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Michelle Petri

Publications and source records attributed to Michelle Petri.

4 recordsLinked to original sources
PubMed2026

A highly prevalent lupus risk haplotype increases IRF7-dependent induction of IFN-α, enhancing antiviral defense and exacerbating autoimmunity.

Genome-wide association studies have identified genetic polymorphisms at 11p15 associated with systemic lupus erythematosus (lupus). Statistical fine mapping prioritizes a highly prevalent coding haplotype within IRF7. Analysis of ancient DNA confirms that this haplotype has persisted at high frequencies in the global population for millennia. The IRF7 risk haplotype is sufficient to increase nuclear localization of IRF7 and transcriptional activity downstream of pattern recognition receptor pathways. This risk haplotype increases IRF7 DNA-binding strength and alters IRF7 DNA sequence specificity, resulting in genotype-dependent increases in interferon-α production in numerous biological systems, including monocytes and airway epithelial cells. CRISPR engineering of the corresponding risk variant in mouse Irf7 results in both enhanced innate control of virus infection and increased autoantibody titers in a model of autoimmunity. Altogether, we establish a persistent and prominent IRF7 haplotype that amplifies IRF7 activity in a manner that has immunological risks and benefits.

ancient DNA↗
PubMed2026

Anifrolumab Treatment Leads to Rapid Reduction in Urinary Biomarkers of Intrarenal Inflammation in Lupus Nephritis: Results From the Phase 2 Randomized Trial.

OBJECTIVE: Lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE) and is partially driven by type I interferon signaling. Anifrolumab, an approved treatment for patients with SLE, has been investigated in a phase 2 trial in patients with LN receiving standard therapy (TULIP-LN, ClinicalTrials.gov identifier NCT02547922). We studied the impact of anifrolumab treatment on urinary biomarker expression in patients with LN through proteomic analysis of samples from TULIP-LN. METHODS: Urine samples were collected at weeks 0, 12, and 48 from patients treated with the anifrolumab basic regimen (n = 35), intensified regimen (n = 42), or placebo (n = 35), in addition to standard therapy, and analyzed for the presence of 197 proteins. The impact of anifrolumab relative to placebo on prespecified biomarkers linked to histologic activity was assessed, and a comparison of responders versus nonresponders was conducted on proteins detected in ≥75% of samples. RESULTS: Anifrolumab treatment significantly reduced urinary CD163 and monocyte chemoattractant protein 1 expression at week 12 versus placebo, including in patients classified as proteinuric nonresponders across all regimens. By week 48, biomarker levels declined in all groups, indicating that standard therapy alone can eventually suppress intrarenal inflammation but with slower kinetics. Proteomic analyses further revealed that anifrolumab was superior to placebo in reducing the proteomic inflammatory signature, regardless of responder status. CONCLUSION: Compared with placebo, anifrolumab treatment significantly reduced urinary biomarkers of renal histologic activity in patients with LN, which may accelerate the resolution of intrarenal inflammation, potentially preventing damage accrual.

Humans↗
PubMed2026

A highly prevalent lupus risk haplotype increases IRF7-dependent induction of IFN-α, enhancing antiviral defense and exacerbating autoimmunity.

UNLABELLED: Genome-wide association studies have identified genetic polymorphisms at 11p15 associated with Systemic Lupus Erythematosus (lupus). Statistical fine mapping prioritizes a highly prevalent coding haplotype within the IRF7 gene. Analysis of ancient DNA confirms that this haplotype has persisted at high frequencies in the global population for millennia. The IRF7 risk haplotype is sufficient to increase nuclear localization of IRF7 and transcriptional activity downstream of pattern recognition receptor pathways. This risk haplotype increases IRF7 DNA binding strength and alters IRF7 DNA sequence specificity, resulting in genotype-dependent increases in IFN-α production in numerous biological systems, including monocytes and airway epithelial cells. CRISPR engineering of a homologous risk variant in mouse Irf7 results in both enhanced innate control of virus infection and increased autoantibody titers in a model of autoimmunity. Altogether, we establish a persistent and prominent genetic IRF7 haplotype that amplifies IRF7 activity in a manner that has immunological risks and benefits. HIGHLIGHTS: Genetic analysis using modern and evolutionary datasets identifies a persistent and highly prevalent lupus-associated coding haplotype in IRF7 at 11p15 The IRF7 lupus risk haplotype increases IFN-α production by monocytes and airway epithelial cells The IRF7 lupus risk haplotype increases IRF7 DNA binding strength and alters DNA sequence specificity A homologous lupus risk variant in mouse Irf7 enhances control of vesicular stomatitis virus and exacerbates autoantibody production.

Journal Article↗
PubMed2025

A proteomic map of thromboinflammatory signatures in antiphospholipid syndrome: results from antiphospholipid syndrome alliance for clinical trials and international networking (APS ACTION) registry.

INTRODUCTION: Antiphospholipid syndrome (APS) is an autoimmune disease with thromboembolic and obstetric morbidity arising via a model of immunothrombosis. Individuals with APS may present with thrombotic (TAPS), obstetric (OAPS), or microvascular (MAPS) disease, while many have circulating antiphospholipid antibodies (aPL) without APS classification (NoAPS). Multiple pathophysiologic mechanisms have been proposed in APS, including activation by aPL of platelets, endothelial and immune cells, as well as complement and coagulation pathways; however, the pathophysiology of APS, particularly transition of clinical APS from aPL remains unclear. METHODS: Seeking to define the inflammatory signature of APS, we carried out an unbiased proteomic screen of persistently aPL-positive patients with different clinical phenotypes from the international APS Alliance for Clinical Trials and International Networking (ACTION) Registry and compared them to 10 healthy controls. 6398 unique proteins were estimated using an DNA aptamer-based assay. Subsequently, we validated our findings in 34 additional patients. RESULTS: Our data show that the mere presence of aPL confers a distinct thromboinflammatory signature characterized by the activation of coagulation, complement, innate and adaptive immune response pathways shared by all APS subtypes. Pathway enrichment analysis revealed increasing enrichment with rising statistical significance of thrombosis, complement, neutrophil and other innate and adaptive immune activation, as well as extracellular matrix (ECM) organization with increasing clinical severity, suggesting a model of progressive thromboinflammation in evolution of APS from NoAPS to TAPS and MAPS. CONCLUSIONS: Our findings provide novel insights into the pathogenesis of APS and identify potential novel targets for diagnostic and therapeutic intervention in APS across its entire spectrum.

Humans↗