MYD88 and myositis disease: Based on the rapid time course of myositis development and the known dependence of this model on MyD88 signaling pathways, we sought to further define the role of innate immune responses in driving T cell infiltration following immunization with recombinant HRS (which we have previously shown can engage with endogenous/exogenous ligands to synergistically activate both TLR2 and TLR4 (13)).