmune disorders. Common variable immune deficiency (CVID) patients with heterozygous mutations in TACI alleles increase susceptibility to autoimmune diseases. Taci (-/-) mice and BAFF transgenic mice both develop signs of human SLE. These findings that indicate inappropriate levels of TACI signaling may disrupt immune system balance, thereby promoting the development of autoimmune diseases. In this review, we summarize the basic characteristics of the TACI ligands BAFF and APRIL, and detail the research findings on the role of TACI in humoral immunity. We also discuss the possible mechanisms underlying the susceptibility of CVID patients with TACI mutations to autoimmune diseases and the role of TACI in the pathogenesis of SLE.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Autoimmune Diseases / immunology*
  • Autoimmunity / immunology
  • B-Cell Activating Factor / metabolism
  • B-Lymphocytes / cytology
  • B-Lymphocytes / immunology*
  • Cell Differentiation / immunology
  • Common Variable Immunodeficiency / genetics
  • Common Variable Immunodeficiency / immunology
  • Cytokines / immunology
  • DNA-Binding Proteins / metabolism
  • Humans
  • Immunity, Humoral / immunology*
  • Inducible T-Cell Co-Stimulator Ligand / metabolism
  • Mice
  • Positive Regulatory Domain I-Binding Factor 1
  • Repressor Proteins / metabolism
  • Signal Transduction
  • Transcription Factors / metabolism
  • Transmembrane Activator and CAML Interactor Protein / genetics
  • Transmembrane Activator and CAML Interactor Protein / metabolism*

Substances

  • B-Cell Activating Factor
  • Cytokines
  • DNA-Binding Proteins
  • ICOSLG protein, human
  • Inducible T-Cell Co-Stimulator Ligand
  • PDS5B protein, human
  • Repressor Proteins
  • TNFRSF13B protein, human
  • TNFSF13B protein, human
  • Tnfrsf13b protein, mouse
  • Transcription Factors
  • Transmembrane Activator and CAML Interactor Protein
  • PRDM1 protein, human
  • Positive Regulatory Domain I-Binding Factor 1