title: Selection and lineage specification in the thymus: commitment 4-stalled.
abstract: How CD4(+)CD8(+) thymocytes commit to CD4 helper versus CD8 cytotoxic lineages is a central unresolved question in developmental immunology. In this issue, show that engineering CD4 for shutoff immediately after positive selection misdirects cells to the cytotoxic lineage. The result highlights the distinction between positive selection and lineage commitment and provides new impetus for reexamining lineage models.
authors.affiliation: Howard Hughes Medical Institute, Molecular Pathogenesis Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, 540 First Avenue, New York, New York 10016, USA. collins@saturn.med.nyu.edu
authors.forename: Amélie
authors.initials: A
authors.lastname: Collins
authors.forename: Dan R
authors.initials: DR
authors.lastname: Littman
mesh_terms: D000818:Animals; D015704:CD4 Antigens / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D019070:Cell Lineage / Q000235:genetics; D051379:Mice; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000254:growth & development / Q000276:immunology*
chemical_list: D015704:CD4 Antigens