scholarly journals Oxidized mitochondrial nucleoids released by neutrophils drive type I interferon production in human lupus

2016 ◽  
Vol 213 (5) ◽  
pp. 697-713 ◽  
Author(s):  
Simone Caielli ◽  
Shruti Athale ◽  
Bojana Domic ◽  
Elise Murat ◽  
Manjari Chandra ◽  
...  
Keyword(s):  
Lupus Erythematosus ◽  
Type I Interferon ◽  
High Mobility ◽  
Human Neutrophils ◽  
Type I ◽  
Healthy Human ◽  
Mitochondrial Nucleoids ◽  
Blood Neutrophils ◽  
Mitochondrial Origin

Autoantibodies against nucleic acids and excessive type I interferon (IFN) are hallmarks of human systemic lupus erythematosus (SLE). We previously reported that SLE neutrophils exposed to TLR7 agonist autoantibodies release interferogenic DNA, which we now demonstrate to be of mitochondrial origin. We further show that healthy human neutrophils do not complete mitophagy upon induction of mitochondrial damage. Rather, they extrude mitochondrial components, including DNA (mtDNA), devoid of oxidized (Ox) residues. When mtDNA undergoes oxidation, it is directly routed to lysosomes for degradation. This rerouting requires dissociation from the transcription factor A mitochondria (TFAM), a dual high-mobility group (HMG) protein involved in maintenance and compaction of the mitochondrial genome into nucleoids. Exposure of SLE neutrophils, or healthy IFN-primed neutrophils, to antiribonucleotide protein autoantibodies blocks TFAM phosphorylation, a necessary step for nucleoid dissociation. Consequently, Ox nucleoids accumulate within mitochondria and are eventually extruded as potent interferogenic complexes. In support of the in vivo relevance of this phenomenon, mitochondrial retention of Ox nucleoids is a feature of SLE blood neutrophils, and autoantibodies against Ox mtDNA are present in a fraction of patients. This pathway represents a novel therapeutic target in human SLE.

scholarly journals Targeted Delivery of Chloroquine to Plasmacytoid Dendritic Cells Enhances Inhibition of the Type I Interferon Response

2021 ◽  
Author(s):  
Marilyn E Allen ◽  
Amit Golding ◽  
Violeta Rus ◽  
Nicholas B Karabin ◽  
Sophia Li ◽  
...  
Keyword(s):  
Lupus Erythematosus ◽  
Targeted Delivery ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Interferon Response ◽  
Type I ◽  
Healthy Human ◽  
Biodistribution Studies

Systemic lupus erythematosus (SLE) causes damaging inflammation in multiple organs via the accumulation of immune complexes. These complexes activate plasmacytoid DCs (pDCs) via TLR7 and TLR9, contributing to disease pathogenesis by driving secretion of inflammatory type I IFNs. Antimalarial drugs, such as chloroquine (CQ), are TLR antagonists used to alleviate inflammation in SLE. However, they require ~3 months of continuous use before achieving therapeutic efficacy and can accumulate in the retinal pigment epithelium with chronic use resulting in retinopathy. We hypothesized that poly(ethylene glycol)-b-poly(propylene sulfide) (PEG-b-PPS) filamentous nanocarriers, filomicelles (FMs) could improve drug activity and reduce toxicity by directly delivering CQ to pDCs via passive, morphology-based targeting. Healthy human PBMCs were treated with soluble CQ or CQ-loaded FMs, stimulated with TLR agonists or SLE patient sera, and type I IFN secretion was quantified via multi-subtype IFN-α ELISA and MX1 gene expression using real-time RT-qPCR. Our results showed that 50 µg CQ/mg FM decreased MX1 expression and IFN-α production after TLR activation with either synthetic nucleic acid agonists or immune complex rich sera from SLE patients. Cellular uptake and biodistribution studies showed that FMs preferentially accumulate in human pDCs in vitro and in tissues frequently damaged in SLE patients (i.e., liver and kidneys) while sparing the eye in vivo. These results showed that nanocarrier morphology enables drug delivery, and CQ-FMs may be equally effective and more targeted than soluble CQ at inhibiting SLE-relevant pathways.

scholarly journals E3 ligase Nedd4l promotes antiviral innate immunity by catalyzing K29-linked cysteine ubiquitination of TRAF3

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Peng Gao ◽  
Xianwei Ma ◽  
Ming Yuan ◽  
Yulan Yi ◽  
Guoke Liu ◽  
...  
Keyword(s):  
Posttranslational Modifications ◽  
Type I Interferon ◽  
Zinc Fingers ◽  
E3 Ligase ◽  
Type I ◽  
E3 Ligases ◽  
Protein Posttranslational Modifications ◽  
Antiviral Innate Immunity

AbstractUbiquitination is one of the most prevalent protein posttranslational modifications. Here, we show that E3 ligase Nedd4l positively regulates antiviral immunity by catalyzing K29-linked cysteine ubiquitination of TRAF3. Deficiency of Nedd4l significantly impairs type I interferon and proinflammatory cytokine production induced by virus infection both in vitro and in vivo. Nedd4l deficiency inhibits virus-induced ubiquitination of TRAF3, the binding between TRAF3 and TBK1, and subsequent phosphorylation of TBK1 and IRF3. Nedd4l directly interacts with TRAF3 and catalyzes K29-linked ubiquitination of Cys56 and Cys124, two cysteines that constitute zinc fingers, resulting in enhanced association between TRAF3 and E3 ligases, cIAP1/2 and HECTD3, and also increased K48/K63-linked ubiquitination of TRAF3. Mutation of Cys56 and Cys124 diminishes Nedd4l-catalyzed K29-linked ubiquitination, but enhances association between TRAF3 and the E3 ligases, supporting Nedd4l promotes type I interferon production in response to virus by catalyzing ubiquitination of the cysteines in TRAF3.

Modulation of cardiometabolic disease markers by type I interferon inhibition in systemic lupus erythematosus

2020 ◽  
Author(s):  
Kerry A Casey ◽  
Michael A Smith ◽  
Dominic Sinibaldi ◽  
Nickie L Seto ◽  
Martin P Playford ◽  
...  
Keyword(s):  
Systemic Lupus Erythematosus ◽  
Lupus Erythematosus ◽  
Type I Interferon ◽  
Cardiometabolic Disease ◽  
Type I ◽  
Systemic Lupus ◽  
Disease Markers

scholarly journals A Potent In Vivo Antitumor Efficacy of Novel Recombinant Type I Interferon

2016 ◽  
Vol 23 (8) ◽  
pp. 2038-2049 ◽  
Author(s):  
Kang-Jian Zhang ◽  
Xiao-Fei Yin ◽  
Yuan-Qin Yang ◽  
Hui-Ling Li ◽  
Yan-Ni Xu ◽  
...  
Keyword(s):  
Type I Interferon ◽  
Antitumor Efficacy ◽  
Type I ◽  
Recombinant Type

scholarly journals Association between anti-interferon-alpha autoantibodies and COVID-19 in systemic lupus erythematosus

2020 ◽  
Author(s):  
Sarthak Gupta ◽  
Shuichiro Nakabo ◽  
Jun Chu ◽  
Sarfaraz Hasni ◽  
Mariana J. Kaplan
Keyword(s):  
Systemic Lupus Erythematosus ◽  
General Population ◽  
Lupus Erythematosus ◽  
Preventive Measures ◽  
Type I Interferon ◽  
Type I ◽  
List Type ◽  
Signal Transducer ◽  
Systemic Lupus

AbstractObjectivesAnti-type I interferon (IFN) autoantibodies have been reported in patients with systemic lupus erythematosus (SLE). Recently, an association of these autoantibodies with severe COVID-19 was reported in the general population. We assessed whether having pre-existing anti-IFNα autoantibodies was associated with COVID-19 infection in SLE patients.MethodsPatients with SLE who developed COVID-19 between April 1st to October 1st, 2020 were studied. Biobanked pre-COVID-19 plasma from these SLE subjects and healthy controls were tested for anti-IFNα IgG autoantibodies by ELISA. The ability of plasma anti-IFNα autoantibodies to block signal transducer and activator of transcription 1 (STAT1) phosphorylation by recombinant human IFNα in vitro was assessed by flow cytometry.ResultsTen SLE subjects with COVID-19 were identified. A 40% of these subjects had stable autoantibodies against IFNα for up to three years preceding COVID-19 diagnosis. A 50% of the subjects with these autoantibodies neutralized IFNα induced STAT1 phosphorylation.None of the other SLE samples blocked IFNα signaling.ConclusionsWe noted an increased prevalence of pre-existing anti-IFNα autoantibodies in SLE patients with COVID-19 compared to the reported prevalence in lupus patients and the general population with severe COVID-19. Autoantibodies against IFNα in SLE patients may be pathogenic and patients with them maybe at-risk of developing COVID-19.Key MessagesWhat is already known about this subject?-Anti-type I interferon (IFN) autoantibodies have been reported in patients with systemic lupus erythematosus (SLE) and have recently been associated with severe COVID-19 in the general population.What does this study add?-SLE subjects with COVID-19 had an increased prevalence of pre-existing anti-IFNα autoantibodies compared to the reported prevalence in lupus patients and the general population with severe COVID-19.-Plasma from 50% of subjects with these autoantibodies were able to block in vitro activity of IFNα.-SLE patients with pre-existing anti-IFNα autoantibodies had more severe COVID-19 manifestations.How might this impact on clinical practice or future developments?-Anti-IFNα autoantibodies may be pathogenic and could prove to be a helpful prognostic marker to predict which SLE patient may develop COVID-19 and inform preventive measures and management of this subset of patients.

scholarly journals Identification and characterization of a unique subpopulation (CALLA/CD10/negative) of human neutrophils manifesting a heightened chemotactic response to activated complement

Blood ◽  
1987 ◽  
Vol 70 (5) ◽  
pp. 1624-1629
Author(s):  
RT McCormack ◽  
RD Nelson ◽  
DE Chenoweth ◽  
TW LeBien
Keyword(s):  
Lymphoblastic Leukemia ◽  
Low Frequency ◽  
Chemotactic Response ◽  
Human Neutrophils ◽  
Normal Peripheral Blood ◽  
Cd10 Expression ◽  
Blood Neutrophils

We have previously demonstrated that human neutrophils synthesize the common acute lymphoblastic leukemia antigen (CALLA/CD10). To determine whether CALLA/CD10-positive and -negative neutrophils have similar or distinct functional attributes, we sorted normal peripheral blood neutrophils for CALLA/CD10 expression and compared their chemotactic ability. Surprisingly, the low-frequency (approximately 5%), CALLA/CD10- negative neutrophils displayed a dramatically heightened chemotactic response to activated complement (C') that was (a) specific for C', (b) not observed with other minor subpopulations of neutrophils, (c) not due to previous activation in vivo or in vitro, and (d) apparently not due to an increase in C5a receptors. These results underscore the concept of neutrophil heterogeneity and prompt the hypothesis that CALLA/CD10-negative neutrophils may participate in an inflammatory response to trauma involving complement activation.

scholarly journals Type I interferon responses to ischemic injury begin in the bone marrow of mice and humans and depend on Tet2, Nrf2, and Irf3

2019 ◽  
Author(s):  
David M. Calcagno ◽  
Richard P. Ng ◽  
Avinash Toomu ◽  
Claire Zhang ◽  
Kenneth Huang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Type I Interferon ◽  
Tissue Injury ◽  
Type I ◽  
Blood Neutrophils ◽  
Clinical Biomarker ◽  
Acute Mi ◽  
Molecular Patterns ◽  
Interferon Responses ◽  
Myeloid Progenitors

AbstractSterile tissue injury locally activates innate immune responses via interactions with damage associated molecular patterns (DAMPs). Here, by analyzing ∼120K single cell transcriptomes after myocardial infarction (MI) in mice and humans, we show neutrophil and monocyte subsets induce type I interferon (IFN) stimulated genes (ISGs) in myeloid progenitors of the bone marrow, far from the site of injury. In patients with acute MI, peripheral blood neutrophils and monocytes express ISGs at levels far beyond healthy individuals and comparable to patients with lupus. In the bone marrow of Tet2-/- mice, ISGs are spontaneously induced in myeloid progenitors and their progeny. In the heart, IFN responses are negatively regulated by Ccr2- resident macrophages in a Nrf2-dependent fashion. Our results show post-MI IFN signaling begins in the bone marrow, implicate multiple transcription factors in its regulation (Tet2, Irf3, Nrf2), and provide a clinical biomarker (ISG score) for studying post-MI IFN signaling in patients.

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