NOD2 Research Articles

Distinct NOD2 mutations reported in three families with Blau syndrome (BS) from a single center in India - Case series and review of literature

ObjectiveBlau syndrome (BS), considered a rare pediatric autoinflammatory disease, is characterised by a triad of granulomatous arthritis, dermatitis and uveitis. Here we present a tale of three families visited in our outpatient department in the last two years (2020−2022) where more than one member was affected with either skin, ophthalmological and joint involvement with either biopsy-proven granuloma or genetic mutation at NOD2 gene suggesting the diagnosis of BS. Case seriesThe first family had three affected members where the mother and her two children had skin changes, polyarthritis and a pathogenic mutation in NOD2 gene (exon 4, c.1000C > T, p.Arg334Trp) suggesting BS. The second family had two affected members where both mother and her son had uveitis, skin changes with NOD2 mutation at exon 4 with c.1147G > A (p Glu 383 Lys) variant. The son also had polyarthritis and his skin biopsy was suggestive of granulomatous inflammation. In the third family with two affected members, we found a mutation in NOD2 on exon 4 (c 1324C > T, p.Lys 442 Phe) which was described as pathogenic with only one report published till date. ConclusionThese three cases presented to us within the last two years and led to a diagnosis of BS in three other family members with discrete mutations (commonest to rarest) on the NOD2 gene in the three families.

Targeting Desulfovibrio vulgaris flagellin-induced NAIP/NLRC4 inflammasome activation in macrophages attenuates ulcerative colitis

IntroductionThe perturbations of gut microbiota could interact with excessively activated immune responses and play key roles in the etiopathogenesis of ulcerative colitis (UC). Desulfovibrio, the most predominant sulfate reducing bacteria (SRB) resided in the human gut, was observed to overgrow in patients with UC. The interactions between specific gut microbiota and drugs and their impacts on UC treatment have not been demonstrated well. ObjectivesThis study aimed to elucidate whether Desulfovibrio vulgaris (D. vulgaris, DSV) and its flagellin could activate nucleotide-binding oligomerization domain-like receptors (NLR) family of apoptosis inhibitory proteins (NAIP) / NLR family caspase activation and recruitment domain-containing protein 4 (NLRC4) inflammasome and promote colitis, and further evaluate the efficacy of eugeniin targeting the interaction interface of D. vulgaris flagellin (DVF) and NAIP to attenuate UC. MethodsThe abundance of DSV and the occurrence of macrophage pyroptosis in human UC tissues were investigated. Colitis in mice was established by dextran sulfate sodium (DSS) and gavaged with DSV or its purified flagellin. NAIP/NLRC4 inflammasome activation and macrophage pyroptosis were evaluated in vivo and in vitro. The effects of eugeniin on blocking the interaction of DVF and NAIP/NLRC4 and relieving colitis were also assessed. ResultsThe abundance of DSV increased in the feces of patients with UC and was found to be associated with disease activity. DSV and its flagellin facilitated DSS-induced colitis in mice. Mechanistically, RNA sequencing showed that gene expression associated with inflammasome complex and pyroptosis was upregulated after DVF treatment in macrophages. DVF was further demonstrated to induce significant macrophage pyroptosis in vitro, depending on NAIP/NLRC4 inflammasome activation. Furthermore, eugeniin was screened as an inhibitor of the interface between DVF and NAIP and successfully alleviated the proinflammatory effect of DVF in colitis. ConclusionTargeting DVF-induced NAIP/NLRC4 inflammasome activation and macrophage pyroptosis ameliorates UC. This finding is of great significance for exploring the gut microbiota-host interactions in UC development and providing new insights for precise treatment.

Genetic inhibition of CARD9 accelerates the development of atherosclerosis in mice through CD36 dependent-defective autophagy

Caspase recruitment-domain containing protein 9 (CARD9) is a key signaling pathway in macrophages but its role in atherosclerosis is still poorly understood. Global deletion of Card9 in Apoe-/- mice as well as hematopoietic deletion in Ldlr-/- mice increases atherosclerosis. The acceleration of atherosclerosis is also observed in Apoe-/-Rag2-/-Card9-/- mice, ruling out a role for the adaptive immune system in the vascular phenotype of Card9 deficient mice. Card9 deficiency alters macrophage phenotype through CD36 overexpression with increased IL-1β production, increased lipid uptake, higher cell death susceptibility and defective autophagy. Rapamycin or metformin, two autophagy inducers, abolish intracellular lipid overload, restore macrophage survival and autophagy flux in vitro and finally abolish the pro-atherogenic effects of Card9 deficiency in vivo. Transcriptomic analysis of human CARD9-deficient monocytes confirms the pathogenic signature identified in murine models. In summary, CARD9 is a key protective pathway in atherosclerosis, modulating macrophage CD36-dependent inflammatory responses, lipid uptake and autophagy.

KLF5‑mediated expression of CARD11 promotes the progression of gastric cancer.

Caspase recruitment domain-containing protein 11 (CARD11) has been reported as functioning in multiple types of cancers. In the present study, the role and mechanism of CARD11 in gastric cancer was investigated. First, CARD11 expression in gastric cancer tissues and the association of CARD11 with overall survival were analyzed by the encyclopedia of RNA interactomes database. CARD11 expression in gastric cancer cells was detected by western blotting and reverse transcription-quantitative PCR analyses. After CARD11 silencing, cell proliferation was evaluated by Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine staining and flow cytometry analysis. Wound healing and Transwell assays were used to measure the capacities of cell migration and invasion. Additionally, the expression levels of epithelial-mesenchymal transition (EMT)-related proteins and mTOR-related proteins were detected by western blot analysis. HumanTFDB predicted the binding of the transcription factor Krüppel-like factor 5 (KLF5) to the CARD11 promoter, which was confirmed by dual luciferase reporter and chromatin immunoprecipitation assays. To explore the regulatory effects between KLF5 and CARD11, KLF5 was overexpressed to perform the rescue experiments in gastric cancer cells with CARD11 silencing. Results revealed that CARD11 was highly expressed in gastric cancer and was associated with poor prognosis. CARD11 interference inhibited the proliferation of gastric cancer cells and induced cell cycle arrest. Additionally, CARD11 silencing suppressed the migration, invasion and EMT of gastric cancer cells, accompanied by upregulated E-cadherin expression and downregulated N-cadherin and vimentin expression. Moreover, the transcription factor KLF5 positively regulated the transcription of CARD11 in gastric cancer. KLF5 overexpression reversed the effects of interference of CARD11 expression in gastric cancer cells to promote their proliferation, migration, invasion and EMT. KLF5 overexpression also led to a reduction in cell cycle arrest. Finally, interference of CARD11 expression suppressed the mTOR pathway, which was activated by KLF5. In conclusion, KLF5-mediated CARD11 promoted the proliferation, migration and invasion of gastric cancer cells.

Blau syndrome with persistent fetal vasculature: a case report

BackgroundBlau Syndrome (BS) is a rare autosomal dominant noncaseous granulomatous disease caused by mutations in the NOD2 gene. The disease is characterized by granulomatous dermatitis, symmetrical arthritis, and uveitis, which, if left untreated, can progress to blindness. The diagnosis of BS can be challenging because of its rarity and overlap with other rheumatologic disorders. Early detection of ocular involvement is critical to prevent vision loss and improve the prognosis of patients with BS.Case presentationIn this report, we present a case of a five-year-old Chinese girl diagnosed with BS one year ago after presenting with a systemic rash and urinary calculi. Genetic testing was recommended by a physician, and a heterozygous mutation of the NOD2 gene c.1538T > C (p.M513T) was identified. Eight months ago, due to bilateral corneal punctate opacity, we had examined and diagnosed bilateral uveitis, bilateral corneal zonal degeneration, persistent fetal vasculature (PFV) in the right eye, and perivascular granuloma in the right eye. As a result, Vitrectomy was performed on the right eye, resulting in a significant improvement in visual acuity from 1/50 on the first day after surgery to 3/10 after 1 week. After 6 months, the visual acuity of the right eye was maintained at 3/20, but opacification of the lens posterior capsule was observed. Follow-up appointments are ongoing to monitor the condition of the affected eyes. Our report underscores the importance of prompt detection and management of ocular involvement in BS accompany with PFV to prevent vision loss and improve patient outcomes.ConclusionsThis report details the case of a child diagnosed with BS who accompanied a periretinal granuloma and PFV in the right eye. Regrettably, the left eye was observed to have no light perception (NLP) with the fundus not being visible. The occurrence of ocular complications in patients with BS, must be closely monitored to prevent vision loss and enhance treatment outcomes. This case underscores the importance of prompt diagnosis and management of ocular complications in patients with BS to prevent further damage and optimize patient outcomes.

Effect of curcumin on the expression of NOD2 receptor and pro-inflammatory cytokines in fibroblast-like synoviocytes (FLSs) of rheumatoid arthritis (RA) patients

BackgroundPrevious studies has shown that nucleotide-binding and oligomerization domain-containing protein 2 (NOD2) is expressed in Fibroblast-like synoviocytes (FLSs) of rheumatoid arthritis (RA) patients which is stimulated by muramyl dipeptide (MDP) present in the joint environment and induces inflammation via the NF-κB pathway. Also, other studies have shown that curcumin inhibits proliferation, migration, invasion, and Inflammation and on the other hand increases the apoptosis of RA FLSs. In this study, we aim to evaluate the effect of curcumin, a natural anti-inflammatory micronutrient, on the expression of NOD2 and inflammatory cytokines.MethodsSynovial membranes were collected from ten patients diagnosed with RA and ten individuals with traumatic injuries scheduled for knee surgery. The FLSs were isolated and treated with 40 μM curcumin alone or in combination with 20.3 μM MDP for 24 h. mRNA was extracted, and real-time PCR was performed to quantitatively measure gene expression levels of NOD2, p65, IL-6, TNF-α, and IL-1β.ResultsThe study findings indicate that administering MDP alone can significantly increase the mRNA expression levels of IL-6 and IL-1β in the trauma group and TNF-α in the RA group. Conversely, administering curcumin alone or in combination whit MDP can significantly reduce mRNA expression levels of P65 and IL-6 in FLSs of both groups. Moreover, in FLSs of RA patients, a single curcumin treatment leads to a significant reduction in NOD2 gene expression.ConclusionThis study provides preliminary in vitro evidence of the potential benefits of curcumin as a nutritional supplement for RA patients. Despite the limitations of the study being an investigation of the FLSs of RA patients, the results demonstrate that curcumin has an anti-inflammatory effect on NOD2 and NF-κB genes. These findings suggest that curcumin could be a promising approach to relieve symptoms of RA.

Tofacitinib, a suppressor of NOD2 expression, is a potential treatment for Blau syndrome.

Blau syndrome is a rare autosomal dominant autoinflammatory granulomatous disease caused by a mutation in the NOD2 gene. It is characterized by a clinical trial of granulomatous dermatitis, arthritis, and uveitis. Tofacitinib is a pan Janus kinase (JAK) inhibitor used for treatment of Blau syndrome and idiopathic sarcoidosis. Here, we evaluated its effect on inflammatory pathways associated with Blau syndrome. The effect of tofacitinib on downstream pathways regulated by mutant NOD2 was analyzed using luciferase assays with overexpression of NOD2 mutants. The effect of tofacitinib on the upstream pathway for the induction of NOD2 expression and proinflammatory cytokine production was assessed using monocytic cell lines differentiated from Blau syndrome patient-derived induced pluripotent stem cells. Tofacitinib did not suppress the increased spontaneous transcriptional activity of NF-κB by mutant NOD2. In addition, mutant NOD2 was not involved in the transcription of ISRE and GAS, which are activated by type 1 and type 2 interferons (IFN), respectively. On the other hand, IFNγ induced the expression of NOD2, which led to the production of inflammatory cytokines by an autoinflammatory mechanism only in cells with mutant NOD2. Tofacitinib suppressed the induction of NOD2 by IFNγ, thereby inhibiting the production of pro-inflammatory cytokines. Thus, tofacitinib showed anti-inflammatory effects through suppression of NOD2 expression. The JAK inhibitor tofacitinib is a potential therapeutic agent for Blau syndrome because it suppresses the autoinflammation seen in Blau syndrome by inhibiting the expression of NOD2.

Addition of β-glucans in diets for tropical gar (Atractosteus tropicus) larvae: effects on growth, digestive enzymes and gene expression of intestinal epithelial integrity and immune system.

The effect of β-glucans 1,3/1,6 from Saccharomyces cerevisiae yeast at different inclusion percentages (0.0, 0.2, 0.4, 0.6, and 0.8%) in the diet for tropical gar (Atractosteus tropicus) larvae was evaluated on growth, digestive enzyme activity and, relative expression of the immune system genes. The bioassay started on the third day after hatching (DAH) and lasted 21days, using a total of 1500 larvae of 0.055 ± 0.008g and, a total length of 2.46 ± 0.26cm. Larviculture was carried out in a recirculation system with 15 tanks of 70 L using a density of 100 organisms per experimental unit. No significant differences in larval growth were observed by the inclusion of β-glucans (p > 0.05). Digestive enzymes showed changes in lipase and trypsin activities, presenting higher values in fish fed 0.6% and 0.8% β-glucans diets compared to the other treatments (p < 0.05). Leucine-aminopeptidase, chymotrypsin, acid phosphatase, and alkaline phosphatase activity showed higher activities in larvae fed with a 0.4% β-glucan diet compared to the control group. The relative expression of intestinal membrane integrity (mucin 2) muc-2, (occludins) occ, (nucleotide-binding oligomerization domain) nod-2, and immune system lys (lysosome) genes showed over-expression in larvae fed the 0.4% β-glucan diet to the rest of the treatments (p < 0.05). The inclusion of β-glucans at 0.4-0.6% in diets for A. tropicus larvae could improve larviculture, as effects on the increase in the activity of several digestive enzymes and the expression of genes of the immune system.

Association of common inherited NOD2 mutations with exceptional response to immune checkpoint inhibitors.

2514 Background: Melanomas and lung cancers usually display a large burden of somatically mutated proteins, yet only a subset of individuals can be induced to mount a therapeutic immune response against tumours. Inherited mutations in immune regulatory genes may be one factor predisposing to a heightened immune response with addition of an immune stimulus. Methods: Germline whole genome sequencing (WGS) was performed in a patient with exceptional response (ExR) to targeted radiotherapy for metastatic melanoma (complete abscopal response). A target variant gene was identified, and interrogated within a prospectively recruited cohort of patients with ExR or non-response to anti-PD1 for non-small cell lung cancer (NSCLC). Results were experimentally tested in mice and validated in an independent mixed cancer clinical cohort. Results: Compound heterozygous variants in NOD2 were found within the patient with abscopal response (expected genotype frequency 1.3 in 10,000), whose cancer regression occurred concurrently with a flare of pre-existing Crohn’s colitis (a NOD2-associated condition). Patients treated with anti-PD1 for NSCLC were prospectively recruited (n=144). Individuals with ExR to PD1 were selected, defined by progression-free survival (PFS) ≥2 years and ≥1 CTCAE grade 2 or higher immune-related adverse event (n=40). Median follow-up was 41 months (median PFS not reached). Patients with best response of progressive disease were selected for comparison (n=18, median PFS 2.76m, 95% CI, 2.1-3.81). WGS from blood was analysed for all human NOD2 variants known to impair NOD2 signalling. Of ExR patients, 25% carried 1 or more functional NOD2 variants, totalling 11 of 80 alleles (13.8%); more than twice the expected allele frequency (6.58%, p=0.0199). Within non-responders, 1 patient carried a variant NOD2 allele (1 of 36 alleles, 2.78%). The association between NOD2 loss-of-function and heightened immune response to anti-PD1 was experimentally tested in Nod2-null C57BL/6J ( Nod2fs) mice. Nod2fs mice transplanted with a syngeneic cell line and treated with anti-PD1 showed greater tumour response compared with Nod2wild-type littermates (60-day OS 41.67% vs 0%, p&lt;0.01). Flow cytometry of tumours showed greater proportion of (CD44hi CD62Llow) CD8+ and CD4+ effector memory differentiated cells within Nod2fs versus Nod2wild-type animals (p&lt;0.05). Results were validated within an independent clinical cohort (n=105). Overall response rate to PD1 in patients with mutant vs wild-type NOD2 was 50% versus 15% (p=0.03). Conclusions: These results provide four complementary lines of evidence that common inherited defects in the immune regulatory gene NOD2 promote exceptional immune response following acute triggers to control cancer. NOD2 may be a biomarker for treatment stratification or a therapeutic target to enhance anti-PD1 response.

Quantitative Evaluation of NOD2 Promoter Methylation Profiling in Colon Biopsy Samples from Ulcerative Colitis Patients and Non-Colitis Controls

Background: Ulcerative colitis (UC) is an idiopathic chronic inflammatory disease of the colon with evidence addressing the role of epigenetic changes. The intention of this study was to detect the association of DNA methylation levels of NOD2 gene with UC and to evaluate whether any of these changes might be a useful biomarker for detecting patients with UC.&#x0D; Methods: The methylation status of the promoter CpG islands (CGIs) of NOD2 gene was examined in the colonic mucosae of 15 cancer-free patients with UC and 15 age- and sex-matched healthy controls by the real-time quantitative multiplex-methylation specific PCR (QM-MSP) assay. Methylation-specific melting curve analysis (MS-MCA) were used to analyze the data.&#x0D; Results: The median unmethylated DNA index was significantly higher in cases compared to controls, and hypormethylation of NOD2 gene was significantly correlated with UC (Unmethylated DNA in UC vs. HC; 0.102±0.055 vs. 0.025±0.016, P = 0.000).&#x0D; Conclusion: The NOD2 gene that was differentially methylated in UC patients, providing new insights into the pathogenesis of UC, with a view to making steps toward the development of accurate biomarkers for diagnostic tools in UC.

Roles of inflammasomes in viral myocarditis.

Viral myocarditis (VMC), characterized by viral infection-induced inflammation, is a life-threatening disease associated with dilated cardiomyopathy or heart failure. Innate immunity plays a crucial role in the progression of inflammation, in which inflammasomes provide a platform for the secretion of cytokines and mediate pyroptosis. Inflammasomes are rising stars gaining increasing attention. The nucleotide oligomerization domain-, leucine-rich repeat-, and pyrin domain-containing protein 3 (NLRP3) inflammasome, the caspase recruitment domain-containing protein 8 (CARD8) inflammasome, and the caspase-11 inflammasome are three inflammasomes that were reported to affect the process and prognosis of VMC. These inflammasomes can be activated by a wide range of cellular events. Accumulating evidence has suggested that inflammasomes are involved in different stages of VMC, including the trigger and progression of myocardial injury and remodeling after infection. In this review, we summarized the pathways involving inflammasomes in VMC and discussed the potential therapies targeting inflammasomes and related pathways.

Spotted sea bass (Lateolabrax maculatus) NOD2 gene involved in the immune response against Vibrio harveyi infection.

The authors declare that they have no competing interests. The data that support the findings of this study are available from the corresponding author upon reasonable request.

Fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia

ABSTRACT Dermatophytic pseudomycetoma is a rare invasive infection, involving both immunocompetent and immunocompromised individuals. Since the discovery of inherited immune disorders such as the impairment of CARD9 gene, extended dermatophyte infections are mostly ascribed to any of these host factors. This study is to present and explore the potential causes in a fatal dermatophytic pseudomycetoma patient. We present a chronic and deep pseudomycetoma caused by the common dermatophyte Microsporum canis which ultimately led to the death of the patient. Mycological examination, genetic studies and host immune responses against fungi were performed to explore the potential factors. The patient had decreased lymphocyte counts with significantly reduced CD4+ T cells, although all currently known genetic parameters proved to be normal. Through functional studies, we demonstrated that peripheral blood mononuclear cells from the patient showed severe impairment of adaptive cytokine production upon fungus-specific stimulation, whereas innate immune responses were partially defective. This is, to our knowledge, the first report of fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia, which highlights the importance of screening for immune deficiencies in patients with deep dermatophytosis.

CARD9 deficiency promotes pancreatic cancer growth by blocking dendritic cell maturation via SLC6A8-mediated creatine transport

ABSTRACT Pancreatic cancer (PC) is featured with low survival rate and poor outcomes. Herein, we found that the expression of caspase-recruitment domain-containing protein 9 (CARD9), predominantly expressed in innate immune cells, was positively related to the prognosis of PC patients. CARD9-deficient PC mice exhibited rapider cancer progression and poorer survival rate. CARD9 knockout decreased dendritic cell (DC) maturation and impaired DC ability to activate T cells in vivo and in vitro. Adoptive DC transfer confirmed that the role of CARD9 deficiency in PC relied on DCs. Creatine was identified as the most significant differential metabolite between WT DCs and CARD9−/− DCs wherein it played an essential role in maintaining DC maturation and function. CARD9 deficiency led to decreased creatine levels in DCs by inhibiting the transcription of the creatine-specific transporter, solute carrier family 6 member 8 (SLC6A8). Furtherly, CARD9 deletion blocked p65 activation by abolishing the formation of CARD9-BCL10-MALT1 complex, which prevented the binding between p65 and SLC6A8 promoter. These events decreased the creatine transport into DCs, and led to DC immaturity and impairment in antitumor immunity, consequently promoting PC progression.

Clinical features of acute generalized exanthematous pustulosis caused by hydroxychloroquine in rheumatology patients and exploration of CARD14 gene mutations.

Acute generalized exanthematous pustulosis (AGEP) is a rare condition characterized by superficial pustules following drug ingestion or infection. Currently, there is no clear link between rheumatism and AGEP. It has been described that hydroxychloroquine (HCQ) is a rare cause of acute generalized epidermal necrolysis (AGEP). Presently, there are limited studies on HCQ-induced AGEP. We aimed to explore the clinical features and associated gene expression of AGEP induced after HCQ treatment exposure in rheumatology patients. We assessed patients with HCQ-induced AGEP diagnosed at the Second Affiliated Hospital of Guizhou University of Chinese Medicine between January 1, 2017, and May 1, 2022. We also reviewed similar cases reported in specific databases. The study included five females (mean age, 40.2 years), and the mean time from initiation of HCQ treatment to symptom onset was 12.2 d. All patients received steroids and allergy medications after HCQ discontinuation, and the rash completely resolved within an average of 25.2 d. We performed whole exome sequencing and Sanger validation in our patient sample. CARD14 gene mutations were detected in three patients. Additionally, seven mutation sites were detected. HCQ-induced AGEP may have a longer latency period and regression time than AGEP induced by other drugs. Our patients all experienced CARD14 gene mutations. AGEP often resolves with topical therapy and drug discontinuation, although some cases require systemic steroid therapy. In the future, patients with rheumatism should pay attention to the effectiveness of HCQ during treatment and be aware of the associated skin toxicity.

CARD11 gain-of-function mutation drives cell-autonomous accumulation of PD-1+ ICOShigh activated T cells, T-follicular, T-regulatory and T-follicular regulatory cells.

Germline CARD11 gain-of-function (GOF) mutations cause B cell Expansion with NF-κB and T cell Anergy (BENTA) disease, whilst somatic GOF CARD11 mutations recur in diffuse large B cell lymphoma (DLBCL) and in up to 30% of the peripheral T cell lymphomas (PTCL) adult T cell leukemia/lymphoma (ATL), cutaneous T cell lymphoma (CTCL) and Sezary Syndrome. Despite their frequent acquisition by PTCL, the T cell-intrinsic effects of CARD11 GOF mutations are poorly understood. Here, we studied B and T lymphocytes in mice with a germline Nethyl-N-nitrosourea (ENU)-induced Card11M365K mutation identical to a mutation identified in DLBCL and modifying a conserved region of the CARD11 coiled-coil domain recurrently mutated in DLBCL and PTCL. Our results demonstrate that CARD11.M365K is a GOF protein that increases B and T lymphocyte activation and proliferation following antigen receptor stimulation. Germline Card11M365K mutation was insufficient alone to cause B or T-lymphoma, but increased accumulation of germinal center (GC) B cells in unimmunized and immunized mice. Card11M365K mutation caused cell-intrinsic over-accumulation of activated T cells, T regulatory (TREG), T follicular (TFH) and T follicular regulatory (TFR) cells expressing increased levels of ICOS, CTLA-4 and PD-1 checkpoint molecules. Our results reveal CARD11 as an important, cell-autonomous positive regulator of TFH, TREG and TFR cells. They highlight T cell-intrinsic effects of a GOF mutation in the CARD11 gene, which is recurrently mutated in T cell malignancies that are often aggressive and associated with variable clinical outcomes.

CARD14 Missense Variant Underlying CARD14-Associated Papulosquamous Eruption with Beneficial Response to Secukinumab

CARD14-associated papulosquamous eruption is an autosomal dominant genodermatosis characterized by early-onset, generalized erythematous patches and plaques with prominent scales, mostly with facial involvement. Heterozygous gain-of-function variants in the CARD14 gene have been reported to be causative for this entity. The pathogenesis mainly involves the IL-23‒IL-17 inflammatory circuit, yet the efficacy of anti‒IL-17 treatment remained less examined. In this study, we report one previously unidentified variant underlying the CARD14-associated papulosquamous eruption and showed its gain-of-function property. Furthermore, we present the beneficial effect of anti‒IL-17A treatment in our patient.

Commensal Bacillus siamensis LF4 induces antimicrobial peptides expression via TLRs and NLRs signaling pathways in intestinal epithelial cells of Lateolabrax maculatus

Antimicrobial peptides (AMPs) play an important role in modulating intestinal microbiota, and our previous study showed that autochthonous Baccilus siamensis LF4 could shape the intestinal microbiota of spotted seabass (Lateolabrax maculatus). In the present study, a spotted seabass intestinal epithelial cells (IECs) model was used to investigate whether autochthonous B. siamensis LF4 could modulate the expression of AMPs in IECs. And then, the IECs were treated with active, heat-inactivated LF4 and its supernatant to illustrate their AMPs inducing effects and the possible signal transduction mechanisms. The results showed that after 3 h of incubation with 108 CFU/mL B. siamensis LF4, lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), glutamic propylic transaminase (GPT) activities in supernatant decreased significantly and obtained minimum values, while supernatant alkaline phosphatase (AKP) activity, β-defensin protein level and IECs Na+/K+-ATPase activity, AMPs (β-defensin, hepcidin-1, NK-lysin, piscidin-5) genes expression increased significantly and obtained maximum values (P < 0.05). Further study demonstrated that the active, heat-inactivated LF4 and its supernatant treatments could effectively decrease the LDH, GOT, and GPT activities in IECs supernatant, increase AKP activity and β-defensin (except LF4 supernatant treatment) protein level in IECs supernatant and Na+/K+-ATPase and AMPs genes expression in IECs. Treatment with active and heat-inactivated B. siamensis LF4 resulted in significantly up-regulated the expressions of TLR1, TLR2, TLR3, TLR5, NOD1, NOD2, TIRAP, MyD88, IRAK1, IRAK4, TRAF6, TAB1, TAB2, ERK, JNK, p38, AP-1, IKKα, IKKβ and NF-κB genes. Treatment with B. siamensis LF4 supernatant also resulted in up-regulated these genes, but not the genes (ERK, JNK, p38, and AP-1) in MAPKs pathway. In summary, active, heat-inactivated and supernatant of B. siamensis LF4 can efficiently induce AMPs expression through activating the TLRs/NLRs-MyD88-dependent signaling, active and heat-inactivated LF4 activated both the downstream MAPKs and NF-κB pathways, while LF4 supernatant only activated NF-κB pathway.

Variants of NOD2 in Leishmania guyanensis-infected patients with cutaneous leishmaniasis and correlations with plasma circulating pro-inflammatory cytokines.

Leishmaniases, a group of vector-borne diseases, are caused by the protozoan intracellular parasite Leishmania (L.) and are transmitted by the phlebotomine sandflies. A wide range of clinical manifestations in L- infection is observed. The clinical outcome ranges from asymptomatic, cutaneous leishmaniasis (CL) to severe mucosal leishmaniasis (ML) or visceral leishmaniasis (VL), depending on the L. species. Interestingly, only a fraction of L.-infected individuals progress to disease development, suggesting a key role of host genetics in the clinical outcome. NOD2 plays a critical role in the control of host defense and inflammation. The NOD2-RIK2 pathway is involved in developing a Th1- type response in patients with VL and C57BL/6 mice infected with L. infantum. We investigated whether variants in the NOD2 gene (R702W rs2066844, G908R rs2066845, and L1007fsinsC rs2066847) are associated with susceptibility to CL caused by L. guyanensis (Lg) in 837 patients with Lg-Cl and 797 healthy controls (HC) with no history of leishmaniasis. Both patients and HC are from the same endemic area of the Amazonas state of Brazil. The variants R702W and G908R were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and L1007fsinsC was by direct nucleotide sequencing. The minor allele frequency (MAF) of L1007fsinsC was 0.5% among the patients with Lg-CL and 0.6% in the healthy controls group. R702W genotypes frequencies were similar in both groups. Only 1% and 1.6% were heterozygous for G908R among the patients with Lg-CL and HC, respectively. None of the variants revealed any association with susceptibility to the development of Lg-CL. Correlations of genotypes with the level of plasma cytokines revealed that individuals with the mutant alleles of R702W tend to have low levels of IFN-γ. G908R heterozygotes also tend to have low IFN-γ, TNF-α, IL-17, and IL-8. Variants of NOD2 are not involved in the pathogenesis of Lg-CL.

Manifestations of B-cell expansion with NF-κB and T-cell anergy disease overlapping with hemophagocytic lymphohistiocytosis.

B cell expansion with NF-κB and T cell anergy (BENTA) is a disease genetically linked with heterozygous gain-of-function (GOF) mutations in the CARD11 gene with an autosomal dominant expression. Hemophagocytic lymphohistiocytosis (HLH) is a heterogeneous group of disorders characterized by systemic inflammation and hypercytokinaemia. Some BENTA patients share similar clinical manifestations as HLH in various aspects, including feverand splenomegaly. In this study, we reported a 15-month-old boy diagnosed as BENTA meeting with diagnostic criteria of HLH. The complications were resolved by antibiotics for controlling severe infection, together with the reduced format of dexamethasone and etoposide for subsiding HLH activities. While the patient was not subjected to disease recurrence and maintained free of infection, a persistent lymphocytosis derived mainly from the expansion of polyclonal B cells was ascertained. Flow cytometry analysis indicated that the subdued degranulation of NK cells prior to treatment had been restored as the HLH-related complications waned. With largely reduced number and ratios in CD4 and CD8 T cells, their proliferation and Vβ diversity remained in normal ranges. In vitro stimulation experiment revealed a functional abbreviation of T cells as the percentage of IFNγ-releasing CD3+CD4+ T cells augmented while the percentage reduced in CD3+CD4- T cells. Whole exome sequencing revealed a de novo G123D missense mutation in the CARD11 gene. This new case of BENTA showcased a scenario of predominant HLH activities accompanied by a severe infection normally associated with BENTA. In addition, a brief treatment quenching HLH complication in cooperation with antibiotics for infection control was not able to solve the underlined T cell abnormality as well as B cell expansion caused by CARD11 mutation. A haematopoietic stem cell transplantation or gene therapy is still a pursuit to remedy this inborn error of immunity.