Microbiology Interleukin 1 (IL-1) is a potent cytokine. It is best described by which one of the following statements? A Synthesis of IL-1 is inhibited in activated macrophages B It can be produced by natural killer cells C It exerts its effects on T and B cells as a costimulator D It is multimeric and consists of more than one protein 💡 Explanation Interleukin 1 (IL-1) is a potent cytokine. It is best described by which one of the following statements? ✓ Correct Answer: B. It can be produced by natural killer cells