Effect of JAK2 V617F on leukocyte and platelet counts.

<div><p>(A) Peripheral blood leukocyte counts for the three cohorts in Balb/c and B6 backgrounds as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000018#pone-0000018-g001" target="_blank">Figure 1</a>.</p> <p>The difference in leukocyte counts between JAK2 V617F and JAK2 WT recipients was significant for the Balb/c cohort (<i>P</i> = 0.0039) but not for B6 (<i>P</i> = 0.0542, unpaired <i>t</i>-test).</p> <p>The hatched portion of the histogram represents the percentage of the total leukocyte count comprised by neutrophils.</p> <p>(B) Wright-Giemsa-stained cytospins of peripheral blood leukocytes from representative mice with BCR-ABL-induced CML-like MPD (left) or JAK2 V617F-induced PV-like MPD (right).</p> <p>Note the predominance of mature neutrophils and lack of immature myeloid elements (myelocytes and promyelocytes) in the JAK2 V617F recipient.</p> <p>(C) Platelet counts for the groups in (A).</p> <p>There was no significant difference in platelet counts between the three cohorts in either stain.</p> <p>(D) GFP fluorescence (left panels) and phase contrast images (right panels) of purified megakaryocytes from recipients of JAK2 V617F-transduced BM (top panels) or normal control mice (bottom panels).</p> <p>Note the GFP fluorescence in the majority of megakaryocytes from JAK2 V617F recipients.</p> <p>(E) Tail bleeding time (Balb/c cohort) for the three groups.</p> <p>The mean bleeding time (bar) of JAK2 V617F recipients was significantly longer than that of vector or JAK2 WT recipients (<i>P</i> = 0.0328 and <i>P</i> = 0.0002, respectively, unpaired <i>t</i>-test).</p>