We first synthesized STINGa ADCs with wildtype (wt) human IgG1 antibodies against two internalizing antigens on cancer cells, HER2 (ERBB2) and NaPi2b (SLC34A2)30,31; the wt antibodies/ADCs have the ability to engage with both their target antigens on tumor cells and FcγRs on myeloid cells (Fig. 1b, Supplementary Fig. 2). Here, SLC34A2 is linked to cancer.