CD4 and breast neoplasm: CCL5 mediates breast tumor progression and recurrence by interacting with the CCR3 axis (Yamaguchi et al., 2021), recruiting macrophages (Walens et al., 2019) and regulating the CD4+/CD8+, CCR5+/CD4+ or Treg/CCR5+ cell ratios (Qiu et al., 2022).