<p>The present study compares transcript and protein regulation in peripheral blood of adult and juvenile dermatomyositis (DM) patients vs. healthy control subjects to identify novel pathways in active patients under treatment. Whole blood data is submitted representing transcript and protein expression, including 14 adult DM and 11 juvenile DM (JDM) patients, and 11 healthy pediatric controls. Whole blood RNA was examined using Affymetrix Human U133 Plus 2.0, and whole blood protein measurements were obtained using SOMAscan Assay v3.2 aptamer-based DNA probes.</p><p>Expression of 1,124 gene loci were significantly altered at the transcript or protein levels across DM or JDM, with 70 genes shared. A subset of interferon-stimulated genes was elevated. Innate immune markers specific to neutrophil granules and neutrophil extracellular traps were up-regulated in both DM and JDM. Pathway analysis revealed up-regulation of PI3K/AKT, ERK, and p38 MAPK signaling. Up-regulated components shared by DM and JDM included: cytokine:receptor pairs LGALS9:HAVCR2, LTF/NAMPT/S100A8/HSPA1A:TLR4, CSF2:CSF2RA, EPO:EPOR, FGF2/FGF8:FGFR; several Bcl-2 components; and numerous glycolytic enzymes. Pathways unique to DM included sirtuin signaling, aryl hydrocarbon receptor signaling, protein ubiquitination, and granzyme B signaling.</p>

Studies in the Natural History and Pathogenesis of Childhood-Onset and Adult-Onset Idiopathic Inflammatory Myopathies