Autoregulatory effects of interleukin 1 on human monocytes

Interleukin 1 (IL 1) is a cytokine which was initially defined as an immunologically nonspecific monocyte/ macrophage-derived factor that enhances the proliferative response of murine thymocytes (1). In this article we will briefly review recent information concerning the formation and properties of IL 1. In addition, we will present data suggesting that IL 1 may be an autostimulating signal for human monocytes.