The antigenic landscape of autoimmune diabetes reflects a failure to preserve self-tolerance, yet how novel neoantigens emerge in humans remains incompletely understood. Here we designed an immunopeptidomics-based approach to probe HLA-II-bound, islet-derived neoepitopes in patients with type 1 diabetes. We uncovered a Cys→Ser transformation, conserved between mice and humans...
Natural killer (NK) cells are innate lymphocytes known for their ability to kill infected or malignant cells, but they have an overlooked role in regulating antibody responses. In mice, NK cells can kill T follicular helper (TFH) cells, decreasing somatic hypermutation and antibody titers. Although human NK cell activation correlates with poor vaccine response, the mechanisms of...
Group 2 innate lymphocytes (ILC2s) are prevalent in small intestine but their role during homeostasis is unclear. Here we show that thymic stromal lymphopoietin (TSLP)—a cytokine implicated in ILC2 activation—is expressed constitutively in subepithelial fibroblasts, including telocytes and crypt-associated trophocytes, which are specialized fibroblasts necessary to sustain...
Oral immunotherapy (OIT) is the only U.S. Food and Drud Administration-approved treatment for peanut allergy. Peanut-reactive (pr) CD4+ T cells are pivotal in peanut allergy pathogenesis and OIT-induced desensitization. However, the underlying pr CD4+ T cell immune mechanisms leading to sustained unresponsiveness after OIT discontinuation are largely unknown. We analyzed single...
The long-term impact of systemic hypoxia resulting from acute respiratory distress syndrome (ARDS) on the function of short-lived innate immune cells is unclear. We show that patients 3–6 months after recovering from ARDS have persistently impaired circulating neutrophil effector functions and an increased susceptibility to secondary infections. These defects are linked to a...
MEF2C encodes a transcription factor that is critical in nervous system development. Here, to examine disease-associated functions of MEF2C in human microglia, we profiled microglia differentiated from isogenic MEF2C-haploinsufficient and MEF2C-knockout induced pluripotent stem cell lines. Complementary transcriptomic and functional analyses revealed that loss of MEF2C led to a...
Current influenza vaccines face challenges due to antigenic evolution of the circulating virus and waning immunity in humans. Here we investigated the durability of humoral immunity induced by an influenza vaccine based on AS03-adjuvanted chimeric hemagglutinin (cHA) in nonhuman primates (NHPs). Two groups of NHPs received two doses of a seasonal quadrivalent influenza vaccine...
The co-inhibitory receptor TIGIT suppresses excessive immune responses in autoimmune conditions while also restraining antitumor immunity. In viral infections, TIGIT alone does not affect viral control but has been shown to limit tissue pathology. However, the underlying mechanisms are incompletely understood. Here we found TIGIT+ T cells to express not only an immunoregulatory...
Regulatory T (Treg) cells, expressing the transcription factor Foxp3, are obligatory gatekeepers of immune responsiveness, yet the mechanisms by which Foxp3 governs the Treg transcriptional network remain incompletely understood. Using a novel chemogenetic system of inducible Foxp3 protein degradation in vivo, we found that while Foxp3 was indispensable for the establishment of...
The Foxp3⁺ regulatory T (Treg) cell repertoire carries age-dependent biases, with neonatal subsets enriched for highly self-reactive clones. However, the thymocyte features distinguishing neonatal from adult Treg selection remain unclear. Here, we show that neonatal double-positive mouse thymocytes, unlike their adult counterparts, fail to upregulate Zap70 during thymic selection...
Administration of HIV-1 neutralizing antibodies can suppress viremia and prevent infection in vivo. However, clinical use is challenged by envelope diversity and rapid viral escape. Here, we performed single B cell profiling of 32 top HIV-1 elite neutralizers to identify broadly neutralizing antibodies with highest antiviral activity. From 831 expressed monoclonal antibodies, we...
Rapidly progressive glomerulonephritis (RPGN) is the most aggressive group of autoimmune kidney diseases and is characterized by glomerular crescent formation with proliferation of parietal epithelial cells (PECs). However, the underlying mechanisms of glomerular crescent formation are incompletely understood. Here we provide a high-resolution spatial kidney cell atlas of 57...
Plasmacytoid dendritic cells (pDCs) are major producers of type I/III interferons. As interferons are crucial for antiviral defense, pDCs are assumed to play an essential role in this process; however, robust evidence supporting this dogma is scarce. Genetic or pharmacological manipulations that eliminate pDCs or disrupt their interferon production often affect other cells...
Fibroblasts sculpt the architecture and cellular microenvironments of various tissues. Here we constructed a spatially resolved atlas of human skin fibroblasts from healthy skin and 23 skin diseases, with comparison to 14 cross-tissue diseases. We define six major skin fibroblast subtypes in health and three that are disease-specific. We characterize two fibroblast subtypes...
Innate lymphoid cells (ILCs) are tissue-resident lymphocytes specialized in cytokine secretion that lack antigen-specific receptors. The contribution of ILCs to antiviral mucosal immunity in humans, particularly in the female genital tract (FGT), remains unexplored. Here we resolved human FGT ILC diversity by spectral flow cytometry and CITE-seq, spatial location within genital...
The formation of membrane pores by cleaved N-terminal gasdermin D (GSDMD-NT) results in the release of cytokines and inflammatory cell death, known as pyroptosis. Blocking GSDMD-NT pores is an attractive and promising strategy for mitigating inflammation. Here we demonstrate that SK56, an artificial intelligence-screened peptide, effectively obstructs GSDMD-NT pores and inhibits...
Interleukin-18 (IL-18) is an acute-phase proinflammatory molecule crucial for mediating viral clearance by activating T helper 1 CD4+ T cells, cytotoxic CD8+ T cells and natural killer (NK) cells. Here, we show that mature IL-18 is generated in the thymus following numerous distinct forms of tissue damage, all of which cause caspase-1-mediated immunogenic cell death. We report...
CD4+ T follicular helper (TFH) cells support tailored B cell responses against multiple classes of pathogens. To reveal how diverse TFH phenotypes are established, we profiled mouse TFH cells in response to viral, helminth and bacterial infection. We identified a core TFH signature that is distinct from CD4+ T follicular regulatory and effector cells and identified pathogen...
Crohn’s disease pathology is modeled in TNFΔARE+/− mice that overproduce tumor necrosis factor (TNF) to drive disease through TNF receptors. An alternative ligand for TNF receptors, soluble LTα3, is produced by B cells, but has received scarce attention because LTα also partners with LTβ to generate membrane-tethered LTαβ2 that promotes tertiary lymphoid tissue—another feature of...