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Gharaee-Kermani, M.

Publications and source records attributed to Gharaee-Kermani, M..

4 recordsLinked to original sources

Cross-disease comparison of dermatomyositis and lupus skin identifies inflammatory monocytes and JAK-1 signaling as drivers of vasculopathy in dermatomyositis

Dermatomyositis (DM) is a rare yet devastating autoimmune disease characterized by inflammatory and vasculopathic changes in skin and muscle. DM and systemic lupus erythematosus (lupus) skin lesions have overlapping clinical and histopathological features, yet disparate responses to available therapeutics. DM skin disease is often relapsing and recalcitrant. To investigate DM immunopathogenesis, non-lesional skin, lesional skin, and circulating immune cells from DM patients were analyzed using single-cell RNA-sequencing. Samples were analyzed in parallel with lesional and non-lesional lupus skin, healthy control skin, and peripheral blood. We demonstrate a pervasive type I interferon (IFN) signature in DM stroma that persists in culture and is distinguished from lupus by upregulation of VEGF and IL-18 signaling in DM keratinocytes. Furthermore, endothelial cells (ECs) in lesional DM exhibit decreased proliferation that was not observed in lupus. Using cell communication networks, we identified a population of DM-specific monocytes interacting with non-proliferating DM ECs. Co-culture of monocytes from DM patients with ECs resulted in increased EC apoptosis inhibited by JAK1 blockade. JAK1 inhibition also resulted in reversal of DM-stromal and inflammatory signatures. Together, our data provide a comprehensive cross-disease characterization of lesional and non-lesional skin of DM compared to lupus and implicate monocyte-mediated EC dysfunction in DM vasculopathy and support JAK inhibition for refractory skin disease.

immunology↗

Epidermal ZBP1 stabilizes mitochondrial Z-DNA to drive UV-induced IFN signaling in autoimmune photosensitivity

Photosensitivity is observed in numerous autoimmune diseases and drives poor quality of life and disease flares. Elevated epidermal type I interferon (IFN) production primes for photosensitivity and enhanced inflammation, but the substrates that sustain and amplify this cycle remain undefined. Here, we show that IFN-induced Z-DNA binding protein 1 (ZBP1) stabilizes ultraviolet (UV)B-induced cytosolic Z-DNA derived from oxidized mitochondrial DNA. ZBP1 is significantly upregulated in the epidermis of adult and pediatric patients with autoimmune photosensitivity. Strikingly, lupus keratinocytes accumulate extensive cytosolic Z-DNA after UVB, and transfection of keratinocytes with Z-DNA results in stronger IFN production through cGAS-STING activation compared to B-DNA. ZBP1 knockdown abrogates UV-induced IFN responses, whereas overexpression results in a lupus-like phenotype with spontaneous Z-DNA accumulation and IFN production. Our results highlight Z-DNA and ZBP1 as critical mediators for UVB-induced inflammation and uncover how type I IFNs prime for cutaneous inflammation in photosensitivity. One Sentence Summary: ZBP1 and mitochondrial Z-DNA drive autoimmune photosensitivity via cGAS-STING activation.

immunology↗

Integrated omics analysis unveils a DNA damage response to neurogenic injury

Spinal cord injury (SCI) evokes profound bladder dysfunction. Current treatments are limited by a lack of molecular data to inform novel therapeutic avenues. Previously, we showed systemic inosine treatment improved bladder function following SCI in rats. Here, we applied multi-omics analysis to explore molecular alterations in the bladder and their sensitivity to inosine following SCI. Canonical pathways regulated by SCI included those associated with protein synthesis, neuroplasticity, wound healing, and neurotransmitter degradation. Upstream regulator analysis identified MYC as a key regulator, whereas causal network analysis predicted multiple regulators of DNA damage response signaling following injury, including PARP-1. Staining for both DNA damage ({gamma}H2AX) and PARP activity (poly-ADP-ribose) markers in the bladder was increased following SCI, and attenuated in inosine-treated tissues. Proteomics analysis suggested that SCI induced changes in protein synthesis-, neuroplasticity-, and oxidative stress-associated pathways, a subset of which were shown in transcriptomics data to be inosine-sensitive. These findings provide novel insights into the molecular landscape of the bladder following SCI, and highlight a potential role for PARP inhibition to treat neurogenic bladder dysfunction. Synopsis O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/571015v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@7c3e79org.highwire.dtl.DTLVardef@e998f5org.highwire.dtl.DTLVardef@38fd4aorg.highwire.dtl.DTLVardef@17d3aba_HPS_FORMAT_FIGEXP M_FIG C_FIG O_LIEmployed a multi-omics approach, integrating both transcriptomic and proteomic analyses, to investigate the molecular response in a rat model of spinal cord injury (SCI) and the therapeutic effect of inosine. C_LIO_LIDiscovered multiple regulators of the DNA damage response, including PARP-1, using causal network analysis. C_LIO_LIObserved decreased markers of DNA damage and PARP activity in inosine-treated tissues, indicating the therapeutic potential of inosine in neurogenic dysfunction. C_LIO_LIIdentified significant alterations in molecular pathways associated with protein synthesis, neuroplasticity, wound healing, and neurotransmitter degradation after SCI, and their modulation by inosine, highlighting its neuroprotective effects beyond DNA damage repair. C_LI

cell biology↗

Non-lesional and Lesional Lupus Skin Share Inflammatory Phenotypes that Drive Activation of CD16+ Dendritic Cells

Cutaneous lupus erythematosus (CLE) is a disfiguring and poorly understood condition frequently associated with systemic lupus. Studies to date suggest that non-lesional keratinocytes play a role in disease predisposition, but this has not been investigated in a comprehensive manner or in the context of other cell populations. To investigate CLE immunopathogenesis, normal-appearing skin, lesional skin, and circulating immune cells from lupus patients were analyzed via integrated single-cell RNA-sequencing and spatial-seq. We demonstrate that normal-appearing skin of lupus patients represents a type I interferon-rich, prelesional environment that skews gene transcription in all major skin cell types and dramatically distorts cell-cell communication. Further, we show that lupus-enriched CD16+ dendritic cells undergo robust interferon education in the skin, thereby gaining pro-inflammatory phenotypes. Together, our data provide a comprehensive characterization of lesional and non-lesional skin in lupus and identify a role for skin education of CD16+ dendritic cells in CLE pathogenesis.

immunology↗