Update on ocular manifestations of the main monogenic and polygenic autoinflammatory diseases.

Autoinflammatory diseases include disorders with a genetic cause and also complex syndromes associated to polygenic or multifactorial factors. Eye involvement is present in many of them, with different extent and severity. The present review covers ophthalmological lesions in the most prevalent monogenic autoinflammatory diseases, including FMF (familial Mediterranean fever), TRAPS (TNF receptor-associated periodic syndrome), CAPS (cryopyrin-associated periodic syndromes), Blau syndrome, DADA2 (deficiency of adenosine deaminase 2), DITRA (deficiency of the interleukin-36 receptor antagonist), other monogenic disorders, including several ubiquitinopathies, interferonopathies, and the recently described ROSAH (retinal dystrophy, optic nerve edema, splenomegaly, anhidrosis, and headache) syndrome, and VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. Among polygenic autoinflammatory diseases, ocular manifestations have been reviewed in Behçet's disease, PFAPA (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis) syndrome, Still's disease and autoinflammatory bone diseases, which encompass CRMO (chronic recurrent multifocal osteomyelitis) and SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome.

The role of bilirubin as a biomarker of rheumatic diseases: a systematic review and meta-analysis.

The identification of novel, yet easily measurable biomarkers of inflammation and oxidative stress might assist in the diagnosis and management of patients with rheumatic diseases (RDs). We conducted a systematic review and meta-analysis of studies investigating the circulating concentrations of bilirubin, the end product of heme metabolism and a potent endogenous antioxidant with anti-inflammatory properties, in patients with RDs and healthy controls. The electronic databases PubMed, Scopus, and Web of Science were searched from inception to 31 December 2023 for relevant articles. We evaluated the risk of bias and the certainty of evidence using the Joanna Briggs Checklist and the Grades of Recommendation, Assessment, Development, and Evaluation Working Group system, respectively. In 17 eligible studies, all with low risk of bias, compared to controls, patients with RDs had significantly lower concentrations of total bilirubin (standard mean difference, SMD=-0.68, 95% CI -0.91 to -0.44, p<0.001; I2 = 92.5%, p<0.001; low certainty of evidence), direct (conjugated) bilirubin (SMD=-0.67, 95% CI -0.92 to -0.41, p<0.001; I2 = 81.7%, p<0.001; very low certainty of evidence), and the active antioxidant and anti-inflammatory indirect (unconjugated) form of bilirubin (SMD=-0.71, 95% CI -1.18 to -0.24, p=0.003; I2 = 95.1%, p<0.001; very low certainty of evidence). The results of the meta-analysis were stable in sensitivity analysis. In meta-regression, there were no significant associations between the SMD of total bilirubin and several clinical and demographic characteristics, including age, male to female ratio, number of participants, liver enzymes and erythrocyte sedimentation rate. In subgroup analysis, the SMD of total bilirubin was significant across a range of RDs, including rheumatoid arthritis, systemic lupus erythematosus, primary Sjögren syndrome, and myositis. Therefore, the results of our systematic review and meta-analysis suggests that the reductions in bilirubin concentrations observed in patients with RDs reflect a state of impaired antioxidant and anti-inflammatory defence due to bilirubin consumption and highlight the promising role of this endogenous product as a biomarker of RDs. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023500649.

Yao syndrome: a novel systemic autoinflammatory disease with cutaneous manifestations.

Yao syndrome (YAOS) is a novel systemic autoinflammatory disease linked to the nucleotide-binding oligomerization domain (NOD2) gene. It is characterized by periodic fevers, gastrointestinal (GI) symptoms, arthritis, and dermatitis, among other symptoms. A sparse literature exists on this disease, and little is known about its dermatological manifestations. A review of available literature was performed to characterize the cutaneous manifestations of Yao syndrome. Cutaneous manifestations were documented in 85.7% of patients, with common characteristic descriptions of erythematous patches and plaques involving the face, trunk, abdomen, and extremities. Based on our review of treatment modalities employed for Yao syndrome, prednisone is an appropriate initial approach, with oral sulfasalazine and other disease-modifying antirheumatic drugs serving as appropriate secondary options. YAOS should be considered in the differential diagnosis of patients presenting with a dermatitic rash, especially in the context of concurrent articular symptoms, periodic fever, and GI symptoms.

A rare missense p.C125Y mutation in the TNFRSF1A gene identified in a Chinese family with tumor necrosis factor receptor-associated periodic fever syndrome.

Background: Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is a rare autosomal dominant disorder with a low incidence in Asia. The most frequent clinical manifestations include fever, rash, myalgia, joint pain and abdominal pain. Misdiagnosis rates are high because of the clinical and genetic variability of the disease. The pathogenesis of TRAPS is complex and yet to be fully defined. Early genetic diagnosis is the key to precise treatment. Methods: In this study, a Chinese family with suspected TRAPS were analyzed by genome-wide SNP genotyping, linkage analysis and targeted sequencing for identification of mutations in causative genes. To study the pathogenicity of the identified gene mutation, we performed a conservation analysis of the mutation site and protein structure analysis. Flow cytometry was used to detect TNFRSF1A shedding and quantitative real-time PCR were used to assess the activation of unfolded protein response (UPR) in the mutation carriers and healthy individuals. Results: A typical TRAPS family history, with a pattern of autosomal dominant inheritance, led to the identification of a rare mutation in the TNFRSF1A gene (c.G374A [p.Cys125Tyr]) with unknown significance. The patient responded well to corticosteroids, and long-term therapy with colchicine effectively reduced the inflammatory attacks. No amyloid complications occurred during the 6-year follow-up. In silico protein analysis showed that the mutation site is highly conversed and the mutation prevents the formation of intrachain disulfide bonds in the protein. Despite a normal shedding of the TNFRSF1A protein from stimulated monocytes in the TRAPS patients with p.C125Y mutation, the expression of CHOP and the splicing of XBP1 was significantly higher than healthy controls, suggesting the presence of an activation UPR. Conclusion: This is the first report of a Chinese family with the rare p.C125Y mutation in TNFRSF1A. The p.C125Y mutation does not result in aberrant receptor shedding, but instead is associated with an activated UPR in these TRAPS patients, which may provide new insights into the pathogenesis of this rare mutation in TRAPS.

PSTPIP1-associated myeloid-related proteinemia inflammatory (PAMI) syndrome: A case report and review of the literature.

PSTPIP1-associated myeloid-related proteinemia inflammatory (PAMI) syndrome is a rare autoinflammatory disorder often arising in pediatric patients. We present a case of an 18-year-old female with a past medical history of growth failure, immunoglobulin A nephropathy, and inflammatory arthritis who presented to a pediatric dermatology clinic with findings of acne, psoriasiform dermatitis, and hidradenitis suppurativa, whose clinical, genetic, and laboratory findings were most consistent with PAMI syndrome. We conducted a literature review to better characterize this rare condition in the context of dermatologic findings. Recognition of the distinctive skin findings seen in PAMI syndrome can help distinguish it from other inflammatory disorders, enabling expedited diagnosis and treatment.

CRP and sCD25 help distinguish between adult-onset Still's disease and HLH.

OBJECTIVE: Adult-onset Still's disease (AOSD) and secondary hemophagocytic lymphohistiocytosis (sHLH) are both hyperferritinemic cytokine storm syndromes that can be difficult to distinguish from each other in hospitalized patients. The objective of this study was to compare the inflammatory markers ferritin, D-dimer, C-reactive protein (CRP), and soluble CD25 (sCD25) in patients with AOSD and sHLH. These four markers were chosen as they are widely available and represent different aspects of inflammatory diseases: macrophage activation (ferritin); endothelialopathy (D-dimer); interleukin-1/interleukin-6/tumour necrosis factor elevation (CRP) and T cell activation (sCD25). METHODS: This was a single-center retrospective study. Patients diagnosed by the Hematology service at Vancouver General Hospital for AOSD or sHLH from 2009 to 2023 were included. RESULTS: There were 16 AOSD and 44 sHLH patients identified. Ferritin was lower in AOSD than HLH (median 11 360 µg/L vs. 29 020 µg/L, p = .01) while D-dimer was not significantly different (median 5310 mg/L FEU vs. 7000 mg/L FEU, p = .3). CRP was higher (median 168 mg/L vs. 71 mg/L, p <.01) and sCD25 was lower (median 2220 vs. 7280 U/mL, p = .004) in AOSD compared to HLH. The combined ROC curve using CRP >130 mg/L and sCD25< 3900 U/mL to distinguish AOSD from HLH had an area under the curve (AUC) of 0.94 (95% confidence interval 0.93-0.97) with sensitivity 91% and specificity 93%. CONCLUSIONS: These findings suggest that simple, widely available laboratory tests such as CRP and sCD25 can help clinicians distinguish AOSD from HLH in acutely ill adults with extreme hyperferritinemia. Larger studies examining a wider range of clinically available inflammatory biomarkers in a more diverse set of cytokine storm syndromes are warranted.

Anakinra in Pyogenic Arthritis, Acne, Pyoderma Gangrenosum, and Suppurative Hidradenitis (PAPASH) Spectrum Disorder: A Case Report and Literature Review.

Pyogenic arthritis, acne, pyoderma gangrenosum, and suppurative hidradenitis (PAPASH); pyogenic arthritis, pyoderma gangrenosum (PG), and acne; PG, acne, hidradenitis suppurativa; and PG, acne, spondylarthritis (PASS) are all part of a spectrum of autoinflammatory disorders that share similar pathogenesis. They are related to various mutations in the proline-serine-threonine phosphatase interacting protein 1, leading to dysregulation of the innate immune system and overproduction of interleukin (IL)-1, IL-17, and IL-23 and tumor necrosis factor (TNF)-α. Targeting these cytokines with biologics plays an important role in treatment. Here, we are describing the case of a young male with PAPASH syndrome who was treated with TNF-α and IL-1 inhibitor.

The Multifaceted Complexity of Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS): A Case Report Highlighting Atypical Gastrointestinal Manifestations.

BACKGROUND: Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS) is an autosomal dominant autoinflammatory disorder stemming from mutations in the TNFRSF1A gene affecting the tumor necrosis factor receptor (TNFR)-1. These mutations lead to dysregulated inflammatory responses, primarily mediated by augmented interleukin (IL)-1ß release. CASE PRESENTATION: We present the case of a 29-year-old woman with a history of recurrent febrile episodes, abdominal pain, and joint manifestations, eventually diagnosed with TRAPS following genetic testing revealing a heterozygous R92Q mutation in TNFRSF1A. Further genetic examinations unveiled additional clinically significant mutations, complicating the clinical picture. Our patient exhibited delayed colonic transit time and right colonic amyloidosis, a rare complication. Surgical intervention was required for overwhelming intestinal obstruction, revealing mucosal atrophy and dense lymphocytic infiltrates on histological examination. DISCUSSION: Gastrointestinal involvement in TRAPS is common but can present diagnostic challenges. Following colon resection, histological examination revealed amyloid deposition, underscoring the importance of a comprehensive evaluation of these patients. Isolated colic amyloidosis has significant diagnostic and prognostic implications, warranting cautious monitoring and tailored management strategies. Treatment of TRAPS typically involves anti-inflammatory agents such as IL-1 inhibitors, with our patient experiencing clinical improvement on anakinra and canakinumab. CONCLUSION: This case report emphasizes the diverse manifestations of TRAPS and the importance of recognizing gastrointestinal complications, particularly isolated colic amyloidosis. Comprehensive evaluation, including histological examination, is crucial for identifying atypical disease presentations and guiding management decisions. Continued research is needed to elucidate the underlying mechanisms and optimize treatment strategies for TRAPS and its associated complications.

TNFRSF11A variants contribute to systemic autoinflammatory diseases: A case series of 12 patients.

BACKGROUND: Limited evidence suggests that variants in TNFRSF11A gene, encoding RANK, may contribute to systemic autoinflammatory disease (SAID). AIM/METHODS: To estimate the prevalence of TNFRSF11A variants in a cohort of patients with SAIDs screened for 26 related genes and describe the disease phenotypic expression. RESULTS: A total of 12 out of 167 patients, 7 males, aged (median) 38 years at disease onset, yielded at least one TNFRSF11A rare variant. All patients carried a coexisting variant in at least one other SAID-related gene, most frequently MEFV (6 patients), but also TNFRSF1A, NOD2, NLRP3, NLRP7, MVK, IL36RN, RBCK1, PLCG2 and PSMB8. SAID episodes lasting (median) 9 days manifested with high grade fever (91%), myalgias (75%), malaise (67%), serositis (58%), arthralgias/arthritis (58%), gastrointestinal involvement (33%), and rash (25%), and responded to corticosteroids. The most common initial clinical diagnosis was TNF-associated periodic fever syndrome (TRAPS), which was, however, confirmed, in only one patient. The emergence of MEFV variations supported the diagnosis of atypical Familial Mediterranean Fever in two cases, whereas the diagnosis of Yao syndrome was speculated in two patients with NOD2 variants. The presence of atypical disease and the inability of defining diagnosis in the remaining 7 patients, supported the possible involvement of TNFRSF11A variants in the phenotypic expression of SAIDs. CONCLUSION: TNFRSF11A variants, occurring in 7% of SAID patients always in combination with other SAID-related gene variants, contribute to the development of an autoinflammatory syndrome resembling to TRAPS. Additional studies to confirm novel pathogenic SAID pathways are clearly warranted.

NLRP3 Inflammasome in Autoinflammatory Diseases and Periodontitis Advance in the Management.

Inflammatory chemicals are released by the immune system in response to any perceived danger, including irritants and pathogenic organisms. The caspase activation and the response of inflammation are governed by inflammasomes, which are sensors and transmitters of the innate immune system. They have always been linked to swelling and pain. Research has mainly concentrated on the NOD-like protein transmitter 3 (NLRP3) inflammasome. Interleukin (IL)-1 and IL-18 are pro-inflammatory cytokines that are activated by the NOD-like antibody protein receptor 3 (NLRP3), which controls innate immune responses. The NLRP3 inflammasome has been associated with gum disease and other autoimmune inflammatory diseases in several studies. Scientists' discovery of IL-1's central role in the pathophysiology of numerous autoimmune disorders has increased public awareness of these conditions. The first disease to be connected with aberrant inflammasome activation was the autoinflammatory cryopyrin-associated periodic syndrome (CAPS). Targeted therapeutics against IL-1 have been delayed in development because their underlying reasons are poorly understood. The NLRP3 inflammasome has recently been related to higher production and activation in periodontitis. Multiple periodontal cell types are controlled by the NLRP3 inflammasome. To promote osteoclast genesis, the NLRP3 inflammasome either increases receptor-activator of nuclear factor kappa beta ligand (RANKL) synthesis or decreases osteoclast-promoting gene (OPG) levels. By boosting cytokines that promote inflammation in the periodontal ligament fibroblasts and triggering apoptosis in osteoblasts, the NLRP3 inflammasome regulates immune cell activity. These findings support further investigation into the NLRP3 inflammasome as a therapeutic target for the medical treatment of periodontitis. This article provides a short overview of the NLRP3 inflammatory proteins and discusses their role in the onset of autoinflammatory disorders (AIDs) and periodontitis.

38.3 Primary Immunodeficiencies: When is it not just "JIA".

Juvenile Idiopathic Arthritis (JIA) is sometimes considered a diagnosis of exclusion as the name signifies that no cause is evident for this form of arthritis. Despite this JIA has some classical clinical features and many categories are defined based on the phenotype. Since there is no diagnostic test for JIA, diseases that can mimic JIA, including Primary Immunodeficiencies (PID) can sometimes be misdiagnosed as JIA. The clues to suspecting PIDs are early age of onset, presence of family history, increased susceptibility to infections, unusual features like urticaria, interstitial lung disease, sensorineural hearing loss and poor response to conventional therapy, amongst others. This review will highlight the basics of PIDs and will discuss PIDs that can present with arthritis and hence can be confused with JIA.

A pilot study of childhood-onset Takayasu arteritis using whole exome sequencing suggests oligogenic inheritance involving classical complement, collagen, and autoinflammatory pathways.

Takayasu arteritis (TA) is a chronic granulomatous inflammatory disease affecting the aorta and its branches. Paediatric TA (pTA) may present from 6 months after birth till the adolescent age group. Genetics and pathogenesis of pTA are not fully understood. Earlier studies reported monogenic mutation in NOD2, XIAP, and STAT1 genes in patients with pTA. TA, a relatively rare disease, is more common in geographical pockets, including India. We hypothesized that South Asian patients with pTA, namely, those of Indian subcontinent origin, may have clinically relevant and unique pathogenic variants involving one or more genes, especially those linked to genetically driven vasculitic illnesses, including autoinflammatory pathologies. Children with pTA fulfilling EULAR/PRINTO/PReS classification criteria and presenting with clinical symptoms to the Paediatric Rheumatology clinic of Christian Medical College, Vellore, were included. Blood samples were collected after getting informed consent from parents or guardians and assent forms from children. DNA was extracted from whole blood using the Qiagen DNA extraction kit. Initially, the common variant in Indian population, namely, ADA2 c.139G > A; p.Gly47Arg, was screened, followed by whole exome sequencing. Fourteen children were recruited for the study. Median age of patients was 11 years (4 months-14 years) with a male-to-female ratio of 4:10. Distribution of angiographic subsets by Numano's classification of included children were as follows: type 5 (n = 7), type 4 (n = 5), and type 3 (n = 2). We identified novel variants in ten different genes. This include variants in genes of classical complement pathway, namely, C2, C3, C6, C7, and C9, and other genes, namely, CYBA, SH3BP2, GUCY2C, CTC1, COL5A1, and NLPR3. Two of 14 patients have heterozygous pathogenic variants; this implies that combination of heterozygous variants in C3 and COL5A1 might lead to disease development, suggesting digenic inheritance. One patient has a homozygous variant in CYBA. None of the patients were identified to have ADA2 variants. Whole exome sequencing reveals combination of rare variants in genes C3, COL5A1, and CYBA associated with disease development in children with Takayasu Arteritis. Key Points • We identified novel variants in genes of classical complement pathway, namely, C2, C3, C6, C7, and C9, and other genes, namely, CYBA, SH3BP2, GUCY2C, CTC1, COL5A1, and NLPR3. • Two of 14 patients have heterozygous pathogenic variants in C3 and COL5A1; this may have implications in disease development, suggesting digenic inheritance. • One patient has homozygous variant in CYBA. • None of the patients were identified to have ADA2 variants.

Urticarial Vasculitis.

Urticarial vasculitis is a rare autoimmune disorder characterized by persistent edematous papules and plaques on the skin that last longer than 24 hours, often accompanied by systemic symptoms such as joint pain and fever. Unlike common urticaria, this condition involves inflammation of small blood vessels, leading to more severe and long-lasting skin lesions with a tendency to leave a bruiselike appearance. Diagnosis is challenging and may require a skin biopsy. Associated with underlying autoimmune diseases, treatment involves managing symptoms with medications such as antihistamines and corticosteroids, addressing the immune system's dysfunction, and treating any concurrent autoimmune conditions.

Coexistence of systemic sclerosis and cryopyrin-associated periodic syndrome.

Systemic sclerosis (SSc) and cryopyrin-associated periodic syndrome (CAPS) are distinct clinical entities belonging to the autoimmune and autoinflammatory diseases, respectively. The coexistence of the two entities has rarely been reported and is poorly characterized. Here, we described a case of a 38-year-old Japanese woman diagnosed with anti-centromere antibody-positive SSc and CAPS carrying the pathogenic mutation in the NLRP3 gene, with a detailed autoantibody profile by a high-throughput comprehensive protein array covering approximately 90% of the human transcriptome. The clinical manifestations of the patient were typical of both SSc and CAPS. Comprehensive autoantibody profiling identified 65 autoantibodies in the patient's serum and 78 autoantibodies in the serum of her daughter with CAPS, who carried the same NLRP3 mutation as the patient. SSc-associated autoantibodies (anti-DBT, anti- CENP-B, and anti-CENP-A) and anti-CD320 antibody were detected at high levels only in the patient's serum, while autoantibodies to the following four proteins were detected in the sera of both the patient and her daughter: TRIM21, LIMS1, CLIP4, and KAT2A. The TRRUST enrichment analysis identified NF-κB1 and RelA as overlapping key transcription factors that regulate the genes encoding proteins to which autoantibodies were detected in the patient and her daughter, therefore the autoantibody profile of the patient cannot be solely attributed to SSc, but may also be influenced by CAPS. Although autoimmune and autoinflammatory diseases are considered to be at opposite ends of the immunological spectrum, detailed autoantibody profiling may reveal a unique immunological landscape in an overlapping case of the two entities.

Overview of Systemic Autoinflammatory Diseases.

Systemic autoinflammatory diseases (SAID) are a growing family of disorders of the innate immune system. Over the years, there have been changes in the definition, classification and nomenclature of SAID as new syndromes and pathophysiologic mechanisms continue to be described. Recognizing the clinical manifestations of SAID is important for their early diagnosis and management. The field continues to advance with potential new therapies underway.

Drug-Induced Undifferentiated Connective Tissue Disease in a Two-Year-Old Girl: A Manifestation of Factitious Disorder Imposed on Another (FDIA).

Factitious disorder imposed on another (FDIA), formerly known as Munchausen syndrome by proxy (MSBP), constitutes a form of child abuse wherein a caregiver fabricates or induces illness in a person under their care or supervision. Here, we present a case of a two-year-old girl with signs and symptoms suggestive of undifferentiated connective tissue disease (UCTD) and probable autoinflammatory disease, which was a manifestation of FDIA. The patient manifested recurrent febrile episodes and presented with hepatosplenomegaly, elevated inflammatory markers, and mesangial proliferative glomerulonephritis. Regardless of extensive medical interventions, including corticosteroids and immunosuppressive therapy, the patient's condition failed to improve until the caregiver was isolated from the patient. Upon questioning, the caregiver admitted to having administered pyrogenal, an immunomodulator, to induce symptoms. This case highlights the challenges and difficulties of diagnosing and managing FDIA-associated illnesses, drawing attention to the importance of considering this diagnosis in cases of unexplained or recurrent fever in children.

Inflammation in Fabry disease: stages, molecular pathways, and therapeutic implications.

Fabry disease, a multisystem X-linked disorder caused by mutations in the alpha-galactosidase gene. This leads to the accumulation of globotriaosylceramide (Gb3) and globotriaosylsphingosine (Lyso-Gb3), culminating in various clinical signs and symptoms that significantly impact quality of life. Although treatments such as enzyme replacement, oral chaperone, and emerging therapies like gene therapy exist; delayed diagnosis often curtails their effectiveness. Our review highlights the importance of delineating the stages of inflammation in Fabry disease to enhance the timing and efficacy of diagnosis and interventions, particularly before the progression to fibrosis, where treatment options are less effective. Inflammation is emerging as an important aspect of the pathogenesis of Fabry disease. This is thought to be predominantly mediated by the innate immune response, with growing evidence pointing towards the potential involvement of adaptive immune mechanisms that remain poorly understood. Highlighted by the fact that Fabry disease shares immune profiles with systemic autoinflammatory diseases, blurring the distinctions between these disorders and highlighting the need for a nuanced understanding of immune dynamics. This insight is crucial for developing targeted therapies and improving the administration of current treatments like enzyme replacement. Moreover, our review discusses the complex interplay between these inflammatory processes and current treatments, such as the challenges posed by anti-drug antibodies. These antibodies can attenuate the effectiveness of therapies, necessitating more refined approaches to mitigate their impact. By advancing our understanding of the molecular changes, inflammatory mediators and causative factors that drive inflammation in Fabry disease, we aim to clarify their role in the disease's progression. This improved understanding will help us see how these processes fit into the current landscape of Fabry disease. Additionally, it will guide the development of more effective diagnostic and therapeutic approaches, ultimately improving patient care.

Assessment of interleukin-18 gene polymorphism and serum levels in cutaneous lichen planus.

BACKGROUND: Lichen planus (LP) is a chronic inflammatory disease with uncertain etiology. Interleukin-18 (IL-18) is an interferon gamma (INFγ) inducing agent. It is a pro-inflammatory cytokine that was found to play a role in the pathogenesis of some autoimmune disorders. MATERIAL AND METHODS: This study included 50 patients with classic cutaneous lichen planus (CLP) and 50 healthy volunteers serving as controls. Venous blood samples were withdrawn from the study subjects under complete aseptic precautions. Blood samples were examined for single nucleotide polymorphisms (SNPs) of IL-18 gene at promoter -137(G/C) and -656 (G/T) using polymerase chain reaction (PCR) and IL-18 level was assessed using enzyme linked immunosorbent assay (ELISA). RESULTS: The mean level of IL-18 was significantly higher in CLP patients (31.63 ± 4.90) compared to control subjects (13.95 ± 6.82). Significantly high levels of IL-18 were found among patients with diabetes, hypertension (p < 0.01 in both). HCV positive patients and patients with both OLP and CLP also expressed higher levels of IL-18. Genotypic and allelic distribution at position -137(G/C) showed that the genotype GG was present at significantly higher frequency in cases (58%) compared to controls (28.0%). On the other hand the CC genotype at position -137 was significantly higher in the controls (28%) as compared to CLP cases (6%). Polymorphism of IL-18 at position -656(G/T) showed no significant difference between cases and controls. No significant difference could be detected in IL-18 level between different genotypic variants at position -137(G/C) and -656(G/T). CONCLUSION: IL-18 may play important role in pathogenesis of LP. Elevated IL-18 levels could be part of the pro-inflammatory autoimmune process in LP. The presence of OLP, HCV, diabetes and hypertension is associated with higher production of IL-18. IL-18 promotor region -137(G/C) polymorphism might be a factor that increase the risk of development of lichen planus in Egyptian patients.

Selection and evaluation of single domain antibody against p19 subunit of IL-23 by phage display for potential use as an autoinflammatory therapeutic.

IL-23 is a double-subunit cytokine that plays an important role in shaping the immune response. IL-23 was found to be associated with several autoinflammatory diseases by generating sustained inflammatory loops that lead to tissue damage. Antibody neutralization of IL-23 was proven to be effective in ameliorating associated diseases. However, antibodies as large proteins have limited tissue penetration and tend to elicit anti-drug antibodies. Additionally, anti-IL-23 antibodies target only one subunit of IL-23 leaving the other one unneutralized. Here, we attempted to isolate a recycling single domain antibody by phage display. One of IL-23 subunits, p19, was expressed in E. coli fused to Gamillus protein to stabilize the α-helix-only p19. To remove Gamillus binders, two biopanning methods were investigated, first, preselection with Gamillus and second, challenge with IL-23 then on the subsequent round challenge with p19-Gam. The isolation of calcium-dependent and pH-dependent recycling binders was performed with EDTA and citrate buffers respectively. Both methods of panning failed to isolate high-affinity and specific p19 recycling binders, while from the second panning method, a high affinity and specific p19 standard binder, namely H11, was successfully isolated. H11 significantly inhibited the gene expression of IL-17 and IL-22 in IL-23-challenged PBMCs indicating H11 specificity and neutralizing ability for IL-23. The new binder due to its small size can overcome antibodies limitations, also, it can be further engineered in the future for antigen clearance such as fusing it to cell penetrating peptides, granting H11 the ability to clear excess IL-23 and enhancing its potential therapeutic effect.