Interferon type I signature associated with skin disease in juvenile dermatomyositis.

Background: Interferon type I (IFN-I) signaling system hyperactivation plays an important role in the pathogenesis of juvenile dermatomyositis (JDM). Aim of the study: To analyze IFN-I score with disease activity in patients with JDM. Materials and methods: Clinical manifestations laboratory data, and treatment options were analyzed in 15 children with JDM. Disease activity was assessed by CMAS (childhood myositis assessment tool) and CAT (cutaneous assessment tool) scores. IFN I-score was assessed by RT-PCR quantitation of 5 IFN I-regulated transcripts (IFI44L, IFI44, IFIT3, LY6E, MXA1). Results: All patients had skin and muscle involvement, some had a fever (n = 8), swallowing disorders (n = 4), arthritis (n = 5), calcinosis (n = 3), lipodystrophy (n = 2), and interstitial lung disease (n = 5). Twelve patients had elevated IFN I-score and it was correlated with skin disease activity. Ten patients had clinically active disease and the level of IFN I-score and its components were higher than in patients with inactive disease (8.8 vs. 4.2, p = 0.011). IFN I-score was evaluated in nine patients during follow-up. The simultaneous reduction of IFN I-score and its components, CMAS and CAT scores was observed. Conclusion: Skin involvement in refractory JDM is a challenging problem requiring the use of additional medications. Serum IFN I-score might be suggested as the promising biomarker of skin disease activity in JDM patients. Further investigations on patients with JDM and recurrent disease activity are needed, especially concerning biomarkers that determine the response to JAK inhibitors and treatment options for patients who don't respond to them.

Differentiating central nervous system demyelinating disorders: The role of clinical, laboratory, imaging characteristics and peripheral blood type I interferon activity.

Objective: While multiple sclerosis (MS) is considered the cornerstone of autoimmune demyelinating CNS disorders, systemic autoimmune diseases (SADs) are important MS mimickers. We sought to explore whether distinct clinical, laboratory, and imaging characteristics along with quantitation of peripheral blood type I interferon (IFN) activity could aid in differentiating between them. Methods: A total of 193 consecutive patients with imaging features suggesting the presence of CNS demyelinating disease with or without relevant clinical manifestations underwent full clinical, laboratory, and imaging evaluation, including testing for specific antibodies against 15 cellular antigens. Expression analysis of type I IFN-inducible genes (MX-1, IFIT-1, and IFI44) was performed by real-time PCR, and a type I IFN score, reflecting type I IFN peripheral activity, was calculated. After joint neurological/rheumatological evaluation and 1 year of follow-up, patients were classified into MS spectrum and CNS autoimmune disorders. Results: While 66.3% (n = 128) of the patients were diagnosed with MS spectrum disorders (predominantly relapsing-remitting MS), 24.9% (n = 48) were included in the CNS autoimmune group, and out of those, one-fourth met the criteria for SAD (6.7% of the cohort, n = 13); the rest (18.1% of the cohort, n = 35), despite showing evidence of systemic autoimmunity, did not fulfill SAD criteria and comprised the "demyelinating disease with autoimmune features" (DAF) subgroup. Compared to the MS spectrum, CNS autoimmune patients were older, more frequently females, with increased rates of hypertension/hyperlipidemia, family history of autoimmunity, cortical dysfunction, anti-nuclear antibody titers ≥1/320, anticardiolipin IgM positivity, and atypical for MS magnetic resonance imaging lesions. Conversely, lower rates of infratentorial and callosal MRI lesions, CSF T2 oligoclonal bands, and IgG-index positivity were observed in CNS autoimmune patients. Patients fulfilling SAD criteria, but not the DAF group, had significantly higher peripheral blood type I IFN scores at baseline compared to MS spectrum [median (IQR)]: 50.18 (152.50) vs. -0.64 (6.75), p-value: 0.0001. Conclusion: Our study suggests that underlying systemic autoimmunity is not uncommon in patients evaluated for possible CNS demyelination. Distinct clinical, imaging and laboratory characteristics can aid in early differentiation between MS and CNS-involving systemic autoimmunity allowing for optimal therapeutic strategies. Activated type I IFN pathway could represent a key mediator among MS-like-presenting SADs and therefore a potential therapeutic target.

Establishment and application of detection method for interferon stimulated genes expression in children / 中华检验医学杂志

Objective:To establish the detection method for the interferon stimulated genes(ISGs), calculate the cut-off value and test it in clinical practice.Methods:Patients with type I interferonopathies who were admitted to Peking Union Medical College Hospital from November 2017 to September 2021 were chosen as the disease group, and healthy children were included as the control group. A total of 18 children were in the disease group, including 8 males and 10 females, with a median age of 8.5 years for the first test. From them 25 blood specimens were collected. A total of 28 healthy children, aged 1 to 18 years, with a median age of 10.5 years, including 15 males and 13 females, were included in the control group. Blood samples of 34 controls and 18 interferonopathies patients were collected, then total RNA extraction and cDNA synthesis were performed. Real-time quantitative polymerase chain reaction assays were run in duplicate to measure the expression of six ISGs: interferon induced protein with tetratricopeptide repeats 1 (IFIT1), interferon α inducible protein 27 (IFI27), interferon induced protein 44 like (IFI44L), interferon stimulated genes 15 (ISG15), sialic acid binding Ig like lectin 1 (SIGLEC1), and radical S-adenosyl methionine domain containing 2 (RSAD2). The relative abundances of each target transcript was normalized to the expression level of β-Actin and OAZ. The median fold change of the six ISGs was used to create an interferon score (IS) for each individual. Samples with abnormal expressions were removed and the cDNA mix of the remaining samples was used as a calibrator to calculate the IS. We define an abnormal IS as being greater than+2 standard deviations above the mean of controls. Differences in IS between groups were compared using t-test or Mann-Whitney U-test. Results:The mean IS of controls was 1.046, standard 0.755, and the cut-off value was 2.556. A total of 25 samples from 18 interferonopathies patients were tested. The mean value was 27.010 with a 15/18 abnormality rate. Compared with the control group, IS in patients was significantly higher, t=4.247( P=0.000 1). The accuracy, precision, sensitivity, and specificity were 91.30% (42/46), 7.47%(0.084/1.124), 15/18, and 96.43% (27/28), respectively. Conclusion:This study provides a new and reliable method for clinical screening and dynamic monitoring of type Ⅰ interferonopathies by detecting ISGs expression and creating an IS.

Analysis of interferon type I signature for differential diagnosis of diseases of the immune system ( review of literature).

Type 1 interferons (IFN1) are both key molecules of antiviral defense and potent inflammatory mediators. In 2003, increased expression of a variety of interferon 1-regulated genes was observed in a blood cells of patients with systemic lupus erythematosus (SLE). This phenomenon was called the type 1 interferon signature (IFN1-signature). Since then, expression patterns indicating the presence of an IFN1-signature were consistently detected in a range of monogenic and complex autoimmune and autoinflammatory conditions. A quantitative indicator reflecting the degree of hyperactivation of the IFN1 pathway is known as interferon score. This review discusses the possible causes of upregulated expression of interferon 1-induced genes, the laboratory approaches to the interferon score analysis, as well as the practical use of this indicator for the diagnosis of various conditions.

Higher interferon score and normal complement levels may identify a distinct clinical subset in children with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex multi-system disease, characterized by both autoimmune and autoinflammatory clinical and laboratory features. The role of type I interferon (IFN) in SLE has been demonstrated from the 2000s, by gene expression analyses showing significant over-expression of genes related to type I IFN signalling pathway (IFN signature). However, several studies questioned the role of measuring the intensity of IFN signature (IFN score) to chase SLE activity. We would assess if the IFN signature can help the clinical and therapeutic stratification of patients with pediatric SLE. METHODS: We measured the IFN score in peripheral whole blood from a series of subjects with childhood-onset SLE and correlated the results with clinical and laboratory parameters. RESULTS: Thirty-one subjects were included in the study, among which the 87% displayed a positive IFN score. The only significant relation was found for high IFN score in subjects with normocomplementemia. No correlation was observed between IFN score and SLEDAI-2K, BILAG-2004 and SLICC. Patients with high IFN score and normal complement levels also presented lower anti-dsDNA antibodies. CONCLUSIONS: The integration between IFN signature analysis and complement levels may easily distinguish two groups of subjects, in which the autoimmune or autoinflammatory component of the disease seems to be prevalent.

Complexity in unclassified auto-inflammatory disease: a case report illustrating the potential for disease arising from the allelic burden of multiple variants.

BACKGROUND: Despite recent advances in the diagnosis and understanding of many autoinflammatory diseases, there are still a great number of patients with phenotypes that do not fit any clinically- and/or genetically-defined disorders. CASE PRESENTATION: We describe a fourteen-year-old boy who presented at two and a half years of age with recurrent febrile episodes. Over the course of the disease, the episodes increased in frequency and severity, with new signs and symptoms continuing to appear. Most importantly, these included skin changes, splenomegaly and transaminitis. Only partial control of the disease was achieved with anti-IL-1 therapy. Extensive investigation showed generalized inflammation without immune deficiency, with increased levels of serum amyloid A and several pro-inflammatory cytokines including interferon-γ, as well as an increased type I interferon score. Exome sequence analysis identified P369S and R408Q variants in the MEFV innate immunity regulator, pyrin (MEFV) gene and T260 M and T320 M variants in the NLR family pyrin domain containing 12 (NLRP12) gene. CONCLUSION: Patients with unclassified and/or unexplained autoinflammatory syndromes present diagnostic and therapeutic challenges and collectively form a substantial part of every cohort of patients with autoinflammatory diseases. Therefore, it is important to acquire their full genomic profile through whole exome and/or genome sequencing and present their cases to a broader audience, to facilitate characterization of similar patients. A critical mass of well-characterized cases will lead to improved diagnosis and informed treatment.

Comparable type I interferon score determination from PAXgene and Tempus whole blood RNA collection and isolation systems.

OBJECTIVE: Type I interferons (IFN) have important roles in many immune-mediated inflammatory diseases (IMIDs) and are a relatively new therapeutic target. Direct detection of type I IFNs has proved challenging, thus their presence is often inferred from the expression of interferon-stimulated genes (ISGs) and calculation of an interferon score (IS). The objective of this research was to determine if the expression of six common ISGs and subsequent IS were comparable when RNA was derived from the Tempus and PAXgene whole blood RNA collection systems. RESULTS: Whole blood was obtained from ten healthy adults, incubated ex vivo in the absence and presence of recombinant human IFNα then divided into PAXgene and Tempus tubes. Despite reports of tube-specific patterns of gene expression, quantitative PCR (qPCR) analysis revealed no significant differences between PAXgene and Tempus tubes in either the homeostatic or IFNα-induced expression of six ISGs (IFI27, IFI44L, IFIT1, ISG15, RSAD2, SIGLEC1). Overall there was a strong correlation in the IS between unstimulated (r = 0.92, p = 0.0005) and IFNα-stimulated (r = 0.71, p = 0.0268) samples derived from the PAXgene and Tempus tubes.

Type I Interferon Signature in Primary Antiphospholipid Syndrome: Clinical and Laboratory Associations.

Background: Increased expression of type I interferon (IFN)-regulated genes has been described in blood and tissue cells from patients with systemic lupus erythematosus (SLE) and other rheumatic disorders. Only isolated studies have examined the type I IFN gene expression in antiphosholipid syndrome (APS), while efforts to evaluate associations with APS-related factors are scarce. Objective: Our aim was to investigate the type I IFN signature in patients with primary APS (PAPS), SLE/APS, and SLE in comparison with healthy controls, and to evaluate associations with disease-related characteristics. Methods: We measured the type I IFN score, derived from relative expressions of three IFN-inducible genes (MX-1, IFIT-1, and IFI-44) in peripheral blood mononuclear cells from 55 patients with PAPS, 34 with SLE/APS, 48 with SLE, and 28 controls. In patients with PAPS, we performed multivariate regression to examine associations of type I IFN score with their clinical, laboratory and treatment characteristics. Results: Type I IFN score was increased in all patient groups vs. controls (p = 0.028, p = 0.027, p = 0.028 for PAPS, SLE/APS, and SLE, respectively). IFI-44 had the most pronounced expression. In patients with PAPS, multivariate linear regression revealed positive associations of type I IFN score with female gender (b-coefficient = 0.49; 95% CI 0.04, 0.94; p = 0.034) and IgG or IgM anti-ß2GPI antibodies (b-coefficient = 0.53; 95% CI 0.10, 0.96; p = 0.017), and negative associations with age (b-coefficient = -0.02/year; 95% CI -0.04, -0.01; p = 0.027) and hydroxychloroquine use (b-coefficient = -0.51; 95% CI-0.96, -0.06; p = 0.027). Conclusion: Type I IFN score is increased in PAPS and correlated positively with anti-ß2GPI antibodies and negatively with hydroxychloroquine use.