1
|
Bethell GS, Hall NJ. Recent advances in our understanding of NEC diagnosis, prognosis and surgical approach. Front Pediatr 2023; 11:1229850. [PMID: 37583622 PMCID: PMC10424793 DOI: 10.3389/fped.2023.1229850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 07/21/2023] [Indexed: 08/17/2023] Open
Abstract
Necrotising enterocolitis (NEC) remains a devasting condition that has seen limited improvement in outcomes in recent years. The incidence of the disease is increasing as more extremely premature infants survive. NEC is responsible for 1 in 10 neonatal deaths and up to 61% of survivors have significant neurodevelopmental delay. The aim of this review is to highlight recent advances in diagnosis, prognosis and surgical approach in this condition. Many recent studies have reported novel methods of diagnosis of NEC with the aim of earlier and more accurate identification. These include imaging and machine learning techniques. Prognostication of NEC is particularly important to allow earlier escalation of therapy. Around 25% of infants with NEC will require surgery and recent data has shown that time from disease onset to surgery is greater in infants whose indication for surgery is failed medical management, rather than pneumoperitoneum. This indication was also associated with worse outcomes compared to pneumoperitoneum. Ongoing research has highlighted several new methods of disease prognostication which includes differentiating surgical from medical NEC. Finally, recent randomised controlled trials in surgical technique are discussed along with the implications of these for practice. Further, high quality research utilising multi-centre collaborations and high fidelity data from electronic patient records is needed to address the issues discussed and ultimately improve outcomes in NEC.
Collapse
Affiliation(s)
- George S Bethell
- University Surgical Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Nigel J Hall
- University Surgical Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| |
Collapse
|
2
|
Bautista GM, Cera AJ, Chaaban H, McElroy SJ. State-of-the-art review and update of in vivo models of necrotizing enterocolitis. Front Pediatr 2023; 11:1161342. [PMID: 37082706 PMCID: PMC10112335 DOI: 10.3389/fped.2023.1161342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 03/13/2023] [Indexed: 04/22/2023] Open
Abstract
NEC remains one of the most common causes of mortality and morbidity in preterm infants. Animal models of necrotizing enterocolitis (NEC) have been crucial in improving our understanding of this devastating disease and identifying biochemical pathways with therapeutic potential. The pathogenesis of NEC remains incompletely understood, with no specific entity that unifies all infants that develop NEC. Therefore, investigators rely on animal models to manipulate variables and provide a means to test interventions, making them valuable tools to enhance our understanding and prevent and treat NEC. The advancements in molecular analytic tools, genetic manipulation, and imaging modalities and the emergence of scientific collaborations have given rise to unique perspectives and disease correlates, creating novel pathways of investigation. A critical review and understanding of the current phenotypic considerations of the highly relevant animal models of NEC are crucial to developing novel therapeutic and preventative strategies for NEC.
Collapse
Affiliation(s)
- Geoanna M. Bautista
- Department of Pediatrics, Division of Neonatology, University of California, Davis, Sacramento, CA, United States
| | - Anjali J. Cera
- Department of Pediatrics, Division of Neonatology, University of California, Davis, Sacramento, CA, United States
| | - Hala Chaaban
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma, OK, United States
| | - Steven J. McElroy
- Department of Pediatrics, Division of Neonatology, University of California, Davis, Sacramento, CA, United States
| |
Collapse
|
3
|
Sampath V, Martinez M, Caplan M, Underwood MA, Cuna A. Necrotizing enterocolitis in premature infants-A defect in the brakes? Evidence from clinical and animal studies. Mucosal Immunol 2023; 16:208-220. [PMID: 36804483 DOI: 10.1016/j.mucimm.2023.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/03/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023]
Abstract
A key aspect of postnatal intestinal adaptation is the establishment of symbiotic relationships with co-evolved gut microbiota. Necrotizing enterocolitis (NEC) is the most severe disease arising from failure in postnatal gut adaptation in premature infants. Although pathological activation of intestinal Toll-like receptors (TLRs) is believed to underpin NEC pathogenesis, the mechanisms are incompletely understood. We postulate that unregulated aberrant TLR activation in NEC arises from a failure in intestinal-specific mechanisms that tamponade TLR signaling (the brakes). In this review, we discussed the human and animal studies that elucidate the developmental mechanisms inhibiting TLR signaling in the postnatal intestine (establishing the brakes). We then evaluate evidence from preclinical models and human studies that point to a defect in the inhibition of TLR signaling underlying NEC. Finally, we provided a framework for the assessment of NEC risk by screening for signatures of TLR signaling and for NEC prevention by TLR-targeted therapy in premature infants.
Collapse
Affiliation(s)
- Venkatesh Sampath
- Division of Neonatology, Children's Mercy Kansas City, Kansas City, Missouri, USA; School of Medicine, University of Missouri Kansas City, Kansas City, Missouri, USA.
| | - Maribel Martinez
- Division of Neonatology, Children's Mercy Kansas City, Kansas City, Missouri, USA; School of Medicine, University of Missouri Kansas City, Kansas City, Missouri, USA
| | - Michael Caplan
- Department of Pediatrics, North Shore University Health System, Evanston, Illinois, USA
| | - Mark A Underwood
- Department of Pediatrics, University of California Davis, Sacramento, California, USA
| | - Alain Cuna
- Division of Neonatology, Children's Mercy Kansas City, Kansas City, Missouri, USA; School of Medicine, University of Missouri Kansas City, Kansas City, Missouri, USA
| |
Collapse
|
4
|
Bench to bedside - new insights into the pathogenesis of necrotizing enterocolitis. Nat Rev Gastroenterol Hepatol 2022; 19:468-479. [PMID: 35347256 DOI: 10.1038/s41575-022-00594-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/22/2022] [Indexed: 12/12/2022]
Abstract
Necrotizing enterocolitis (NEC) is the leading cause of death and disability from gastrointestinal disease in premature infants. Recent discoveries have shed light on a unifying theorem to explain the pathogenesis of NEC, suggesting that specific treatments might finally be forthcoming. A variety of experiments have highlighted how the interaction between bacterial signalling receptors on the premature intestine and an abnormal gut microbiota incites a pro-inflammatory response in the intestinal mucosa and its underlying endothelium that leads to NEC. Central amongst the bacterial signalling receptors implicated in NEC development is the lipopolysaccharide receptor Toll-like receptor 4 (TLR4), which is expressed at higher levels in the premature gut than in the full-term gut. The high prenatal intestinal expression of TLR4 reflects the role of TLR4 in the regulation of normal gut development, and supports additional studies indicating that NEC develops in response to signalling events that occur in utero. This Review provides new evidence explaining the pathogenesis of NEC, explores new findings indicating that NEC development has origins before birth, and discusses future questions and opportunities for discovery in this field.
Collapse
|
5
|
Donda KT, Torres BA, Khashu M, Maheshwari A. Single Nucleotide Polymorphisms in Neonatal Necrotizing Enterocolitis. Curr Pediatr Rev 2022; 18:197-209. [PMID: 35040407 DOI: 10.2174/1573396318666220117091621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/10/2021] [Accepted: 11/16/2021] [Indexed: 11/22/2022]
Abstract
The etiopathogenesis of necrotizing enterocolitis (NEC) remains unclear, but increasing information suggests that the risk and severity of NEC may be influenced by single nucleotide polymorphisms in many genes. In this article, we have reviewed gene variations that have either been specifically identified in NEC or have been noted in other inflammatory bowel disorders with similar histopathological abnormalities. We present evidence from our own peer-reviewed laboratory studies and data from an extensive literature search in the databases PubMed, EMBASE, and Scopus. To avoid bias in the identification of existing studies, search keywords were short-listed both from our own studies and from PubMed's Medical Subject Heading (MeSH) thesaurus.
Collapse
Affiliation(s)
- Keyur T Donda
- Department of Pediatrics, University of South Florida Health Morsani College of Medicine, Tampa, FL, USA
| | - Benjamin A Torres
- Department of Pediatrics, University of South Florida Health Morsani College of Medicine, Tampa, FL, USA
| | - Minesh Khashu
- Poole Hospital NHS Foundation Trust and Bournemouth University, Poole, United Kingdom
| | - Akhil Maheshwari
- Department of Pediatrics, Johns Hopkins University, Baltimore, ML, USA
| |
Collapse
|
6
|
Kosik K, Szpecht D, Al-Saad SR, Karbowski LM, Kurzawińska G, Szymankiewicz M, Drews K, Wolski H, Seremak-Mrozikiewicz A. Single nucleotide vitamin D receptor polymorphisms (FokI, BsmI, ApaI, and TaqI) in the pathogenesis of prematurity complications. Sci Rep 2020; 10:21098. [PMID: 33273558 PMCID: PMC7713052 DOI: 10.1038/s41598-020-78125-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 11/17/2020] [Indexed: 11/10/2022] Open
Abstract
The vitamin D receptor (VDR), coded by the VDR gene, plays a pivotal role in executing cellular functions when bound by the active form of vitamin D. Gene polymorphisms in this receptor have been increasingly associated with a heightened state of vulnerability to certain diseases. However, limited data is available concerning the role of VDR gene polymorphisms in preterm infant complications. In 114 premature infants (< 32 weeks gestation) we analyze four single nucleotide VDR polymorphisms (rs2228570 (FokI), rs1544410 (BsmI), rs797532 (ApaI), rs731236 (TaqI)) for their association with respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC) and retinopathy of prematurity (ROP). The results show that BPD was almost four times more likely in infants with the genotype CC of ApaI (rs7975232) (OR 3.845; p = 0.038). While both BPD and NEC were 2.1 times more likely to occur in preterm infants with the allele C of ApaI (rs7975232) (respectively: OR 2.111 and OR 2.129, p < 0.05). The ApaI VDR polymorphism appears to influence incidence of BPD and NEC in preterm infants. Considering VDR polymorphisms in future genetic investigations, in preterm complications, may prove clinically relevant.
Collapse
|
7
|
Cuna A, George L, Sampath V. Genetic predisposition to necrotizing enterocolitis in premature infants: Current knowledge, challenges, and future directions. Semin Fetal Neonatal Med 2018; 23:387-393. [PMID: 30292709 PMCID: PMC6626706 DOI: 10.1016/j.siny.2018.08.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The role of genetics in the pathogenesis of necrotizing enterocolitis (NEC) was initially informed by epidemiological data indicating differences in prevalence among different ethnic groups as well as concordance in twins. These early observations, together with major advances in genomic research, paved the way for studies that begin to reveal the contribution of genetics to NEC. Using the candidate gene or pathway approach, several potential pathogenic variants for NEC in premature infants have already been identified. More recently, genome-wide association studies and exome-sequencing based studies for NEC have been reported. These advances, however, are tempered by the lack of adequately powered replication cohorts to validate the accuracy of these discoveries. Despite many challenges, genetic research in NEC is expected to increase, providing new insights into its pathogenesis and bringing the promise of personalized care closer to reality. In this review we provide a summary of genetic studies in NEC along with defining the challenges and possible future approaches.
Collapse
Affiliation(s)
| | | | - Venkatesh Sampath
- Division of Neonatology, Department of Pediatrics, Children's Mercy Kansas City, Kansas City, MO, USA.
| |
Collapse
|
8
|
Surgical necrotizing enterocolitis in extremely premature neonates is associated with genetic variations in an intergenic region of chromosome 8. Pediatr Res 2018; 83. [PMID: 29538362 PMCID: PMC6053310 DOI: 10.1038/pr.2018.33] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
BackgroundTwin studies suggest that genetic factors may account for up to 50% increased risk for necrotizing enterocolitis (NEC), but genome-wide association studies for NEC are lacking.MethodsGenotyping was done on Illumina BeadChip, followed by analysis using PLINK with logistic regression under an additive model.ResultsAmong 751 extremely-low-birth-weight (<1,000 g, >401 g) neonates, 30 had surgical NEC. Two hundred and sixty-one single-nucleotide polymorphisms (SNPs) showed association with NEC at P<0.05, of which 35 were significant at P<10-7. Minor allele(s) in a cluster of SNPs spanning a 43-kb region of chromosome 8 (8q23.3) conferred an odds ratio of 4.72 (95% confidence interval (CI): 2.51-8.88) for elevated risk of NEC. Two smaller clusters on chromosome 14 and chromosome 11 exhibited P values of 10-7-10-8. The chromosome 8 cluster is in an intergenic region between CUB and Sushi multiple domains 3 (-1.43 Mb) and trichorhinophalangeal syndrome I (+542 kb). RNA sequencing in this region identified a potential novel open-reading frame corresponding to a long interspersed element-1 retrotransposable element.ConclusionGenetic variation in an intergenic region of chromosome 8 is associated with increased risk for NEC with a mechanism that is yet to be identified.
Collapse
|
9
|
Esdal HCD, Ghbeis MB, Saltzman DA, Hess D, Hume JR, Reed RC, Berry SA, Hoggard E, Hirsch B, Baughn LB, Schimmenti LA. Necrotizing Enterocolitis in Two Siblings and an Unrelated Infant with Overlapping Chromosome 6q25 Deletions. Mol Syndromol 2018; 9:141-148. [PMID: 29928179 DOI: 10.1159/000488817] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2018] [Indexed: 11/19/2022] Open
Abstract
The pathogenesis of necrotizing enterocolitis (NEC) remains poorly understood but is thought to be multifactorial. There are no specific recurring chromosomal abnormalities previously associated with NEC. We report 3 cases of intestinal necrosis associated with large chromosome 6 deletions. The first patient was found to have a 7.9-Mb deletion of chromosome 6 encompassing over 40 genes, arr[GRCh37] 6q25.3q26(155699183_163554531)×1. The second patient had a 19.5-Mb deletion of chromosome 6 generated by an unbalanced translocation with chromosome 18, 46,XY,der(6)t (6;18)(q25.1;p11.23), arr[GRCh37] 6q25.1q27(151639526_ 171115067)×1, 18p11.32p11.23(131700_7694199)×3, which included the whole 7.9-Mb region deleted in the first patient. The third patient was the younger sibling of the second patient with an identical derivative chromosome 6. The shared abnormal chromosome 6 region includes multiple genes of interest, particularly EZR. Mouse models have demonstrated that Ezr is expressed in microvillar epithelium and helps regulate cell-cell adhesion in the gut. We hypothesize that deletion of this shared region of 6q leads to gastrointestinal vulnerability which may predispose patients to intestinal necrosis.
Collapse
Affiliation(s)
- Hannah C D Esdal
- Department of Pediatrics, University of Minnesota, Minneapolis, USA
| | - Muhammad B Ghbeis
- Division of Cardiovascular Critical Care, Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
| | - Daniel A Saltzman
- Department of Pediatric Surgery, Divisions of, University of Minnesota Masonic Children's Hospital, Minneapolis, USA
| | - Donavon Hess
- Department of Pediatric Surgery, Divisions of, University of Minnesota Masonic Children's Hospital, Minneapolis, USA
| | - Janet R Hume
- Critical Care, University of Minnesota Masonic Children's Hospital, Minneapolis, USA
| | - Robyn C Reed
- Department of Pathology, Children's Hospitals and Clinics of Minnesota, Minneapolis, MN, USA
| | - Susan A Berry
- Genetics and Metabolism, Department of Pediatrics, University of Minnesota Masonic Children's Hospital, Minneapolis, USA
| | - Eric Hoggard
- Division of Pediatric Radiology, Department of Radiology, University of Minnesota Masonic Children's Hospital, Minneapolis, USA
| | - Betsy Hirsch
- Division of Molecular Pathology and Genomics, Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, USA
| | - Linda B Baughn
- Division of Laboratory Genetics and Genomics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Lisa A Schimmenti
- Department of Otorhinolaryngology and Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
10
|
Gond DP, Singh S, Agrawal NK. Testing an association between TLR4 and CXCR1 gene polymorphisms with susceptibility to urinary tract infection in type 2 diabetes in north Indian population. Gene 2017; 641:196-202. [PMID: 29066305 DOI: 10.1016/j.gene.2017.10.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Genetic variations of Toll like receptor 4 (TLR4) and CXC-chemokine receptor type1 (CXCR1), the key elements of innate immune system and their association with urinary tract infection (UTI) were studied in general population. In present study we investigate genetic variation of these genes in diabetic patients (3 to 4 times higher prevalence of UTI in comparison to general population). METHODS A total 1100 subjects (318 diabetic patients with UTI, 324 diabetic patients without UTI, 200 non-diabetic UTI patients and 260 age matched healthy control) were enrolled in the study. SNPs of TLR4 rs4986790, rs4986791 and CXCR1 rs2234671 was assessed by PCR-RFLP and PCR-SSP respectively. RESULTS Statistical analysis revealed that A/G genotype and G allele of TLR4 rs4986790 are significantly associated with UTI in both diabetics and nondiabetic patients in comparison to healthy control. Similarly CT genotype and T allele of TLR4 rs4986791 are also significantly associated with UTI in both groups. We also found that prevalence of A/G genotype of TLR4 rs4986790 and CT genotype of TLR4 rs4986791 are significantly higher in patients of diabetes with UTI in comparison to diabetic patients without UTI. We did not find any association of CXCR1 rs2234671 polymorphism with UTI by comparing with any group. CONCLUSION We found that TLR4 rs4986790 and rs4986791 gene polymorphism is a risk for UTI development in both diabetic and nondiabetic patients in north Indian population.
Collapse
Affiliation(s)
- Dinesh Prasad Gond
- Department of Endocrinology and Metabolism, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Shivendra Singh
- Department of Nephrology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - N K Agrawal
- Department of Endocrinology and Metabolism, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India.
| |
Collapse
|
11
|
A functional ATG16L1 (T300A) variant is associated with necrotizing enterocolitis in premature infants. Pediatr Res 2017; 81:582-588. [PMID: 27893720 PMCID: PMC5714513 DOI: 10.1038/pr.2016.260] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 10/09/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND The genetic basis of dysfunctional immune responses in necrotizing enterocolitis (NEC) remains unknown. We hypothesized that variants in nucleotide binding and oligomerization domain (NOD)-like receptors (NLRs) and autophagy (ATG) genes modulate vulnerability to NEC. METHODS We genotyped a multi-center cohort of premature infants with and without NEC for NOD1, NOD2, ATG16L1, CARD8, and NLRP3 variants. Chi-square tests and logistic regression were used for statistical analysis. RESULTS In our primary cohort (n = 1,015), 86 (8.5%) infants developed NEC. The A allele of the ATG16L1 (Thr300Ala) variant was associated with increased NEC (AA vs. AG vs. GG; 11.3 vs. 8.4 vs. 4.8%, P = 0.009). In regression models for NEC that adjusted for epidemiological confounders, GA (P = 0.033) and the AA genotype (P = 0.038) of ATG16L1 variant were associated with NEC. The association between the A allele of the ATG16L1 variant and NEC remained significant among Caucasian infants (P = 0.02). In a replication cohort (n = 259), NEC rates were highest among infants with the AA genotype but did not reach statistical significance. CONCLUSION We report a novel association between a hypomorphic variant in an autophagy gene (ATG16L1) and NEC in premature infants. Our data suggest that decreased autophagy arising from genetic variants may confer protection against NEC.
Collapse
|
12
|
Abstract
An underlying genetic predisposition to necrotizing enterocolitis (NEC) is increasingly being recognized. Candidate gene or pathway approaches as well as genome-wide approaches are beginning to identify potential pathogenic variants for NEC in premature infants. However, a majority of these studies have not yielded definitive results because of limited sample size and lack of validation. Despite these challenges, understanding the contribution of genetic variation to NEC is important for providing new insights into the pathogenesis of NEC as well as allowing for targeted care of infants with inherent susceptibility. In this review we provide a summary of published genetic association studies in NEC along with defining the challenges and possible future approaches.
Collapse
Affiliation(s)
- Alain Cuna
- Division of Neonatology, Department of Pediatrics, Children's Mercy Hospital, University of Missouri-Kansas City, 2401 Gillham Rd, Kansas City, MO 64108
| | - Venkatesh Sampath
- Division of Neonatology, Department of Pediatrics, Children's Mercy Hospital, University of Missouri-Kansas City, 2401 Gillham Rd, Kansas City, MO 64108.
| |
Collapse
|
13
|
Sampath V, Mulrooney N, Patel AL, Cohen J, Zhang L, Garland J, Lavoie PM, Dagle J, Simpson P. A Potential Role for the NOD1 Variant (rs6958571) in Gram-Positive Blood Stream Infection in ELBW Infants. Neonatology 2017; 112:354-358. [PMID: 28768269 DOI: 10.1159/000477433] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 05/11/2017] [Indexed: 12/23/2022]
Abstract
BACKGROUND The genetic basis of sepsis susceptibility in preterm infants remains understudied. Herein, we investigated the nucleotide binding-oligomerization domain (NOD)-like receptor (NLR) family of immune receptors as putative loci for preterm sepsis susceptibility. OBJECTIVE To determine whether single nucleotide polymorphisms (SNPs) in NLR genes are associated with blood stream infections (BSI) in premature infants. METHODS An international cohort of infants with gestational age (GA) <35 weeks were genotyped for SNPs in the ATG16L1, CARD8, NLRP3, NOD2, and NOD1 genes. χ2 and logistic regression analyses were used to examine relationships between NLR variants and BSI. RESULTS Among 764 infants, 138 developed BSI, 113 had gram-positive bacterial (GPB) BSI, and 28 had gram-negative bacterial (GNB) BSI. Infants with BSI had a lower birth weight and GA (p < 0.001), but did not differ in gender, race, or chorioamnionitis. NLR variants were not associated with GPB or GNB BSI in the entire cohort. The CC genotype of the NOD1 SNP (rs6958571) was associated with increased GPB BSI in extremely low birth weight (ELBW, birth weight <1,000 g) infants (OR = 3.3, 95% CI: 1.4-7.5, p = 0.003, n = 362) and in Caucasian infants (OR = 2.5, 95% CI: 1.2-5.4, p = 0.016, n = 535). Regression models adjusting for clinical variables identified ELBW status and the NOD1 CC genotype as risk factors for GPB BSI in Caucasian infants. CONCLUSIONS In this study investigating relationships between NLR variants and sepsis in infants with GA <35 weeks, the NOD1 (rs6958571) SNP was associated with GPB BSI in Caucasian infants and ELBW infants. Replication of our results in an independent cohort would support a role for NLR variants in determining sepsis risk in ELBW infants.
Collapse
|
14
|
Necrotizing Enterocolitis Is Not Associated With Sequence Variants in Antioxidant Response Genes in Premature Infants. J Pediatr Gastroenterol Nutr 2016; 62:420-3. [PMID: 26426434 PMCID: PMC5055643 DOI: 10.1097/mpg.0000000000000988] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Reactive oxygen species mediate intestinal injury in necrotizing enterocolitis (NEC), and yet the contribution of antioxidant response (ARE) gene polymorphisms to NEC risk remains unknown. Premature infants recruited in a multicenter study were genotyped for 6 ARE variants. Among 637 infants, 52 had NEC, and 22 developed surgical NEC. Gestational age <28 weeks (P < 0.02) and African American race (P = 0.03) were associated with NEC. The NFE2L2 (rs6721961), SOD2 (rs4880), GSTP1 (rs1695), NQO1 (rs1800566), GCLC (rs17883901), and HMOX1 (rs2071747) variants were not associated with medical or surgical NEC. This study does not support a role for common deleterious ARE variants in NEC.
Collapse
|
15
|
NOD2 Loss-of-Function Mutations and Risks of Necrotizing Enterocolitis or Focal Intestinal Perforation in Very Low-birth-weight Infants. Inflamm Bowel Dis 2016; 22:249-56. [PMID: 26752461 DOI: 10.1097/mib.0000000000000658] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND NOD2 loss-of-function mutations, that is, R702W [rs2066844], G908R [rs2066845], and Leu1007fsinsC [rs5743293], have been linked to inflammatory bowel diseases. It is yet unknown whether these variants are also associated with necrotizing enterocolitis (NEC) or focal intestinal perforation (FIP) in infants of very low birth weight (VLBW). METHODS To test this hypothesis, we genotyped 9082 VLBW infants with European ancestry enrolled in a prospective, population-based cohort study of the German Neonatal Network. We assessed the effect of the NOD2 gene variants on the risk for major morbidities of the gastrointestinal tract, that is, NEC/FIP requiring surgery in multivariable logistic regression analyses. RESULTS In the whole cohort of VLBW infants, carriers of ≥ 2 NOD2 variant alleles had an increased risk for NEC requiring surgery (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.27-10.04; P = 0.03) and NEC or FIP requiring surgery (OR, 3.81; 95% CI, 1.70-8.51; P = 0.004) as compared with wild-type genotypes. In a multivariable logistic regression analysis including gestational age, birth weight, gender, multiple birth, and inborn delivery, the association between ≥ 2 NOD2 variant alleles and NEC surgery (OR, 4.14; 95% CI, 1.41-12.12; P = 0.009), FIP surgery (OR, 3.50; 95% CI, 1.02-12.04; P = 0.047), and NEC or FIP surgery (OR, 4.10; 95% CI, 1.74-9.73; P = 0.001) proved to be independent. We also performed a regression analysis in the subgroup of infants with available information on Lactobacillus acidophilus/Bifidobacterium infantis probiotic supplementation (n = 3638). Although probiotics had a protective effect on NEC and NEC or FIP requiring surgery, the NOD2 variants had no significant impact in this subgroup. CONCLUSIONS VLBW infants carrying ≥ 2 NOD2 genetic risk factors of inflammatory bowel disease in adults have an increased risk for severe gastrointestinal complications, such as NEC requiring surgery. Therefore, infants might benefit from NOD2 genotyping followed by supplementation with probiotics. Replication studies are needed along with genome-wide arrays to allow risk-adapted prevention and therapeutic strategies.
Collapse
|
16
|
Frémond ML, Viala J, Tréton X, Roy M, Berrebi D, Gottrand F, Bonnard A, Martinez-Vinson C, Hugot JP. Digestive perianastomotic ulcerations and Crohn's disease. J Crohns Colitis 2014; 8:1624-31. [PMID: 25107846 DOI: 10.1016/j.crohns.2014.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 06/29/2014] [Accepted: 06/30/2014] [Indexed: 02/08/2023]
Abstract
BACKGROUND AND AIMS Digestive perianastomotic ulcerations (DPAU) have been occasionally reported as late complications of neonatal or childhood surgery. METHODS We report here a series of 14 new cases. RESULTS Cases were revealed by severe anemia, diarrhea, abdominal pain and growth failure in average 11.5 years after surgery. Ulcerations were most often multiple (n=11), located on the upper part of ileocolonic anastomoses (n=12) and difficult to treat. No granulomas were seen but lymphoid follicles were frequent. In addition, either ASCA or ANCA were positive in 4/9 tested patients and 8/11 genotyped patients exhibited a NOD2 mutation (P<0.0002 when compared to French healthy controls). CONCLUSION Altogether, these findings argue for common physiopathological features between DPAU and Crohn's disease and for a prospective follow-up of selected operated children to explore the early events involved in gut inflammatory lesions.
Collapse
Affiliation(s)
- Marie-Louise Frémond
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France
| | - Jérome Viala
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France; Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France; INSERM UMR1149, Centre de Recherche sur l'inflammation Paris Montmartre, 75018 Paris, France
| | - Xavier Tréton
- Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France; INSERM UMR1149, Centre de Recherche sur l'inflammation Paris Montmartre, 75018 Paris, France; Assistance Publique-Hôpitaux de Paris, Service de Gastroentérologie, Hôpital Beaujon, 92000 Clichy, France
| | - Maryline Roy
- Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France; INSERM UMR1149, Centre de Recherche sur l'inflammation Paris Montmartre, 75018 Paris, France
| | - Dominique Berrebi
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France; Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France; INSERM UMR1149, Centre de Recherche sur l'inflammation Paris Montmartre, 75018 Paris, France
| | | | - Arnaud Bonnard
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France; Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France
| | - Christine Martinez-Vinson
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France
| | - Jean-Pierre Hugot
- Assistance Publique-Hôpitaux de Paris, Services des Maladies Digestives et Respiratoires de l'enfant, Service de Chirurgie Digestive et Service de Cytologie et Pathologie, Hôpital Robert Debré, 75019 Paris, France; Université Paris-Diderot UMR 1149, Labex Inflamex, 75018 Paris, France; INSERM UMR1149, Centre de Recherche sur l'inflammation Paris Montmartre, 75018 Paris, France.
| |
Collapse
|
17
|
Relevance of single-nucleotide polymorphisms in human TLR genes to infectious and inflammatory diseases and cancer. Genes Immun 2014; 15:199-209. [DOI: 10.1038/gene.2014.10] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 01/30/2014] [Accepted: 02/03/2014] [Indexed: 02/07/2023]
|
18
|
Abstract
Necrotizing enterocolitis (NEC) has largely been present in neonatal intensive care units for the past 60 years. NEC prevalence has corresponded with the continued development and sophistication of neonatal intensive care. Despite major efforts towards its eradication, NEC has persisted and appears to be increasing in some centers. The pathophysiology of this disease remains poorly understood. Several issues have hampered our quest to develop a better understanding of this disease. These include the fact that what we have historically termed 'NEC' appears to be several different diseases. Animal models that are commonly used to study NEC pathophysiology and treatment do not directly reflect the most common form of the disease seen in human infants. The pathophysiology appears to be multifactorial, reflecting several different pathways to intestinal necrosis with different inciting factors. Spontaneous intestinal perforations, ischemic bowel disease secondary to cardiac anomalies as well as other entities that are clearly different from the most common form of NEC seen in preterm infants have been put into the same database. Here I describe some of the different forms of what has been called NEC and make some comments on its pathophysiology, where available studies suggest involvement of genetic factors, intestinal immaturity, hemodynamic instability, inflammation and a dysbiotic microbial ecology. Currently utilized approaches for the diagnosis of NEC are presented and innovative technologies for the development of diagnostic and predictive biomarkers are described. Predictions for future strategies are also discussed.
Collapse
Affiliation(s)
- Josef Neu
- Division of Neonatology, Department of Pediatrics, College of Medicine, University of Florida, Gainesville, Fla., USA
| |
Collapse
|
19
|
Ziakas PD, Prodromou ML, El Khoury J, Zintzaras E, Mylonakis E. The role of TLR4 896 A>G and 1196 C>T in susceptibility to infections: a review and meta-analysis of genetic association studies. PLoS One 2013; 8:e81047. [PMID: 24282567 PMCID: PMC3840016 DOI: 10.1371/journal.pone.0081047] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 10/17/2013] [Indexed: 01/13/2023] Open
Abstract
Background Toll-like receptor 4 plays a role in pathogen recognition, and common polymorphisms may alter host susceptibility to infectious diseases. Purpose To review the association of two common polymorphisms (TLR4 896A>G and TLR4 1196C>T) with infectious diseases. Data Sources We searched PubMed and EMBASE up to March 2013 for pertinent literature in English, and complemented search with references lists of eligible studies. Study Selection We included all studies that: reported an infectious outcome; had a case-control design and reported the TLR4 896A>G and/or TLR4 1196C>T genotype frequencies; 59 studies fulfilled these criteria and were analyzed. Data Extraction Two authors independently extracted study data. Data Synthesis The generalized odds ratio metric (ORG) was used to quantify the impact of TLR4 variants on disease susceptibility. A meta-analysis was undertaken for outcomes reported in >1 study. Eleven of 37 distinct outcomes were significant. TLR4 896 A>G increased risk for all parasitic infections (ORG 1.59; 95%CI 1.05-2.42), malaria (1.31; 95%CI 1.04-1.66), brucellosis (2.66; 95%CI 1.66-4.27), cutaneous leishmaniasis (7.22; 95%CI 1.91-27.29), neurocysticercosis (4.39; 95%CI 2.53-7.61), Streptococcus pyogenes tonsillar disease (2.93; 95%CI 1.24-6.93) , typhoid fever (2.51; 95%CI 1.18-5.34) and adult urinary tract infections (1.98; 95%CI 1.04-3.98), but was protective for leprosy (0.36; 95%CI 0.22-0.60). TLR4 1196 C>T effects were similar to TLR4 896 A>G for brucellosis, cutaneous leishmaniasis, leprosy, typhoid fever and S. pyogenes tonsillar disease, and was protective for bacterial vaginosis in pregnancy (0.55; 95%CI 0.31-0.98) and Haemophilus influenzae tonsillar disease (0.42; 95%CI 0.17-1.00). The majority of significant associations were among predominantly Asian populations and significant associations were rare among European populations. Conclusions Depending on the type of infection and population, TLR4 polymorphisms are associated with increased, decreased or no difference in infectious disease. This may be due to differential functional expression of TLR4, the co-segregation of TLR4 variants or a favorable inflammatory response.
Collapse
Affiliation(s)
- Panayiotis D. Ziakas
- Division of Infectious Diseases, Rhode Island Hospital, Providence, Rhode Island, United States of America
- Warren Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Michael L. Prodromou
- Division of Infectious Diseases, Rhode Island Hospital, Providence, Rhode Island, United States of America
- Department of Medicine, Warren Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Joseph El Khoury
- Center for Immunology and Inflammatory Diseases and Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts,United States of America
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Elias Zintzaras
- Center for Clinical Evidence Synthesis, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, Massachusetts, United States of America
- Department of Biomathematics, School of Medicine, University of Thessaly, Larissa, Greece
| | - Eleftherios Mylonakis
- Division of Infectious Diseases, Rhode Island Hospital, Providence, Rhode Island, United States of America
- Warren Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
- * E-mail:
| |
Collapse
|
20
|
Sampath V, Mulrooney NP, Garland JS, He J, Patel AL, Cohen JD, Simpson PM, Hines RN. Toll-like receptor genetic variants are associated with Gram-negative infections in VLBW infants. J Perinatol 2013; 33:772-7. [PMID: 23867959 PMCID: PMC4465440 DOI: 10.1038/jp.2013.80] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 05/15/2013] [Accepted: 06/06/2013] [Indexed: 12/25/2022]
Abstract
OBJECTIVE To test the hypothesis that single-nucleotide polymorphisms (SNPs) in Toll-like receptor (TLR) genes alter susceptibility to bacterial infections and modulate white blood cell (WBC) counts during infections in very low birth weight (VLBW) infants (birth weight <1500 g). STUDY DESIGN VLBW infants recruited in a multicenter study were genotyped for nine functional TLR SNPs and associations between SNPs and infection rates examined. WBC counts obtained during infections were compared among infants with and without SNPs. RESULT In our cohort (n=408), 90 infants developed bacterial infections. Presence of TLR4 (rs4986790 and rs4986791) variants were associated with Gram-negative (G-ve) infections. Female infants heterozygous for the X-linked IRAK1 (rs1059703) SNP had less G-ve infections. In regression models controlling for confounders, the TLR4 (rs4986790) SNP was associated with increased G-ve infections. The TLR5 (rs5744105) variant was associated with elevated WBC counts during infections. CONCLUSION TLR genetic variants can contribute to increased risk of bacterial infections and altered immune responses in VLBW infants.
Collapse
Affiliation(s)
- Venkatesh Sampath
- Department of Pediatrics, Medical College of Wisconsin, and Children’s Research Institute, Children’s Hospital and Health Systems, Milwaukee, WI, USA,Corresponding author: Venkatesh Sampath, Neonatology, Suite 410, Children’s Corporate Center, 999 N.92nd Street, Wauwatosa, WI 53226; Ph: (414) 266 6820; Fax: (414) 266 6979;
| | | | - Jeffery S. Garland
- Department of Pediatrics, Wheaton Franciscan Health Care, Milwaukee, WI, USA
| | - Jie He
- Department of Pediatrics, Medical College of Wisconsin, and Children’s Research Institute, Children’s Hospital and Health Systems, Milwaukee, WI, USA
| | - Aloka L. Patel
- Department of Pediatrics, Rush University Medical Center, Chicago, IL, USA
| | | | - Pippa M. Simpson
- Department of Pediatrics, Medical College of Wisconsin, and Children’s Research Institute, Children’s Hospital and Health Systems, Milwaukee, WI, USA
| | - Ronald N. Hines
- Department of Pediatrics, Medical College of Wisconsin, and Children’s Research Institute, Children’s Hospital and Health Systems, Milwaukee, WI, USA
| |
Collapse
|
21
|
Affiliation(s)
- James L. Wynn
- Assistant Professor of Pediatrics, Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN,
| |
Collapse
|
22
|
Ng PC, Chan KYY, Poon TCW. Biomarkers for prediction and diagnosis of necrotizing enterocolitis. Clin Perinatol 2013; 40:149-59. [PMID: 23415270 DOI: 10.1016/j.clp.2012.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This article summarizes the commonly used biomarkers currently available for diagnosis of necrotizing enterocolitis. The most exciting advances in diagnostic tests were the use of new nucleic acid sequencing techniques (eg, next-generation sequencing) and molecular screening methods (eg, proteomics and microarray analysis) for the discovery of novel biomarkers. The new technology platform coupled with stringent protocols of biomarker discovery and validation would enable neonatologists to study biologic systems at a level never before possible and discover unique biomarkers for specific organ injury and/or disease entity.
Collapse
Affiliation(s)
- Pak C Ng
- Department of Paediatrics, The Chinese University of Hong Kong, Shatin NT, Hong Kong SAR, The People's Republic of China.
| | | | | |
Collapse
|
23
|
Moore JE. Newer monitoring techniques to determine the risk of necrotizing enterocolitis. Clin Perinatol 2013; 40:125-34. [PMID: 23415268 DOI: 10.1016/j.clp.2012.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Necrotizing enterocolitis affects up to 10% of neonates who are born weighing less than 1500 g. It has a high rate of morbidity and mortality, and predicting infants who will be affected has so far been unsuccessful. In this article, a number of new methods are discussed from the literature to determine if any currently available techniques may allow for the identification of patients who are at increased risk for developing this potentially lethal disease.
Collapse
Affiliation(s)
- James E Moore
- Department of Pediatrics, University of Texas, Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
| |
Collapse
|
24
|
[Genetic susceptibility to infections]. Internist (Berl) 2011; 52:1053-4, 1056-8, 1060. [PMID: 21842176 DOI: 10.1007/s00108-011-2858-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Infectious diseases are among the leading causes of morbidity and mortality worldwide. The spectrum of clinical manifestations of infections is highly variable, ranging from asymptomatic infection or mild illness to rapid progression of disease and death. Twin studies first showed an inheritable component of many infections and epidemiological and genetic studies revealed definite gene loci and polymorphisms for most of the clinically relevant infectious diseases. Reliable genetic markers which represent susceptibility or resistance to infections, prognosis of disease and response to treatment are necessary to define risk populations and to plan therapy regimens. Genetic research can also help in identifying target structures for novel therapy strategies and anitimicrobial agents. In this article the genetic background of important infections is reviewed and examples of successful exploitation of genetic findings and translation into practical medicine are given.
Collapse
|
25
|
The NFKB1 (g.-24519delATTG) variant is associated with necrotizing enterocolitis (NEC) in premature infants. J Surg Res 2011; 169:e51-7. [PMID: 21529841 DOI: 10.1016/j.jss.2011.03.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 02/11/2011] [Accepted: 03/04/2011] [Indexed: 01/04/2023]
Abstract
OBJECTIVE While it is known that gene-environment interactions contribute to necrotizing enterocolitis (NEC) pathogenesis, characterization of genetic risk-factors that can predict NEC in preterm infants remains nascent. We hypothesized that altered intestinal immune responses arising from sequence variation in the toll-like receptor (TLR) pathway genes contribute to NEC susceptibility. MATERIALS AND METHODS Very low birth weight (VLBW) infants were recruited prospectively in a multi-center, cohort study involving collection of blood samples along with collation of clinical information. DNA obtained from blood samples was used to genotype nine single nucleotide polymorphisms (SNPs) in eight TLR pathway genes by single-base extension. Prevalence of the variant allele was compared between cases and controls using Fisher's exact test. RESULTS In our cohort of 271 infants, 15 infants (5.6%) developed NEC, and five died from it. Infants with NEC were less mature (P < 0.001), and were more likely to be African-American (P = 0.007). SNPs in the TLR2, TLR4, TLR5, TLR9, IRAK1, and TIRAP genes were not associated with NEC. The NFKB1 (g.-24519delATTG) variant was present in all infants with NEC but only in 65% of infants without NEC (P = 0.003), while the NFKBIA (g.-1004A>G) variant was present in 13.3% of infants with NEC but in 49% of infants without NEC (P = 0.007). After correcting for multiple comparisons, the NFKB1 and NFKBIA variants remained associated with NEC (P < 0.05). CONCLUSIONS These data suggest that TLR genetic variants can alter susceptibility to NEC in VLBW infants and support the hypothesis that genetically programmed differences in the innate immune response contribute to NEC pathogenesis.
Collapse
|
26
|
Yin X, Hou T, Liu Y, Chen J, Yao Z, Ma C, Yang L, Wei L. Association of Toll-like receptor 4 gene polymorphism and expression with urinary tract infection types in adults. PLoS One 2010; 5:e14223. [PMID: 21151974 PMCID: PMC2997054 DOI: 10.1371/journal.pone.0014223] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2010] [Accepted: 11/11/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Innate immunity of which Toll-like receptor (TLR) 4 and CXCR1 are key elements plays a central role in the development of urinary tract infection (UTI). Although the relation between the genetics of TLR4 and CXCR1 and UTI is investigated partly, the polymorphisms and expression of TLR4 and CXCR1 in different types of UTI in adults are not extremely clear. METHODOLOGY/PRINCIPAL FINDINGS This study investigates the presence of TLR4 A (896) G and CXCR1 G (2608) C polymorphisms in 129 UTI patients using RFLP-PCR. Gene and allelic prevalence were compared with 248 healthy controls. Flow cytometry was used to detect TLR4 and CXCR1 expression in the monocytes of UTI patients and healthy controls. TLR4 (896) AG genotype and TLR4 (896) G allele had higher prevalence in UTI (especially in acute cystitis and urethritis) patients, whereas CXCR1 (2608) GC genotype and CXCR1 (2608) C allele had lower prevalence in UTI patients than controls. TLR4 expression was significantly lower in chronic UTI patients than in acute pyelonephritis or healthy controls. CXCR1 expression was similar in both controls and patients. TLR4 expression in chronic UTI patients after astragalus treatment was higher than pre-treatment. CONCLUSIONS The results indicate the relationship between the carrier status of TLR4 (896) G alleles and the development of UTI, especially acute cystitis and urethritis, in adults. TLR4 expression levels are correlated with chronic UTI.
Collapse
Affiliation(s)
- Xiaolin Yin
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
| | - Tianwen Hou
- Department of Laboratory Medicine, Bethune International Peace Hospital, Shijiazhuan, China
| | - Ying Liu
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
| | - Jing Chen
- Department of Laboratory Medicine, Bethune International Peace Hospital, Shijiazhuan, China
| | - Zhiyan Yao
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
| | - Cuiqing Ma
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
| | - Lijuan Yang
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
| | - Lin Wei
- Department of Immunology, Hebei Medical University, Shijiazhuan, China
- * E-mail:
| |
Collapse
|
27
|
Abstract
Neonatal septic shock is a devastating condition associated with high morbidity and mortality. Definitions for the sepsis continuum and treatment algorithms specific for premature neonates are needed to improve studies of septic shock and assess benefit from clinical interventions. Unique features of the immature immune system and pathophysiologic responses to sepsis, particularly those of extremely preterm infants, necessitate that clinical trials consider them as a separate group. Keen clinical suspicion and knowledge of risk factors will help to identify those neonates at greatest risk for development of septic shock. Genomic and proteomic approaches, particularly those that use very small sample volumes, will increase our understanding of the pathophysiology and direct the development of novel agents for prevention and treatment of severe sepsis and shock in the neonate. Although at present antimicrobial therapy and supportive care remain the foundation of treatment, in the future immunomodulatory agents are likely to improve outcomes for this vulnerable population.
Collapse
|
28
|
Abstract
Neonatal sepsis continues to take a devastating toll globally. Although adequate to protect against invasive infection in most newborns, the distinct function of neonatal innate host defense coupled with impairments in adaptive immune responses increases the likelihood of acquiring infection early in life, with subsequent rapid dissemination and death. Unique differences exist between neonates and older populations with respect to the capacity, quantity, and quality of innate host responses to pathogens. Recent characterization of the age-dependent maturation of neonatal innate immune function has identified novel translational approaches that may lead to improved diagnostic, prophylactic, and therapeutic modalities.
Collapse
|
29
|
Patel RM, Lin PW, Kater CE, Arnhold IJ, Rocha A, Nicolau W, Bloise W. Developmental biology of gut-probiotic interaction. Gut Microbes 2010; 1:186-95. [PMID: 21327024 PMCID: PMC3023598 DOI: 10.4161/gmic.1.3.12484] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2010] [Revised: 05/24/2010] [Accepted: 05/26/2010] [Indexed: 02/06/2023] Open
Abstract
While our current knowledge of probiotic interaction in the developing gut remains poorly understood, emerging science is providing greater biological insight into their mechanism of action and therapeutic potential for human disease. Given their beneficial effects, probiotics remain promising agents in neonatal gastrointestinal disorders. Probiotics may restore or supply essential bacterial strains needed for gut maturation and homeostasis, particularly in hosts where this process has been disrupted. Here we highlight the unique characteristics of developing intestinal epithelia with a focus on gut development and colonization as well as the inflammatory propensity of immature epithelia. Additionally, we review potential mechanisms of beneficial probiotic interaction with immature intestinal epithelia including immunomodulation, upregulation of cytoprotective genes, prevention and regulation of apoptosis and maintenance of barrier function. Improved knowledge of gut-probiotic interaction in developing epithelia will allow for a better understanding of how probiotics exert their beneficial effects and help guide their therapeutic use.
Collapse
|
30
|
Abstract
PURPOSE OF REVIEW This review examines recent developments in human genetic susceptibility to enteropathogens that cause infectious diarrhea. RECENT FINDINGS The affinity of specific norovirus genogroups to different histoblood group antigens (HBGAs) on secretor cells has been studied in different epidemiologic studies. HBGAs are also used as receptors by Vibrio cholerae with different degrees of affinity between biotypes. Polymorphisms in the CD14, lactoferrin and osteoprotegerin promoter genes were associated to diarrhea in travelers. Single nucleotide polymorphisms in the IL-8 genes are also associated to increased risk for enteroaggregative Escherichia coli and Clostridium difficile infection. IL-10 haplotypes were associated to enterotoxigenic E. coli associated diarrhea in exposed individuals. A family-based study showed a significant association of the LPLUNC1 gene and cholera. The major histocompatibility complex class II antigens are associated to different degrees of susceptibility and resistance to Salmonella, Cryptosporidium and Entamoeba infection. SUMMARY Variants in genes that encode molecules that mediate attachment, pathogen recognition, inflammatory cytokine response, innate and acquired immunity are being identified as determinants of host genetic susceptibility to infectious diarrhea.
Collapse
|
31
|
Young C, Sharma R, Handfield M, Mai V, Neu J. Biomarkers for infants at risk for necrotizing enterocolitis: clues to prevention? Pediatr Res 2009; 65:91R-97R. [PMID: 19190533 PMCID: PMC2929681 DOI: 10.1203/pdr.0b013e31819dba7d] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Necrotizing enterocolitis (NEC) is the most common severe gastrointestinal emergency that affects premature newborns. This disease often has a rapid onset with few, if any, antecedent signs that can be used to reliably predict its occurrence. Its rapid onset and progression to death, as well as its severe morbidity when the infant survives, begs for early diagnostic tools that may be used in determining those infants who would be at greatest risk for development of the disease and for whom early preventative measures could be targeted. Although studies have suggested efficacy of several techniques such as breath hydrogen, inflammatory mediators in blood, urine or stool, and genetic markers, these all have drawbacks limiting their use. The application of newly developed "omic" approaches may provide biomarkers for early diagnosis and targeted prevention of this disease.
Collapse
Affiliation(s)
- Christopher Young
- Department of Pediatrics, University of Florida, Gainesville, Florida 32610
| | - Renu Sharma
- Department of Pediatrics, University of Florida, Jacksonville, Florida 32209
| | - Martin Handfield
- Department of Oral Biology and Center for Molecular Microbiology, University of Florida, Gainesville, Florida 32610
| | - Volker Mai
- Department of Microbiology, University of Florida, Gainesville, Florida 32610
| | - Josef Neu
- Department of Pediatrics, University of Florida, Gainesville, Florida 32610
| |
Collapse
|
32
|
Schlapbach LJ, Aebi C, Fisch U, Ammann RA, Otth M, Bigler S, Nelle M, Berger S, Kessler U. Higher cord blood levels of mannose-binding lectin-associated serine protease-2 in infants with necrotising enterocolitis. Pediatr Res 2008; 64:562-6. [PMID: 18596574 DOI: 10.1203/pdr.0b013e3181841335] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Necrotising enterocolitis (NEC) causes significant morbidity and mortality in premature infants. The role of innate immunity in the pathogenesis of NEC remains unclear. Mannose-binding lectin (MBL) recognizes microorganisms and activates the complement system via MBL-associated serine protease-2 (MASP-2). The aim of this study was to investigate whether MBL and MASP-2 are associated with NEC. This observational case-control study included 32 infants with radiologically confirmed NEC and 64 controls. MBL and MASP-2 were measured in cord blood using ELISA. Multivariate logistic regression was performed. Of the 32 NEC cases (median gestational age, 30.5 wk), 13 (41%) were operated and 5 (16%) died. MASP-2 cord blood concentration ranged from undetectable (<10 ng/mL) to 277 ng/mL. Eighteen of 32 (56%) NEC cases had higher MASP-2 levels (> or =30 ng/mL) compared with 22 of 64 (34%) controls (univariate OR 2.46; 95% CI 1.03-5.85; p = 0.043). Higher cord blood MASP-2 levels were significantly associated with an increased risk of NEC in multivariate analysis (OR 3.00; 95% CI 1.17-7.93; p = 0.027). MBL levels were not associated with NEC (p = 0.64). In conclusion, infants later developing NEC had significantly higher MASP-2 cord blood levels compared with controls. Higher MASP-2 may favor complement-mediated inflammation and could thereby predispose to NEC.
Collapse
|
33
|
Neu J, Mshvildadze M, Mai V. A roadmap for understanding and preventing necrotizing enterocolitis. Curr Gastroenterol Rep 2008; 10:450-457. [PMID: 18799119 DOI: 10.1007/s11894-008-0084-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Necrotizing enterocolitis (NEC) is the most common severe gastrointestinal emergency that affects newborns. Its etiology is still undetermined. Most of our knowledge of this disease stems from epidemiologic studies, clinical experience, and studies using animal models that do not directly represent the disease in premature infants. An immature intestine that is colonized by bacteria is a prerequisite for the pathogenesis of NEC. Although causative microbes have not been found, newly developed analytic techniques now allow the detection of noncultivatable microbes and the determination of their overall diversity and metabolic capabilities. The National Institutes of Health Human Microbiome Roadmap Project is likely to generate new information highly germane to understanding NEC. Newly developed proteomic and metabolomic approaches also offer exciting new potential for early diagnosis and prevention of this disease in infants at highest risk.
Collapse
Affiliation(s)
- Josef Neu
- 1600 Southwest Archer Road, Gainesville, FL 32610, USA.
| | | | | |
Collapse
|
34
|
Frequencies of genetic polymorphisms of TLR4 and CD14 and of HLA-DQ genotypes in children with celiac disease, type 1 diabetes mellitus, or both. J Pediatr Gastroenterol Nutr 2008; 47:283-7. [PMID: 18728522 DOI: 10.1097/mpg.0b013e31816de885] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Besides the central role of the adaptive immune system, a disturbance of innate immunity is also involved in the pathogenesis of celiac disease (CD). Inasmuch as CD and type 1 diabetes mellitus (T1DM) frequently coexist because of a common genetic predisposition, our aim was to study the frequency of CD14 C-260T and TLR4 A+896G single nucleotide polymorphisms (SNPs) and the distribution of HLA-DQ genotypes in children affected by CD, T1DM, or both. PATIENTS AND METHODS TLR4 and CD14 SNPs were tested by polymerase chain reaction, followed by restriction fragment length polymorphism analysis in 80 children with T1DM, 100 children with CD, and 47 children with both CD and T1DM. Determination of HLA-DQ alleles was done by sequence-specific polymerase chain reaction. Frequencies were compared with those of healthy control children. RESULTS The prevalence of the homozygous CD14 C-260TT genotype was significantly (P = 0.0081) lower in children with T1DM but not in those with CD and T1DM, compared with control children. No difference was found in the genotype and allele frequencies of TLR4 between the studied groups. In patients with T1DM, the frequency of the homozygous HLA-DQ8 genotype was significantly higher than in CD, whereas the frequency of homozygous or heterozygous HLA-DQ2 genotypes did not differ from that in control children. In patients with CD, both homozygous and heterozygous HLA-DQ2 genotypes were significantly more frequent than in the control and T1DM groups, and no elevation in the frequency of the HLA-DQ8 genotypes was observed. In patients with T1DM and those with CD and T1DM, the occurrence of HLA-DQ2/8 heterozygosity was significantly higher than in children with CD only and in control children. CONCLUSIONS Our results suggest that in patients with T1DM, the CD14 C-260TT homozygous genotype increases the risk for the development of CD. The distribution of HLA-DQ genotype is different in children with CD and T1DM than in children with CD or T1DM only. Determination of the HLA-DQ genotype in children with T1DM may help in estimating the risk for the development of CD.
Collapse
|
35
|
Abstract
The outcome of sepsis and septic shock has not significantly improved in recent decades despite the development of numerous drugs and supportive care therapies. To reduce sepsis-related mortality, a better understanding of molecular mechanism(s) associated with the development of sepsis and sepsis-related organ injury is essential. There is increasing evidence that Toll-like receptors (TLRs) play a key role in the mediation of systemic responses to invading pathogens during sepsis. However, the role of TLRs in the development of sepsis and in sepsis-related organ injury remains debatable. In this review, we focus on the biological significance of TLRs during sepsis. Medline was searched for pertinent publications relating to TLRs, with emphasis on their clinical and pathophysiological importance in sepsis. In addition, a summary of the authors' own experimental data from this field was set in the context of current knowledge regarding TLRs. In both animal models and human sepsis, TLRs are highly expressed on monocytes/macrophages, and this TLR expression may not simply be a ligand-specific response in such an environment. The fact that TLR signaling enables TLRs to recognize harmful mediators induced by invading pathogens may be associated with a positive feedback loop for the inflammatory response among different cell populations. This mechanism(s) may contribute to the organ dysfunction and mortality that occurs in sepsis. A better understanding of TLR biology may unveil novel therapeutic approaches for sepsis.
Collapse
|
36
|
Schnabl KL, Aerde JEV, Thomson ABR, Clandinin MT. Necrotizing enterocolitis: A multifactorial disease with no cure. World J Gastroenterol 2008; 14:2142-61. [PMID: 18407587 PMCID: PMC2703838 DOI: 10.3748/wjg.14.2142] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Necrotizing enterocolitis is an inflammatory bowel disease of neonates with significant morbidity and mortality in preterm infants. Due to the multifactorial nature of the disease and limitations in disease models, early diagnosis remains challenging and the pathogenesis elusive. Although preterm birth, hypoxic-ischemic events, formula feeding, and abnormal bacteria colonization are established risk factors, the role of genetics and vasoactive/inflammatory mediators is unclear. Consequently, treatments do not target the specific underlying disease processes and are symptomatic and surgically invasive. Breast-feeding is the most effective preventative measure. Recent advances in the prevention of necrotizing enterocolitis have focused on bioactive nutrients and trophic factors in human milk. Development of new disease models including the aspect of prematurity that consistently predisposes neonates to the disease with multiple risk factors will improve our understanding of the pathogenesis and lead to discovery of innovative therapeutics.
Collapse
|
37
|
Lin PW, Nasr TR, Stoll BJ. Necrotizing enterocolitis: recent scientific advances in pathophysiology and prevention. Semin Perinatol 2008; 32:70-82. [PMID: 18346530 DOI: 10.1053/j.semperi.2008.01.004] [Citation(s) in RCA: 216] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Necrotizing enterocolitis (NEC) is a leading cause of morbidity and mortality among infants in the neonatal intensive care unit. Here we review the epidemiology and pathophysiology of NEC, with an emphasis on the latest research findings and potential areas for future research. NEC continues to be one of the most devastating and unpredictable diseases affecting premature infants. Despite decades of research, the pathogenesis of this disease remains unclear, and prevention and treatment strategies are limited. Hopefully, future studies aimed at understanding premature intestinal defenses, commensal or probiotic bacterial influences, and possible genetic predisposition will lead to the improvement of prevention and treatment strategies.
Collapse
Affiliation(s)
- Patricia W Lin
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
| | | | | |
Collapse
|
38
|
Gribar SC, Anand RJ, Sodhi CP, Hackam DJ. The role of epithelial Toll-like receptor signaling in the pathogenesis of intestinal inflammation. J Leukoc Biol 2007; 83:493-8. [PMID: 18160540 DOI: 10.1189/jlb.0607358] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Emerging evidence suggests that the innate immune system, comprised of Toll-like receptors (TLRs) and their associated molecules, plays a pivotal role in the regulation of intestinal inflammation and in the response to invading pathogens. Although TLRs are thought to have predominantly beneficial effects in pathogen recognition and bacterial clearance by leukocytes, their dysregulation and unique signaling effects within intestinal epithelia in the setting of inflammation may have devastating consequences. For instance, activation of TLR4 in enterocytes leads to an inhibition of enterocyte migration and proliferation as well as the induction of enterocyte apoptosis-factors that would be expected to promote intestinal injury while inhibiting intestinal repair. TLR signaling has been shown to be abnormal in several intestinal inflammatory diseases, including Crohn's disease, ulcerative colitis, and necrotizing enterocolitis. This review serves to examine the evidence regarding the patterns of expression and signaling of TLRs in the intestinal mucosa at basal levels and during physiologic stressors to gain insights into the pathogenesis of intestinal inflammation. We conclude that the data reviewed suggest that epithelial TLR signaling-acting in concert with TLR signaling by leukocytes-participates in the development of intestinal inflammation. We further conclude that the evidence reviewed provides a rationale for the development of novel, epithelial-specific, TLR-based agents in the management of diseases of intestinal inflammation.
Collapse
Affiliation(s)
- Steven C Gribar
- Division of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | | | | |
Collapse
|
39
|
Turner D, Hammerman C, Rudensky B, Schlesinger Y, Wine E, Muise A, Schimmel MS. Low levels of procalcitonin during episodes of necrotizing enterocolitis. Dig Dis Sci 2007; 52:2972-6. [PMID: 17393328 DOI: 10.1007/s10620-007-9763-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Accepted: 01/03/2007] [Indexed: 12/13/2022]
Abstract
The pathogenesis of necrotizing enterocolitis (NEC) remains poorly understood. We aimed to assess the extent of bacterial infection in the pathogenesis of NEC using serial procalcitonin measurements. Blood samples were drawn during the first 4 days following every clinical event requiring a workup for presumed NEC. Eight episodes were confirmed as NEC, 7 of which showed procalcitonin levels <1 ng/ml at presentation and <1.3 ng/ml thereafter, comparable to 24 healthy controls. The one infant with elevated procalcitonin had bacteremia in addition to NEC. Procalcitonin levels of 24 matched septic infants were higher than those of NEC infants, peaking at 4.1 ng/ml. We conclude that low procalcitonin values are the rule during episodes of NEC and provide further evidence that overactive local immune response, and not active infection, is primarily responsible for the mucosal damage in NEC.
Collapse
Affiliation(s)
- Dan Turner
- Department of Pediatrics, Shaare Zedek Medical Center, Jerusalem, Israel.
| | | | | | | | | | | | | |
Collapse
|
40
|
Abstract
Bronchopulmonary dysplasia (BPD) is a common perinatal complication of very low birth weight preterm infants with a significant risk of long-term disability and morbidity. While clinical conditions such as prematurity and mechanical ventilation are its major risk factors, studies suggest that there is an individual susceptibility to BPD. This comprehensive review summarizes data collected about the implication of genetic polymorphisms in BPD and in its risk factors. Some studies have directly related the risk of BPD to genotype. Indeed, carrier states of genetic variants of cytokines (IFNgamma T+874A), adhesion molecules (L-selectin-Pro213Ser), elements of renin-angiotensin system (ACE-I/D), antioxidant enzymes (GST-P1 Val105Ile), and surfactant proteins (SPA1, SPB intron 4) has been identified as risk factors to BPD. Other studies investigated the role of genotype in BPD risk factors. Premature birth has been linked to carrier states of genetic variants with an impact on immune status (such as IL-6 G(-174)C, MBL2 54G/A, VEGF G+405C, HSP72 A+1267G genes) and matrix metalloproteases. Fetal inflammatory response syndrome, a major determinant of BPD is also affected by genotype (including LTalpha A+250G). Disturbed intrauterine lung development and vascularization may also contribute to BPD; these processes may be impaired in the presence of some rare genetic mutations. Furthermore, there is also a genetic component in the susceptibility to other perinatal adaptational disturbances such as respiratory distress syndrome that are associated with an increased need for mechanical ventilation, and, hence, with lung damage. The genetic variants presented in this article may help to identify infants at risk for BPD.
Collapse
Affiliation(s)
- Géza Bokodi
- Ist Department of Pediatrics, Semmelweis University, Budapest, Hungary.
| | | | | | | | | |
Collapse
|
41
|
Duan ZX, Zhu PF, Dong H, Gu W, Yang C, Liu Q, Wang ZG, Jiang JX. Functional significance of the TLR4/11367 polymorphism identified in Chinese Han population. Shock 2007; 28:160-4. [PMID: 17529905 DOI: 10.1097/shk.0b013e31803df782] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Toll-like receptor 4 (TLR4) is the central signaling receptor for lipopolysaccharide (LPS) in mammals. This study was designed to investigate the functional significance of the G11367C polymorphism, which is a novel variant we identified in the 3' untranslated region of TLR4 gene in Chinese Han population. Three hundred seventy healthy volunteers were selected. The TLR4/11367 polymorphism was genotyped using single-tube bidirectional allele-specific amplification method. The TLR4 protein expression on peripheral leukocytes and plasma tumor necrosis factor alpha levels were determined by means of flow cytometry and enzyme-linked immunosorbent assay. The post-transcriptional effect of the 11367 polymorphism was evaluated by means of reporter gene assay and real-time quantitative polymerase chain reaction. The G11367C polymorphism is a common allele in Chinese Han population, with minor allele frequency of 14.7%. In response to ex vivo LPS stimulation, the TLR4 expression on the surface of peripheral leukocytes and the plasma tumor necrosis factor alpha levels were significantly lower in carriers of 11367C variant allele than in carriers of 11367G allele. This association was allele dose dependent. We also found that the activity and the mRNA expression of luciferase was significantly smaller in human embryonic kidney 293 cells transfected with construct containing 11367C allele than in those transfected with construct containing 11367G allele. Together, these results suggest that the TLR4/11367 polymorphism may be a functional single nucleotide polymorphism, which could attenuate the LPS-induced transmembrane signaling through the alteration of post-transcriptional regulation of 3' untranslated region and target gene expression.
Collapse
Affiliation(s)
- Zhao-xia Duan
- State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Daping, Chongqing 400-042, China
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Mohamed MA, Cunningham-Rundles S, Dean CR, Hammad TA, Nesin M. Levels of pro-inflammatory cytokines produced from cord blood in-vitro are pathogen dependent and increased in comparison to adult controls. Cytokine 2007; 39:171-7. [PMID: 17884557 DOI: 10.1016/j.cyto.2007.07.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 06/19/2007] [Accepted: 07/04/2007] [Indexed: 11/16/2022]
Abstract
BACKGROUND Overproduction of pro-inflammatory cytokines may play a role in increased morbidity and mortality from neonatal sepsis. Objective of this study was to compare secretion of pro-inflammatory cytokines by the cord blood cells of healthy term neonates to the venous blood cells of healthy adults in vitro after stimulation with common neonatal pathogens. METHOD Blood samples were cultured in the presence of heat-killed group B beta-hemolytic streptococci (GBS), Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epi). Concentrations of secreted cytokines (interleukine-6, IL-6, tumor necrosis factor-alpha, TNF-alpha, interleukine-1 beta, IL-1beta and interleukine-8, IL-8) were measured after 0, 1, 2 and 4 h of incubation using chemiluminescent immunometric automated assay. RESULTS Blood samples from 22 neonates and 16 adults were compared. After stimulation by GBS and E. coli, cord blood cells secreted significantly higher levels of IL-6 and IL-8 than blood cells of healthy adults. In cord blood, E. coli induced secretion of higher concentration of IL-6, TNF-alpha, IL-1beta and IL-8 than S. epi, and more IL-6 than GBS; GBS induced more IL-1beta than S.epi. CONCLUSIONS Response of cord blood to microbial activators is different from that of adult controls. Each isolate of heat-killed bacteria induced different amount of pro-inflammatory cytokines in vitro. This may represent a useful in vitro virulence test.
Collapse
Affiliation(s)
- Mohamed A Mohamed
- Newborn Services Department, The George Washington University Hospital, Washington, DC 20037-2342, USA.
| | | | | | | | | |
Collapse
|
43
|
Bochud PY, Bochud M, Telenti A, Calandra T. Innate immunogenetics: a tool for exploring new frontiers of host defence. THE LANCET. INFECTIOUS DISEASES 2007; 7:531-42. [PMID: 17646026 PMCID: PMC7185843 DOI: 10.1016/s1473-3099(07)70185-8] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The discovery of innate immune genes, such as those encoding Toll-like receptors (TLRs), nucleotide-binding oligomerisation domain-like receptors (NLRs), and related signal-transducing molecules, has led to a substantial improvement of our understanding of innate immunity. Recent immunogenetic studies have associated polymorphisms of the genes encoding TLRs, NLRs, and key signal-transducing molecules, such as interleukin-1 receptor-associated kinase 4 (IRAK4), with increased susceptibility to, or outcome of, infectious diseases. With the availability of high-throughput genotyping techniques, it is becoming increasingly evident that analyses of genetic polymorphisms of innate immune genes will further improve our knowledge of the host antimicrobial defence response and help in identifying individuals who are at increased risk of life-threatening infections. This is likely to open new perspectives for the development of diagnostic, predictive, and preventive management strategies to combat infectious diseases.
Collapse
|
44
|
Karoly E, Fekete A, Banki NF, Szebeni B, Vannay A, Szabo AJ, Tulassay T, Reusz GS. Heat shock protein 72 (HSPA1B) gene polymorphism and Toll-like receptor (TLR) 4 mutation are associated with increased risk of urinary tract infection in children. Pediatr Res 2007; 61:371-4. [PMID: 17314700 DOI: 10.1203/pdr.0b013e318030d1f4] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Innate immunity and urinary tract response play a central role in the development of urinary tract infection (UTI). Heat shock protein (HSP) 72 and Toll-like receptor (TLR) 4 are among the key elements of innate defence mechanisms. This study assesses the role of HSPA1B A(1267)G and TLR4 A(896)G polymorphisms using allele-specific polymerase chain reaction in 103 patients treated with recurrent UTI. Allelic prevalence was compared with reference values of 235 healthy controls. Clinical data were also statistically evaluated. TLR4 (896)AG genotype and TLR4 (896)G allele had also higher prevalence in UTI patients versus controls (p = 0.031 and 0.041, respectively). Our data indicates a relationship between the carrier status of HSPA1B (1267)G and TLR4 (896)G alleles and the development of recurrent UTI in childhood independently of other renal abnormalities, while raising further questions about the clinical and therapeutic relevance of these polymorphisms in everyday pediatric nephrology.
Collapse
Affiliation(s)
- Eva Karoly
- Hetényi Géza Hospital, Szolnok, H-5004 Hungary
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Abstract
At this moment, few confirmed associations between NOD2 mutations and diseases other than Crohn's disease (CD) and Blau syndrome (BS) have been reported, but research is ongoing in several fields where a genetic susceptibility factor and/or a role for the innate immune system is suspected. Whether the Crohn's-associated CARD15 mutations lead to a loss or gain of function of the NOD2 receptor is subject to controversy, and by which mechanisms this change in function might increase the susceptibility to CD is still under investigation. The possible involvement of NOD2/CARD15 in the pathogenesis of certain diseases with already (partially) unraveled pathophysiologic mechanisms might contribute to our further understanding of NOD2/CARD15 and its function in CD. We review studies on the association of CARD15 variants with diseases other than CD. The association of NOD2/CARD15 mutations with CD and BS, and possibly also early onset sarcoidosis, suggests a role for the gene in the development of granulomata and granulomatous diseases, possibly by inappropriate activation of the immune system. The data from the oncology field suggest that this inappropriate activation might even lead to uncontrolled proliferation of certain cell types. The studies in allergic diseases and atopy are the largest so far, and the association of NOD2/CARDI5 mutations with atopic phenotypes might be an indication that CARD15 also plays a role in the Th2 pathway. Finally, transplantation studies indicate that the genetic background of a patient should be taken into account when considering hematopoietic stem cell transplantation, given the increased risk of mortality and graft versus host disease observed. Whether NOD2 variants are also associated with an increased risk for infections and sepsis in patients receiving immunosuppressive therapies is unclear.
Collapse
|
46
|
Jilling T, Simon D, Lu J, Meng FJ, Li D, Schy R, Thomson RB, Soliman A, Arditi M, Caplan MS. The roles of bacteria and TLR4 in rat and murine models of necrotizing enterocolitis. THE JOURNAL OF IMMUNOLOGY 2006; 177:3273-82. [PMID: 16920968 PMCID: PMC2697969 DOI: 10.4049/jimmunol.177.5.3273] [Citation(s) in RCA: 300] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Bacteria are thought to contribute to the pathogenesis of necrotizing enterocolitis (NEC), but it is unknown whether their interaction with the epithelium can participate in the initiation of mucosal injury or they can act only following translocation across a damaged intestinal barrier. Our aims were to determine whether bacteria and intestinal epithelial TLR4 play roles in a well-established neonatal rat model and a novel neonatal murine model of NEC. Neonatal rats, C57BL/6J, C3HeB/FeJ (TLR4 wild type), and C3H/HeJ (TLR4 mutant) mice were delivered by Cesarean section and were subjected to formula feeding and cold asphyxia stress or were delivered naturally and were mother-fed. NEC incidence was evaluated by histological scoring, and gene expression was quantified using quantitative real-time PCR from cDNA generated from intestinal total RNA or from RNA obtained by laser capture microdissection. Spontaneous feeding catheter colonization or supplementation of cultured bacterial isolates to formula increased the incidence of experimental NEC. During the first 72 h of life, i.e., the time frame of NEC development in this model, intestinal TLR4 mRNA gradually decreases in mother-fed but increases in formula feeding and cold asphyxia stress, correlating with induced inducible NO synthase. TLR4, inducible NO synthase, and inflammatory cytokine induction occurred in the intestinal epithelium but not in the submucosa. NEC incidence was diminished in C3H/HeJ mice, compared with C3HeB/FeJ mice. In summary, bacteria and TLR4 play significant roles in experimental NEC, likely via an interaction of intraluminal bacteria and aberrantly overexpressed TLR4 in enterocytes.
Collapse
Affiliation(s)
- Tamas Jilling
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60614
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Dyan Simon
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60614
| | - Jing Lu
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60614
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Fan Jing Meng
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Dan Li
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Robert Schy
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Richard B. Thomson
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60614
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
| | - Antoine Soliman
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, CA 90048
| | - Moshe Arditi
- Department of Pediatrics, Cedars-Sinai Medical Center, Los Angeles, CA 90048
| | - Michael S. Caplan
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL 60614
- Evanston Northwestern Healthcare Research Institute, Evanston, IL 60201
- Address correspondence and reprint requests to Dr. Michael S. Caplan, Professor of Pediatrics, The Evanston Hospital, 2650 Ridge Avenue, Evanston, IL 60201. E-mail address:
| |
Collapse
|