ERAP1 and ERAP2 Gene Variants as Potential Clinical Biomarkers of Anti-IL-17A Response in Psoriasis Vulgaris.

BACKGROUND: Interleukin-17A (IL-17A) is a proinflammatory cytokine, playing an essential role in the development of psoriasis. Although treatment with anti-IL-17A monoclonal antibodies has demonstrated high efficacy in psoriasis patients, not all patients respond equally well, highlighting the need for biomarkers to predict treatment response. Specific single nucleotide polymorphisms (SNPs) in the endoplasmatic reticulum aminopeptidase (ERAP) 1 and 2 genes have been associated with psoriasis and other immune-mediated diseases. OBJECTIVES: We aimed to investigate the association between the ERAP1 and ERAP2 genotypes and response to secukinumab treatment in psoriasis patients. METHODS: A total of 75 patients with plaque psoriasis were included. All patients were genotyped for the ERAP1 rs27524, rs27044, rs30187, rs2287987, and rs26653 SNPs, the ERAP2 rs2248374 SNP, and human leukocyte antigen-C*06:02 (HLA-C*06:02) status. RESULTS: Our results demonstrated that individuals with specific ERAP1 and ERAP2 genotypes had a considerably lower response rate to secukinumab treatment. Patients with the ERAP2 rs2248374 G/G genotype had a more than 6-fold increased risk of treatment failure compared with patients with the rs2248374 A/G or -A/A genotypes. Stratifying for HLA-C*06:02 status, the ERAP2 G/G genotype pointed towards an increased risk of treatment failure among HLA-C*06:02-positive patients, although this was not statistically significant. CONCLUSION: Taken together, this unique study breaks new ground by identifying distinct ERAP1 and ERAP2 gene variants that may serve as potential biomarkers for predicting the treatment response to secukinumab in psoriasis patients. Notable, out data extends existing knowledge by linking specific ERAP1 and ERAP2 gene variants to treatment outcome.

A Novel CDC42 Variant with Impaired Thymopoiesis, IL-7R Signaling, PAK1 Binding, and TCR Repertoire Diversity.

Genetic variants in cell division cycle 42 (CDC42) can manifest with dysmorphic features, autoinflammation, hemophagocytic lymphohistiocytosis, and thrombocytopenia, whereas defective thymopoiesis is a rare disease manifestation. We report a novel CDC42 missense variant (c.46A > G, p.Lys16Glu) resulting in infection and HPV-driven carcinogenesis in the mosaic mother and impaired thymopoiesis and profound T cell lymphopenia in the heterozygous daughter identified through newborn screening for SCID. We found that surface expression of IL-7Rα (CD127) was decreased, consistent with reduced IL-7-induced STAT5 phosphorylation and accelerated apoptotic T cell death. Consistent with the vital role of IL-7 in regulating thymopoiesis, both patients displayed reduced T cell receptor CDR3 repertoires. Moreover, the CDC42 variant prevented binding to the downstream effector, p21-activated kinase (PAK)1, suggesting this impaired interaction to underlie reduced IL-7Rα expression and signaling. Here, we provide the first report of severely compromised thymopoiesis and perturbed IL-7Rα signaling caused by a novel CDC42 variant and presenting with diverging clinical and immunological phenotypes in patients.

Examination of autoantibodies to type I interferon in patients suffering from long COVID.

Long COVID (LC) is an emerging global health concern. The underlying mechanism and pathophysiology remain unclear. Presence of neutralizing autoantibodies against type 1 interferons (IFN) has been established as a predictor of critical COVID-19. We hypothesized that persistent autoimmune activity with autoantibodies against type 1 IFN may contribute to symptoms in patients with LC. Plasma samples and clinical information were obtained from a Danish LC cohort consisting of adult patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Information on symptoms and quality of life was derived from an LC-specific questionnaire and the EQ-5D-5L questionnaire. Detection of type 1 IFN autoantibodies in plasma were performed by ELISA. Samples collected between June, 2020, and September, 2021, from 279 patients were analyzed and compared to a control group of 94 individuals with prior mild SARS-CoV-2 infection who did not develop LC symptoms. In total, five LC patients (1.8%) and 3 (3.2%) of the controls had detectable circulating type 1 IFN autoantibodies. Collectively, prevalence of autoantibodies against type 1 IFN subtypes in our LC cohort were primarily driven by men and did not exceed the prevalence in controls. Thus, in our cohort, anti-type I IFN autoantibodies are unlikely to drive LC symptoms.

Long-term ear-EEG monitoring of sleep - A case study during shift work.

The interest in sleep as a potential clinical biomarker is growing, but the standard method of sleep assessment, polysomnography, is expensive, time consuming, and requires a lot of expert assistance for both set-up and interpretation. To make sleep analysis more available both in research and in the clinic, there is a need for a reliable wearable device for sleep staging. In this case study, we test ear-electroencephalography. A wearable, where electrodes are placed in the outer ear, as a platform for longitudinal at-home recording of sleep. We explore the usability of the ear-electroencephalography in a shift work case with alternating sleep conditions. We find the ear-electroencephalography platform to be reliable both in terms of showing substantial agreement to polysomnography after long-time use (with an overall agreement, using Cohen's kappa, of 0.72) and by being unobtrusive enough to wear during night shift conditions. We find that fractions of non-rapid eye movement sleep and transition probability between sleep stages show great potential as sleep metrics when exploring quantitative differences in sleep architecture between shifting sleep conditions. This study shows that the ear-electroencephalography platform holds great potential as a reliable wearable for quantifying sleep "in the wild", pushing this technology further towards clinical adaptation.

Trajectory for 66 patients treated with periacetabular osteotomy (PAO) and subsequent total hip arthroplasty: a follow-up study including 1378 hips from the Aarhus PAO database.

INTRODUCTION: Outcomes for patients treated with PAO and subsequent total hip arthroplasty (THA) remain unclear. We evaluated patient-reported outcomes among patients treated with PAO and subsequent THA and investigated differences in the number of additional surgical procedures after PAO among patients treated with PAO and subsequent THA and patients treated with PAO only. MATERIALS AND METHODS: 1378 hips underwent PAO and subsequently 66 hips were treated with THA. We evaluated the Hip disability and Osteoarthritis Outcome Score (HOOS) and physical activity questions for the 66 hips. Additional surgery after PAO was identified through inquiry to the Danish National Patient Registry. RESULTS: 13% undergoing PAO and subsequent THA reported a HOOS pain score ≤ 50 indicating a clinical failure. The risk difference for hip arthroscopy after PAO within 2 and 4 years was 14% (CI 5-23%) and 26% (CI 15-38%) in favor of hips treated with PAO only. Similarly, the risk difference for screw removal within 2 and 4 years was 19% (CI 8-29%) and 23% (CI 12-34%). CONCLUSION: 87% of patients undergoing PAO and subsequent THA had little or no hip pain. However, these patients received a high number of additional surgeries after PAO. Surgeons and patients may consider if additional surgery after PAO may be the first choice in a series of actions leading to conversion to THA.

Postpartum Disseminated Herpes Simplex Virus Type 1 Infection With Hemophagocytic Lymphohistiocytosis and Fulminant Neonatal Herpes Infection.

The present study describes a 19-year-old woman with systemic herpes simplex virus (HSV)-1 infection and hemophagocytic lymphohistiocytosis (HLH) postpartum, and a fatal course of neonatal herpesvirus infection. Functional investigation of cells from the mother demonstrated significantly impaired induction of antiviral interferons and cytokines in the context of normal activation of the transcription factors NF-κB and IRF3. Whole-exome sequencing did not reveal any functionally validated genetic variants. We suggest that the functionally impaired antiviral responses, potentially caused by a variant in CASP8 or other variants in noncoding regions of the genome, contributed to the unusually severe disease course observed in two generations.

A Distinct Dexamethasone-Dependent Gene Expression Profile in the Lungs of COVID-19 Patients.

The effects of dexamethasone (DXM) treatment on pulmonary immunity in COVID-19-associated acute respiratory distress syndrome (CARDS) remain insufficiently understood. We performed transcriptomic RNA-seq analysis of bronchoalveolar lavage fluid from 20 mechanically ventilated patients: 12 with CARDS (with or without DXM) and 8 non-COVID-19 critically ill controls. CARDS with DXM was characterized by upregulation of genes related to B-cell and complement pathway activation, antigen presentation, phagocytosis, and FC-γ receptor signaling. Most interferon-stimulated genes were upregulated in CARDS, particularly in CARDS without DXM. In conclusion, DXM treatment was not associated with regulation of proinflammatory pathways in CARDS but with regulation of other local immune responses. Clinical Trials Registration. NCT04354584.

STK4 Deficiency Impairs Innate Immunity and Interferon Production Through Negative Regulation of TBK1-IRF3 Signaling.

BACKGROUND: STK4 deficiency due to homozygous mutations in the STK4 gene encoding the STK4/MST1 kinase was first described in 2012. STK4/MST1 kinase regulates cell proliferation, survival, differentiation, and immune responses through canonical and non-canonical Hippo signaling pathways. OBJECTIVE: We describe an 11-year-old girl with a clinical presentation consisting of severe recurrent herpes zoster, chronic warts, and recurrent pneumonias, as well as a somatic phenotype with hypothyroidism and low stature. Whole exome sequencing revealed STK4 deficiency due to homozygosity for a novel frameshift variant in STK4, c.523dupA, p.(L174fsTer45), resulting in a premature stop codon within the kinase domain. METHODS: We performed a thorough investigation of the genetics and innate and adaptive immunological abnormalities in STK4 deficiency. RESULTS: We show significantly impaired type I, II, and III interferon (IFN) responses and partly reduced proinflammatory cytokine responses to ligands of Toll-like receptor (TLR)3, TLR9, and the cytosolic RNA and DNA sensors as well as to microorganisms. Impaired IFN responses could be attributed to reduced phosphorylation of TBK1 and IRF3. Moreover, virus infection induced enhanced cell death by apoptosis. Importantly, autophagy pathways were slightly disturbed, with enhanced LC3B-Ito LCB3-II conversion at the single cell level but normal overall formation of LCB3 punctae. Finally, the patient displayed some indicators of impaired adaptive immunity in the form of insufficient vaccination responses, T cell lymphopenia, and reduced Treg fractions, although with largely normal T cell proliferation and normal IFNg production. CONCLUSION: Here, we demonstrate disturbances in various immune cell populations and pathways involved in innate immune responses, cell death, autophagy, and adaptive immunity in a patient homozygous for a novel STK4 frameshift mutation.

Interferon signature in patients with STAT1 gain-of-function mutation is epigenetically determined.

STAT1 gain-of-function (GOF) variants lead to defective Th17 cell development and chronic mucocutaneous candidiasis (CMC), but frequently also to autoimmunity. Stimulation of cells with STAT1 inducing cytokines like interferons (IFN) result in hyperphosphorylation and delayed dephosphorylation of GOF STAT1. However, the mechanism how the delayed dephosphorylation exactly causes the increased expression of STAT1-dependent genes, and how the intracellular signal transduction from cytokine receptors is affected, remains unknown. In this study we show that the circulating levels of IFN-α were not persistently elevated in STAT1 GOF patients. Nevertheless, the expression of interferon signature genes was evident even in the patient with low or undetectable serum IFN-α levels. Chromatin immunoprecipitation (ChIP) experiments revealed that the active chromatin mark trimethylation of lysine 4 of histone 3 (H3K4me3), was significantly enriched in areas associated with interferon-stimulated genes in STAT1 GOF cells in comparison to cells from healthy donors. This suggests that the chromatin binding of GOF STAT1 variant promotes epigenetic changes compatible with higher gene expression and elevated reactivity to type I interferons, and possibly predisposes for interferon-related autoimmunity. The results also suggest that epigenetic rewiring may be responsible for treatment failure of Janus kinase 1/2 (JAK1/2) inhibitors in certain patients.

Autoinflammatory disease with corneal and mucosal dyskeratosis caused by a novel NLRP1 variant.

OBJECTIVES: Here we investigated a patient with inflammatory corneal intraepithelial dyskeratosis, mucosal inflammation, tooth abnormalities and, eczema to uncover the genetic and immunological basis of the disease. METHODS: On suspicion of an autoinflammatory condition, Sanger sequencing of nucleotide-binding oligomerization domain-like, leucine-rich repeat pyrin domain containing 1 (NLRP1) was performed and combined with an in vitro inflammasome reconstitution assay to measure caspase-1-mediated IL-1ß cleavage, stimulation of patient peripheral blood mononuclear cells (PBMCs) and whole blood to measure IL-1ß, IL-18 production and quantification of apoptosis-associated speck-like protein containing CARD (ASC) speck formation as a measure of inflammasome activation by flow cytometry. RESULTS: Sanger sequencing revealed a novel mutation (c.175G>C, p.A59P; NM_33004.4) in the inflammasome molecule NLRP1 segregating with disease, although with incomplete penetrance, in three generations. We found that patient PBMCs produced increased IL-1ß in response to inflammatory stimuli, as well as increased constitutive levels of IL-18. Moreover, we demonstrate that expression of the identified NLRP1 A59P variant caused spontaneous IL-1ß cleavage to mature IL-1ß. In addition, patient PBMCs responded to NLRP1 stimulation with increased ASC speck formation as a reflection of elevated inflammasome activity. CONCLUSION: We demonstrate that this novel NLRP1 A59P variant caused increased activation of the NLRP1 inflammasome, resulting in constitutively and inducibly elevated IL-1ß and IL-18 synthesis. We suggest the NLRP1 mutation underlies the pathogenesis of this rare autoinflammatory dyskeratotic disease inherited in an autosomal dominant manner with incomplete penetrance in the patient and within the family for several generations.

Systemic juvenile idiopathic arthritis and recurrent macrophage activation syndrome due to a CASP1 variant causing inflammasome hyperactivation.

OBJECTIVES: We investigated a patient with systemic juvenile idiopathic arthritis (sJIA) and recurrent macrophage activation syndrome (MAS) to discover genetic and immunological contributing factors. METHODS: Severe recurrent MAS motivated whole exome sequencing (WES) to identify genetic variants potentially involved in disease pathogenesis. In vitro peripheral blood mononuclear cell (PBMC) stimulations for cytokine expression and caspase-1 activity assays as well as NF-κB reporter luciferase assays were performed to functionally characterize variants. RESULTS: WES revealed an extremely rare heterozygous missense variant, c.482G>A, p.R161H in the CASP1 gene encoding pro-caspase-1. Lipopolysaccharide (LPS) stimulation of patient PBMCs induced high levels of IL-6 compared to controls, and activation of the NLRP3 inflammasome resulted in increased production of IL-1ß and IL-18 as well as significantly elevated caspase-1 activity. Constitutive and inducible levels of IL-18 and IFNγ in whole blood were markedly elevated. Expression of the CASP1 variant in an NF-κB reporter luciferase assay induced increased NF-κB activation in a RIP2-dependent manner. The disease course of the patient was complicated by severe recurrent MAS. However, dual IL-1 and IL-6 blockade caused disease remission. CONCLUSION: For the first time, we demonstrate the involvement of a CASP1 variant in sJIA and recurrent MAS. This variant is gain-of-function for both inflammasome and NF-κB activation leading to increased production of IL-6, IL-1ß and IL-18. Although dual IL-1 and IL-6 blockade may be beneficial in patients, in whom single treatment is not sufficient to control MAS, caution should be practiced, since interstitial lung disease may progress despite apparent clinical and biochemical remission.

Ear-EEG-based sleep scoring in epilepsy: A comparison with scalp-EEG.

Ear-EEG is a wearable electroencephalogram-recording device. It relies on recording electrodes that are nested within a custom-fitted earpiece in the external ear canal. The concept has previously been tested for seizure detection in epileptic patients and for sleep recordings in a healthy population. This study is the first to examine the use of ear-EEG recordings for sleep staging in patients with epilepsy, comparing it with standard recordings from scalp-EEG. We use individuals with epilepsy because of their multiple sleep disturbances, and their complex relationship between seizures and sleep, which make this group very likely to benefit from wearable electroencephalogram devices for sleep if it were introduced in the clinic. The accuracy of the ear-EEG against that of the scalp-EEG is compared for sleep staging, and we evaluate features of sleep architecture in individuals with epilepsy. A mean kappa value of 0.74 is found for the agreement between hypnograms derived from ear-EEG and scalp-EEG. Furthermore, it was discovered that sleep stage transition frequency could be contributing to the kappa variation. These findings are related to other ear-recording systems in the literature, and the potentials and future obstacles of the device are discussed.

Impaired immune responses to herpesviruses and microbial ligands in patients with MonoMAC.

MonoMAC is a complex primary immunodeficiency caused by mutations in the myeloid transcription factor GATA2, characterized by multilineage cytopenia with malignant complications and severe infections, including mycobacteria and herpesviruses. We describe the clinical presentation, genetics and antiviral inflammatory responses in a small case series. Two patients presented in childhood with mycobacterial infection and were diagnosed with MonoMAC germline GATA2 variants; their healthy fathers with the same mutations were also studied. Three patients were elderly individuals with acquired GATA2 mutations and malignant haematological conditions. Overall, this study demonstrates the heterogeneous clinical presentation and variation in immunodeficiency caused by GATA2 mutations.

Defective interferon priming and impaired antiviral responses in a patient with an IRF7 variant and severe influenza.

Influenza infection is common worldwide with many individuals affected each year during epidemics and occasionally pandemics. Previous studies in animal models and a few human cases have established an important role of innate type I and III interferon (IFN) for viral elimination and mounting of antiviral responses. However, genetic and immunological determinants of very severe disseminated influenza virus infection in humans remain incompletely understood. Here, we describe an adult patient with severe influenza virus A (IAV) infection, in whom we identified a rare variant E331V in IFN regulatory factor (IRF)7 by whole-exome sequencing. Examination of patient cells demonstrated a cellular phenotype suggesting functional IRF7 impairment, since priming with IFN was almost abolished and IFN responses to IAV were significantly impaired in patient cells. Moreover, IAV replication was significantly higher in patient cells than in controls. Finally, expression of IRF7 E331V in HEK293 cells demonstrated significantly reduced activation of both IFNA7 and IFNB promoters in a luciferase reporter gene expression assay compared to IRF7 wild type. These findings provide further support for the essential role of IRF7 in amplifying antiviral IFN responses to ensure potent and sustained IFN responses during influenza virus infection in humans.

Listeria monocytogenes induces IFNß expression through an IFI16-, cGAS- and STING-dependent pathway.

Listeria monocytogenes is a gram-positive facultative intracellular bacterium, which replicates in the cytoplasm of myeloid cells. Interferon ß (IFNß) has been reported to play an important role in the mechanisms underlying Listeria disease. Although studies in murine cells have proposed the bacteria-derived cyclic-di-AMP to be the key bacterial immunostimulatory molecule, the mechanism for IFNß expression during L. monocytogenes infection in human myeloid cells remains unknown. Here we report that in human macrophages, Listeria DNA rather than cyclic-di-AMP is stimulating the IFN response via a pathway dependent on the DNA sensors IFI16 and cGAS as well as the signalling adaptor molecule STING. Thus, Listeria DNA is a major trigger of IFNß expression in human myeloid cells and is sensed to activate a pathway dependent on IFI16, cGAS and STING.

Altered fraction of regulatory B and T cells is correlated with autoimmune phenomena and splenomegaly in patients with CVID.

Common variable immunodeficiency (CVID) is a heterogeneous primary immunodeficiency disease, leading to recurrent bacterial airway infections and often also autoimmune complications. To shed light on the regulatory lymphocytes from these patients, we analyzed the levels of regulatory B (pro-B10) cell and regulatory T (Treg) cell subpopulations in PBMCs from twenty-six patients diagnosed with CVID using multi-color flowcytometry. Pro-B10 cells were induced by 48h in vitro stimulation prior to analysis. Suppressor function was measured on a subset of patients with splenomegaly and autoimmune complications. The levels of regulatory B and T cells were correlated to clinical manifestations, including autoimmunity, splenomegaly and CVID EUROclass subgroups. We demonstrate a significant association between elevated levels of pro-B10 cells, decreased levels of Tregs and autoimmune phenomena in CVID patients. The finding of marked abnormalities in regulatory lymphocyte populations contribute to our understanding of the pathogenesis of CVID and potentially be valuable in the clinical management and treatment of patients.

Inflammatory cytokines break down intrinsic immunological tolerance of human primary keratinocytes to cytosolic DNA.

Keratinocytes are involved in protecting the body from infections and environmental challenges, but also in inflammatory conditions like psoriasis. DNA has emerged as a potent stimulator of innate immune responses, but there is largely no information of how keratinocytes respond to cytosolic DNA. In this study, we report that human keratinocytes are tolerant to cytoplasmic DNA. However, if treated with inflammatory cytokines, keratinocytes gained the capacity to respond to DNA through a mechanism antagonized by the antimicrobial peptide LL37, proposed to be involved in activation and regulation of skin inflammation. The DNA sensor IFN-inducible protein 16 (IFI16) colocalized with DNA and the signaling molecule stimulator of IFN genes (STING) in the cytoplasm only in cytokine-stimulated cells, correlating with recruitment of the essential kinase TANK-binding kinase 1. Moreover, IFI16 was essential for DNA-driven innate immune responses in keratinocytes. Finally, IFI16 was upregulated in psoriasis skin lesions and localized to the cytoplasm in a subpopulation of cells. Collectively, this work suggests that inflammatory environments in the skin can lead to breakdown of tolerance for DNA in keratinocytes, which could contribute to the development of inflammatory diseases.

Alveolar cytokines and interferon autoantibodies in COVID-19 ARDS.

Background: Type I interferon (IFN-I) and IFN autoantibodies play a crucial role in controlling SARS-CoV-2 infection. The levels of these mediators have only rarely been studied in the alveolar compartment in patients with COVID-19 acute respiratory distress syndrome (CARDS) but have not been compared across different ARDS etiologies, and the potential effect of dexamethasone (DXM) on these mediators is not known. Methods: We assessed the integrity of the alveolo-capillary membrane, interleukins, type I, II, and III IFNs, and IFN autoantibodies by studying the epithelial lining fluid (ELF) volumes, alveolar concentration of protein, and ELF-corrected concentrations of cytokines in two patient subgroups and controls. Results: A total of 16 patients with CARDS (four without and 12 with DXM treatment), eight with non-CARDS, and 15 healthy controls were included. The highest ELF volumes and protein levels were observed in CARDS. Systemic and ELF-corrected alveolar concentrations of interleukin (IL)-6 appeared to be particularly low in patients with CARDS receiving DXM, whereas alveolar levels of IL-8 were high regardless of DXM treatment. Alveolar levels of IFNs were similar between CARDS and non-CARDS patients, and IFNα and IFNω autoantibody levels were higher in patients with CARDS and non-CARDS than in healthy controls. Conclusions: Patients with CARDS exhibited greater alveolo-capillary barrier disruption with compartmentalization of IL-8, regardless of DXM treatment, whereas systemic and alveolar levels of IL-6 were lower in the DXM-treated subgroup. IFN-I autoantibodies were higher in the BALF of CARDS patients, independent of DXM, whereas IFN autoantibodies in plasma were similar to those in controls.

Mpox is a venereological differential diagnosis.

A 34-year-old man, homosexual, came to the clinic of venerology due to severe perianal pain. When examinated, small, eroded vesicles were found perianally. This was interpreted as a primary herpes infection. At the follow-up visit, several vesicular and papular elements were now present on the body. The patient tested positive for mpox. This case confirms that mpox is a relevant differential diagnose in venerology in Denmark.