New Mouse Model Unveils Autoimmune T Cell Involvement in Checkpoint Inhibitor-Induced Myocarditis

Immune checkpoint inhibitors (ICI) are medications used to treat a variety of cancers by targeting proteins such as PD-1 or CTLA-4 on cells. These proteins normally prevent the immune system from attacking healthy cells by sending an “off” signal to the immune cells. However, cancer cells often misuse this process to escape the immune system. ICIs block this “off” signal and enable the immune system to attack cancer cells.

However, many patients on these medications develop immune-related adverse events because the immune system cannot be turned off as usual. One rare, but serious side effect is myocarditis, which is fatal in 40% of cases. Understanding why this side effect happens and how it can be prevented is critical. 

Scientists supported by The Global Autoimmune Institute, tackled this issue and developed a new mouse model of myocarditis. Using these mice, they discovered that the amount of autoimmune T cells increased, leading to an attack on cardiac muscle. 

With this new mouse model, researchers are better equipped to study ways of preventing ICI-induced myocarditis in patients. 

Citation:

Won, T., et al. (2022). Cardiac myosin-specific autoimmune T cells contribute to immune-checkpoint-inhibitor-associated myocarditis. Cell Reports, 41(6), Article 111611.