Rheumatoid Arthritis May Be Treated By Targeting Specific Receptor Protein

Role of a specific receptor protein in the immune response may serve as a potential therapeutic target in diseases like rheumatoid arthritis, as per a study at the Tokyo University of Science, published in the journal Nature Communications. Autoimmune diseases are typically caused when the body’s immune system incorrectly recognizes its proteins and cells as threats and starts attacking them. In rheumatoid arthritis, the immune cells attack the body's joint components and proteins, causing painful inflammation and even the destruction of bone.

one of the main immune cells involved in kick-starting against the pathogenesis of autoimmune diseases is dendritic cells (DCs). These cells are equipped with a variety of receptors on their surfaces, which can either amplify or suppress the immune response.

The T cell-interacting, activating receptor on myeloid cells-1 (TARM1), a member of the leukocyte immunoglobulin-like receptor family, is one among such receptor. It is involved in the activation of other immune cells such as neutrophils and macrophages. However its role in the pathogenesis of rheumatoid arthritis remains unexplored.

TARM1 Prtein as a Target Against Rheumatoid Arthritis

The study team was able to identify the genes that were overexpressed in various mouse models of arthritis that included TARM1. "Tarm1 expression is elevated in the joints of rheumatoid arthritis mouse models, and the development of collagen-induced arthritis (CIA) is suppressed in TARM1-deficient mice", says Professor Yoichiro Iwakura from Tokyo University of Science.

The TARM1-deficient mice showed suppressed immune system's response to type 2 collagen (IIC) – a protein crucial for the development of CIA (collagen-induced arthritis) that resembles rheumatoid arthritis and thus used as a model for this autoimmune arthritis.

The antigen-presenting ability of DCs in TARM1-deficient mice was also found to be impaired. The team was thereby able to demonstrate that TARM1 plays an important role in the maturation and activation of DCs through interaction with IIC.

Injecting the TARM1-inhibitory soluble TARM1 proteins into the knee of a mouse with CIA resulted in suppressed progression of CIA in the mouse. This confirms the finding that TARM1 inhibition is effective in weakening autoimmune arthritis.

"Because excess DC activation is suggested in many autoimmune and allergic diseases, our observations suggest that TARM1 is a good target for the development of new drugs to treat such diseases", says Prof. Iwakura.

The present study highlights the importance of TARM1 protein in a wide range of therapeutics against rheumatoid arthritis as well as other autoimmune and allergic diseases.

Source-Medindia