Novel insights into Tim-4 function in autoimmune diseases

Abstract

T-cell immunoglobulin domain and mucin domain-4 (Tim-4) was first recognized as a costimulatory molecule regulating T-cell activation. Dysregulation of Tim-4 has been found in some autoimmune conditions, particularly in the immune cells. Recently, Tim-4 was found to be critical for regulating T cells, with the ability of inhibiting naïve CD4⁺ T cells and Th17 cells, increasing Th2 cell development. Tim-4 can also enhance T cell expansion via linker for activation of T cells, extracellular signal-regulated kinase (ERK) and Protein kinase B (PKB, also known as Akt) signaling pathways. Moreover, the Tim-4 signaling pathway may affect multiple molecular processes in autoimmune diseases. A number of previous studies have demonstrated that Tim-4 influences chronic autoimmune diseases, such as rheumatoid arthritis (RA) and systemic lupus erythematosus. In addition, an association between Tim-4 polymorphisms and susceptibility to several autoimmune diseases have been identified, such as RA. Taken together, recent works have indicated that Tim-4 may represent a novel target for the treatment of autoimmune diseases. In this article, we will discuss the Tim-4 function and the therapeutic potential of modulating the Tim-4 in autoimmune diseases.

• Autoimmune diseases
• RA
• SLE
• target
• Tim-4

Declaration of interest

The authors declare no conflict of interests. The authors are responsible for the content and the writing of this paper.

This work was supported by grants from the National Natural Science Foundation of China (81172764, 81102192) and the Specialized Research Fund for the Doctoral Program of Higher Education of China (20113420120008).