Important transcriptional activator in the regulation of genes involved in immune and inflammatory responses. Specifically binds to an IL-1 response element in the IL-6 gene. NF-IL6 also binds to regulatory regions of several acute-phase and cytokines genes. It probably plays a role in the regulation of acute-phase reaction, inflammation and hemopoiesis. The consensus recognition site is 5'-T[TG]NNGNAA[TG]-3'. Functions in brown adipose tissue (BAT) differentiation.