ABSTRACT
Delayed-type drug hypersensitivity reactions are major causes of morbidity and mortality. The origin, phenotype, and function of pathogenic T cells across the spectrum of severity require investigation. We leveraged recent technical advancements to study skin-resident memory T cells (TRMs) versus recruited T cell subsets in the pathogenesis of severe systemic forms of disease, Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS), and skin-limited disease, morbilliform drug eruption (MDE). Microscopy, bulk transcriptional profiling, and single-cell RNA-sequencing (scRNA-Seq) plus cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq) plus T cell receptor sequencing (TCR-Seq) supported clonal expansion and recruitment of cytotoxic CD8+ T cells from circulation into skin along with expanded and nonexpanded cytotoxic CD8+ skin TRM in SJS/TEN. Comparatively, MDE displayed a cytotoxic T cell profile in skin without appreciable expansion and recruitment of cytotoxic CD8+ T cells from circulation, implicating TRMs as potential protagonists in skin-limited disease. Mechanistic interrogation in patients unable to recruit T cells from circulation into skin and in a parallel mouse model supported that skin TRMs were sufficient to mediate MDE. Concomitantly, SJS/TEN displayed a reduced Treg signature compared with MDE. DRESS demonstrated recruitment of cytotoxic CD8+ T cells into skin as in SJS/TEN, yet a pro-Treg signature as in MDE. These findings have important implications for fundamental skin immunology and clinical care.
Subject(s)
Hypersensitivity, Delayed , Skin , Humans , Animals , Mice , Skin/immunology , Skin/pathology , Female , Hypersensitivity, Delayed/immunology , Hypersensitivity, Delayed/genetics , Male , Stevens-Johnson Syndrome/immunology , Stevens-Johnson Syndrome/genetics , Stevens-Johnson Syndrome/pathology , Memory T Cells/immunology , Middle Aged , Adult , CD8-Positive T-Lymphocytes/immunology , Drug Eruptions/immunology , Drug Eruptions/pathology , Drug Eruptions/genetics , T-Lymphocytes, Cytotoxic/immunologyABSTRACT
Subacute cutaneous lupus erythematosus and chronic cutaneous lupus erythematosus are represented in the majority of cutaneous lupus subtypes, each of which has variable implications for systemic manifestations such as lupus nephritis. On dermatologic examination, subacute cutaneous lupus erythematosus and chronic cutaneous lupus erythematosus are distinct. However, it is often difficult to diagnose the subtype from histology alone. Our study utilized whole-genome microarray expression analysis on human skin samples of subacute cutaneous lupus erythematosus, on human skin samples of chronic cutaneous lupus erythematosus, and on healthy controls, along with analysis on human samples of lupus nephritis and normal kidney tissue to compare cutaneous lupus subtypes with each other as well as with lupus nephritis. The data revealed that cutaneous lupus subtypes were distinct from healthy control skin, with gene expression predominantly characterized by upregulation of IFN-1 and T-cell chemotactic genes. However, the cutaneous lupus subtypes were very similar to one another; comparative analyses revealed few statistically significant differences in gene expression. There were also distinct differences between the gene signatures of cutaneous lupus and lupus nephritis. Cutaneous lupus samples revealed gene signatures demonstrating a prominent inflammatory component that may suggest the skin as an early site of initiation of lupus pathogenesis, whereas lupus nephritis reflected the recruitment and activation of M2 macrophages and a wound healing signature.
Subject(s)
Gene Expression Profiling , Lupus Erythematosus, Cutaneous/metabolism , Lupus Erythematosus, Discoid/metabolism , Lupus Nephritis/metabolism , Skin/metabolism , Chemokines/genetics , Gene Ontology , Humans , Lupus Erythematosus, Cutaneous/pathology , Lupus Erythematosus, Discoid/pathology , Lupus Nephritis/pathologyABSTRACT
Toll-like receptors TLR7 and TLR9 are both implicated in the activation of autoreactive B cells and other cell types associated with systemic lupus erythematosus (SLE) pathogenesis. However, Tlr9-/- autoimmune-prone strains paradoxically develop more severe disease. We have now leveraged the negative regulatory role of TLR9 to develop an inducible rapid-onset murine model of systemic autoimmunity that depends on T cell detection of a membrane-bound OVA fusion protein expressed by MHC class II+ cells, expression of TLR7, expression of the type I IFN receptor, and loss of expression of TLR9. These mice are distinguished by a high frequency of OVA-specific Tbet+, IFN-γ+, and FasL-expressing Th1 cells as well as autoantibody-producing B cells. Unexpectedly, contrary to what occurs in most models of SLE, they also developed skin lesions that are very similar to those of human cutaneous lupus erythematosus (CLE) as far as clinical appearance, histological changes, and gene expression. FasL was a key effector mechanism in the skin, as the transfer of FasL-deficient DO11gld T cells completely failed to elicit overt skin lesions. FasL was also upregulated in human CLE biopsies. Overall, our model provides a relevant system for exploring the pathophysiology of CLE as well as the negative regulatory role of TLR9.
Subject(s)
Fas Ligand Protein/metabolism , Lupus Erythematosus, Cutaneous/immunology , Membrane Glycoproteins/metabolism , Toll-Like Receptor 7/metabolism , Toll-Like Receptor 9/deficiency , Animals , Autoantibodies/biosynthesis , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Disease Models, Animal , Female , Humans , Interferon Type I/metabolism , Lupus Erythematosus, Cutaneous/metabolism , Lupus Erythematosus, Cutaneous/pathology , Lymphocyte Activation , Male , Mice , Mice, Inbred BALB C , Mice, Knockout , Ovalbumin/immunology , Skin/immunology , Skin/pathology , Th1 Cells/immunology , Th1 Cells/metabolism , Toll-Like Receptor 9/genetics , Toll-Like Receptor 9/metabolismSubject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Simvastatin/administration & dosage , Vitiligo/drug therapy , Administration, Oral , Adolescent , Adult , Body Surface Area , Chemokine CXCL10/blood , Double-Blind Method , Humans , Male , Middle Aged , Severity of Illness Index , Treatment Outcome , Vitiligo/blood , Young AdultABSTRACT
Autosomal Dominant Polycystic Kidney Disease (ADPKD) remains a major health care concern affecting several million patients worldwide and for which there is no specific treatment. We have employed a 3D tissue engineered disease-like system to emulate cystic structures in vitro and analyzed the extracellular matrix (ECM) interactions in it. The tissue system was developed by culturing normal or polycystin-1 silenced mouse Inner Medullary Collecting Duct (mIMCD) cells in ECM infused into 3D porous silk protein biomaterial scaffolds. In this system, the silk scaffolds provide slow degradation, biocompatibility, and maintain structure and transport for the 3D system, while the ECM molecules retain biological signaling. Using this 3D tissue system we provide evidence for an autocrine signaling loop involving abnormal matrix deposition (collagen type IV and laminin) and its integrin receptor subunit protein (Integrin-ß1) in Pkd1 silenced mIMCD cells. In addition, we report that abnormal pericystic ECM interactions between matrix molecules and integrin subunit proteins regulate the rate of cystogenesis in the disease system. Molecular signaling showed abnormalities in cyclin proteins and cell-cycle progression upon Pkd1 knockdown. Importantly, disruption of the abnormal matrix interactions by an additional knockdown (double-silencing) of integrin-ß1 in Pkd1 silenced cells reversed the abnormalities and reduced the rate of cystogenesis. Together, these findings indicate that abnormal matrix deposition and altered integrin profile distribution as observed in ADPKD and are critical in cystogenesis and should be considered a target for the development of therapeutics.