STING1 and STING-associated vasculopathy with onset in infancy: The scRNAseq performed for the first time on mononuclear cells (MNC) from the BM of SAVI patient carrying the novel mutation in STING, prior to initiation of JAK-inhibitor treatments, revealed dysregulated type I IFN and inflammatory pathways in all immune cell populations, including the most primitive HSC compartment, and highlighted a strong cell death response, especially in the T and B cells compartments, resulting in T cell cytopenia and a prevalence of naïve T cells in the circulation.