| First Author | Sarafova SD | Year | 2009 |
| Journal | Immunity | Volume | 31 |
| Issue | 3 | Pages | 480-90 |
| PubMed ID | 19747858 | Mgi Jnum | J:152836 |
| Mgi Id | MGI:4360125 | Doi | 10.1016/j.immuni.2009.07.006 |
| Citation | Sarafova SD, et al. (2009) Upregulation of CD4 expression during MHC class II-specific positive selection is essential for error-free lineage choice. Immunity 31(3):480-90 |
| abstractText | The lineage fate of developing thymocytes is determined by the persistence or cessation of T cell receptor (TCR) signaling during positive selection, with persistent TCR signaling required for CD4 lineage choice. We show here that transcriptional upregulation of CD4 expression is essential for error-free lineage choice during major histocompatibility complex class II (MHC II)-specific positive selection and is critical for error-free lineage choice in TCR-transgenic mice whose thymocytes compete for the identical selecting ligand. CD4 upregulation occurred for endogenously encoded CD4 coreceptors, but CD4 transgenes were downregulated during positive selection, disrupting MHC II-specific TCR signaling and causing lineage errors regardless of the absolute number or signaling strength of transgenic CD4 proteins. Thus, the kinetics of CD4 coreceptor expression during MHC II-specific positive selection determines the integrity of CD4 lineage choice, revealing an elegant symmetry between coreceptor kinetics and lineage choice. |
