By lowering huntingtin expression, the myeloid cell function was normalized.17 Human HD monocytes exhibit transcriptional differences, such as increased IL-6 expression under both basal and stimulated conditions.38 In human HD as well as in HD mouse models, monocytes and macrophages show increased activation and likely contribute to the increased levels of cytokines detected in blood and CSF.39 Both peripheral and CNS immune system activity has been shown to increase with disease progression in HD mouse models. Here, HTT is linked to Huntington disease.