IL6R and congenital rubella syndrome: In sharp contrast, 16 out of the 18 patients (Fig. 2a, b) treated with CART-aIL6/IL1RA consistently displayed low levels of serum IL6 (< 100 pg/mL) during CRS, whereas the IFNG peaks varied a lot from very low levels to extremely high levels (ranging from 2.63 to 4118.03 pg/mL).