Unusual haplotypic structure of IL8, a susceptibility locus for a common respiratory virus

Association of the Interleukin 1B-31*C Proinflammatory Allele with the Severity of COVID-19 Patients: A Preliminary Report

Individuals with no known comorbidities or risk factors may develop severe coronavirus disease 2019 (COVID-19). The present study assessed the effect of certain host polymorphisms and viral lineage on the severity of COVID-19 among hospitalized patients with no known comorbidities in Mexico. The analysis included 117 unrelated hospitalized patients with COVID-19. Patients were stratified by whether they required intensive care unit (ICU) admission: the ICU group (n = 40) and non-ICU group (n = 77). COVID-19 was diagnosed on the basis of a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription-polymerase chain reaction (RT-PCR) assay and clinical and radiographic criteria. The presence of the IL1B-31 (T/C) polymorphism was determined for all patients using PCR and nucleotide sequencing. Genotyping of the IL-4 (-590, T/C) and IL-8 (-251, T/A) polymorphisms was performed by the amplification refractory mutation system-PCR method. Genotyping of IL1-RN was performed using PCR. Viral genome sequencing was performed using the ARTIC Network amplicon sequencing protocol using a MinION. Logistic regression analysis identified the carriage of IL-1 B*-31 *C as an independent potential risk factor (odds ratio [OR] = 3.1736, 95% confidence interval [CI] = 1.0748-9.3705, p = 0.0366) for ICU admission and the presence of IL-RN*2 as a protective factor (OR = 0.4371, 95% CI = 0.1935-0.9871, p = 0.0465) against ICU admission. Under the codominant model, the CC genotype of IL1B-31 significantly increased the risk of ICU admission (OR: 6.38, 95% CI: 11.57-25.86, p < 0.024). The IL1B-31 *C-IL-4-590 *T haplotype increased the risk of ICU admission (OR = 2.53, 95% CI = 1.02-6.25, p = 0.047). The 42 SARS-CoV-2 genomes sequenced belonged to four clades, 20A-20D. No association was detected between SARS-CoV-2 clades and ICU admission or death. Thus, in patients with no known comorbidities or risk factors, the IL1B-31*C proinflammatory allele was observed to be associated with the risk of ICU admission owing to COVID-19.

Identification of immune-related mechanisms of cetuximab induced skin toxicity in colorectal cancer patients

Skin rash is a well-known predictive marker of the response to cetuximab (Cmab) in metastatic colorectal cancer (mCRC). However, the mechanism of skin rash development is not well understood. Following exposure to EGFR-targeted therapies, changes in IL-8 levels have been reported. The aim of this study was to evaluate the association between skin rash and inflammatory cytokine levels, including IL-8. Between 2014 and 2017, we prospectively enrolled 38 mCRC patients who underwent chemotherapy with either Cmab or bevacizumab (Bmab) at two hospitals. We performed multiplex cytokine ELISA with 20 inflammatory cytokines including E-selectin, GM-CSF, IFN-alpha, IFN-γ, IL-1 alpha, IL-1 beta, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17A, IP-10, MCP-1, MIP-1 alpha, MIP-1 beta, P-selectin, sICAM-1, and TNF-alpha at baseline before cycle 1, 24 h after cycle 1, before cycle 2 (= 14 d), and before cycle 3 (= 28 d). Cytokine levels were compared using ANOVA after log-transformation. IL-8 genotypes in 30 patients treated with Cmab were determined using the polymerase chain reaction restriction fragment length polymorphism technique. Depending on the RAS mutational status, 30 and eight patients were treated with Cmab and Bmab-based chemotherapy, respectively. Skin rash developed in 23 (76.6%) of the 30 patients treated with Cmab plus FOLFIRI, after cycle 1. Only the mean log-transformed serum IL-8 level in patients with skin toxicity was statistically lower (2.83 ± 0.15) than in patients who did not experience skin toxicity (3.65 ± 0.27) and received Bmab (3.10 ± 0.26) (ANOVA test, p value = 0.0341). In addition, IL-8 polymorphism did not affect IL-8 levels, skin toxicity, or tumor response in Cmab treated patients. This study suggests that the inflammatory cytokine levels might be affected by Cmab exposure and are associated with the development of skin rash in mCRC patients. Further studies are warranted to evaluate this interaction in Cmab treated patients.

Association of Interleukin 6 and Interleukin 8 genes polymorphisms with house dust mite-induced nasal-bronchial allergy in a sample of Indian patients

Background

Genetic background of nasal-bronchial allergy (NBA) is well documented. House Dust Mites (HDMs) are reported to elicit NBA symptoms. Susceptibility to HDM sensitization varies considerably from person to person. Interleukin 6 (IL 6) and Interleukin 8 (IL 8) are studied previously for genetic association with several diseases. To the best of our knowledge, the genetic association of HDM-induced NBA has not been largely reported from India. The aim of our present study was to evaluate any possible association of IL 6 and IL 8 gene polymorphisms with HDM-induced NBA in an Indian population.

Methods

IL 6 (− 572G/C, − 597G/A) and IL 8 polymorphisms (− 251A/T, + 781C/T) were analyzed in a HDM-sensitized group (N = 372) and a control group (N = 110). Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR–RFLP) based genotyping was done. Chi-square test and Fisher’s exact tests were applied for statistical analysis.

Results

IL 6 − 597G/A and IL 8 + 781C/T were not associated with HDM-sensitization, while IL 6 − 72G/C and IL 8 − 51A/T showed significant associations in terms of both genotype and allele frequencies. For both the SNPs, minor allele frequencies were significantly higher in the patients compared to the control. Moreover, IL 6 -572G/C and IL 8 -251A/T were found to be strongly linked with HDM sensitization and severity.

Conclusion

This is probably the pioneer study to describe the association of IL 6 and IL 8 polymorphisms with HDM sensitization in any Indian population. The results suggested that IL 6 -572G/C and IL 8 -251A/T may exert a risk of HDM sensitization leading to NBA.

Effect of IL8 haplotype on immunological traits in periparturient dairy cows

Interleukin 8 (IL8) is a major mediator of the innate immune response. Polymorphisms in this gene are associated with susceptibility to inflammatory disease in humans. Two major promoter polymorphic haplotypes (IL8-h1 and IL8-h2) segregating in cattle populations have shown a significant effect on the immune response profile in calves but their implications for transition cow immunity have not been established. The aims of this study were to assess functional relevance of the IL8 haplotypes on the immunological traits of periparturient cows (n = 32) belonging to three genetic groups: Holstein (HO), Simmental (SI) and their crosses (CR) and to evaluate the frequency of IL8 haplotypes in the HO (dairy) and SI (dual purpose) pure breeds. IL8 haplotypes showed a significant effect on circulating number of both T helper lymphocytes (P = 0.0133) and T cytotoxic lymphocytes (P = 0.0024). Differences in percentage of CD14⁺ monocytes and T lymphocyte subsets were found between haplotype groups at different time points. Plasma concentrations of Serum Amyloid A (SAA) and Haptoglobin (Hp) were enhanced at calving in IL8-h2 (P = 0.0019, P = 0.0029) and IL8-het (P = 0.050 and P = 0.052) respectively, compared with IL8-h1 cows. In contrast, significantly lower levels of reactive oxygen metabolites (d-ROMs) activation were identified in IL8-h2 and IL8-het cows after calving compared with IL8-h1 cows. Furthermore, genotyping results showed that SI cows have a high frequency of the homozygous IL8-h2 haplotype compared to the HO cows (87.5 % vs 40 %) which reflects the different selective pressure between the two pure breeds. In conclusion, our preliminary data suggests that IL8 promoter haplotype is associated with significant and dynamic changes in immunological traits during peripartum and early lactation period. Future work will focus on a more comprehensive assessment of immune changes in additional cows.

Polymorphisms of Interleukin-6 and Interleukin-8 Are Not Associated with Parkinson's Disease in Taiwan

Background: Studies have suggested that cytokines are crucial mediators in the pathogenesis of Parkinson’s disease (PD). The multifunctional cytokine interleukin (IL)-6 and its single nucleotide polymorphisms (SNPs) were found to have an impact on the development of PD. However, different studies in associations of IL-6 genetic variants with PD showed inconsistent results and it has never been explored in a Taiwanese population. Both IL-1α and IL-8 contribute to the same inflammation pathway. IL-1α genetic polymorphism has an effect on late-onset PD in Taiwan, whereas the associations of IL-8 genetic variants with PD in Taiwan remain to be investigated. Methods: This study examined the frequencies of polymorphisms within the critical promoter areas of the proinflammatory cytokine genes: IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) in Taiwanese PD patients compared with age-and gender-matched healthy subjects. Comparisons were also made in genotype and allele frequencies of IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) among different populations in previous studies. Results: In total, 1120 subjects, including 509 PD patients (female/male: 259/250) and 511 control subjects (female/male: 252/259), were recruited. We found no statistically significant differences in IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) genotypic and allelic distribution between PD and controls, even after being stratified by age at onset and gender. Conclusions: The results did not demonstrate any association of IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) with PD in a Taiwanese population. Despite the negative results, this is the first study in associations of IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) with PD in Taiwan. The relevance of genetic variants of IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) on PD susceptibility warrants further investigation.

The Relationship Between Chemokine and Chemokine Receptor Genes Polymorphisms and Chronic Obstructive Pulmonary Disease Susceptibility in Tatar Population from Russia: A Case Control Study

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease affecting primarily distal respiratory pathways and lung parenchyma. This study aimed to determine possible genetic association of chemokine and chemokine receptor genes polymorphisms with COPD in a Tatar population from Russia. SNPs of CCL20, CCR6, CXCL8, CXCR1, CXCR2, CCL8, CCL23, CCR2, and CX3CL1 genes and their gene-gene interactions were analyzed for association with COPD in cohort of 601 patients and 617 controls. As a result statistically significant associations with COPD in the study group under the biologically plausible assumption of additive genetic model were identified in CCL20 (rs6749704) (P = 0.00001, OR 1.55), CCR6 (rs3093024) (P = 0.0003, OR 0.74), CCL8 (rs3138035) (P = 0.0001, OR 0.67), CX3CL1 (rs170364) (P = 0.023, OR 1.21), CXCL8 (rs4073) (P = 0.007, OR 1.23), CXCR2 (rs2230054) (P = 0.0002, OR 1.32). Following SNPs CCL20 (rs6749704), CX3CL1 (rs170364), CCL8 (rs3138035), CXCL8 (rs4073), CXCR2 (rs2230054) showed statistically significant association with COPD only in smokers. The association of CCR6 (rs3093024) with COPD was confirmed both in smokers and in non-smokers. A relationship between smoking index and CCL20 (rs6749704) (P = 0.04), CCR6 (rs3093024) (P = 0.007), CCL8 (rs3138035) (P = 0.0043), and CX3CL1 (rs170364) (P = 0.04) was revealed. A significant genotype-dependent variation of Forced Vital Capacity was observed for CCL23 (rs854655) (P = 0.04). Forced Expiratory Volume in 1 s / Forced Vital Capacity ratio was affected by CCL23 (rs854655) (P = 0.05) and CXCR2 (rs1126579) (P = 0.02). Using the APSampler algorithm, we obtained nine gene-gene combinations that remained significantly associated with COPD; loci CCR2 (rs1799864) and CCL8 (rs3138035) were involved in the largest number of the combinations. Our results indicate that CCL20 (rs6749704), CCR6 (rs3093024), CCR2 (rs1799864), CCL8 (rs3138035), CXCL8 (rs4073), CXCR1 (rs2234671), CXCR2 (rs2230054), and CX3CL1 (rs170364) polymorphisms are strongly associated with COPD in Tatar population from Russia, alone and in combinations. For the first time combination of the corresponding SNPs were considered and as a result 8 SNP patterns were associated with increased risk of COPD.

The association between interleukin-8 gene-251 A/T polymorphism and sepsis: A protocol for systematic review and meta analysis

BACKGROUND

Emerging evidence has indicated that interleukin-8 (IL-8) gene-251A/T polymorphism may affect individual susceptibility to sepsis. However, the results of published studies are inconclusive. The aim of this meta-analysis was to elucidate the association between this polymorphism and the risk and mortality of sepsis.

METHODS

Relevant publications were searched from PubMed, EmBase, and Web of Science databases up to January 31, 2021, with studies only in English. The reference lists of the retrieved studies were investigated as well. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to figure out the relationship between IL-8-251 A/T polymorphisms and the risk and mortality of sepsis. All of the data were analyzed with Stata 16.0.

RESULTS

The results of this meta-analysis will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This meta-analysis will summarize the relationship between IL-8-251 A/T polymorphism and the risk and mortality of sepsis.

Interleukin-8 genetic diversity, haplotype structure and production differ in two ethnically distinct South African populations

A single nucleotide polymorphism (SNP), 251 bases upstream from the IL-8 transcription start (-251A>T, rs4073), has been extensively investigated in cancers and inflammatory and infectious diseases in predominantly European and Asian populations. We sequenced the IL-8 gene of 109 black and 32 white South African (SA) individuals and conducted detailed characterization of gene variation and haplotype structure. IL-8 production in phytohaemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMCs) of a subset (black: N = 22; white: N = 32) of these individuals was measured using ELISA. Select variants were genotyped for additional black individuals (N = 141), and data from the 1000 Genomes Project were used for haplotype analysis and comparative purposes. In white individuals, the -251A>T SNP formed part of a prevalent six-variant haplotype [haplotype frequency (HF): 61%], Hap-1C, involving the following variants: -251A>T; +394T>G (rs2227307); +780C>T (rs2227306); +1240->A (rs2227541); +1635C>T (rs2227543) and +2770A>T (rs2227543). Hap-1C (-251T+394T+780C+1240+A+1635C+2770A) was composed of two three-variant sub-haplotypes [Hap-1Ca: -251T+394T+1240+A; Hap-1Cb: +780C+1635C+2770A) sharing similarities with haplotypes identified in the black population. Hap-1C was found to be present in European, East and South Asian populations. Four haplotypes were identified in the black population with the two prevalent haplotypes each comprised of two variants: Hap-1B [-251A>T and +1240->A; -251T+1240+A; HF: 14%] and Hap-2B [-743T>C (rs2227532) and +2452A>C (rs2227545); -743C+2452C; HF: 13%]. Populations did not differ in unstimulated PBMC IL-8 production. Upon PHA stimulation, PBMCs from white individuals produced more IL-8 (P = 0.04), suggesting the -251T allele is responsible for higher production, however further analysis revealed that Hap-1C (and constituent sub-haplotypes), did not associate with IL-8 production. Populations did however differ in monocyte number with the white population having significantly more monocytes compared to the black population (P = 0.025), and furthermore monocyte number strongly correlated with IL-8 production in both population groups (black: p = 0.0002, r = 0.71; white: P = 0.0005, r = 0.59). Hap-1B, Hap-2B, and a SNP located one base pair upstream of the IL-8 ATG start codon, +100C>T SNP (rs2227538), all associated with higher IL-8 production in the black population - individuals harbouring at least one of these haplotypes/variant associated with higher IL-8 production (P = 0.003) compared to individuals without. The black population was enriched for individuals harbouring Hap-1B and/or Hap-2B compared to the 1000 Genomes project sub-Saharan African population (P = 0.006), suggesting that SA black individuals may be high IL-8 producers. Given the paucity of IL-8-related studies that have been conducted in populations from sub-Saharan Africa, this study has significantly increased our understanding of this important chemokine in the South African population.

The transcriptomic profiling of SARS-CoV-2 compared to SARS, MERS, EBOV, and H1N1

The SARS-CoV-2 (COVID-19) pandemic is a global crisis that threatens our way of life. As of November 18, 2020, SARS-CoV-2 has claimed more than 1,342,709 lives, with a global mortality rate of ~2.4% and a recovery rate of ~69.6%. Understanding the interaction of cellular targets with the SARS-CoV-2 infection is crucial for therapeutic development. Therefore, the aim of this study was to perform a comparative analysis of transcriptomic signatures of infection of SARS-CoV-2 compared to other respiratory viruses (EBOV, H1N1, MERS-CoV, and SARS-CoV), to determine a unique anti-SARS-CoV-2 gene signature. We identified for the first time that molecular pathways for heparin-binding, RAGE, miRNA, and PLA2 inhibitors were associated with SARS-CoV-2 infection. The NRCAM and SAA2 genes, which are involved in severe inflammatory responses, and the FGF1 and FOXO1 genes, which are associated with immune regulation, were found to be associated with the cellular gene response to SARS-CoV-2 infection. Moreover, several cytokines, most significantly IL-8 and IL-6, demonstrated key associations with SARS-CoV-2 infection. Interestingly, the only response gene that was shared among the five viral infections was SERPINB1. The protein-protein interaction (PPI) analysis shed light on genes with high interaction activity that SARS-CoV-2 shares with other viral infections. The findings showed that the genetic pathways associated with rheumatoid arthritis, the AGE-RAGE signaling system, malaria, hepatitis B, and influenza A were of high significance. We found that the virogenomic transcriptome of infection, gene modulation of host antiviral responses, and GO terms of SARS-CoV-2 and EBOV were more similar than to SARS, H1N1, and MERS. This work compares the virogenomic signatures of highly pathogenic viruses and provides valid targets for potential therapy against SARS-CoV-2.

Correlation between female sex, IL28B genotype, and the clinical severity of bronchiolitis in pediatric patients

BACKGROUND

Single-nucleotide polymorphisms (SNPs) that impact on the differential expression of interleukin 28B (IL28B) are implicated in the progression of viral-induced diseases. In this prospective longitudinal cohort study, we evaluated the association between IL28B SNPs rs12979860 and rs8099917 and the clinical outcome of bronchiolitis in pediatric patients.

METHODS

A total of 682 infants suffering from bronchiolitis, categorized based on the final clinical outcome as mild or severe, were genotyped for IL28B SNPs rs12979860 and rs8099917.

RESULTS

When infants were categorized exclusively based on the final clinical outcome, no association was established between IL28B SNPs and the severity of bronchiolitis. However, when stratified by sex, the homozygotes for the minor alleles of rs12979860 (T) and rs8099917 (G) were associated with a mild disease in girls but not in boys.

CONCLUSION

SNPs rs12979860 and rs8099917 correlate with the severity of bronchiolitis and display a sex bias, where GG rs8099917 and TT rs12979860 genotypes are associated with a mild disease in girls but not in boys. These findings suggest that innate immunity and female sex links with the outcome of the diseases induced by respiratory viruses, such as RSV.

Interleukin-8 Gene -251 A/T (rs4073) Polymorphism and Coronary Artery Disease Risk: A Meta-Analysis

BACKGROUND Inflammation plays an important role in the pathogenesis of coronary artery disease (CAD). Studies have reported that inflammatory cytokine interleukin-8 (IL-8) gene -251 A/T (rs4073) polymorphism is correlated with CAD susceptibility, but the result remains controversial. The objective of this study was to clarify the association between IL-8 gene -251 A/T polymorphism and CAD risk. MATERIAL AND METHODS A meta-analysis included 8244 patients from 9 individual studies with 10 populations was conducted. Heterogeneity test was conducted, and pooled odds ratio (OR) with 95% confidence interval (CI) was calculated used fixed-effect or random-effects model accordingly. Publication bias was evaluated with the Begg's funnel plot and Egger's test. Sensitivity analysis was also conducted. RESULTS A significant association between IL-8 gene -251 A/T polymorphism and CAD risk was found in the dominant model (OR 1.42, 95% CI 1.16-1.76, P<0.001), recessive model (OR 1.30, 95% CI 1.12-1.52, P<0.001), allelic model (OR 1.28, 95% CI 1.12-1.47, P<0.001), homozygote model (OR 1.59, 95% CI 1.21-2.08, P<0.001), and heterozygote model (OR 1.35, 95% CI 1.11-1.64, P=0.002). Subgroup analysis by ethnicity found significant associations in the Chinese population in the dominant model(OR 1.43, 95% CI 1.26-1.61, P<0.001), recessive model (OR 1.39, 95% CI 1.21-1.59, P<0.001), allelic model (OR 1.31, 95% CI 1.21-1.42, P<0.001), homozygote model (OR 1.66, 95% CI 1.41-1.95, P<0.001), and heterozygote model (OR 1.34, 95% CI 1.18-1.52, P<0.001), but no significant association was found in the Caucasian population. No significant publication bias was found. CONCLUSIONS The IL-8 gene -251 A/T polymorphism was significantly associated with CAD risk in the Chinese population but not in the Caucasian population, -251 A allele carrier had an increased risk of CAD in the Chinese population.

IL-8 Gene Variants and Expression in Childhood Asthma

PURPOSE

To examine the IL-8 expression levels and association of genetic variants with the risk of childhood persistent asthma prognosis.

METHODS

Overall, 170 asthmatic children and 170 healthy controls were included in this case-control study. The human IL-8 serum levels were measured using ELISA. The IL-8 mRNA expression levels were assessed by a real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods.

RESULTS

The IL-8 expression at both protein and mRNA levels was found to be significantly elevated in asthmatic children compared to healthy subjects (P < 0.0001, P = 0.004; respectively). Higher levels of IL-8 mRNA are detected in subjects with moderate to severe asthma. The presence of IL8-251 A/T (rs4073) and + 781C/T (rs2227306) polymorphisms was significantly associated with an increased risk of asthma (P = 0.002, P = 0.036, respectively). In addition, we noted a significant association between these polymorphisms and an elevated risk of atopic asthma (P < 0.05). For rs2227306 SNP, the highest median level of IgE was detected for the presence of TT genotype (865 ± 99.74 IU/mL). Although, the rs4073 polymorphism conferred a higher risk to develop asthma at an advanced stage of severity (P = 0.008). The rs4073 T and rs2227306 C alleles are considered as risk factors for asthma development. The rs4073 T allele is represented also as a risk factor for asthma severity in Tunisian children.

CONCLUSIONS

Both IL-8 gene and protein expression may play a key role in asthma pathogenesis.

Genetic parameters estimated at receiving for circulating cortisol, immunoglobulin G, interleukin 8, and incidence of bovine respiratory disease in feedlot beef steers

Bovine respiratory disease complex (i.e., shipping fever and bacterial bronchopneumonia) is a multifaceted respiratory illness influenced by numerous environmental factors and microorganisms. Bovine respiratory disease (BRD) is just one component of BRD complex. Because BRD is moderately heritable, it may be possible to reduce the incidence of BRD through genetic selection. The objectives of this study were to determine the heritability and associative genetic relationships among immune system traits (i.e., cortisol, total IgG, IgG isotypes, and IL-8) in cattle monitored for BRD incidence. At an average of 83 d after weaning (219 d age and mean = 221.7 kg [SD 4.34]), crossbred Bos taurus steer calves (n = 2,869) were received at a commercial feedlot in southeastern Colorado over a 2-yr period. At receiving, jugular blood samples were collected at 212 (yr 1) and 226 d (yr 2) of age for immune trait analyses. The BRD phenotype was defined as a binomial variable (0 = no and 1 = yes) and compared with immune system traits measured at receiving (prior to illness onset). An animal identified as BRD positive exhibited ≥ 2 clinical signs (i.e., eye or nasal discharge, cough, lethargy, rapid breathing, acute interstitial pneumonia, or acute upper respiratory syndrome and/or a rectal temperature > 39.7°C). Heritability and genetic correlation estimates for categorical variable BRD, cortisol, IgG, IgG1, IgG2, and IL-8 were estimated from a sire model using ASREML. Heritability estimates were low to moderate for BRD (0.17 ± 0.08), cortisol (0.13 ± 0.05), IgG (0.15 ± 0.05), IgG1 (0.11 ± 0.05), IgG2 (0.24 ± 0.06), and IL-8 (0.30 ± 0.06). A moderate negative genetic correlation was determined between BRD and cortisol (r_g = −0.19 ± 0.32). Moderate positive correlations were found between BRD with IgG (0.42 ± 0.28), IgG1 (0.36 ± 0.32), and IL-8 (r_g = 0.26 ± 0.26). Variation in the BRD phenotype and immune system traits suggested herd health improvement may be achieved through genetic selection.

Interleukin 8 (-251 T>A) polymorphism in children and teenagers infected with Helicobacter pylori

Background

Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the human stomach and causes a variety of gastric diseases. This study evaluated the correlations between the -251 (T>A) (rs4073) polymorphism of interleukin-8 (IL-8), the etiology of gastric disease, and H. pylori infection in pediatric and adolescent patients.

Methods

DNA samples were obtained from 285 gastric biopsies from pediatric patients. H. pylori was detected by PCR, whereas PCR-RFLP was used to characterize the -251 (T>A) polymorphism of IL-8.

Results

The histological analysis revealed the presence of gastritis in 158 patients (55.44%). H. pylori was found in 71 samples (24.9%). The -251 (T>A) polymorphism revealed that 58 (29.47%) samples were TT, 143 (50.18%) samples were TA, and 84 (20.35%) samples were AA.

Conclusions

Our findings suggest that IL8-251 A allele may be an important risk factor for the development of gastric disease when associated with H. pylori infection.

The gene polymorphisms of IL-8(-251T/A) and IP-10(-1596C/T) are associated with susceptibility and progression of type 2 diabetic retinopathy in northern Chinese population

PurposeThe aim of the present study is to investigate the association of the polymorphism of two genes in CXC chemokine family, interleukin-8 (IL-8) and interferon-inducible protein 10 (IP-10), with both susceptibility and progression of DR in T2D population of northern China.Patients and methodsA total of 1043 eligible type 2 diabetic patients from Heilongjiang of northern China were recruited for this study. They were grouped into: with diabetic retinopathy (DR, 528 cases) and without diabetic retinopathy (DNR, 515 cases). Single nucleotide polymorphism (SNP) genotyping of IL-8(-251T/A) and IP-10(-1596C/T) was performed by polymerase chain reaction. Multivariate analysis and stepwise multiple logistic progression analysis were conducted to evaluate the association between gene SNP and DR susceptibility and progression. Pooled odds ratio (OR) with 95% confidence interval (CI) was applied to assess the strength of the association among study groups.ResultsThe occurring of IL-8(-251) AA genotype was correlated with susceptibility (OR: 2.286, 95% CI: 1.382-3.782, P=0.001) and progression of high-risk proliferative diabetic retinopathy (PDR) (OR: 0.354, 95% CI: 0.162-0.770, P=0.009). Reversely, T allele of IP-10 (-1596) C/T was correlated with a reduced risk of DR (OR: 0.341, 95% CI: 0.249-0.466, P<0.001). However, gene polymorphisms of IL-8-251T/A and IP-10-1596C/T were not associated with diabetic macular edema (DME)(P>0.05).ConclusionsAA genotype of IL-8-251T/A was closely correlated to DR and high-risk proliferative diabetic retinopathy (PDR). -1596T allele of the IP-10 is a beneficial genotype for DR.

Influence of IL-6, IL-8, and TGF-β1 gene polymorphisms on the risk of human papillomavirus-infection in women from Pernambuco, Brazil

Human papillomavirus (HPV) infections are strongly associated with the development of cervical intraepithelial neoplasias and invasive cervical cancer. Polymorphisms in cytokine-encoding genes and behavioural cofactors could play an important role in protecting an individual against viral infections and cancer. Here, we investigated whether IL-6 -174 G>C, IL-8 +396 G>T, and TGF-β1 +869 G>C and +915 G>C polymorphisms were associated with susceptibility to HPV infection in women from north-east (Pernambuco) Brazil. We analysed 108 healthy uninfected women (HC) and 108 HPV-positive women with cervical lesions. Genetic polymorphisms were assessed using Sanger sequencing and polymerase chain reaction-restriction fragment length polymorphism. Comparison of the distribution of the genotypic and allelic frequencies of the IL-18 +396 T>G polymorphism between HPV infected woman an uninfected controls showed that the GG genotype and G allele were both more frequent in the HC group, and were associated with protection from HPV infection (p = 0.0015; OR = 0.29 CI95% = 0.13-0.61; p = 0.0005; OR = 0.45 CI95% 0.29-0.7, respectively). Individuals from the control group could have previously had HPV infection that was spontaneously eliminated; however, it was undetectable at the time of sample collection. Based on our findings, we hypothesize that the IL-8 +396 G>T polymorphism could interfere with susceptibility to HPV infection, by modulating the ability of immune system to fight the virus.

An investigation of polymorphisms in the 4q13.3-21.1 CXC chemokine gene cluster for association with multiple sclerosis in Australians

Susceptibility to multiple sclerosis (MS) is believed to result from the complex interaction of a number of genes, each with modest effect. Vital to the migration of cells to sites of inflammation, including the central nervous system, are chemokines, many of which are implicated in MS pathogenesis. Most of the CXC chemokine genes are encoded in a cluster on chromosome 4q13.3-21.1, which has been identified in several genome-wide screens as being potentially associated with MS. We conducted a two-stage analysis to investigate the chemokine gene cluster for association with MS. Initially, we sequenced the chemokine genes in several DNA pools to identify common polymorphisms, and then genotyped selected SNPs in 373 Australian MS trio families. We found no evidence that the CXC chemokine gene cluster is genetically associated with MS. However, the existence of common variants conferring small risk factors or rare variants with significant risk cannot be excluded.

IL8 gene as modifier of cystic fibrosis: unraveling the factors which influence clinical variability

The severity of cystic fibrosis (CF) is associated with classes of mutations in the CFTR gene (cystic fibrosis transmembrane regulator), physical environment and modifier genes interaction. The IL8 gene (interleukin 8), according to its respective polymorphisms, influences inflammatory responses. This study analyzed IL8 gene polymorphisms (rs4073, rs2227306 and rs2227307), by means of PCR/RFLP, and their association with pulmonary function markers and clinical severity scores in 186 patients with CF, considering the CFTR genotype. There was an association between rs2227307 and precocity of the disease. The severity of lung disease was associated with the following markers: transcutaneous arterial hemoglobin oxygen saturation (SaO2) (regardless of CFTR genotype, for the polymorphisms rs4073, rs2227306 and rs2227307); mucoid Pseudomonas aeruginosa (regardless of CFTR genotype, for the polymorphisms rs2227306 and rs2227307). Pulmonary function markers (SaO2 and spirometric variables) and clinical severity scores were also associated with IL8 gene polymorphisms. This study identified the IL8 gene, represented by rs4073 and rs2227306 polymorphisms, and particularly the rs2227307 polymorphism, as potentiating factors for the degree of variability in the severity of CF, especially in pulmonary clinical manifestation correlated with increased morbidity and mortality.

The IL-8 Gene Polymorphisms in Behçet's Disease Observed in Denizli Province of Turkey

Behçet's disease is a multisystemic inflammatory disorder as a triad of symptoms including recurrent oral and genital aphthous ulceration and uveitis with unknown pathogenesis. IL-8, a proinflammatory cytokine, has been found increased in the active stage of BD. DNA samples were obtained from 88 patients with BD and 112 healthy control subjects in Denizli province of Turkey. All genotyping experiments of SNPs in IL-8 gene were performed using polymerase chain reaction-restriction fragment polymorphism. We found that IL-8 -845 T > C and -738 T > A sites are non-polymorphic. There were no differences in the polymorphisms of IL-8 +396 G/T, +781 C/T, and +1633 C/T sites except IL-8 -251 T > A in between patients and healthy controls. Analysis of IL-8 polymorphisms indicates that the distribution of frequencies seems to be associated with -251 T > A and gender, -251 T > A and erythema nodosum, -251 T > A and ocular involvement, +781 C > T and erythema nodosum, +396 G > T and pathergy positivity, and +1633 C > T and papulopustular lesion. We demonstrated that the frequencies of IL-8 haplotypes were significantly different with BD patients than control group. We found that the distribution of IL-8 haplotypes was significantly different with genital ulcers, ocular involvement, positive pathergy test, erythema nodosum, papulopustular lesions, and arthritis with BD patients than healthy control individuals. Our study suggests that IL-8 gene polymorphisms may affect susceptibility to BD and increase the risk of developing disease. In order to confirm and assess the association of IL-8 and other cytokine gene polymorphisms in the pathophysiology of BD, large cohort studies are needed.

The genetic variant rs4073 A→T of the Interleukin-8 promoter region is associated with the earlier onset of exudative age-related macular degeneration

Purpose

To study the association of the single nucleotide polymorphism (SNP) rs4073 in the interleukin‐8 (IL‐8) promoter region with the diagnosis and age of onset of exudative age‐related macular degeneration (AMD) in association with the known genetic risk factors for AMD and tobacco smoking.

Methods

Medical records, smoking history and angiograms or fundus photographs of 301 patients with exudative AMD, 72 patients with dry AMD and 119 control subjects were analysed retrospectively. The associations of IL‐8 rs4073 A→T, CFH rs1061170 T→C, ARMS2 rs10490924 G→T and C3 rs2230199 C→G SNPs with the presence of AMD and with the age of onset of exudative AMD were analysed.

Results

Younger age of exudative AMD onset was associated with the homozygous AA genotype of IL‐8 rs4073 (p = 0.009, Mann–Whitney U‐test), CC genotype of CFH rs1061170 (p = 0.016), TT genotype of ARMS2 rs10490924 (p = 0.001) and with current smoking (p = 0.002). The risk alleles C in CFH rs1061170 (p < 0.0001, Pearson chi‐square) and T in ARMS2 rs10490924 (p < 0.0001), as well as smoking (p < 0.0001), were more prevalent in AMD patients compared with controls. No association was found between the IL‐8 rs4073 genotype and the presence of AMD.

Conclusion

Out of the factors associated with the earlier onset of exudative AMD, only the genotype of IL‐8 rs4073 did not appear as a risk factor for AMD in general. IL‐8 may have a role in accelerating the development of the choroidal neovascularization in exudative AMD.

Association between interleukin 8 -251 A/T and +781 C/T polymorphisms and osteosarcoma risk in Chinese population: a case-control study

Interleukin-8 (IL-8) is an angiogenic chemokine that plays a potent role in both development and progression of many human malignancies. However, there are no data about the role of IL-8 polymorphism in development of osteosarcoma. A hospital-based case-control study was conducted among 190 patients with osteosarcoma and 190 healthy controls to investigate the possible association between the IL-8 -251 A/T and +781 C/T polymorphisms, respectively, and the risk of osteosarcoma. Significant differences of genotype distribution were observed between osteosarcoma cases and controls at the IL-8 -251T/A genotypes. Compared with the IL-8 -251T/A homozygote TT, the heterozygous TA genotype was associated with significantly increased risk for osteosarcoma (odds ratio (OR) = 2.16, 95 % confidence interval (CI) = (1.38-4.52), P = 0.021); the AA genotype was associated with increased risk for osteosarcoma (OR = 1.94, 95 % CI = 1.31-3.83, P = 0.018). TA and AA combined variants were associated with increased risk for osteosarcoma compared with the TT genotype (OR = 1.72, 95 % CI = 1.45-4.41, P = 0.023). Moreover, the genotype AA of IL-8 -251T/A carried a higher risk of osteosarcoma metastasis and later Enneking stages, compared with the TT genotype. However, the genotype and allele frequencies of IL-8 +781 C/T polymorphisms in osteosarcoma patients were not significantly different from controls. Our results showed that the IL-8 -251 A/T genotype was associated with increased risk for development and metastasis of osteosarcoma in Chinese Han population.

Genes associated with RSV lower respiratory tract infection and asthma: the application of genetic epidemiological methods to understand causality

Infants with respiratory syncytial virus (RSV) lower respiratory tract infections (LRIs) are at increased risk for childhood asthma. The objectives of this article are to review the genes associated with both RSV LRI and asthma, review analytic approaches to assessing shared genetic risk and propose a future perspective on how these approaches can help us to understand the role of infant RSV infection as both an important risk factor for asthma and marker of shared genetic etiology between the two conditions. The review of shared genes and thus pathways associated with severity of response to RSV infection and asthma risk can help us to understand mechanisms of disease and ultimately propose new and novel targets for primary prevention of both diseases.

Hypertriglyceridemia-induced pancreatitis and risk of persistent systemic inflammatory response syndrome

BACKGROUND

The mechanisms responsible for the development of acute pancreatitis (AP) and its complications are not fully understood.

AIM

To assess the role of clinical and host molecular factors for the development and outcome of persistent systemic inflammatory response syndrome (SIRS) in patients with AP.

METHODS

We included 191 patients with AP in the study. The considered variables were demographic characteristics, prognosis and outcome, etiology, laboratory findings and complications. Interleukin (IL) 10 (-1082 G/A, -592 C/A), TNFA-308 (G/A) and ILB-31 (C/T) polymorphisms were determined by pyrosequencing. An amplification refractory mutation system-polymerase chain reaction method was used to genotype the IL8-251 (A/T) polymorphism.

RESULTS

Demographic characteristics were not statistically significant risk factors for the acquisition of persistent SIRS in patients with AP. Patients with hypertriglyceridemia were more likely to develop persistent SIRS (P < 0.05). No association with the TNFA, ILB, IL8-251 (A/T) and IL10 single-nucleotide polymorphisms was detected from the allele, genotype or haplotype frequencies.

CONCLUSIONS

Patients with hypertriglyceridemia-induced AP were more likely to develop persistent SIRS.

Clinical associations of host genetic variations in the genes of cytokines in critically ill patients

Host genetic variations may influence a changing profile of biochemical markers and outcome in patients with trauma/injury. The objective of this study was to assess clinical associations of single nucleotide polymorphisms (SNPs) in the genes of cytokines in critically ill patients. A total of 430 patients were genotyped for SNPs in the genes of pro- (IL1B, IL6, IL8) and anti-inflammatory (IL4, IL10, IL13) cytokines. The main end-points were sepsis, mortality and adult respiratory distress syndrome (ARDS). We evaluated the dynamic levels of bilirubin, blood urea nitrogen, creatine kinase, creatinine and lactate dehydrogenase in five points of measurements (between 1 and 14 days after admission) and correlated them with SNPs. High-producing alleles of proinflammatory cytokines protected patients against sepsis (IL1B -511A and IL8 -251A) and mortality (IL1B -511A). High-producing alleles of anti-inflammatory cytokines IL4 -589T and IL13 431A (144Gln) were less frequent in ARDS patients. The carriers of IL6 -174C/C genotypes were prone to the increased levels of biochemical markers and acute kidney and liver insufficiency. Genotype-dependent differences in the levels of biochemical indicators gradually increased to a maximal value on the 14th day after admission. These findings suggest that genetic variability in pro- and anti-inflammatory cytokines may contribute to different clinical phenotypes in patients at high risk of critical illness.

Interleukin-8 -251A/T gene polymorphism and lung cancer susceptibility: a meta-analysis

Many studies have examined the association between the interleukin-8 -251T/A (rs4073) gene polymorphism and lung cancer risk in various populations, but the results have been inconsistent. In this meta-analysis, PubMed was searched for case-control studies published through 01 December 2013. The data were extracted, and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. We assessed six published studies on the association between the interleukin-8 -251T/A polymorphism and lung cancer risk. The included studies yielded a total of 3265 lung cancer cases and 3607 controls. For the homozygous A/A and A allele carriers (T/A + A/A), the pooled ORs for all studies combining 3265 cases and 3607 controls were 1.03 (95% CI = 0.92-1.14; P = 0.235 for heterogeneity) and 1.07 (95% CI = 0.96-1.19; P = 0.245 for heterogeneity) when compared with the homozygous wild-type genotype (T/T). When the analysis was stratified by ethnicity, significant risks were found among Asians for both the A allele carriers and the homozygous A/A individuals. However, no significant associations were found in non-Asian populations using any of the genetic models. This meta-analysis suggests that the interleukin-8 -251A allele confer an increased risk for the development of lung cancer among Asians.

Association between interleukin 8 -251 A/T and +781 C/T polymorphisms and osteoarthritis risk

PURPOSE

Interleukin 8 (IL-8), as a member of the CXC chemokine family, has a regulatory role in joint inflammation and cartilage degradation, and contribute to the pathophysiology of osteoarthritis. The aim of the current study was to examine the influence of the IL-8 gene polymorphisms at positions -251 (rs4073) and +781 (rs2227306) on the risk of osteoarthritis.

METHODS

This hospital-based case-control study comprised 150 patients with osteoarthritis and 150 age- and gender-matched controls. IL-8 251 A/T and +781 C/T polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Patients with osteoarthritis had a significantly higher frequency of IL-8 -251 TT genotype [odds ratio (OR)=2.16, 95% confidence interval (CI)=1.09, 4.26; P=0.03], IL-8 -251 T allele (OR=1.41, 95% CI=1.02, 1.94; P=0.04), IL-8 +781 TT genotype (OR=2.79, 95% CI=1.10, 7.08; P=0.03) and IL-8 +781 T allele (OR=1.48, 95% CI=1.02, 2.14; P=0.04) than controls. But the findings are less emphatic by the Bonferroni correction. When stratifying by body mass index, type, articular involvement, and Kellgren-Lawrence grade, no significant differences were found in any groups.

CONCLUSIONS

For the first time, the current data suggested that the TT genotype and T allele of the IL-8 gene polymorphisms at positions -251 and +781 might confer a high risk of osteoarthritis. In the future, additional well-designed large studies were required for the validation of our results.

Respiratory syncytial virus--a comprehensive review

Respiratory syncytial virus (RSV) is amongst the most important pathogenic infections of childhood and is associated with significant morbidity and mortality. Although there have been extensive studies of epidemiology, clinical manifestations, diagnostic techniques, animal models and the immunobiology of infection, there is not yet a convincing and safe vaccine available. The major histopathologic characteristics of RSV infection are acute bronchiolitis, mucosal and submucosal edema, and luminal occlusion by cellular debris of sloughed epithelial cells mixed with macrophages, strands of fibrin, and some mucin. There is a single RSV serotype with two major antigenic subgroups, A and B. Strains of both subtypes often co-circulate, but usually one subtype predominates. In temperate climates, RSV infections reflect a distinct seasonality with onset in late fall or early winter. It is believed that most children will experience at least one RSV infection by the age of 2 years. There are several key animal models of RSV. These include a model in mice and, more importantly, a bovine model; the latter reflects distinct similarity to the human disease. Importantly, the prevalence of asthma is significantly higher amongst children who are hospitalized with RSV in infancy or early childhood. However, there have been only limited investigations of candidate genes that have the potential to explain this increase in susceptibility. An atopic predisposition appears to predispose to subsequent development of asthma and it is likely that subsequent development of asthma is secondary to the pathogenic inflammatory response involving cytokines, chemokines and their cognate receptors. Numerous approaches to the development of RSV vaccines are being evaluated, as are the use of newer antiviral agents to mitigate disease. There is also significant attention being placed on the potential impact of co-infection and defining the natural history of RSV. Clearly, more research is required to define the relationships between RSV bronchiolitis, other viral induced inflammatory responses, and asthma.

Ethnic differences in gastric cancer genetic susceptibility: Allele flips of interleukin gene

Polymorphisms in promoter regions of inflammatory cytokines have been widely studied, and potentially functional polymorphisms have been discovered. Conflicting results from meta-analyses of interleukin (IL)-1B and IL-10 polymorphisms show differences in gastric cancer susceptibilities between Caucasian and Asian populations. In particular, we note the suggestion of an allele flip in IL-1B and IL-10 gene polymorphisms. In Asian populations, the IL-1B-1464G/-511C/-31T haplotype indicates risk for gastric cancer, while the opposite haplotype, IL-1B-1464C/-511T/-31C is the risk-related allele in Caucasians. Furthermore, while IL-10-1082G/-819C/-592C is associated with gastric cancer in Asians, IL-10-1082A/-819T/-592T is linked to gastric cancer risk in Caucasians. These seemingly contradictory results may be attributed to distinct carcinogenic mechanisms underlying the different gastric cancer subtypes. The allele flip observed in IL-10 and gastric cancer appears to reflect allelic heterogeneity, similar to that observed in IL-1B. In this review, we focus on the allele flip phenomenon observed between different ethnic groups in an effort to resolve certain controversial results from recent studies on interleukin polymorphism. In addition, we re-emphasize the importance of stratifying gastric cancer subtypes based on anatomical site and Lauren classification to prevent false associations arising through dilution of true ones.

Interleukin 8 promoter polymorphism predicts the initial response to bevacizumab treatment for exudative age-related macular degeneration

PURPOSE

To study the association of single-nucleotide polymorphisms of interleukin 8, vascular endothelial growth factor, erythropoietin, complement factor H, complement component C3, and LOC387715 genes with the response to bevacizumab treatment in exudative age-related macular degeneration.

METHODS

Clinical records, smoking history, optical coherence tomography, and angiographies of 96 bevacizumab-treated exudative age-related macular degeneration patients were analyzed retrospectively. Blood DNA was collected. Based on the disappearance of intra- or subretinal fluid in optical coherence tomography, patients were graded as responders, partial responders, or nonresponders after 3 initial treatment visits and a median time of 3.5 months.

RESULTS

Interleukin 8 promoter polymorphism -251A/T was significantly associated with persisting fluid in optical coherence tomography. The A allele was more frequent in nonresponders than in responders (P = 0.033). In multivariate modeling, the AA genotype of -251A/T (P = 0.043) and occult (P = 0.042) or predominantly classic (P = 0.040) lesions predicted poorer outcome. Visual acuity change was better in responders than in nonresponders (P = 0.006). Baseline lesion size (P = 0.006) and retinal cysts after the treatment (P < 0.001) correlated with less visual acuity gain.

CONCLUSION

The A allele and the homozygous AA genotype of interleukin 8 -251A/T were associated with anatomical nonresponse to bevacizumab treatment.

The relationship between respiratory syncytial virus and asthma

Asthma is a chronic inflammatory disease of the lung that is a leading cause of morbidity and mortality in children worldwide. Most infants who experience wheezing episodes also exhibit evidence of an ongoing respiratory viral infection. Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infection in children and is a common cause of wheezing in infants and young children. In the past several decades, a number of studies have demonstrated a relationship between infants with severe RSV infections and the subsequent development of asthma later during childhood. This review provides an overview of data that suggests a severe RSV infection early in childhood is linked to development of asthma later in life. In addition, the current and potential future use of various animal models to gain additional insight into the relationship between RSV and asthma is discussed.

Association of interleukin-8 gene polymorphisms with the risk of hepatocellular carcinoma

Interleukin-8 (IL8) polymorphisms have been implicated in several cancers, but their roles in the pathogenesis of hepatocellular carcinoma (HCC) are largely unknown. The present study was designed to explore the association between IL8 polymorphism and the risk of HCC in a Chinese population. Four single nucleotide polymorphisms (SNPs) of the IL8 gene -251A/T, +781C/T, -353A/T and +678T/C were analyzed in 205 HCC patients and 208 healthy controls in a Chinese population. Serum levels of IL8 were detected in HCC patients and healthy controls. The association between IL8 polymorphisms and HCC risk was measured using the adjusted odds ratios (OR) and their 95% confidence intervals (CI) from multiple logistic regression analysis. Haplotype analysis and gene-environment interaction analysis was also performed. The serum level of IL8 was significantly higher in HCC patients compared with healthy controls (P < 0.001). After adjusting for confounding factors, no significant associations were found between -251A/T, +781C/T, -353A/T and +678T/C and HCC risk (all P > 0.05). Haplotype analysis showed that A(251)-C(781)-A(353)-C(678) conferred decreased risk of HCC onset (adjusted OR 0.31, 95% CI 0.13-0.77). No significant interaction effects were found between the four SNPs and HBV infection, cirrhosis, gender smoking and alcohol consumption (all P > 0.05). No association between -251A/T, +781C/T, -353A/T and +678T/C of the IL8 gene and the risk of HCC was found in this Chinese population, and the SNPs did not display any interaction with several environmental factors with regard to HCC risk. However, it appears that A(251)-C(781)-A(353)-C(678) is perhaps a protective haplotype for HCC.

Computation vs. cloning: evaluation of two methods for haplotype determination

Nuclear sequence data, often from multiple loci, are increasingly being employed in analyses of population structure and history, yet there has been relatively little evaluation of methods for accurately and efficiently separating the alleles or haplotypes in heterozygous individuals. We compared the performance of a computational method of haplotype reconstruction and standard cloning methods using a highly variable intron (ornithine decarboxylase, intron 6) in three closely related species of dabbling ducks (genus Anas). Cloned sequences from 32 individuals were compared to results obtained from phase 2.1.1 . phase correctly identified haplotypes in 28 of 30 heterozygous individuals when the underlying model assumed no recombination. Haplotypes of the remaining two individuals were also inferred correctly except for unique polymorphisms, the phase of which was appropriately indicated as uncertain (phase probability = 0.5). For a larger set of 232 individuals, results were essentially identical regardless of the recombination model used and haplotypes for all 30 of the tested heterozygotes were correctly inferred, with the exception of uncertain phase for unique polymorphisms in one individual. In contrast, initial sequences of one clone per sample yielded accurate haplotype determination in only 26 of 30 individuals; polymerase chain reaction (PCR)/cloning errors resulting from misincorporation of individual nucleotides could be recognized and avoided by comparison to direct sequences, but errors due to PCR recombination resulted in incorrect haplotype reconstruction in four individuals. The accuracy of haplotypes reconstructed by phase, even when dealing with a relatively small number of samples and numerous variable sites, suggests broad utility of computational approaches for reducing the cost and improving the efficiency of data collection from nuclear sequence loci.

Comparison of cytokine gene polymorphisms among Greek patients with invasive meningococcal disease or viral meningitis

High levels of pro-inflammatory cytokines are implicated in the severity of invasive meningococcal disease (IMD) and viral meningitis (VM). This study compared single-nucleotide polymorphisms (SNPs) in pro- and anti-inflammatory cytokine genes among patients with VM or IMD. Patient DNA samples were prepared by the National Meningitis Reference Laboratory in Athens: n = 98 for IMD and n = 53 for VM. The results for both patient groups were compared with data published for healthy Greek control data. Real-time PCR was used to assess the interleukin (IL) gene SNPs IL6 G−174C, IL1B C−511T, IL1RN T+2018C, IL10 G−1082A and IL8 A−251T and the tumour necrosis factor α (TNF-α) SNP TNFA G−308A. Differences were compared by Fisher’s exact test. The genotype for high IL-6 responses was predominant among IMD (51 %, P = 0.0008) and VM (74.5 %, P<0.0001) patients compared with the controls (31 %). The genotype associated with high TNF-α responses was 5 % among controls and lower for IMD (1.1 %, P = 0.0014) and VM (0 %, P = 0.052). There was no difference for IL-8 SNPs between controls and IMD (P = 0.162), but the difference was significant for VM (P = 0.0025). IL-6 (P = 0.024) and IL-8 (P = 0.00004) SNPs differed between IMD and VM. Reports on associations between IL-8 SNPs and cytokine responses differ. Because of its role in neutrophil attraction, differences in frequencies of the IL-8 SNP for IMD and VM require further investigation.

DNA methylation at promoter regions of interleukin 1B, interleukin 6, and interleukin 8 in non-small cell lung cancer

Epidemiologic and experimental evidences support the concept that inflammation promotes the development and progression of cancers. Interleukins (ILs) regulate the expression of several molecules and signaling pathways involved in inflammation. High expression of some ILs in the tumor microenvironment has been associated with a more virulent tumor phenotype. To examine the role of IL-1β, IL-6, and IL-8 in non-small cell lung cancer, we measured mRNA levels and promoter DNA methylation in a panel of cultured human lung cells (n = 23) and in matched pair lung tumor versus adjacent non-tumorous tissues (n = 24). We found that lung cancer cells or tissues had significantly different DNA methylation and mRNA levels than normal human bronchial epithelial cells or adjacent non-tumorous tissues, respectively. High DNA methylation of ILs promoters in lung cancer cells or tissues was associated with low mRNA levels. We found an inverse correlation between DNA methylation of IL1B, IL6, and IL8 gene promoters and their corresponding mRNA levels, such inverse correlation was more significant for IL1B (i.e., all cancer cell lines used in this study had a hypermethylated IL1B promoter which was associated with silencing of the gene). Our results underline for the first time the role of epigenetic modifications in the regulation of the expression of key cytokines involved in the inflammatory response during lung cancer development.

Changes of the cytokine profile in inflammatory bowel diseases

Cytokines are indispensable signals of the mucosa-associated immune system for maintaining normal gut homeostasis. An imbalance of their profile in favour of inflammation initiation may lead to disease states, such as that is observed in inflammatory bowel diseases (IBD). Although Crohn's disease (CD) is often described as a prototype of T-helper 1-type diseases, and ulcerative colitis (UC) is traditionally viewed as a T-helper 2-mediated condition, the classic paradigm, which categorises cytokines into pro- and anti-inflammatory groups, has recently been changed. The inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological settings. None the less there are many common immunological responses in IBD that are mediated by cytokines. Although they regulate and influence the development, course and recurrence of the inflammatory process, the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the disease. Our aim is to review the current information about pro- and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and CD. The better understanding of their production and functional activity may lead to the development of new therapeutic modalities.

Characterization of the resistance of SJL/J mice to pneumonia virus of mice, a model for infantile bronchiolitis due to a respiratory syncytial virus

Respiratory syncytial virus (RSV), a prominent cause of airway morbidity in children, maintains an excessive hospitalization rate despite decades of research. Host factors are assumed to influence the disease severity. As a first step toward identifying the underlying resistance mechanisms, we recently showed that inbred mouse strains differ dramatically as regards their susceptibility to pneumonia virus of mice (PVM), the murine counterpart of RSV. PVM infection in mice has been shown to faithfully mimic the severe RSV disease in human infants. This study aimed at dissecting the remarkable PVM-resistance shown by the SJL/J strain. To characterize its genetic component, we assessed clinical, physiopathological, and virological resistance/susceptibility traits in large first (F1) and second (F2) generations obtained by crossing the SJL/J (resistant) and 129/Sv (susceptible) strains. Then, to acquire conclusive in vivo evidence in support of the hypothesis that certain radiosensitive hematopoietic cells might play a significant role in PVM-resistance, we monitored the same resistance/susceptibility traits in mock- and γ-irradiated SJL/J mice. Segregation analysis showed that (i) PVM-resistance is polygenic, (ii) the resistance alleles are recessive, and (iii) all resistance-encoding alleles are concentrated in SJL/J. Furthermore, there was no alteration of SJL/J PVM-resistance after immunosuppression by γ-irradiation, which suggests that adaptive immunity is not involved. We conclude that host resistance to pneumoviruses should be amenable to genetic dissection in this mouse model and that radioresistant lung epithelial cells and/or alveolar macrophages may control the clinical severity of pneumovirus-associated lung disease.

Uteroglobulin-related protein 1 and severity of respiratory syncytial virus infection in children admitted to hospital

There are several reports suggesting that genetic factors contribute to the severity of infection with the respiratory syncytial virus (RSV). Infants hospitalized with lower respiratory tract infection (LRTI) due to RSV are at a significantly increased risk for both recurrent wheezing and childhood asthma. Uteroglobin-related protein 1 (UGRP1) is a secretory protein expressed in the airways, and speculated to have anti-inflammatory activity. The presence of the -112G/A polymorphism in the UGRP1 promoter was found to have a significant correlation with asthma phenotype. Also plasma UGRP1 levels were shown to be associated both with this polymorphism and the severity of asthma. The study population consisted of 62 previously healthy infants, ≤12 months of age, who were hospitalized with RSV LRTI, and a control group of 99 healthy adults. Genotyping was performed by restriction fragment length polymorphism. UGRP1 serum levels were determined using ELISA. There were no significant differences in the overall distribution of UGRP1 -112G/A polymorphism genotypes or alleles between the hospitalized infants and healthy adults. A comparison of serum UGRP1 concentration measured at the time of admission and discharge between patients with and without the -112A allele revealed that there was no relation between the presence of the -112A allele and serum UGRP1 in hospitalized infants with RSV infection. Furthermore, there was no relationship between severity of RSV infection and genotype or serum UGRP1 concentration. These results suggest that UGRP1 does not have a major role in the development of severe RSV infection.

Genetic variations of interleukin-8, CXCR1 and CXCR2 genes and risk of acute pyelonephritis in children

Acute pyelonephritis (APN) is the most severe form of urinary tract infection, the etiopathogenesis of which is still not well understood. Previous studies demonstrated that chemotaxis of neutrophils into the tissue and across the infected epithelial layer is a key step in rapid bacterial clearance. Variations within genes encoding the major chemokine interleukin-8 and its receptors CXCR1 and CXCR2 are therefore attractive candidates for participation in genetic predisposition to APN. The aim of our study was to evaluate the association of single nucleotide polymorphisms (SNPs) -251 T/A, +781 C/T, +1633 C/T and +2767 A/T in the IL-8 gene, +2608 G/C in the CXCR1 gene and +1208 C/T in the CXCR2 gene with susceptibility to APN in the Slovak population. PCR-SSP and PCR-RFLP were used to genotype SNPs in 147 children with APN (62 with recurrent and 85 with episodic form) and 215 healthy individuals. Statistical analysis revealed significantly increased frequency of CXCR1 +2608 C allele (P = 0.0238, OR = 2.452, 95% CI = 1.147-5.243) and GC genotype (P = 0.0201, OR = 2.627, 95% CI = 1.188-5.810) and lower frequency of CXCR2 +1208 T allele (P = 0.0408, OR = 0.645, 95% CI = 0.429-0.972) and TT+TC genotypes (P = 0.0497, OR = 0.5273, 95% CI = 0.288-0.964) in patients with recurrent APN compared with healthy controls. Furthermore, the A allele of IL-8 -251 T/A SNP was also significantly overrepresented in patients with recurrent APN when compared with those with only single episode of APN (P = 0.0439, OR = 1.627, 95% CI = 1.019-2.599). Our results indicate that the minor CXCR1 +2608 C allele is associated with significantly increased susceptibility to APN in childhood, while the CXCR2 +1208 T allele confers protection from recurrent APN. Moreover, allele A of the IL-8 -251 T/A may also increase the risk of developing recurrent attacks after the first-time APN.

Functional characterisation of bovine interleukin 8 promoter haplotypes in vitro

Interleukin 8 (IL-8) is a major mediator of the innate immune response and polymorphisms in this gene are associated with susceptibility to inflammatory disease in humans. The aim of this study was to characterise the promoter region of the bovine IL8 gene towards understanding its regulation and the effect of promoter polymorphisms on gene expression levels. Twenty-nine polymorphic sites were identified across a 2.1kb upstream promoter region of the IL8 gene including two insertion/deletion polymorphisms. Sequence analysis and SNP genotyping identified two distinct promoter haplotypes (IL8-h1 and IL8-h2), which were present at significantly different frequencies in two divergently selected cattle breeds - Holstein-Friesian and Norwegian Red (IL8-h1 at 48% and 80% respectively). IL8-h1 was functionally less responsive in unstimulated mammary epithelial cells and in response to stimulation with LPS or bovine TNF. Serial deletion analysis and in silico transcription-factor binding site analysis indicated that allele specific binding of the transcriptional repressor Oct-1 may account for the reduced sensitivity of IL8-h1. Our finding of genetic variation in the bovine IL8 promoter that differentially regulates its expression has significant functional implications for IL8 expression in vitro and which may impact on susceptibility to bovine infectious disease and inflammation.