IL37 and infection: Due to the roles of the IL-12/IL-23 pathway in protecting the host from pathogens, however, ustekinumab may result in unintended downstream consequences such as the development of new infections or reactivation of underlying infections (Trinchieri, 2003; Langrish et al., 2004; Tato and Cua, 2008; Shen and Chen, 2018).