Fig. 1: Screening for cytokines that enhance proT-cell differentiation and expansion.

a Summary of two-part screening experiment workflow. Cells were cultured in screening conditions from day 0–7 or cultured until day 7 and passaged at equal densities into test conditions and cultured until day 14. Cells from day 7 and 14 were harvested and analyzed using flow cytometry. The absolute count of each population of interest was measured and used to calculate a z-score relative to the 4F control. The z-scores were then used to fit multivariate linear regression models. b Effect of cytokines on total cells, CD7⁺ lymphocytes, and CD7⁺CD5⁺ cells. Red indicates an effect greater than the control condition while blue indicates an effect lesser than the control. The size of the circle indicates the significance of the effect in the regression model. From n = 2 independent UCB donors. c Histograms of CFSE stained cells showing the number of divisions of each cell on days 2–5. Separation of CD7⁻ and CD7⁺ histograms show differential responses to each cytokine. d Proliferation statistics from CFSE data. IL-3 treated cells had a larger proliferative index indicating that they underwent, on average, more divisions than the control group. They also had a significantly larger proliferative indicating that some cells responded much stronger to IL-3 than others. *p < 0.05 relative to the control on each day. e All groups transitioned through a proT1 to proT2 phenotype as expected during T-cell development. Results are mean ± standard error from n = 4 independent UCB donors.