CD4 and colorectal cancer: In order to characterize the landscape of B lymphocytes within the tumor microenvironment of colorectal cancer patients, the majority of studies focused on identifying TIBLs either in isolation or as part of a broader “immune hub” comprising TIBLs in association with T cells (CD4+, CD8+, FOXP3+, CD45RO+), dendritic cells (CD11c+), and macrophages (CD68+).