IL2 and allergic disease: 2/10 patients: chills with fever, possibly due to lymphokine release syndrome (13)2/10 patients: urticaria, 1/2 with severe allergic reaction possibly triggered by keeping a rodent as a pet, patient withdrawn from study (13) Chills, tremor, elevated body temperature, and nausea (15) Systemic side effects correlated with elevated levels of TNF-α, IL-2, and IFN-γ (15)5/10 patients: HAMA production after 1st treatment cycle → of these 3/4 showed HAMA production after 2nd treatment cycle (16)