IL23A and infection: Whereas IL-23 is dispensable during primary infection with Mtb H37Rv [19], the expression of IL-23 is required for antimycobacterial protection after subunit vaccination with 6-kilodalton early secreted antigenic target protein (ESAT-6)1–20 adjuvanted by a combination of TDM, monophosphoryl lipid A (MPL), and dimethyl dioctadecylammonium bromide (DDA) [15].