Association between Tumor Necrosis Factor-α Promoter -308 G/A Polymorphism and Early Onset Sepsis in Preterm Infants

[Recent research on gene polymorphisms and genetic susceptibility of neonatal sepsis]

Neonatal sepsis is a common and severe infectious disease with a high mortality rate. Its pathogenesis is complex, lacks specific manifestations, and has a low positive culture rate, making early diagnosis and personalized treatment still a challenge for clinicians. Epidemiological studies on twins have shown that genetic factors are associated with neonatal sepsis. Gene polymorphisms are closely related to susceptibility, disease development, and prognosis. This article provides a review of gene polymorphisms related to neonatal sepsis, including interleukins, tumor necrosis factor, Toll-like receptors, NOD-like receptors, CD14, triggering receptor expressed on myeloid cells-1, mannose-binding lectin, and other immune proteins, aiming to promote precision medicine for this disease.

A meta-analysis of the association between inflammatory cytokine polymorphism and neonatal sepsis

OBJECTIVE

The purpose of this study is to investigate the relationship between single nucleotide polymorphisms of inflammatory cytokines and neonatal sepsis through meta-analysis.

METHODS

We collected research literature on the correlation between inflammatory cytokine polymorphisms and neonatal sepsis published before August 2023 through computer searches of databases such as PubMed, Embase, etc. The Stata 14.0 software was utilized for Meta-analysis. To assess heterogeneity, the chi-squared Q-test and I2 statistics were used. The Egger and Begg tests were conducted to determine the possibility of publication bias.

RESULTS

After reviewing 1129 articles, 29 relevant articles involving 3348 cases and 5183 controls were included in the study. The meta-analysis conducted on IL-1βrs1143643 polymorphism revealed significant findings: the T allele genotype has a lower risk of neonatal sepsis(P = 0.000, OR = 0.224, 95% CI: 0.168-0.299), while the TC and TT genotypes showed an increased risk(TC: P = 0.000,OR = 4.251, 95% CI: 2.226-8.119; TT: P = 0.019,OR = 2.020, 95% CI: 1.122-3.639). Similarly, newborns with the IL-6-174 CC genotype had a significantly higher risk of sepsis(P = 0.000,OR = 1.591, 95% CI: 1.154-2.194), while those with the IL-8-rs4073 TT (P = 0.003,OR = 0.467, 95% CI: 0.280-0.777)and TT + AA(P = 0.003,OR = 0.497, 95% CI: 0.315-0.785) genotypes had a significantly lower risk of sepsis. For the IL-10-1082 gene, newborns with the AA genotype(P = 0.002,OR = 1.702, 95% CI: 1.218-2.377), as well as those with the AA + GA genotype(P = 0.016,OR = 1.731, 95% CI: 1.108-2.705), had a significantly higher risk of sepsis. Lastly, newborns carrying the TNF-α-308 A allele (P = 0.016,OR = 1.257, 95% CI: 1.044-1.513)or the AA genotype(P = 0.009,OR = 1.913, 95% CI: 1.179-3.10) have a significantly increased risk of sepsis. Notwithstanding, additional studies must be included for validation. Applying these cytokines in clinical practice and integrating them into auxiliary examinations facilitates the early detection of susceptible populations for neonatal sepsis, thereby providing a new diagnostic and therapeutic approach for neonatal sepsis.

Genetic polymorphisms associated with sepsis incidence, severity, and outcomes among neonates: A mini-review

Genetic variation remains a topic of great interest due to its potential as a risk factor for various diseases. Interactions between genes contribute to diverse phenotypes in response to factors such as infection. The impact of genetic background on susceptibility and clinical outcomes, particularly in neonatal sepsis, has gained recognition. The variability in sepsis susceptibility and outcomes can be attributed to the genetic diversity in coding regions and regulatory elements of genes related to innate immune response. Recent advances in genomics and technology have shed light on genetic polymorphisms among humans, often represented by single-nucleotide polymorphisms (SNPs). These SNPs encode proteins crucial for recognizing and responding to pathogenic bacteria, including Toll-like receptor 4, CD14, tumor necrosis factor-alpha, as well as interleukin-1-10. This literature review specifically discusses the involvement of genetic polymorphism during the pathogenesis stage of sepsis, with an emphasis on previous research findings in neonatal sepsis cases, aiming to discuss the implications of polymorphism in sepsis susceptibility and outcomes.

Association between Interleukin-6 rs1800795 Polymorphism and Serum Interleukin-6 Levels and Full-Term Neonatal Sepsis

Objective Cytokines are involved in the pathogenesis of sepsis. Association between IL-6 rs1800795 G/C polymorphism and the risks of sepsis is controversial. The aim of this study was to investigate the association of IL-6 rs1800795 G/C gene polymorphism with full-term neonatal sepsis and to determine its effect on the serum IL6 levels in these infants by a prospective study.

Methods The study included 200 full-term neonates from January 2019 to December 2020: 100 with sepsis (sepsis group), 47 with culture proven sepsis, and 53 with clinical sepsis, and 100 without infection (control group). The concentrations of IL-6 in serum were determined using enzyme-linked immunosorbent assay (ELISA). The polymorphisms of IL-6 rs1800795 G/C were analyzed to compare the genotypic and allelic frequencies in the groups by using the first-generation sequencing (Sanger sequencing). The association was studied between IL-6 rs1800795 G/C polymorphisms and serum IL-6 levels, and neonatal sepsis. The relationships between IL-6 rs1800795G/C polymorphisms and sepsis and serum IL-6 levels were separately analyzed by logistic regression and analysis of variance.

Results There were no significant differences in genotypic frequencies and allelic frequencies of IL-6 rs1800795(G/C) in the groups (p >0.05). There were no relations between IL-6 rs1800795G/C polymorphisms and sepsis and serum IL-6 levels by statistical analysis (p >0.05).

Conclusion IL-6rs1800795G/C may not be genetic risk factors for full-term neonates; There was no association between serum IL-6 levels and IL-6 rs1800795G/C polymorphisms.

Association between innate immunity gene polymorphisms and neonatal sepsis development: a systematic review and meta-analysis

BACKGROUND

The aim of this meta-analysis was to analyze all available data from studies investigating associations between polymorphisms in genes responsible for innate immunity and neonatal sepsis development.

METHODS

A comprehensive literature search, reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-S guidelines, was performed with no language restriction. Studies derived using the PICO (population, intervention, comparison and outcomes) strategy, with data on the genotype distribution for innate immunity gene polymorphisms in newborns with and without sepsis. Data were analyzed using Review Manager. The Cochran-Mantel-Haenszel test was used to calculate odds ratios with 95% confidence intervals. Heterogeneity was tested using the I² index.

RESULTS

From a total of 9428 possibly relevant articles, 33 qualified for inclusion in this systematic review. According to the STrengthening the REporting of Genetic Association Studies, 23 studies were found to be of moderate quality, while 10 were of low quality. The results showed an association of the mannose-binding lectin (MBL) exon 1 genetic polymorphism with the risk of culture-proven sepsis. Toll-like receptor (TLR) 4 rs4986791 genotype distribution suggests its association with the increased risk of culture-proven sepsis. The certainty of evidence per GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) varied from very low to low. Publication bias was not detected.

CONCLUSIONS

Out of the 11 investigated single-nucleotide polymorphisms, this meta-analysis found a possible association between the risk for culture-proven sepsis and MBL exon 1 and TLR4 rs4986791 polymorphisms. There is an evident need for larger well-designed, multicentric observational studies investigating inflammatory gene polymorphisms in neonatal sepsis.

Contemporary Trends in Global Mortality of Sepsis Among Young Infants Less Than 90 Days: A Systematic Review and Meta-Analysis

Objective

Current knowledge on the global burden of infant sepsis is limited to population-level data. We aimed to summarize global case fatality rates (CFRs) of young infants with sepsis, stratified by gross national income (GNI) status and patient-level risk factors.

Methods

We performed a systematic review and meta-analysis on CFRs among young infants < 90 days with sepsis. We searched PubMed, Cochrane Central, Embase, and Web of Science for studies published between January 2010 and September 2019. We obtained pooled CFRs estimates using the random effects model. We performed a univariate analysis at patient-level and a meta-regression to study the associations of gestational age, birth weight, onset of sepsis, GNI, age group and culture-proven sepsis with CFRs.

Results

The search yielded 6314 publications, of which 240 studies (N = 437,796 patients) from 77 countries were included. Of 240 studies, 99 were conducted in high-income countries, 44 in upper-middle-income countries, 82 in lower-middle-income countries, 6 in low-income countries and 9 in multiple income-level countries. Overall pooled CFR was 18% (95% CI, 17-19%). The CFR was highest for low-income countries [25% (95% CI, 7-43%)], followed by lower-middle [25% (95% CI, 7-43%)], upper-middle [21% (95% CI, 18-24%)] and lowest for high-income countries [12% (95% CI, 11-13%)]. Factors associated with high CFRs included prematurity, low birth weight, age less than 28 days, early onset sepsis, hospital acquired infections and sepsis in middle- and low-income countries. Study setting in middle-income countries was an independent predictor of high CFRs. We found a widening disparity in CFRs between countries of different GNI over time.

Conclusion

Young infant sepsis remains a major global health challenge. The widening disparity in young infant sepsis CFRs between GNI groups underscore the need to channel greater resources especially to the lower income regions.

Systematic Review Registration

[www.crd.york.ac.uk/prospero], identifier [CRD42020164321].

Association of IL-6 -174G > C Polymorphism with Susceptibility to Childhood Sepsis: A Systematic Review and Meta-Analysis

BackgroundThis meta-analysis evaluates the correlation between the IL-6 -174 G > C polymorphism and susceptibility of childhood sepsis. Methods: We searched PubMed, ISI Web of Knowledge, Scopus, CNKI, SID, SciELO databases until December 30, 2019 to identify all eligible studies. Results: A total of 17 studies with 1,287 cases and 2,482 controls were identified. Pooled data revealed that there was no significant association between the IL-6 -174 G > C polymorphism and risk childhood sepsis in the overall population. When stratified analysis was carried out by age group of cases, no associations were found in neonates and pediatrics. However, in ethnicity-based subgroups, a significant association was found in Caucasians and Africans. Conclusions: There was no significant association of the IL-6 -174G > C polymorphism with susceptibility to sepsis in childhood overall, but there was an association with the Caucasian and African ethnic subgroups.

Tumor necrosis factor-α small interfering RNA alveolar epithelial cell-targeting nanoparticles reduce lung injury in C57BL/6J mice with sepsis

Background

The role of tumor necrosis factor (TNF)-α small interfering (si)RNA alveolar epithelial cell (AEC)-targeting nanoparticles in lung injury is unclear.

Methods

Sixty C57BL/6J mice with sepsis were divided into normal, control, sham, 25 mg/kg, 50 mg/kg, and 100 mg/kg siRNA AEC-targeting nanoparticles groups (n = 10 per group). The wet:dry lung weight ratio, and hematoxylin and eosin staining, western blotting, and enzyme-linked immunosorbent assays for inflammatory factors were conducted to compare differences among groups.

Results

The wet:dry ratio was significantly lower in control and sham groups than other groups. TNF-α siRNA AEC-targeting nanoparticles significantly reduced the number of eosinophils, with significantly lower numbers in the 50 mg/kg group than in 25 mg/kg and 100 mg/kg groups. The nanoparticles also significantly reduced the expression of TNF-α, B-cell lymphoma-2, caspase 3, interleukin (IL)-1β, and IL-6, with TNF-α expression being significantly lower in the 50 mg/kg group than in 25 mg/kg and 100 mg/kg groups.

Conclusion

TNF-α siRNA AEC-targeting nanoparticles appear to be effective at improving lung injury-related sepsis, and 50 mg/kg may be a preferred dose option for administration.

Genetic variant rs16944 in IL1B gene is a risk factor for early-onset sepsis susceptibility and outcome in preterm infants

OBJECTIVE

Interleukin-1-B (IL1B) is a proinflammatory cytokine that plays an important role in sepsis. The aim of this study was to evaluate the relationships between IL1B-511G/A polymorphism and susceptibility and outcome of early-onset sepsis (EOS) in preterm infants.

METHODS

DNA was extracted from the buccal swabs of 471 (285 with EOS and 186 control) preterm infants. Genotypes of rs16944 polymorphism were determined with real-time PCR method.

RESULTS

We found statistically significant higher frequency of IL1B-511AA genotype in EOS group than in control group (p = 0.012). Also, IL1B-511AA genotype is statistically significantly more frequent in patients with lethal EOS outcome (p = 0.011).

CONCLUSION

Genotype IL1B-511AA was associated with susceptibility to EOS and it is a significant predictor of lethal outcome in preterm infants with EOS.