In addition to direct CLL-T cell inhibitory interactions, there is also a third-party immunomodulatory effect mediated by the expansion of CD4+/CD25hi/FOXP3+/CD127dim/− Tregs in the CD4+ subset, which contribute to suppressing host immune response by targeting other immune cells functions [33,34]. This evidence concerns the gene CD4 and B-cell chronic lymphocytic leukemia.