Single-cell multi-omics sequencing reveals the immunological disturbance underlying STAT3-V637M Hyper-IgE syndrome.

Hyper-IgE syndrome (HIES) is a primary immunodeficiency characterized by, among others, the excessive production of IgE and repetitive bacterial/fungal infections. Mutations in STAT3, a transcription factor that orchestrates immune responses, may cause HIES, but the underlying mechanisms are not fully understood. Here, we used multi-omic approaches to comprehensively decipher the immune disturbance in a male HIES patient harboring STAT3-V637M. In his peripheral blood mononuclear cell (PBMC) we found significant clonal expansion of CD8 T cells (with increased CD8 subunits expression, potentially enhancing responsiveness to MHC I molecules), but not in his CD4 T cells and B cells. Although his B cells exhibited a higher potential in producing immunoglobulin, elevated SPIC binding might bias the products toward IgE isotype. Immune checkpoint inhibitors, including CTLA4, LAG3, were overexpressed in his PBMC-CD4 T cells, accompanied by reduced CD28 and IL6ST (gp130) expression. In his CD4 T cells, integrative analyses predicted upstream transcription factors (including ETV6, KLF13, and RORA) for LAG3, IL6ST, and CD28, respectively. The down-regulation of phagocytosis and nitric oxide synthesis-related genes in his PBMC-monocytes seem to be the culprit of his disseminated bacterial/fungal infection. Counterintuitively, in his PBMC we predicted increased STAT3 binding in both naïve and mature CD4 compartments, although this was not observed in most of his PBMC. In his bronchoalveolar lavage fluid (BALF), we found two macrophage subtypes with anti-bacterial properties, which were identified by CXCL8/S100A8/S100A9, or SOD2, respectively. Together, we described how the immune cell landscape was disturbed in STAT3-V637M HIES, providing a resource for further studies.