CD4 and neoplasm: Notably, the capacity of ICD to activate an efficient immune response is limited by tumour microenvironment (TME) components, such as infiltration by CD4+ CD25+ FOXP3+ regulatory T-cells (Tregs), which promote immunosuppression through cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression and interleukin-10 (IL-10) release, and tumour fibrotic response, which is particularly significant in pancreatic ductal adenocarcinomas (PDACs) and alters-primed T-cell lymphocytes mobility [32,33].