UCX® and UCX®-ATMP characterization. (A) Population doubling rate and (B) cumulative population doublings of cells from passages 1 to 20. UCX®-ATMP propagated well, with growth rates ranging between 1.5 to 3.5 population doublings (PDs)/week presenting a considerable longevity in culture, allowing for very high cell expansion potential. The comparative control UCX®, grew at 3 - to 6 PDs/week until P20 and reached a maximum passage of P25 after 54 ± 10 PDs and 112 ± 21 days in culture. Flow cytometric analysis of ISCT defined mesenchymal stromal cell (MSC) markers of UCX® (A) and UCX®-ATMP (B) at passages 1, 10 and 20. The percentage of CD44 and CD31, common MSCs markers, was also determined. Results are represented as mean ± SEM.