Fig. 2: Phenotype analysis and in vitro MK differentiation of Hoxa7-TPO cells.

a Phase contrast images of in vitro differentiated Hoxa7-TPO and BM cells cultured in the presence of TPO in the absence of exogenous estrogen for 4 and 6 days, respectively. b May-Grünwald-Giemsa staining of Hoxa7-TPO and BM cells described in (a). c Flow cytometry analysis of Hoxa7-TPO cells that were left non-differentiated (light grey) or were differentiated for 4 days in the presence of TPO using the DNA dye Hoechst H33342. d Phase contrast image of in vitro differentiated Hoxa7-TPO cells cultured in the presence of TPO in the absence of exogenous estrogen for 7 days. Proplatelets are indicated by blue arrows. e Differential interphase contrast (DIC) image of in vitro differentiated Hoxa7-TPO cells in the presence of TPO highlighting proplatelet formation (blue arrows). f Quantification of proplatelet-producing MK described in e in comparison to BM-derived MK, which were differentiated in the presence of TPO for 4 days and enriched by BSA-gradient. Data represent n = 6 independent experiments for Hoxa7-derived MK and n = 5 for BM-derived MK. Purple triangles and diamonds indicate independently established Hoxa7-TPO populations. Ns, not significant; Two-tailed unpaired t test. Source data are provided as a Source Data file. g, h Flow cytometry analysis of in vitro differentiating Hoxa7-TPO cells in the presence of TPO using antibodies against CD41 and CD42d (g) and the DNA dye Hoechst 33342 (h). Light gray, non-differentiated cells; dark grey, differentiating cells. i, j Phase contrast (i)- and May-Grünwald-Giemsa (j)-based microscopy images of in vitro differentiating Hoxa7-TPO cells in the presence of TPO. Magnification 20x. Scale bars (a, b, d, e, i, j) = 20 μm.