CYTOKINE PRODUCTION AND REQUIREMENTS DURING T-CELL DEVELOPMENT

Cytokines have been presumed to play an important role during T-cell d evelopment, but until recently formal proof has been missing. Most cyt okine-knockout mice show apparently normal intrathymic T-cell developm ent. The exception to this is IL-7, as both IL-7 and IL-7R alpha knock out mice show abnormally low thymic cellularity, making IL-7 the first cytokine shown to be necessary for normal intrathymic T-cell developm ent.