Combining high-concentration NO and immune checkpoint inhibitors warrants further assessment especially in tumors resistant to checkpoint inhibitor therapy.
Intra-tumoral injection of ultra-high doses of NO at 20,000 and 50,000 ppm gNO led to an increased recruitment and concentration of T and B cells. Additionally, 50,000 ppm NO led to an increase of lymphocyte infiltration to the tumor. Taken together, the data suggest that the increase in lymphocyte infiltration, B and T cell population, and the reduction of MDSCs, are indicative of an adaptive immune response that results in rejection of secondary tumors in gNO-treated mice.