ROLE OF THE LIVER IN T-CELL DIFFERENTIATION-GENERATION OF CD3(-)CD4(+) CD8(+)TCR-BETA(-) CELLS AND CD3(-)4(-)8(-)TCR-BETA(+) CELLS FROM CD4(-)8(-)TCR-BETA(-) ATHYMIC NUDE BONE-MARROW CELLS BY CULTURE WITH PARENCHYMAL LIVER-CELLS/

To investigate the influence of the Liver on differentiation of hemato poietic stem cells/pro-T cells, TN-NWP-BMC (athymic nude bone marrow c ells that were treated with anti-TCR beta, anti-CD4, and anti-CD8 Abs plus complement and then passed through a nylon wool colunm) were cult ured on parenchymal liver cells. After culture for 2.5 days, CD3(-)4(- )8(-)TCR beta(+) cells and CD3(-)CD4(+)/CD8(+)TCR beta(-) cells were d eveloped from TN-NWP-BMC. TCRV beta 8(+) cells comprised 19.9% of CD3( -)4(-)8(-)TCR beta(+) cells, and V beta 8 mRNA was detected in the CD3 (-)4(-)8(-)TCR beta(+) cells by reverse transcriptase-polymerase chain reaction, The CD3(-)CD4(+)/CD8(+) TCR beta-cells contained not only s ingle-positive cells but also CD4(+)8(+) double-positive cells. The CD 8 protein consisted of 88.9% CD8 alpha(+)beta(-), 10.1% CD8 alpha(+)be ta(+), and 1% CD8 alpha(-)beta(+) molecules. From these results and th e finding of co-expressed antigens, CD3(-)4(-)8(-)TCR beta(+) cells an d CD3(-)CD4(+)/CD8(+)TCR beta(-) cells appear to be immature cells not committed to a certain cell lineage.