In line with previous findings showing that neutralizing the acidification of the TME and/or increasing IFNγ production by CD8+ T cells enhances the response to immunotherapy in different tumors, such as melanoma and breast cancer5,10,56, we have demonstrated that inhibition of SLC4A4 can sensitize PDAC to ICB treatment, leading to complete or partial regression of orthotopic KPC tumors and longer survival, further underlining the therapeutic potential of SLC4A4 blockade. Here, SLC4A4 is linked to melanoma.