Modelling the human IL6RA Asp358Ala variant in mice: effects on atherosclerosis and abdominal aortic aneurysm

The association of IL6RA Asp358Ala variant with reduced risk of atherosclerotic cardiovascular disease (ASCVD) and abdominal aortic aneurysm (AAA) prompted interest in targeting IL6 signalling in these conditions. A recent report that ziltivekimab, a neutralising anti-IL6 antibody, did not reduce major adverse cardiovascular events in patients with ASCVD and chronic kidney disease, has cast doubt on the causal role of IL6 signalling in ASCVD. Here, we show that introducing the orthologous IL6RA Glu357Ala substitution in male mice leads to the same alteration in soluble IL6RA levels seen in humans, and significantly prevents atherosclerosis and AAA. Thus, therapies that more closely reproduce the biological effects of the IL6RA Asp358Ala variant on IL6 signalling are needed to reduce cardiovascular risk in humans.