Fig. 4

Relationship between IL-1β and IL-6 and megakaryocyte output. Plasma levels of (A) IL-1β and (E) IL-6 in myelofibrosis (MF, n = 30), essential thrombocythemia (ET, n = 16) and control (n = 10) samples quantified by ELISA, were plotted. Kruskal–Wallis followed by Dunn’s multiple comparisons test. Bars and error bars indicate the median and interquartile range. MF patients were grouped according to the MIPSS70 score and levels of plasma (B) IL-1β and (F) IL-6 were plotted. Kruskal–Wallis followed by Dunn’s multiple comparisons or Mann Whitney test (IL1β, low + intermediate vs. high risk group). Bars and error bars indicate the median with interquartile range. Spearman correlation between (C) IL-1β or (G) IL-6 and megakaryocyte (MK) count. Inhibition of megakaryopoiesis in MF plasma samples. IL-1β and IL-6 were blocked in plasma using specific antibodies prior to the addition of MF plasma samples to day 6 MK culture. At day 12, cells were counted in a Neubauer chamber. MF samples (n = 7) were incubated with blocking (D) IL-1β or (H) IL-6 (50 µg, +) antibodies and compared to the same plasma samples without previous incubation with the corresponding antibody (-). Wilcoxon test.