lacks_plasma_membrane_part has plasma membrane part develops_from develops from develops from has high plasma membrane amount immature single positive thymocyte immature single positive T cell immature single positive T lymphocyte Note that this type of thymocyte has passed the beta-selection checkpoint and is rapidly proliferating and rearranging the T cell receptor alpha chain and expressing the CD8 coreceptor. This stage comes between the DN4 and DP stages. ISP T.ISP.th A thymocyte that has the phenotype CD4-negative, CD8-positive, CD44-negative, CD25-negative, and pre-TCR-positive. immature single positive T-lymphocyte DN4 thymocyte thymocyte pre-T cell receptor complex CD4 molecule CD44 molecule interleukin-2 receptor subunit alpha signal transducer CD24 T cell receptor co-receptor CD8