FIGURE 3.

In vivo expression of S100A8/S100A9 induces megakaryopoiesis. S100A8/S100A9 proteins were expressed in S100A9KO mice by in vivo electroporation of S100a8 and S100a9 plasmids. In control, mice were electroporated with empty vector. Mice were euthanized 14 days after the procedure. A, Number of MKs in the BM was counted using H&E-stained slides. Representative images and cumulative results are shown. Arrows indicate MKs. Magnification, 20x. Scale bar, 50 μm. B, Number of BM cells was determined by counting cells from two femurs per each mouse. C, Proportion of indicated BM cell populations was determined by flow cytometry. D, Proportion and absolute number of indicated BM cell populations are shown. E, Results of complete blood count are shown. Presented are individual values, mean, and SEM values. Statistics: two-tailed Student t test.