IL6 and rheumatoid arthritis: Interestingly, it has been reported that patients receiving the IL-6R neutralizing mAb Actemra (tocilizumab) for rheumatoid arthritis show side-effects like an increase in body weight and marked hypercholesterolemia during the treatment period, which maybe a result of an inhibition of WAT browning in these patients who also have chronic IL-6 production.