Zhang et al.99 used a vesicular nanoparticle (VNP) system to deliver siLdha to tumor sites to knock down lactate dehydrogenase (LDHA), which plays a key role in lactate production, to reduce lactate production, reverse the acidic microenvironment of tumors, restore T cell anti-tumor function, and enhance the therapeutic effect of the immune checkpoint inhibitor, PD-1 antibody (Figure 5C). The gene discussed is LDHA; the disease is neoplasm.