Plasmacytoid Dendritic Cells Are Not Major Producers of Type 1 IFN in Cutaneous Lupus: An In-Depth Immunoprofile of Subacute and Discoid Lupus.

The immunologic drivers of cutaneous lupus erythematosus (CLE) and its clinical subtypes remain poorly understood. We sought to characterize the immune landscape of discoid lupus erythematosus and subacute CLE using multiplexed immunophenotyping. We found no significant differences in immune cell percentages between discoid lupus erythematosus and subacute CLE (P > .05) with the exception of an increase in TBK1 in discoid lupus erythematosus (P < .05). Unbiased clustering grouped subjects into 2 major clusters without respect to clinical subtype. Subjects with a history of smoking had increased percentages of neutrophils, disease activity, and endothelial granzyme B compared with nonsmokers. Despite previous assumptions, plasmacytoid dendritic cells (pDCs) did not stain for IFN-1. Skin-eluted and circulating pDCs from subjects with CLE expressed significantly less IFNα than healthy control pDCs upon toll-like receptor 7 stimulation ex vivo (P < .0001). These data suggest that discoid lupus erythematosus and subacute CLE have similar immune microenvironments in a multiplexed investigation. Our aggregated analysis of CLE revealed that smoking may modulate disease activity in CLE through neutrophils and endothelial granzyme B. Notably, our data suggest that pDCs are not the major producers of IFN-1 in CLE. Future in vitro studies to investigate the role of pDCs in CLE are needed.

Herbal supplement Spirulina stimulates inflammatory cytokine production in patients with dermatomyositis in vitro.

Spirulina, an herbal supplement and popular ingredient in health foods, is a potent stimulant of the immune system. Spirulina use is temporally associated with the onset or exacerbation of Dermatomyositis (DM), an autoimmune connective tissue disease that frequently affects the skin and muscle. In this study, we investigated the effect of Spirulina on peripheral blood mononuclear cells (PBMCs) in DM and Healthy Controls (HCs), showing that Spirulina stimulates Interferon ß (IFNß), Tumor necrosis factor α (TNFα), and Interferon γ (IFNγ) production of DM PBMCs primarily via Toll-Like Receptor 4 (TLR4) activation using ELISA (enzyme linked immunosorbent assay) and flow cytometry. We show that classical monocytes and monocyte-derived dendritic cells are stimulated by Spirulina and are activated via TLR4. Skin from patients with Spirulina-associated DM exhibits an inflammatory milieu similar to that of idiopathic DM but with a stronger correlation of TLR4 and IFNγ.

Multidimensional Immune Profiling of Cutaneous Lupus Erythematosus In Vivo Stratified by Patient Response to Antimalarials.

OBJECTIVE: The pathogenesis of cutaneous lupus erythematosus (CLE) is multifactorial, and CLE is difficult to treat due to the heterogeneity of inflammatory processes among patients. Antimalarials such as hydroxychloroquine (HCQ) and quinacrine (QC) have long been used as first-line systemic therapy; however, many patients do not respond to treatment with antimalarials and require systemic immunosuppressants that produce undesirable side effects. Given the complexity and the unpredictability of responses to antimalarial treatments in CLE patients, we sought to characterize the immunologic profile of patients with CLE stratified by subsequent treatment outcomes to identify potential biomarkers of inducible response. METHODS: We performed mass cytometry imaging of multiple immune cell types and inflammation markers in treatment-naive skin biopsy samples from 48 patients with CLE to identify baseline immunophenotypes that may predict the response to antimalarial therapy. Patients were stratified according to their response to treatment with antimalarials, as HCQ responders, QC responders, or nonresponders. RESULTS: HCQ responders demonstrated increased CD4+ T cells compared to the QC responder group. Patients in the nonresponder group were found to have decreased Treg cells compared to QC responders and increased central memory T cells compared to HCQ responders. QC responders expressed increased phosphorylated stimulator of interferon genes (pSTING) and interferon-κ (IFNκ) compared to HCQ responders. Phosphorylated STING and IFNκ were found to be localized to conventional dendritic cells (cDCs), and the intensity of pSTING and IFNκ staining was positively correlated with the number of cDCs on a tissue and cellular level. Neighborhood analysis revealed decreased regulatory cell interactions in nonresponder patients. Hierarchical clustering revealed that nonresponder patients could be further differentiated based on expression of pSTAT2, pSTAT3, pSTAT4, pSTAT5, phosphorylated interferon regulatory factor 3 (pIRF3), granzyme B, pJAK2, interleukin-4 (IL-4), IL-17, and IFNγ. CONCLUSION: These findings indicate differential immune cell compositions between patients with CLE, offering guidance for future research on precision-based medicine and treatment response.

Plasma-derived DNA containing-extracellular vesicles induce STING-mediated proinflammatory responses in dermatomyositis.

Objectives: Extracellular vesicles (EVs) are lipid bilayer membrane vesicles that are present in various bodily fluids and have been implicated in autoimmune disease pathogenesis. Type I interferons (IFN), specifically IFN-ß, are uniquely elevated in dermatomyositis (DM). The stimulator of interferon genes (STING) works as a critical nucleic acid sensor and adaptor in type I IFN signaling with possible implications in autoimmune diseases such as DM. In the current study, we investigated whether circulating EVs contribute to proinflammatory effects in DM, whether these proinflammatory responses are mediated by the STING signaling pathway, and if so, by what mechanism STING is activated. Methods: We collected and characterized EVs from plasma of healthy controls (HC) and DM patients; analyzed their abilities to trigger proinflammatory cytokines release by ELISA, and explored STING signaling pathway activation using immunoblot and immunofluorescent staining. STING signaling pathway inhibitors and RNAi were used to further investigate whether STING was involved in EVs-triggered proinflammatory response. DNase/lipid destabilizing agent was utilized to digest EVs and their captured DNA contents to evaluate how EVs triggered STING-mediated proinflammatory response in DM. Results: EVs isolated from DM plasma triggered proinflammatory cytokines including type I IFN release with STING signaling pathway activation. The activated STING pathway was preferentially mediated by dsDNA captured by EVs. Suppression of STING or its downstream signaling proteins attenuated the EVs-mediated proinflammatory response. Conclusions: Plasma-derived, DNA containing-EVs induced STING-mediated proinflammatory effects in DM. Targeting the STING pathway may be a potential therapeutic approach for DM.

Brain Homogenate Decoys for Antigen-Specific Cell Amplification.

Multiple sclerosis is complex and heterogeneous. Better tools are needed to be able to monitor this disease among individuals, but blood-based biomarkers are often too rare to profile. In this work, we developed antigen-specific biomaterials to replicate the central nervous system niche where multiple sclerosis biomarkers are amplified. We incorporated mouse brain homogenate into a microporous gelatin methacrylate network. Homogenate-containing biomaterials differentially stimulated cells and led to the marked amplification of disease-relevant, antigen-specific B cells. These results demonstrate that biomaterials containing primary tissue homogenate retain antigen specificity and may be a useful tool for decoding human autoimmunity.

Assessment and management of the heightened risk for atherosclerotic cardiovascular events in patients with lupus erythematosus or dermatomyositis.

For patients with lupus erythematosus (LE) or dermatomyositis (DM), there is an urgent need to address a heightened risk of clinical events, chiefly heart attacks and strokes, caused by atherosclerotic cardiovascular disease (ASCVD). Patients with LE or DM frequently exhibit high levels of conventional risk factors for ASCVD events, particularly dyslipoproteinemia and hypertension; an amplified burden of atherosclerotic plaques; and increased age- and sex-adjusted rates of ASCVD events compared with the general population. The rate of ASCVD events exceeds what would be expected from conventional risk factors, suggesting that disease-specific autoimmune processes exacerbate specific, known pathogenic steps in atherosclerosis. Importantly, despite their heightened risk, patients with LE or DM are often undertreated for known causative agents and exacerbators of ASCVD. Herein, we propose an approach to assess and manage the heightened risk of ASCVD events in patients with LE or DM. Our approach is modeled in large part on established approaches to patients with diabetes mellitus or stage 3 or 4 chronic kidney disease, which are well-studied conditions that also show heightened risk for ASCVD events and have been explicitly incorporated into standard clinical guidelines for ASCVD. Based on the available evidence, we conclude that patients with LE or DM require earlier and more aggressive screening and management of ASCVD. We suggest that physicians consider implementing multipliers of conventional risk calculators to trigger earlier initiation of lifestyle modifications and medical therapies in primary prevention of ASCVD events, employ vascular imaging to quantify the burden of subclinical plaques, and treat to lower lipid targets using statins and newer therapies, such as PCSK9 inhibitors, that decrease ASCVD events in nonautoimmune cohorts. More clinical vigilance is needed regarding surveillance, prevention, risk modification, and treatment of dyslipidemias, hypertension, and smoking in patients with LE or DM. All of these goals are achievable.

Comparative Study of Compounded Anesthetic Benzocaine/Lidocaine/Tetracaine (BLT) Cream with and without Abrasive Particles.

Objective: The purpose of this study was to compare the use of benzocaine, lidocaine, tetracaine (BLT) cream with and without abrasive particles to see which type of cream is more effective in reducing discomfort during cosmetic dermatologic procedures, specifically procedures using hyaluronic acid (HA) injectables. Methods: The study was conducted as a single-site, double-blind, paired study. Participants: Thirty-one subjects were enrolled. Men and women over 18, but not more than 75 years of age, were included. Participants were randomized to receive two types of BLT creams in a split-face fashion to two opposite anatomical face locations that require a similar amount of filler. Results: The study found a statistically significant difference (P<0.05) in the mean pain level as measured by the VAS and Wong-Baker Faces Pain Rating Scale when compared between baseline and the time when the procedure was started at the first needle stick. Subjects expressed significantly less pain with baseline and more pain when the procedure was done. However, the authors found that the mean pain level at first needle stick is lower with the abrasive type of BLT. Conclusion: The study demonstrated that subjects experienced a higher mean pain level (but not statistically significant) when using the BLT with smooth texture compared to the BLT with abrasive particles when applied before HA dermal filler injection.