Figure 1. Production of Megakaryocytes by Expansion and Lineage-Specific Differentiation of CD34⁺ Human Cord Blood Cells Cultured in StemSpan™ SFEM Containing Megakaryocyte Expansion Supplement

Flow cytometry dot plots showing expression of the hematopoietic stem and progenitor cell marker CD34 and megakaryocyte markers CD41a and CD42b (A) before and (B,C) after culture of CD34⁺ cord blood cells for 14 days in StemSpan™ SFEM containing Megakaryocyte Expansion Supplement. The frequency of CD34⁺ cells declined from 90% before culture to <3% after 14 days, in parallel with a gradual accumulation of CD41a⁺CD42b⁺ megakaryocytes from 80% before and after culture, respectively.

Table 1. Production of Megakaryocytes from CD34⁺ Human Cord Blood Cells Cultured in StemSpan™ SFEM Containing Megakaryocyte Expansion Supplement

Numbers and percent of CD41a⁺ cells produced after 14 days of culture of enriched CD34⁺ cells from 6 independent cord blood (CB) samples. *95% confidence limits, the range within which 95% of the results will typically fall.

Figure 2. Comparison of Megakaryocyte Expansion in Different StemSpan™ Media Containing Megakaryocyte Expansion Supplement

(A) Average numbers and (B) frequencies of CD41⁺ megakaryocytic cells normalized relative to the values obtained in StemSpan™ SFEM (grey bars) after culturing purified CD34⁺ cord blood cells (n=6) for 14 days in StemSpan™ SFEM, SFEM II (blue bars) and AOF (orange bars) media containing Megakaryocyte Expansion Supplement. Vertical lines indicate 95% confidence limits, the range within which 95% of results typically fall. *The numbers of CD41a⁺ cells were significantly higher in SFEM II (p<0.01, paired t-test, n=6) compared to SFEM and AOF medium.

Note: Data for StemSpan™-AOF shown were generated with the original phenol red-containing version StemSpan™-ACF (Catalog #09855). However internal testing showed that the performance of the new phenol red-free, cGMP-manufactured version, StemSpan™-AOF (Catalog #100-0130) was comparable.