Biology subjects

Marshak-Rothstein, A.

Publications and source records attributed to Marshak-Rothstein, A..

9 recordsLinked to original sources

bioRxiv2026

Macrophage-derived IL-27 sustains autoreactive CD8+ cytotoxic T cells in autoimmune hepatitis

Chronic or persistent T cell activation is widely thought to culminate in T cell exhaustion, yet how autoreactive CD8+ T cells remain functionally intact despite sustained self-antigen exposure is poorly understood. In chronic infection and cancer this durability is attributed to stem-like, TCF1+ PD-1+ progenitor-exhausted (Tpex) cells that reside in lymphoid tissue and continuously replenish functional effectors; whether such a reservoir operates within a chronically inflamed peripheral organ during sterile autoimmunity is unknown. Here we show that mice lacking the lysosomal nuclease DNase2a together with the type I interferon receptor Ifnar1 (Dnase2a-/- Ifnar1-/-) develop spontaneous, progressive hepatic inflammation. This hepatitis was dependent on the endosomal DNA sensor TLR9, identifying self-DNA as the initiating ligand. Inflammation was marked by expansion of inflammatory macrophages and accumulation of CD8+ T cells co-expressing PD-1 and TOX that retained, rather than lost, effector function. Paired single-cell TCR and transcriptomic analysis revealed progenitor-exhausted T cells within the liver itself that shared clonotypes with clonally expanded PD-1+ TOX+ T cells, defining a locally operating progenitor-to-effector pipeline. Spatial transcriptomics positioned these intrahepatic T cell clusters adjacent to IL-27-expressing inflammatory macrophages, and disruption of IL-27 or its receptor in bone marrow-derived cells reduced PD-1+ CD8+ T cells and their effector functions. These findings define a novel mechanism for sustaining autoreactive T cells in the liver via TLR9-driven macrophage-induced IL-27 circuit that sustains a functional, self-renewing autoreactive PD-1+ CD8+ T cell program in situ.

immunology↗

bioRxiv2025

Endothelial Cell Expression of STINGV154M Gain-of-Function Mutation Delays the Resolution of UVB-induced Skin Injury

Gain-of-function mutations in STimulator of INterferon Genes (STING) cause STING-Associated Vasculopathy with Onset in Infancy (SAVI), a rare autoinflammatory disease characterized by debilitating inflammatory lung disease and hallmark skin manifestations, such as chilblains and progressive, non-healing ulcers. Mice expressing the most common SAVI-associated variant STINGV154M (VM) recapitulate many clinical features of SAVI, including inflammatory lung disease, but do not develop spontaneous skin lesions. In this study, we show that a single low dose of ultraviolet B (UVB) irradiation, which induces only transient skin inflammation in wild-type (WT) mice, causes severe and progressive skin injury in VM mice. Notably, this phenotype persisted in VM mice depleted of hematopoietic cells and reconstituted with WT bone marrow, demonstrating that STINGV154M expression in non-hematopoietic cells is sufficient to drive persistent skin inflammation. Further analysis identified endothelial cells expressing STINGV154M as the primary driver of the cutaneous phenotype. Flow cytometry and bulk RNA sequencing showed that VM mice exhibited reduced early skin infiltration of macrophages and dendritic cells after UVB exposure. These findings establish a critical link between endothelial STING activation, impaired recruitment of skin myeloid cells, and defective resolution of acute inflammation, offering new insights into the pathogenesis of SAVI-associated skin disease.

immunology↗

bioRxiv2025

Secondary lymphoid organ stroma activate and elaborate regulatory T cells to suppress autoantibody production in a novel model of systemic autoimmunity

Preclinical models of lupus indicate that T cell-B cell collaboration drives pathogenic antinuclear antibody (ANA) production and sustains T cell activation. Mechanisms that normally limit T cell activation of autoreactive B cells remain incompletely resolved but potentially include the absence of autoreactive effector T cell subsets and/or the presence of autoantigen-specific regulatory T cells (Tregs). Several studies have addressed this issue by using experimental systems dependent on transgenic autoreactive B cells, but much less is known about the activation of autoreactive B cells present in a polyclonal repertoire. We have now explored the role of effector T cells and Tregs using mice that express an inducible pseudo-autoantigen on antigen presenting cells (APCs) including a normal B cell repertoire. Bone marrow chimera experiments demonstrated that radioresistant non-hematopoietic stromal APCs (rAPC) present in the thymus and in peripheral lymphoid tissue induced the differentiation and expansion of a subset of CD62L+CD69+ Tregs associated with decreased autoantibody production and MHC-II. In this study, we show that secondary lymph node stromal cells may be crucial for suppression of endogenous autoreactive B cells in the setting of robust T cell help.

immunology↗

bioRxiv2024

Two distinct durable human class-switched memory B cell populations are induced by vaccination and infection

Memory lymphocytes are durable cells that persist in the absence of antigen, but few human B cell subsets have been characterized in terms of durability. The relative durability of eight non-overlapping human B cell sub-populations covering 100% of all human class-switched B cells was interrogated. Only two long-lived B cell populations persisted in the relative absence of antigen. In addition to canonical germinal center-derived switched-memory B cells with an IgD-CD27+ CXCR5+ phenotype, a second, non-canonical, but distinct memory population of IgD-CD27- CXCR5+ DN1 B cells was also durable, exhibited a unique TP63-linked transcriptional and anti-apoptotic signature, had low levels of somatic hypermutation, but was more clonally expanded than canonical switched-memory B cells. DN1 B cells likely evolved to preserve immunological breadth and may represent the human counterparts of rodent extrafollicular memory B cells that, unlike canonical memory B cells, can enter germinal centers and facilitate B cell and antibody evolution. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=140 SRC="FIGDIR/small/624972v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@169c77forg.highwire.dtl.DTLVardef@1a872f5org.highwire.dtl.DTLVardef@1360cforg.highwire.dtl.DTLVardef@38d7ed_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2024

IFNγ initiates TLR9-dependent autoimmune hepatitis in DNase II deficient mice

Patients with biallelic hypomorphic mutation in DNASE2 develop systemic autoinflammation and early-onset liver fibrosis. Prior studies showed that Dnase2-/- Ifnar-/- double knockout (DKO) mice develop Type I IFN-independent liver inflammation, but immune mechanisms were unclear. We now show that DKO mice recapitulate many features of human autoimmune hepatitis (AIH), including periportal and interstitial inflammation and fibrosis and elevated ALT. Infiltrating cells include CD8+ tissue resident memory T cells, type I innate lymphoid cells, and inflammatory monocyte/macrophage cells that replace the Kupffer cell pool. Importantly, TLR9 expression by bone marrow-derived cells is required for the the development of AIH. TLR9 is highly expressed by inflammatory myeloid cells but not long-lived Kupffer cells. Furthermore, the initial recruitment of TLR9 expressing monocytes and subsequent activation of lymphocytes requires IFN{gamma} signaling. These findings highlight a critical role of feed forward loop between TLR9 expressing monocyte-lineage cells and IFNg producing lymphocytes in autoimmune hepatitis.

immunology↗

bioRxiv2023

Activation of Autoreactive Lymphocytes in the Lung by STING Gain-of-function Mutation Radioresistant Cells

Gain-of-function mutations in the dsDNA sensing adaptor STING lead to a severe autoinflammatory syndrome known as STING-associated vasculopathy with onset in Infancy (SAVI). SAVI patients develop interstitial lung disease (ILD) and commonly produce anti-nuclear antibodies (ANAs), indicative of concomitant autoimmunity. Mice heterozygous for the most common SAVI mutation, V154M (VM), also develop ILD, triggered by nonhematopoietic VM cells, but exhibit severe peripheral lymphopenia, low serum Ig titers and fail to produce autoantibodies. In contrast, we now show that lethally irradiated VM mice reconstituted with WT stem cells (WT[->]VM chimeras) develop ANAs and lung-reactive autoantibodies associated with accumulation of activated lymphocytes and formation of germinal centers in lung tissues. Moreover, when splenocytes from WT[->]VM chimeras were adoptively transferred into unmanipulated Rag1-/- mice, donor T cells accumulated in the lung. Overall, these findings demonstrate that expression of the VM mutation in non-hematopoietic cells can promote the activation of immunocompetent autoreactive lymphocytes. SummaryChimeric mice expressing STING only in non-hematopoietic cells develop systemic and lung directed autoimmunity which recapitulates what is seen in pediatric patients with SAVI disease.

immunology↗

bioRxiv2023

Expression of a STING Gain-of-function Mutation in Endothelial Cells Initiates Lymphocytic Infiltration of the Lungs

Patients afflicted with STING gain-of-function mutations frequently present with debilitating interstitial lung disease (ILD) that is recapitulated in mice expressing the STINGV154M mutation (VM). Prior radiation chimera studies revealed an unexpected and critical role for non-hematopoietic cells in the initiation of ILD. To identify STING-expressing non-hematopoietic cell types relevant to ILD, we generated a conditional knock-in (CKI) model in which expression of the VM allele was directed to hematopoietic cells, fibroblasts, epithelial cells, or endothelial cells. Only endothelial cell-targeted expression of the mutant allele resulted in the recruitment of immune cells to the lung and the formation of bronchus-associated lymphoid tissue, as seen in the parental VM strain. These findings reveal the importance of endothelial cells as instigators of STING-driven lung disease and suggest that therapeutic targeting of STING inhibitors to endothelial cells could potentially mitigate inflammation in the lungs of SAVI patients or patients afflicted with other ILD-related disorders. SummaryPatients with STING gain-of-function (GOF) mutations develop life-threatening lung autoinflammation. In this study, Gao et al. utilize a mouse model of conditional STING GOF to demonstrate a role for endothelial STING GOF in initiating immune cell recruitment into lung tissues of SAVI mice.

immunology↗

bioRxiv2023

Antigen receptor signaling and cell death resistance controls intestinal humoral response zonation.

Immunoglobulin A (IgA), the main antibody isotype found in the intestine, has evolved to maintain the stability of commensal communities, and prevent dysbiosis. In stark contrast to systemic antibody response against pathogens, the generation of IgA against intestinal resident microbes assures the simultaneous binding to multiple and diverse commensal-derived antigens. However, the exact mechanisms by which B cells mount such broadly reactive IgA response to the gut microbiome at the mucosal barrier remain elusive. Here we show surface IgA B cell receptor (BCR) is required to confer enhanced B cell fitness during the germinal center reaction in Peyers patches and to mediate selection of gut-homing plasma cells with higher efficiency. We demonstrate that, upon antigen stimulation, IgA+ BCR drives greater intracellular signaling in mouse and human B cells and as consequence, IgA+ B cells received higher positive selection cues in the germinal center. Mechanistically, in vivo IgA BCR signaling offsets Fas-mediated cell death to rescue low affinity B cell clones and redirects the humoral response to an increased variety of commensal strains at the intestinal interface. Our findings revealed a new mechanism linking tissue-specific antigen receptor signaling with B cell fate and localization of antibody production; and have implications for understanding how intestinal antigen recognition shapes humoral immunity in health and disease.

immunology↗

bioRxiv2022

IgD+ Age-Associated B cells are the progenitors of the main T-independent B cell response to infection that generates protective Ab and can be induced by an inactivated vaccine in the aged

Age-associated B cells (ABC) accumulate with age and are associated with autoimmunity and chronic infection. However, their contributions to acute infection in the aged and their developmental pathways are unclear. We find that the response against influenza A virus infection in aged mice is dominated by a Fas+GL7- effector B cell population we call infection-induced-ABC (iABC). Most iABC express IgM and include antibody-secreting cells in the spleen, lung and bone marrow. We find that in response to influenza, IgD+CD21-CD23-ABC are the precursors of iABC. These IgD+ABC develop in germ free mice, so are independent of foreign antigen recognition, suggesting they arise from an intrinsic age-associated developmental program. The response of ABC to influenza infection, resulting in iABC, is T cell independent and requires both extrinsic TLR7 and TLR9 signals. In response to influenza infection, IgD+ABC can induce a faster recovery of weight and higher total anti-influenza IgG and IgM titers that can neutralize virus. Immunization with whole inactivated virus also generates iABC in aged mice. Thus, in unimmunized aged mice, whose other B and T cell responses have waned, IgD+ABC are likely the naive B cells with the potential to become Ab-secreting cells and to provide protection from infection in the aged.

immunology↗