Using the NK-92 cell line transduced with CD19 (FMC63 scFv) or PD-L1 (atezolizumab-based scFv) CARs, we found that ammonia suppressed the cytotoxicity of NK-92 CAR cells against Raji (Fig. 3F) and MDA-MB-231 breast cancer cells (Fig. 3G), respectively. Here, CD274 is linked to breast cancer.