develops from develops from DN3 thymocyte DN4 thymocyte early cortical thymocyte T.DN4.th DN4 immature T-cell DN4 cell DN4 alpha-beta immature T-lymphocyte A thymocyte that has the phenotype CD4-negative, CD8-negative, CD44-negative, CD25-negative, and pre-TCR-positive. DN4 immature T cell Note that this type of thymocyte has passed the beta-selection checkpoint and is rapidly proliferating and beginning to rearrange the T cell receptor alpha chain. There is growing evidence that molecular markers characterizing double negative thymocytes are different across species, especially in mouse versus human thymus. If in doubt, please consider using CL:0002489 'double negative thymocyte'. double negative 4 DN4 alpha-beta immature T lymphocyte double negative thymocyte