CTSB and infection: Furthermore, our report suggests that active cholera toxin may be required to stimulate the posttranscriptional regulation of IL-23 via cathepsin B. While further work is needed to confirm that this in vitro finding is functionally significant, the stimulation of IL-23 production through existing or novel vaccine adjuvants should be explored as a potential mechanism to replicate responses to natural infection and achieve longer-term mucosal immunity through vaccination.