Researchers develop mathematical model to explain rheumatoid arthritis treatment resistance

Researchers at Soonchunhyang University Bucheon Hospital have developed a mathematical model to explain why some patients with autoimmune diseases, such as rheumatoid arthritis and lupus, do not respond to standard treatments. The study, published in npj Systems Biology and Applications, suggests that treatment resistance is not caused by a single inflammatory pathway, but is a result of complex interactions between multiple biological systems.

The team developed the ‘3-Axis Integrative Framework (3-AIF)’, which simulates the interactions between three biological axes: intestinal mucosa/microbes/immune tolerance, nerves/adipose tissue/immune cells, and cell metabolism/stress response. Through simulations, the researchers found that the body can exist in several stable states, including healthy, sub-remission, chronic active disease, and treatment-resistant states.

The model also identified a phenomenon known as ‘hysteresis’, where once a body transitions from a healthy state to a disease state, simply reducing the initial trigger is often insufficient to return to health. This highlights the critical importance of early diagnosis and intervention. Notably, the study found that the vagus nerve, which regulates inflammation through the parasympathetic nervous system, is a key factor in determining disease states.