Overexpression of SOCS-1 impairs T-cell differentiation from committed thymic precursors.

Fetal thymic lobes were infected with the indicated retrovirus constructs for 3 days and subsequently cultured for a further 1, 3, or 6 days. Single-cell suspensions were obtained from fetal thymic lobes at the indicated time and analyzed for surface expression of CD4 and CD8; percentages of cells in each quadrant are shown. The analysis was confined to infected donor cells by gating on GFP expression, as indicated by the rectangular gate in the GFP versus forward light scatter (FSC) dot plots; cell counts for the absolute number of GFP⁺ cells per lobe are shown in parentheses. Data obtained with uninfected (GFP⁻) cells are provided as a control for the ability of the thymic lobes to sustain normal T-cell development.