The violin chart showed 11 kinds of immune cells (B cell naive, B cell memory, T cell CD8+, T cell CD4+ memory resting, T cell regulatory (Tregs), Monocyte, macrophages M0/ M1/M2, Myeloid dendritic cell resting, activated Mast cells) that were present in significantly different proportions in HNSCC tissues (Fig. 9B). Here, CD4 is linked to head and neck squamous cell carcinoma.