Although it is unclear whether the mechanism by which lactobacilli increase response to ICI is microbiota change or metabolite, there have been a number of reports in recent years that lactobacillus species can enhance reactivity to ICI30,31。Moreover, it was recently reported that Bifidobacterium pseudolongum produced inosine-activated Th1 cells with anti-tumor effects in the presence of IFN-γ or other costimulation31. Here, IFNG is linked to neoplasm.