CD4 and head and neck squamous cell carcinoma: HPV-positive HNSCC exhibited enhanced and distinct pattern of immune activation to HPV-positive HNSCC, which included upregulation of genes associated with immune-associated processes, high infiltration rate of CD8+IFNγ+ T lymphocytes, Tc17 lymphocytes, naïve CD4+T lymphocytes, and myeloid DCs along with high level of production of chemokines CXCL9, CXCL10, CXCL12, CXCL17, and CXCL21 (Partlova et al., 2015; Chen et al., 2018).