Nucleotide-binding Oligomerization Domain 2 Gene Research Articles

Two variants of NOD2 gene polymorphisms and their relation with Tuberculosis in Andhra Pradesh population, India

IntroductionTuberculosis (TB) remains one of the major infectious diseases even after the emergence of new diseases in the present era. Few polymorphic gene studies on Nucleotide-binding Oligomerization Domain 2 (NOD2) gene reveal that they are associated with the risk of TB in some populations. An attempt has been made to find such association in the Andhra Population of India. MethodsTwo variants (rs2066847 and rs2066842) of NOD2 gene were analyzed genotypically using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR–RFLP) analysis, on TB patients and negative controls. Statistical tests like Chi-square, Odds ratio (OR) and 95 % Confidence Interval (CI) were considered to evaluate the susceptibility of the NOD2 gene polymorphism with TB. ResultsThe analysis of the results obtained revealed that the two variants of NOD2 gene rs2066842 (OR = 1.278; 95%CI = 0.436–3.746; P = 0.653), and rs2066847 (OR = 0.809; 95%CI = 0.015–41.227; P = 0.915) do not attribute to the risk of TB in this population. ConclusionThe final results of the study reveal that these two polymorphisms of the NOD2 gene do not show an association with the susceptibility of TB in the Andhra Population of India. Further studies in different ethnic groups with larger sample sizes are necessary to evaluate the proper associative gene expression of NOD2 with TB.

No role of common NOD2 gene variants in predicting sepsis related outcomes in Indian patients undergoing hematopoietic stem cell transplant

BackgroundHigh-risk single nucleotide polymorphisms (SNPs) in nucleotide-binding oligomerization domain-2 (NOD2) gene are associated with high susceptibility for infections and inflammation due to risk of inappropriate cytokine production and NF-κB activation. We studied the incidence of three high-risk NOD2 gene SNPs (8, 12 and 13) among BM-transplant (BMT) recipients. MethodsSequential patients undergoing BMT over 1-year period were prospectively studied. Patients were tested with MspI/HhaI or NlaIV restriction-endonucleases (Euryx, Gdansk, Poland) for NOD2 gene SNPs 8, 12, and 13, respectively. Regimen-related organ toxicity was graded using the Seattle-Bearman criteria. ResultsForty patients were enrolled, their median age was 38 years (range 3–64), and 52.5% were males. Twenty patients each (50%) underwent autologous and allogeneic BMT. Majority of the patients (n = 38, 95%) developed febrile-neutropenia in the post-transplant period and 4 patients died due to overwhelming sepsis within day +100. Acute graft-versus-host disease (GVHD) [grade I–II (n = 3) and grade III-IV (n = 6)] was observed in 9/20 allogeneic HSCT recipients. None of our 40 patients showed presence of any of the three NOD2 gene SNPs. ConclusionThe 3 commonly observed high risk SNPs (8,12, and 13) of NOD2 genes were not present in study population. It is quite likely that due to geographical and racial variations these polymorphisms are completely absent in North India. NOD2 gene is highly diverse and polymorphic variants can be absolutely different in various populations. Larger studies targeting sequencing of the whole NOD2 gene can convincingly rule out or confirm the role of NOD2 gene variants in Indian population.

Clinical characteristics of patients with NOD2 high risk allele variants

The nucleotide-binding oligomerization domain 2 (NOD2) is an intracellular pattern recognition receptor. NOD2 gene variants are associated with inflammatory bowel disease (IBD) as well as Blau and Yao syndromes. IBD is associated with extraintestinal manifestations, including autoinflammation, which may be the presenting symptoms. The clinical symptoms may depend on the specific gene variants. This retrospective study was undertaken to examine the clinical manifestations of patients with pathogenic NOD2 variants in our institution. This study was approved by our Institutional Review Board.From January 2020 to February 2022, we identified 203 patients that had genetic testing that included the NOD2 gene. Forty-one had high risk alleles variants (HRA) that segregated in three mutations: HRA1 c.2104C>T (n = 24); HRA2 c.3019dup (n = 11); and HRA3 c.2722G > C (n = 6).The reported age of initial symptoms ranged from 21 days to 62 years, with most patients being < 12 years of age. All three variants had clinical evidence of immune dysregulation. Common manifestations (listed respectively for the three variants) included asthma (HRA1 = 21%, HRA2 = 9%, HRA3 = 33%), reflux/gastritis (29%, 18%, 33%), irritable bowel syndrome (21%, 18%, 7%), chronic diarrhea (8%, 18%, 0%), IBD (13%, 27%, 50%), recurrent fevers (38%, 45%, 0%), cytokine storm (4%, 9%, 17%), arthralgia/arthritis (33%, 45%, 17%), skin rashes (42%, 36%, 0%), malignancy (13%, 0%, 17%), bacterial infections (38%, 36%, 67%), fungal infections (4%, 18%, 0%), other autoimmune (21%, 9%, 0%), autoinflammatory syndromes (13%, 45%, 0%). Autoinflammatory/autoimmune disorders diagnosed within the cohort included PFAPA (HRA1 = 0, HRA2 = 1, HRA3 = 0), Yao syndrome (1, 0, 0), juvenile idiopathic arthritis (1, 1, 0), SAPHO syndrome (0, 1, 0), relapsing polychondritis (0,1,0), lupus (0,1,0), Sjogren’s syndrome (0,1,0), Raynaud’s syndrome (1, 0, 0), vitiligo (0, 1, 0), type I diabetes (2, 0, 0) and hypothyroidism (2, 1, 0). Detailed information is in table 1.Our chart review demonstrates a broad spectrum of extraintestinal clinical manifestations of patients with NOD2 variants which do not always include IBD. NOD2 is important in the protection of infection and autoinflammation and its role in human disease needs to be examined further.

Evaluation of serum levels of interferon beta (INF-B) and Nucleotide-binding oligomerization domain 2 (NOD2) gene polymorphism in children with atopic asthma phenotype

Background People of all ages are primarily affected by the chronic inflammatory disease asthma, which is most common in children. A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire found 7.7% of Nile Delta schoolchildren had asthma. This research was to show is their association between the underlying gene polymorphisms of NOD2 and serum level of INF beta and atopic asthma phenotype in Egyptian children and evaluate is their relationship between NOD2 gene polymorphism and the serum level of INF beta. Methods The 127 asthmatic children in this case-control study had typical asthma symptoms, and the 39 age- and sex-matched healthy controls. Subjects were divided in to three groups: Atopic asthma phenotype group: included 60 asthmatic children who had allergic rhinitis and atopic dermatitis as a predominant symptom, Wheezy phenotype group: included 67 asthmatic children presented predominantly with wheezes and controls: 39 healthy controls were chosen because they appeared to be in good health, had no history of symptoms similar to those of asthma, and had no relatives who had allergies or asthma. Results Total serum IgE and eosinophil percentage in control groups showed a positive correlation (r=0.640, P=0.006). In asthmatics, serum INF-β and IgE correlated positively (r=0.217, P=0.031). Increased Serum eosinophilic percentage was associated with decreased serum INF-β and increased serum IgE. Conclusions In comparison to the wheezy phenotype group, the percentage of eosinophils is significantly higher in the atopic asthma phenotype. Serum INF-β and IgE levels went up in tandem with the percentage of eosinophils in the blood. rs2066845 NOD2 genotype The GG genotype increased the risk of asthma in general but not the type of asthma.

Association of the rs2111234, rs3135499, rs8057341 polymorphisms in the NOD2 gene with leprosy: A case-control study in the Norte de Santander, Colombia population.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. The development of leprosy involves several factors, including the causative agent, the individual host's immune response, environmental factors, and the genetic background of the host. Specifically, the host's innate immune response, encoded by genes, determines their susceptibility to developing leprosy post-infection. Polymorphic variants in the nucleotide-binding oligomerization domain 2 (NOD2) gene are associated with leprosy among populations in a variety of endemic areas around the world. Colombia, a country located in the tropical zone, has several leprosy-endemic regions, including Norte de Santander. The aim of this study was to analyze the rs7194886, rs2111234, rs3135499, and rs8057341 single nucleotide polymorphisms (SNPs) in the NOD2 gene using a case-control study to determine whether they confer greater or lesser susceptibility to the development of leprosy. The TaqMan qPCR amplification system was used for SNPs detection. An association between the A-rs8057341 SNP (p = 0,006286) and resistance to leprosy was found. However, the rs3135499 (p = 0,9063) and rs2111234 (p = 0.1492) were not found to be associated with leprosy susceptibility. In addition, the rs7194886 SNP was not found to be in Hardy-Weinberg equilibrium (HWE) in the study population. The GAG haplotype, consisting of SNPs rs2111234-G, rs3135499-A, and rs8057341G, acts as a susceptibility factor for the development of leprosy in women. SNPs rs3135499 and rs8057341 are functionally related to decreased NOD2 expression according to an in-silico analysis. The SNPs rs8057341-A was related with resistance to leprosy and the haplotype rs2111234-G, rs3135499-A and rs8057341-G SNPs was related with susceptibility in the Norte de Santander Colombia, studied population.

Association of polymorphous light eruption with NOD-2 and TLR-5 gene polymorphisms.

Polymorphous light eruption (PLE) is a common, immunologically mediated, photosensitive skin disease. After ultraviolet-B (UV-B) irradiation, patients with PLE show reduced Langerhans cell (LC) depletion in the epidermis, which results in a non-suppressive microenvironment in the skin. Interestingly, severe acute graft-versus-host disease (aGvHD) occurred in stem cell transplanted patients that showed no or incomplete depletion of LCs after UVB irradiation. Genetic variation in nucleotide-binding oligomerization domain 2 (NOD-2) and toll-like receptor 5 (TLR-5) genes also confers susceptibility to aGvHD. We hypothesized that PLE is associated with genetic variation in the NOD-2 and TLR-5 genes. We investigated single-nucleotid polymorphisms (SNPs) of NOD-2 (R702W, G908R, 3020Cins) and TLR-5 (A592S, P616L, N392STOP) in skin biopsies of patients with PLE (n = 143) and in healthy controls (n = 104) using restriction fragment length polymorphism analysis. The frequency of NOD-2 alleles with the SNP R702W was significantly higher in PLE than in controls (31.8% vs. 6.3%; P < 0.0001), and homozygous carriers of this mutation were more common in PLE (27.9% vs. 0%; P < 0.0001). For SNP 3020Cins, the allele frequency (7.3% vs. 0.7%; P = 0.0025) and the number of heterozygotes (14.7% vs. 1.3%; P = 0.0019) were higher in PLE. The frequency of alleles with the N392STOP SNP of the TLR5 gene, which is associated with a truncated, non-functional receptor, was significantly higher in PLE (21% vs. 5%; 7% vs. 1% homozygotes, 28% vs. 8% heterozygotes; P < 0.0001). The other SNPs did not differ significantly. This study yielded a high frequency of functional SNPs in the NOD-2 and TLR-5 genes in PLE. The same SNPs are associated with aGvHD and there are similarities in the reaction of LCs after UVB irradiation between aGvHD and PLE. This leads to the hypothesis that patients with PLE may be more susceptible to developing GvHD after stem cell transplantation, an assumption that needs to be investigated further.

Association between NOD2 gene polymorphisms and susceptibility to pulmonary tuberculosis in Zahedan, Southeast Iran

IntroductionTuberculosis (TB) in human societies is believed to be a major health menace and is considered as an important cause of morbidity and mortality worldwide. Nucleotide-binding oligomerization domain 2 (NOD2) is one of the pathogen recognition receptors (PRRs) that play its function in account of the recognition of peptidoglycans in bacterial cell wall. NOD2 gene polymorphisms could influence the levels of gene expression and may attribute to infections. MethodsThe present case-control study was conducted on 152 patients with pulmonary tuberculosis (PTB) and 162 healthy subjects to determine whether the NOD2 polymorphisms (rs2066842 and rs2066847) are associated with PTB. These polymorphisms were determined utilizing PCR-restriction fragment length polymorphism (PCR-RFLP). ResultsThe obtained results indicated that the NOD2 rs2066842 polymorphism under dominant/recessive model were associated with the increased susceptibility to PTB (P < 0.0001; OR = 2.988). No significant differences were found among the groups regarding rs2066847 polymorphism. ConclusionWe noticed that the NOD2 rs2066842 polymorphism but not rs2066847 polymorphism, provide a relative susceptibility factor for PTB patients in an Iranian population sample.

Association of rs3135500 and rs3135499 Polymorphisms in the MicroRNAbinding Site of Nucleotide-binding Oligomerization Domain 2 (NOD2) Gene with Susceptibility to Rheumatoid Arthritis

The nucleotide-binding oligomerization domain 2 (NOD2) is the key regulator of inflammatory responses and has been involved in the pathogenesis of rheumatoid arthritis (RA). Laboratory and in silico evaluations have demonstrated that some polymorphisms in 3ˊUTR of NOD2 gene could influence the secondary structure of this region and similarly thermodynamic features of hybridization site and finally deregulate the expression of NOD2. In the current study, for the first time, we evaluated the possible association between single nucleotide polymorphisms (SNPs) rs3135500 and rs3135499 in the NOD2 gene with RA risk in the Iranian population. One hundred and fifteen patients with RA and 120 healthy subjects were recruited in this case-control study. Genotyping of rs3135500 and rs3135499 polymorphisms were accomplished using the real‑time polymerase chain reaction high resolution melting (HRM) method. We found a substantial association of AA and AG genotypes in rs3135500 with the risk of RA (AA vs GG; OR=5.547; 95%CI [2.564-11.999]; p&lt;0.001 and AG vs GG; OR=2.179; 95%CI [1.145-4.147]; p=0.017). Moreover, in the patient group, there was a significant relationship between the increased concentration of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) with rs3135500 (A allele) (p&lt;0.05). However, there were no important associations between rs3135499 with the risk of RA (p&gt;0.05). However, we found a noteworthy association of the C allele in rs3135499 with an increased level of CRP in patients (p&gt;0.05). Our findings propose a considerable association between NOD2 polymorphisms with increased risk of RA and disease activity.

The association of nucleotide-binding oligomerization domain 2 gene polymorphisms with the risk of asthma in the Chinese Han population.

BackgroundGenetic background is one of the important risk factors for development of asthma. The nucleotide‐binding oligomerization domain 2 (NOD2) has been involved in the pathogenesis of asthma. The purpose of this study was to explore the relationship between NOD2 gene polymorphisms and asthma susceptibility in the Chinese Han population.MethodsChildren with asthma (n = 309) and Healthy children (n = 163) were recruited from Yancheng Third People's Hospital, Yancheng, China, between January 2016 and December 2017. The NOD2 gene polymorphisms were measured by the Snapshot SNP genotyping assays. Genotyping was performed for 4 tag SNPs of NOD2. Serum IFN‐β levels were measured by ELISA.ResultsThe serum IFN‐β levels were significantly lower in Asthmatic children than those in the controls (p < 0.001). Low levels of IFN‐β may be related to the susceptibility to severe asthma. The rs3135499 C allele was associated with a significantly increased risk of asthma as compared with the rs3135499 A allele.ConclusionThe rs3135499 polymorphism of NOD2 gene and IFN‐β may play a role in the pathogenesis of asthma.

Biomarkers of intestinal fibrosis - one step towards clinical trials for stricturing inflammatory bowel disease.

Intestinal fibrosis, caused by an excessive deposition of extracellular matrix components, and subsequent stricture development are a common complication of inflammatory bowel disease. However, currently there are no biomarkers which reliably predict the risk of developing intestinal strictures or identify early stages of fibrosis prior to clinical symptoms. Candidate biomarkers of intestinal fibrosis, including gene variants (i.e. nucleotide-binding oligomerization domain-2 gene), serum microRNAs (miR-19, miR-29), serum extracellular matrix proteins (i.e. collagen, fibronectin) or enzymes (i.e. tissue inhibitor of matrix metalloproteinase-1), serum growth factors (i.e. basic fibroblast growth factor, YKL-40), serum anti-microbial antibodies (i.e. anti-Saccharomyces cerevisiae) and circulating cells (i.e. fibrocytes) have shown conflicting results on relatively heterogeneous patients' cohorts, and none of them was proven to be strictly specific for fibrostenosis, but rather predictive of a disease disabling course. In this review we critically reassess the diagnostic and prognostic value of serum biomarkers of intestinal fibrosis in inflammatory bowel disease.

Polymorphisms of nucleotide-binding oligomerization domain 2 (NOD2) gene in miniature dachshunds with inflammatory colorectal polyps

Inflammatory colorectal polyps (ICRPs) frequently occur in miniature dachshunds (MDs) in Japan, typically form multiple polyps with severe neutrophil infiltration. ICRPs are speculated as a novel, breed-specific canine inflammatory bowel disease. Pattern recognition receptors (PRRs) play an important role in the differentiation of pathogens from commensal bacteria and food antigens, and polymorphisms of various PRRs have been shown to be associated with human and canine IBD. We recently reported that the reactivity of nucleotide-binding oligomerization domain 2 (NOD2), toll-like receptor (TLR) 1/2, TLR2, and TLR2/6 are greater in ICRP-affected MDs than that in controls. Therefore, this study was aimed to investigate single nucleotide polymorphisms (SNPs) of PRRs associated with ICRPs in MDs. Mutational analysis of canine NOD2, TLR1, TLR2, and TLR6 genes was performed with six ICRP-affected MDs, five control MDs, and five healthy beagles. The mutational analysis identified 13 non-synonymous SNPs in NOD2, TLR1, TLR2, and TLR6 genes, of which six SNPs in NOD2 exon 3 were further analyzed in an association study using 63 ICRP-affected MDs, 82 control MDs, and 237 control dogs of various breeds. Four of the SNPs (A1532G, T1573C, C1688G, and G1880A of the NOD2 gene) were in Hardy–Weinberg equilibrium and in complete linkage disequilibrium in MDs, and their minor allele frequencies were significantly lower in ICRP-affected MDs than in control MDs (0.016 vs. 0.140, P=0.0002). The calculated inheritance model was an additive model (odds ratio=0.10, 95% confidence interval=0.02–0.45, P=0.0001), which indicates that the haplotype with minor alleles in these SNPs (A, T, C, and G in A1532G, T1573C, C1688G, and G1880A) possess a protective effect regarding the development of ICRPs. However, these SNPs were not specific for MDs, although the minor allele frequencies of these SNPs in control MDs were significantly lower than in other breed dogs. These results suggest that the identified four SNPs (A1532G, T1573C, C1688G, and G1880A in the NOD2 gene) may play a role in the pathogenesis of ICRPs in MDs. Because the majority of MDs and other breed dogs do not have the protective alleles, their absence may not be a specific cause of ICRPs in MDs but rather contribute to the development of inflammation.

Differential effect of vitamin D on NOD2- and TLR-induced cytokines in Crohn's disease.

Accumulating evidence implicates defective innate immunity in the pathogenesis of Crohn's disease (CD). Ineffectual NOD2 (nucleotide-binding oligomerization domain 2) is the most common susceptibility gene contributing to CD. Vitamin D (vD), a potent modulator of innate and adaptive immunity, induces NOD2 gene expression and its downstream function. We hypothesized that the hormonal form of vD (1,25D) could beneficially modulate innate immune function in CD. Using peripheral mononuclear cells and monocyte-derived dendritic cells (Mo-DCs) from CD, it was found that 1,25D decreased Toll-like receptor (TLR)-induced cytokine production and enhanced cytokine levels induced by muramyl dipeptide (MDP), the NOD2 ligand. 1,25D increased the synergistic effect provided by NOD2 and TLR co-activation on interleukin (IL)-10, IL-23, and tumor necrosis factor-alpha (TNF-α). Whereas 1,25D inhibits Mo-DC TLR-induced cytokines, co-stimulation of NOD2 results in increased IL-10 and IL-23. IL-12p70 was completely abrogated by 1,25D. 1,25D similarly modulated cytokine production by immune cells in ulcerative colitis patients and healthy controls. Mo-DCs from CD patients heterozygous for NOD2 mutations had a response similar to those from patients without NOD2 mutations. Immune cells from patients homozygous for the 1007 fs mutation were unresponsive to MDP and 1,25D. Our in vitro data support 1,25D as a potential modulator of immunity. However, these results cannot be extrapolated to CD patients without further controlled studies.

Dermatitis as a characteristic phenotype of a new autoinflammatory disease associated with NOD2 mutations

We sought to characterize a new category of autoinflammatory disease associated with nucleotide-binding oligomerization domain 2 (NOD2) gene mutations. A total of 22 patients were identified, inclusive of those reported previously. All had autoinflammatory phenotypes and NOD2 gene mutations that were prospectively studied between January 2009 and February 2012. All 22 patients were non-Jewish whites (13 women and 9 men). The mean age at diagnosis was 40.1 years (range 17-72), with a mean disease duration of 4.7 years (range 1-13). Three female patients were siblings. Common clinical features were weight loss (13/22), episodic self-limiting fever (13/22), dermatitis (19/22), and inflammatory polyarthritis/polyarthralgia (20/22). Gastrointestinal symptoms occurred in 13 patients, sicca-like symptoms in 9, and recurrent chest pain in 5. All patients carried the NOD2 gene mutations, with the intervening sequence 8(+158) variant in 21 and the R702W variant in 8. The NOD2 allelic frequency may need to be examined in a larger population with systemic autoimmune diseases. The characteristic clinical phenotype, notably dermatitis, coupled with certain NOD2 variants constitutes a new autoinflammatory disease entity, which we have named as NOD2-associated autoinflammatory disease.

Effects of muramyl dipeptide on the differentiation of human dental pulp cells

To investigate the nucleotide-binding oligomerization domain-2 (NOD-2) gene expression in deep caries and the effects of NOD-2 agonist muramyl dipeptide (MDP) on the differentiation of human dental pulp cells (hDPC). NOD-2 gene level in deep caries and healthy pulp tissue was determined by real-time quantitative polymerase chain reaction (realtime-PCR). Realtime-PCR, Western blotting and immunofluorescence were performed to evaluate NOD-2 gene and protein expression. Dentin sialoprotein (DSP) protein level was assessed when hDPC were challenged by different concentrations of MDP for 24 hours, and sialophosphoprotein (DSPP), osteocalcin (OCN) mRNA and osteopontin (OPN) protein level were detected at different time points after incubation with 0.1 mg/L MDP. NOD-2 mRNA level was higher in pulp tissue of deep caries (0.2610 ± 0.0824) than that in healthy controls (0.0024 ± 0.0002), P < 0.05. The expression of NOD-2 gene and protein increased in a time denpendent manner upon stimulation with MDP. Immunofluorescence confirmed that NOD-2 protein was located in cytoplasm. Moreover, 0.1 mg/L MDP augmented DSP protein level. DSPP and OCN mRNA were elevated with time and reached the peak at 12 h and down-regulated. OPN protein level also increased with time. Dental pulp NOD-2 expression are up-regulated in pulp tissue of deep caries. MDP may be related to the differentiation of hDPC.

Organic dust augments nucleotide-binding oligomerization domain expression via an NF-κB pathway to negatively regulate inflammatory responses

Nucleotide-binding oligomerization domain 2 (NOD2) is involved in innate immune responses to peptidoglycan degradation products. Peptidoglycans are important mediators of organic dust-induced airway diseases in exposed agriculture workers; however, the role of NOD2 in response to complex organic dust is unknown. Monocytes/macrophages were exposed to swine facility organic dust extract (ODE), whereupon NOD2 expression was evaluated by real-time PCR and Western blot. ODE induced significant NOD2 mRNA and protein expression at 24 and 48 h, respectively, which was mediated via a NF-κB signaling pathway as opposed to a TNF-α autocrine/paracrine mechanism. Specifically, NF-κB translocation increased rapidly following ODE stimulation as demonstrated by EMSA, and inhibition of the NF-κB pathway significantly reduced ODE-induced NOD2 expression. However, there was no significant reduction in ODE-induced NOD2 gene expression when TNF-α was inhibited or absent. Next, it was determined whether NOD2 regulated ODE-induced inflammatory cytokine production. Knockdown of NOD2 expression by small interfering RNA resulted in increased CXCL8 and IL-6, but not TNF-α production in response to ODE. Similarly, primary lung macrophages from NOD2 knockout mice demonstrated increased IL-6, CXCL1, and CXCL1, but not TNF-α, expression. Lastly, a higher degree of airway inflammation occurred in the absence of NOD2 following acute (single) and repetitive (3 wk) ODE exposure in an established in vivo murine model. In summary, ODE-induced NOD2 expression is directly dependent on NF-κB signaling, and NOD2 is a negative regulator of complex, organic dust-induced inflammatory cytokine/chemokine production in mononuclear phagocytes.

Genetic association between bovine NOD2 polymorphisms and infection by Mycobacterium avium subsp. paratuberculosis in Holstein‐Friesian cattle

Nucleotide-Binding Oligomerization Domain 2 (NOD2) has been reported to be a candidate gene for Mycobacterium avium subsp. paratuberculosis (MAP) infection in a Bos taurus × Bos indicus mixed breed based on a genetic association with the c.2197T>C single nucleotide polymorphism (SNP). Nevertheless, this SNP has also been reported to be monomorphic in the B. taurus species. In the present work, 18 SNPs spanning the bovine NOD2 gene have been analysed in a genetic association study of two independent populations of Holstein-Friesian cattle. We found that the C allele of SNP c.*1908C>T, located in the 3′-UTR region of the gene, is significantly more frequent in infected animals than in healthy ones, which supports the idea that the bovine NOD2 gene plays a role in susceptibility to MAP infection. However, in silico analyses of the NOD2 nucleotide sequence did not yield definitive data about a possible direct effect of SNP c.*1908C>T on susceptibility to infection and led us to consider its linkage disequilibrium with the causative variant. A more exhaustive genetic association study including all putative, functional SNPs from this gene and subsequent functional analyses needs to be conducted to achieve a more complete understanding of how different variants of NOD2 may affect susceptibility to MAP infection in cattle.

Sporadic Blau Syndrome With Onset of Widespread Granulomatous Dermatitis in the Newborn Period

Blau syndrome is a dominantly inherited, chronic autoinflammatory disorder characterized by the clinical triad of granulomatous dermatitis, symmetric arthritis, and recurrent uveitis with onset below 4 years of age. It is caused by activating mutations in the nucleotide-binding oligomerization domain 2 (NOD2) gene, previously referred to as CARD15 gene. Noncaseating granulomas in affected tissues are the pathologic hallmark of the condition. We report the lifelong severe disease course in a 14-year-old Caucasian boy with sporadic Blau syndrome. Unusually, granulomatous dermatitis started in the first week of life. Whereas skin involvement faded away spontaneously in subsequent years, polyarthritis and anterior uveitis appeared in the second and third year of life respectively. Mutational analysis of the NOD2 gene revealed a missense mutation (R334W) previously detected in other Blau syndrome pedigrees. With this report, we would like to stress the rare possibility of Blau syndrome in generalized papular rashes of infancy and the importance of histopathologic study for clarification. The finding of early-onset widespread granulomatous dermatitis should prompt eye and joint examination in regular intervals and entail mutational analysis of the NOD2 gene.

Maternal TLR4 and NOD2 Gene Variants, Pro-Inflammatory Phenotype and Susceptibility to Early-Onset Preeclampsia and HELLP Syndrome

BackgroundAltered maternal inflammatory responses play a role in the development of preeclampsia and the hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome. We examined whether allelic variants of the innate immune receptors Toll-like receptor 4 (TLR4) and nucleotide-binding oligomerization domain 2 (NOD2), that impair the inflammatory response to endotoxin, are related to preeclampsia and HELLP syndrome.Methods and FindingsWe determined five common mutations in TLR4 (D299G and T399I) and NOD2 (R702W, G908R and L1007fs) in 340 primiparous women with a history of early-onset preeclampsia, of whom 177 women developed HELLP syndrome and in 113 women with a history of only uneventful pregnancies as controls. In addition, we assessed plasma levels of pro-inflammatory biomarkers C-reactive protein, interleukin-6, soluble intercellular adhesion molecule-1, fibrinogen and von Willebrand factor in a subset of 214 women included at least six months after delivery. After adjustment for maternal age and chronic hypertension, attenuating allelic variants of TLR4 were more common in women with a history of early-onset preeclampsia than in controls (OR 2.9 [95% CI 1.2–6.7]). Highest frequencies for TLR4 variants were observed in women who developed HELLP syndrome (adjusted OR 4.1 [95% CI 1.7–9.8]). In addition, high levels of interleukin-6 and fibrinogen were associated with a history of early-onset preeclampsia. Combined positivity for any of the TLR4 and NOD2 allelic variants and high levels of interleukin-6 was 6.9-fold more common in women with a history of early-onset preeclampsia (95% CI 2.1–23.2) compared to controls.ConclusionsWe observed an association of common TLR4 and NOD2 gene variants, and pro-inflammatory phenotype with a history of early-onset preeclampsia and HELLP syndrome. These findings suggest involvement of the maternal innate immune system in severe hypertensive disorders of pregnancy.

Widespread Granulomatous Dermatitis of Infancy

Pediatric sarcoidosis has traditionally been divided into 2 distinct groups: (1) school-aged children and adolescents with frequent involvement of the lungs and mediastinal lymph nodes (similar to adult sarcoidosis) and (2) infants and preschoolers with the triad of arthritis, uveitis, and a cutaneous eruption of discrete small papules, referred to as early-onset sarcoidosis. Blau syndrome, a rare autosomal dominant genodermatosis caused by mutations in the NOD2 (nucleotide-binding oligomerization domain 2) gene, has been considered as the familial form of early-onset sarcoidosis. A 9-month-old boy developed an asymptomatic eruption of 1- to 2-mm, red-brown to pinkish tan, flat-topped papules on the face, trunk, and extremities. There was no evidence of ocular involvement or arthritis. The skin lesions were characterized histologically by noncaseating granulomas in a periadnexal distribution within the dermis. A family history of uveitis supported a diagnosis of Blau syndrome, and analysis of the NOD2 gene revealed a heterozygous gain-of-function missense mutation (Arg334Trp) that has previously been detected in Blau syndrome kindreds. We draw attention to granulomatous dermatitis as an early manifestation of Blau syndrome and highlight emerging molecular evidence that this heritable autoinflammatory disorder and early-onset sarcoidosis represent a single disease entity.

Heterozygous nucleotide-binding oligomerization domain-2 mutations affect monocyte maturation in Crohn’s disease

To investigate the function of monocytes in Crohn's disease (CD) patients and to correlate this with disease-associated nucleotide-binding oligomerization domain-2 (NOD2) gene variants. Monocytes from 47 consecutively referred CD patients and 9 healthy blood donors were cultured with interleukin (IL)-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF), and stimulated with lipopolysaccharide (LPS) or muramyldipeptide (MDP), the putative ligand of NOD2. We found that monocytes from CD patients differentiated in vitro to mature dendritic cells (DCs), as determined by immunophenotype and morphology. NOD2 genotype was assessed in all subjects, and we observed high CD86 expression on immature and LPS-stimulated DCs in NOD2 mutated CD patients, as compared with wtNOD2 CD patients and controls. By contrast, CD86 expression levels of DCs induced to maturity with MDP derived from NOD2-mutated subjects were comparable to those of normal subjects. The amount of IL-12p70 in patient-cell cultures was larger than in controls after LPS treatment, but not after treatment with MDP. Our results suggest that DCs obtained from patients with mutations in the NOD2 gene display an activated phenotype characterized by high CD86 expression, but have a diminished response to MDP when compared to the terminal differentiation phase. We speculate that the altered differentiation of monocytes might lead to an imbalance between inflammation and the killing ability of monocytes, and may be relevant to the pathogenesis of CD.