STAT-3 is necessary for IL-27-mediated macrophage suppression but does not represent a therapeutic target for <i>E. coli</i> -induced neonatal sepsis

The neonatal period is a time in which newborns have increased vulnerability and the highest risk of death from infection. This includes sepsis for which there is a considerable global burden of disease. We have determined that the cytokine interleukin (IL)-27 is expressed at elevated levels in the first days of life and continues to rise during experimental bacterial neonatal sepsis. Neonatal mice that cannot respond to IL-27 exhibit improved outcomes. In this work, we have investigated the influence of STAT-3 on control of bacteria and inflammation during IL-27 signaling in neonates. It is critical that we understand mechanisms that underlie neonatal susceptibility to infection so that we can identify new targets for therapeutic intervention. Here, we define the value of STAT-3 in approaches to targeted therapies for bacterial neonatal sepsis.