However, except for expression of PD-1 by CD45− cells in the contralateral (untreated) tumor, GSNO administered i.t. appeared to exert negligible effects on expression of tumor immunogenicity markers including calreticulin (CRT), CTLA-4, PD-1, and PD-L1 (Fig. 2f–j and Supplementary Fig. 22). The gene discussed is CTLA4; the disease is neoplasm.