Characterization of UCB T-cells expanded by CLL-APC.

<p>A. UCB cell products expanded by CLL-APC consisted almost entirely of CD3⁺ cells with very few contaminating CD3⁻CD56⁺ cells. CD3⁺ cells upregulated CD127 from undetectable levels pre-stimulation, indicating a memory phenotype. Error Bars = +/−SD. CD45RA and CD28 were also significantly downregulated among expanded T-cells. Following three stimulations with CLL-APC, expanded UCB lymphocytes were spectratyped to determine Vβ repertoire polyclonality in comparison to the naïve, unstimulated fraction. B. Vβ locus spectratype distribution of naïve, unstimulated lymphocytes. C. Vβ locus spectratype distribution of stimulated, expanded lymphocytes. One of seven experiments shown. Note that repertoire polyclonality is maintained.