Fig. 2. Classical monocytes (CM) from SF3B1^K700E LR-MDS exhibit dysregulated immune gene expression and splicing.

A Metascape pathway and process enrichment analysis of up- and downregulated genes in peripheral blood CM from SF3B1^K700E LR-MDS (n = 3) compared to HD (n = 3). The top 10 and 20 representative terms are shown for up- and downregulated genes, respectively. B IPA core pathway analysis showing the predicted activity (cutoff z-score of >|0.5|) of overrepresented annotations (p-value < 0.05 [right-tailed Fisher’s exact test]) based on the list of DEG (PostFC ≥ 2 or ≤0.5, PPDE > 0.95) in SF3B1^K700E or SF3B1^wt compared to HD CM (n = 3 per group). C Alternative splicing (AS) signature in SF3B1^K700E CM: Volcano plot highlighting differentially spliced genes (DSG) with inclusion level difference (ILD) > |0.2| and pie chart showing distribution of differential splicing event types detectable in SF3B1^K700E LR-MDS compared to HD CM using rMATS. Shown below is the pathway and process enrichment analysis of DSG using Metascape (top 20 enriched terms across input DSG). D Cytokine secretion of LPS-stimulated CM was determined by Luminex analysis. Heatmap depicts Log2-transformed normalized median fluorescence intensity values for the indicated cytokines produced by HD, SF3B1^K700E, or SF3B1^wt (n = 3 per group) LR-MDS classical monocytes following in vitro LPS stimulation. The variant allele frequency (VAF) of SF3B1^K700E mutation in CM is shown on the left side. AS alternative splicing, A3SS alternative 3’ splice site, A5SS alternative 5’ splice site, DEG differentially expressed genes, DSG differentially spliced genes, MXE mutually exclusive exon, RI retained intron, SE skipped exon.