A joint study by Korean researchers has figured out a primary mechanism that causes rheumatoid arthritis (RA), raising the disease's understanding.
The researchers found the mechanism that the genetic variation of the disease’s causes in the key cells that play a crucial role in causing RA is also essential for changing gene expression. They then found 11 causative genes related to developing RA for the first time in the world through the precise analysis of 300,000 people in various racial and ethnic groups.
Conducting the joint research were researchers at Hanyang University Medical Center (HYUMC) led by Professor Bae Sang-Cheol, researchers at Kyung Hee University led by Professor Kim Gwang-woo, and the Korea Disease Control and Prevention Agency, HYUMC said Wednesday.
The CD4T cells, which have been found to play the most important role in causing RA, are core cells that perceive the non-self-antigen in the adaptive immunity and are activated, which leads to stimulating an immune response. Suppose a CD4T cell reacts to self-antigen. In that case, it develops autoimmune diseases, such as RA, in which CD4T cells are activated, attacking the joints and major parts of the body, causing inflammation.
The study showed that gene expression patterns in patients with RA differed significantly compared to healthy groups and proved that many genes are controlled by methylation of the DNA. Besides, researchers found DNA methylation is determined by genetic variations causative to RA.
The team concluded that the overall mechanism of RA is controlled by post-genetic differences caused by genetic variation. By finding the 11 new genes, the team identified that CD4 T cells activated or CD4 T cells segmented from Th17 cells play a significant role in the RA's occurrence.
“We have found 11 new genes, related to RA through a largest-scale of RA study, and discovered the importance of CD4 T cells in the occurrence of RA and could understand the mechanism behind occurring RA,” Professor Kim said.
Professor Bae also said, “We have identified that gene mutations inside CD4 T cells control the associated genes through DNA methylations, and will further develop the disease prevention and precision medicine.”
The study was published in the latest issue of Annals of the Rheumatic Diseases.