This immunophenotyping corroborated the Ly6G staining results on primary tumor sections, as chitin treatment in combination with or without anti-PD-1 significantly reduced both the number and percentage of TANs in the 4T1- and the number of TANs in the 66cl4-based model (Fig. 5A,B, Additional file 10: Fig. S8A,B). The gene discussed is PDCD1; the disease is neoplasm.