Association of respiratory syncytial virus bronchiolitis with the interleukin 8 gene region in UK families

The role of cytokines and chemokines in severe respiratory syncytial virus infection and subsequent asthma

Respiratory syncytial virus (RSV) is the primary cause of serious lower respiratory tract illness in infants and young children worldwide. The mechanism is largely unknown. RSV stimulates airway epithelial cells and resident leukocytes to release cytokines. Cytokines and chemokines involved in host response to RSV infection are thought to play a central role in the pathogenesis. In addition, RSV infection early in life has been associated with the development of asthma in later childhood. It is likely that the persistence of cytokines and chemokines in fully recovered patients with RSV in the long term can provide a substratum for the development of subsequent asthma. This review describes the genetic factors in cytokines and chemokines associated with severity of RSV disease, cytokines and chemokines synthesis in RSV infection, and the role of these innate immune components in RSV-associated asthma.

Genetic susceptibility to the delayed sequelae of neonatal respiratory syncytial virus infection is MHC dependent

Respiratory syncytial virus (RSV) is a major cause of respiratory morbidity, resulting in hospitalization for bronchiolitis in some infected infants that is associated with wheeze in later life. Genetic factors are known to affect the severity of the sequelae after RSV infection, but the complexity of the temporal and genetic effects makes it difficult to analyze this response in studies in man. Therefore, we developed a murine genetic model to analyze the sequelae occurring after RSV infection in early life. Haplotype-based genetic analysis of interstrain differences in severity identified the MHC as an important genetic determinant. This was confirmed by analysis of responses in congenic mice with different MHC haplotypes. We also found that susceptible strains had high CD8 levels during secondary infection. Analysis of first filial generation, second filial generation, and back-cross progeny produced by intercrossing resistant (H-2(k), C3H/HeN) and sensitive (H-2(b), BALB/c) strains indicated that susceptibility to sequelae after RSV infection was dominantly inherited but also segregated in a non-MHC-dependent manner. Thus, MHC haplotype and its effect on CD8 cell response is an important determinant of the outcome of neonatal RSV infection.

Biological pathways and genetic variables involved in pain

PURPOSE

This paper summarizes current knowledge of pain-related and analgesic-related pathways as well as genetic variations involved in pain perception and management.

METHODS

The pain group of the GENEQOL Consortium was given the task of summarizing the current status of research on genetic variations in pain and analgesic efficacy. This review is neither exhaustive nor comprehensive; we focus primarily on single-nucleotide polymorphisms.

RESULTS

Two categories of potential genetic pain-perception pathways were identified: neurotransmission modulators and mechanisms that affect inflammation. Four categories were identified for analgesic efficacy: genes related to receptor interaction, modulation of opioid effects, metabolism, and transport. Various genetic variations involved in these pathways are proposed as candidate genetic markers for pain perception and for individual sensitivity to analgesics.

CONCLUSIONS

Candidate gene association studies have been used to provide evidence for the genetic modulation of pain perception and response to analgesics. However, the nature and range of genetic modulation of pain is not well addressed due to the limited number of patients and the limited number of genes and genetic variants investigated in studies to date. Moreover, personalized analgesic treatments will require a more complete understanding of the effects of genetic variants and gene-gene interactions in response to analgesics.

Genetic variants in inflammation-related genes are associated with radiation-induced toxicity following treatment for non-small cell lung cancer

Treatment of non-small cell lung cancer (NSCLC) with radiotherapy or chemoradiotherapy is often accompanied by the development of esophagitis and pneumonitis. Identifying patients who might be at increased risk for normal tissue toxicity would help in determination of the optimal radiation dose to avoid these events. We profiled 59 single nucleotide polymorphisms (SNPs) from 37 inflammation-related genes in 173 NSCLC patients with stage IIIA/IIIB (dry) disease who were treated with definitive radiation or chemoradiation. For esophagitis risk, nine SNPs were associated with a 1.5- to 4-fold increase in risk, including three PTGS2 (COX2) variants: rs20417 (HR:1.93, 95% CI:1.10-3.39), rs5275 (HR:1.58, 95% CI:1.09-2.27), and rs689470 (HR:3.38, 95% CI:1.09-10.49). Significantly increased risk of pneumonitis was observed for patients with genetic variation in the proinflammatory genes IL1A, IL8, TNF, TNFRSF1B, and MIF. In contrast, NOS3:rs1799983 displayed a protective effect with a 45% reduction in pneumonitis risk (HR:0.55, 95% CI:0.31-0.96). Pneumonitis risk was also modulated by polymorphisms in anti-inflammatory genes, including genetic variation in IL13. rs20541 and rs180925 each resulted in increased risk (HR:2.95, 95% CI:1.14-7.63 and HR:3.23, 95% CI:1.03-10.18, respectively). The cumulative effect of these SNPs on risk was dose-dependent, as evidenced by a significantly increased risk of either toxicity with an increasing number of risk genotypes (P<0.001). These results suggest that genetic variations among inflammation pathway genes may modulate the development of radiation-induced toxicity and, ultimately, help in identifying patients who are at an increased likelihood for such events.

Paget's disease of bone is not associated with common polymorphisms in interleukin-6, interleukin-8 and tumor necrosis factor alpha genes

BACKGROUND

Cytokines, specially interleukin (IL)-6, play an important role in the differentiation and activation of osteoclasts and might be involved in osteoblast stimulation in Paget's disease of bone (PDB).

OBJECTIVES

The aim of this study was to investigate the association of polymorphisms in IL-6, IL-8 and tumor necrosis factors-alpha (TNFA) genes among Spanish patients with PDB.

METHODS

We studied four single nucleotide polymorphisms (-174 G>C IL-6, -251 T>A IL-8, -238 G>A TNFA and -308 G>A TNFA) in 172 PDB patients and 150 healthy controls. Distribution of alleles and pro-inflammatory genotypes were studied for association with the presence of the disease and with clinical and laboratory data, as well as the response to bisphosphonate treatment in PDB patients.

RESULTS

We found no statistically significant association between genotype and allele distribution of any of the cytokines polymorphism studied and PDB. No association between the clinical and therapeutic characteristics of PDB and the investigated polymorphism were found.

CONCLUSIONS

This study does not support the hypothesis that the analyzed IL6, IL8 and TNFA polymorphism are associated with PDB.

Haplotype of IL-8 -251T and 781C is associated with the susceptibility to respiratory syncytial virus

OBJECTIVE

To study the association of haplotypes of IL-8 -251T/A and 781 C/T single nucleotide polymorphisms (SNPs) with the susceptibility of respiratory syncytial virus (RSV).

METHODS

This study included 101 hospitalized patients under 2 years who suffered from RSV pneumonia and 108 hospitalized patients under 2 years who suffered only from pneumonia without RSV infection. Genotypes of two SNP loci in all enrolled persons were defined by allele-specific polymerase chain reaction. The allele's frequencies of SNPs were analyzed with case-control study, linkage of two loci and haplotypes composed by the two loci were also studied.

RESULTS

(i) The frequency of IL-8 -251T in cases was dramatically high (OR = 2.08, p = 0.0002). (ii) Haplotype of TC was significantly high in cases (p = 0.01).

CONCLUSION

These findings support that haplotype of TC composed by IL-8 -251T and 781C is associated with the susceptibility of RSV.

Interleukin-1beta and -10 polymorphisms influence erosive reflux esophagitis and gastritis in Taiwanese patients

BACKGROUND AND AIMS

Helicobacter pylori (H. pylori) infection induces cytokine production and is associated with gastrointestinal diseases. This study examined the relationship of gene polymorphisms, including interleukin (IL)-1beta, -10, -8, and tumor necrosis factor-alpha (TNF-alpha), H. pylori infection, and susceptibility to gastrointestinal disorders in Taiwanese patients.

METHODS

IL-1beta-511/-31/+3953, -10-1082/-819/-592, -8-251, and TNF-alpha-308 polymorphisms were assessed in 628 gastrointestinal disease patients, and 176 healthy controls were analyzed using the polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

IL-1beta-511 T/T and -31 C/C genotypes, and IL-1beta-511 T and -31 C alleles were associated with an increased risk of reflux esophagitis (P = 0.034, odds ratio [OR] = 1.384, 95% confidence interval [CI]: 1.023-1.871; P = 0.031, OR = 1.388, 95% CI: 1.028-1.873; P = 0.044, OR = 1.342, 95% CI: 1.008-1.786; and P = 0.040, OR = 1.349, 95% CI: 1.014-1.796, respectively). No relationship was found between H. pylori infection and the risk of reflux esophagitis. IL-10-819 C/T and -10-592 A/C genotypes and IL-10-1082/-819/-592 ATA/ACC and ATA/GCC haplotypes were associated with an increased risk of gastritis (P = 0.021, OR = 1.721, 95% CI: 1.084-2.733; P = 0.016, OR = 1.766, 95% CI: 1.112-2.805; P = 0.039, OR = 1.662, 95% CI: 1.024-2.697; and P = 0.035, OR = 1.600, 95% CI: 1.024-2.499, respectively).

CONCLUSION

Among Taiwanese patients, IL-1beta and -10 polymorphisms were associated with an increased risk of erosive reflux esophagitis and gastritis, respectively.

Genetic associations with asthma and virus-induced wheezing: a systematic review

Various wheezing phenotypes can be identified based on differences in natural histories, risk factors and responses to treatment. In epidemiologic studies, atopic asthma or virus-induced wheezing can be discriminated by the presence or the absence of sensitization to allergens. Children with asthma have been shown to present lower levels of lung function. Patients with viral respiratory infections evolve from normal lung function to enhanced airway reactivity. The objective of this study was to identify genes and polymorphisms associated with different wheezing phenotypes. Using data obtained from the Genetic Association Database, we systematically reviewed studies on genes and polymorphisms that have been associated with virus-induced wheezing or atopic asthma. The research was carried out in February of 2009. Genes associated with the studied outcomes in more than three studies were included in the analysis. We found that different genes and loci have been associated with virus-induced wheezing or atopic asthma. Virus-induced wheezing has frequently been associated with IL-8 polymorphisms, whereas atopic asthma and atopy have frequently been associated with Th2 cytokine gene (CD14 and IL-13) polymorphisms on chromosome 5. This review provides evidence that different wheezing disorders in childhood can be differently affected by genetic variations, considering their role on airway inflammation and atopy. Future studies of genetic associations should consider the different wheezing phenotypes in infancy. In addition, stratified analyses for atopy can be useful for elucidating the mechanisms of the disease.

Combined effects of IL-8 and CXCR2 gene polymorphisms on breast cancer susceptibility and aggressiveness

Background

Interleukin-8 (IL-8/CXCL-8) is a prototype of the ELR⁺CXC chemokines that play an important role in the promotion and progression of many human cancers including breast cancer. We have recently showed the implication of polymorphism (-251) T/A of IL-8 gene in the susceptibility and prognosis of breast carcinoma. IL-8 acts through its CXCR1 and CXCR2 receptors. CXCR2, expressed on the endothelial cells, is the receptor involved in mediating the angiogenic effects of ELR⁺CXC chemokines and in particular IL-8.

In the current study, we investigated the susceptibility and prognostic implications of the genetic variation in CXCR2 in breast carcinoma. We also confirmed the implication of IL-8 (-251) T/A polymorphism in a larger cohort. Finally, we combined the IL-8 and CXCR2 variant alleles and analyzed their effects in breast cancer risk and prognosis.

Methods

We used the allele-specific polymerase chain reaction to characterize the variation of IL-8 and CXCR2 for 409 unrelated Tunisian patients with breast carcinoma and 301 healthy control subjects. To estimate the relative risks, Odds ratios and 95% confidence intervals were calculated using unconditional logistic regression after adjusting for the known risk factors for breast cancer. Associations of the genetic marker with the rates of breast carcinoma-specific overall survival and disease-free survival were assessed using univariate and multivariate analyses.

Results

A highly significant association was found between the homozygous CXCR2 (+ 1208) TT genotype (adjusted OR = 2.89; P = 0.008) and breast carcinoma. A significantly increased risk of breast carcinoma was associated with IL-8 (-251) A allele (adjusted OR = 1.86; P = 0.001). The presence of two higher risk genotypes (the TA and TT in IL-8, and the TT in CXCR2) significantly increased the risk of developing breast carcinoma (adjusted OR = 4.15; P = 0.0004).

The CXCR2 (+ 1208) T allele manifested a significant association with an aggressive phenotype of breast carcinoma as defined by a large tumor size, a high histological grade, and auxiliary's lymph node metastasis. A significant association between the IL-8 (-251) A allele and the aggressive form of breast carcinoma was also found.

Moreover, the presence of the IL-8 (-251) A and/or the CXCR2 (+ 1208) T allele showed a significant association with a decreased overall survival and disease-free survival in breast carcinoma patients.

Conclusion

Our results indicated that the polymorphisms in IL-8 and CXCR2 genes are associated with increased breast cancer risk, as well as disease progress, supporting our hypothesis for IL-8 and ELR⁺CXC chemokine receptor (CXCR2) involvement in breast cancer pathogenesis.

Inflammatory genetic markers of prostate cancer risk

Prostate cancer is the most common cancer in Western society males, with incidence rates predicted to rise with global aging. Etiology of prostate cancer is however poorly understood, while current diagnostic tools can be invasive (digital rectal exam or biopsy) and/or lack specificity for the disease (prostate-specific antigen (PSA) testing). Substantial histological, epidemiological and molecular genetic evidence indicates that inflammation is important in prostate cancer pathogenesis. In this review, we summarize the current status of inflammatory genetic markers influencing susceptibility to prostate cancer. The focus will be on inflammatory cytokines regulating T-helper cell and chemokine homeostasis, together with the Toll-like receptors as key players in the host innate immune system. Although association studies indicating a genetic basis for prostate cancer are presently limited mainly due to lack of replication, larger and more ethnically and clinically defined study populations may help elucidate the true contribution of inflammatory gene variants to prostate cancer risk.

Association of interleukin-8 gene polymorphisms and haplotypes with oral lichen planus in a Chinese population

Interleukin-8 (IL-8), a CXC chemokine with multiple biological functions, plays an important role in the pathogenesis of oral lichen planus (OLP). The aim of this study was to investigate the association of single nucleotide polymorphisms (SNPs) of IL-8 gene with OLP in a Chinese population. Four SNPs of the IL-8 gene at positions -845 T/C (rs2227532), -738 T/A, -251 A/T (rs4073) and +781 C/T (rs2227306) were analyzed in 109 patients with OLP and 101 normal controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The data revealed that the -251 AA genotype and -251 A allele frequency was significantly lower in the erosive OLP (eOLP) group than in the control group (P = 0.012 and P = 0.031, respectively). Haplotype analysis revealed that the -251 A/+781 C haplotype frequency was lower in the eOLP group than in the control group (P = 0.029) while the -251 T/+781 C haplotype frequency was higher in the eOLP patients than in the healthy controls (P = 0.028). The study suggests that the IL-8 polymorphisms may be associated with the severity of OLP in this Chinese cohort.

Association of haplotypes in the IL8 gene with susceptibility to chronic periodontitis in a Brazilian population

BACKGROUND

Interleukin 8 (IL-8) is a chemokine related to the initiation and amplification of acute and chronic inflammatory processes. Polymorphisms in the IL8 gene have been associated with inflammatory diseases. We investigated whether the -845(T/C) and -738(T/A) single nucleotide polymorphisms (SNPs) in the IL8 gene, as well as the haplotypes they form together with the previously investigated -353(A/T), are associated with susceptibility to chronic periodontitis.

METHODS

DNA was extracted from buccal epithelial cells of 400 Brazilian individuals (control n=182, periodontitis n=218). SNPs were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Disease associations were analyzed by the chi(2) test, Exact Fisher test and Clump program. Haplotypes were reconstructed using the expectation-maximization algorithm and differences in haplotype distribution between the groups were analyzed to estimate genetic susceptibility for chronic periodontitis development.

RESULTS

When analyzed individually, no SNPs showed different distributions between the control and chronic periodontitis groups. Although, nonsmokers carrying the TTA/CAT (OR=2.35, 95% CI=1.03-5.36) and TAT/CTA (OR=6.05, 95% CI=1.32-27.7) haplotypes were genetically susceptible to chronic periodontitis. The TTT/TAA haplotype was associated with protection against the development of periodontitis (for nonsmokers OR=0.22, 95% CI=0.10-0.46).

CONCLUSION

Although none of the investigated SNPs in the IL8 gene was individually associated with periodontitis, some haplotypes showed significant association with susceptibility to, or protection against, chronic periodontitis in a Brazilian population.

Polymorphisms in inflammatory genes, plasma antioxidants, and prostate cancer risk

BACKGROUND

Presence of xenotropic murine leukemia virus-related virus and chronic inflammation in prostate tumor suggests that inflammation plays a role in prostate cancer etiology. This study investigated whether variants in inflammatory genes act alone or interact with plasma antioxidants to influence prostate cancer risk in a population-based case-control study in Central Arkansas.

METHODS

Cases (n = 193) were men, aged 40-80, diagnosed with prostate cancer in three major hospitals in 1998-2003, and controls (n = 197) were matched to cases by age, race, and county of residence.

RESULTS

After adjustment for confounders, polymorphisms in COX-2 (rs689466) and IL-8 (rs4073) were not significantly associated with prostate cancer risk. However, apparent interactions were observed between these genetic variants and plasma antioxidants on the risk of this malignancy. The protective effect of the mutant allele of the COX-2 polymorphism was more pronounced among subjects with high plasma levels of beta-cryptoxanthin, lycopene, beta-carotene, or selenium (>or=median) [e.g., OR (95% CI): 0.37 (0.15, 0.86) (AG/GG vs. AA) for beta-cryptoxanthin]. Conversely, the promoting effect of the variant allele of the IL-8 polymorphism was more remarkable in subjects with low plasma levels of Lutein/zeaxanthin, beta-cryptoxanthin, and beta-carotene (<median) [e.g., OR (95% CI): 2.44 (1.08, 5.75) (AT/TT vs. AA) for beta-carotene].

CONCLUSIONS

We found that sequence variants in inflammatory genes interact with plasma antioxidants to modulate prostate cancer risk.

IL-8 -251A/T polymorphism is associated with decreased cancer risk among population-based studies: evidence from a meta-analysis

Growing evidence suggests that interleukin-8 (IL-8) play pivotal roles in the pathogenesis of cancer through the modulation of tumour immune response or enhanced angiogenesis. A single nucleotide polymorphism, -251A/T, has been identified in the promoter region of the IL-8 gene and has been shown to influence its production. Results from previous studies on the association of -251A/T polymorphism with different cancer types remained contradictory. To assess the effect of -251A/T of IL-8 on cancer susceptibility, we conducted a meta-analysis, up to May 2009, of 14,876 cases with different cancer types and 18,465 controls from 45 published case-control studies. Summary odds ratios and corresponding 95% confidence intervals (CIs) for IL-8 polymorphism and cancer were estimated using fixed- and random-effects models when appropriate. The AA/AT genotypes were associated with a significantly increased risk of nasopharyngeal carcinoma when compared with TT genotype (OR=1.48; 95% CI, 1.16-1.89). Moreover, significantly elevated risks were observed in 'other cancers', and also in African population when population is concerned. Interestingly, when stratified separately by population-based studies and hospital-based studies, significantly elevated risk was found among hospital-based studies (OR=1.21, 95% CI, 1.07-1.37), whereas significantly decreased risk was found among population-based studies (OR=0.90, 95% CI, 0.83-0.97). This meta-analysis shows that IL-8 -251A/T polymorphism may play a complex role in cancer development.

Influence of interleukin polymorphisms on development of gastric cancer and peptic ulcer

Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous studies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2.02, 1.31-3.10). In peptic ulcer development, IL-2-330 G and IL-4-590 T allele carriers had a significantly decreased risk (0.37, 0.27-0.50 and 0.58, 0.34-0.99, respectively). Moreover, IL-2, IL-4, IL-6 and IL-8 gene genotypes prevalence differs among populations. The inflammatory cytokine gene polymorphisms (e.g. IL-4-590 and IL-6-572 for gastric cancer, and IL-4-590, IL-6-572 and IL-8-251 for peptic ulcer) have a more potent influence on development of gastroduodenal diseases in Western than East Asian populations. These cytokine gene polymorphisms, as well as those of IL-1B, IL-1RN and TNF-A, may be used to identify groups at higher risk of gastric cancer and peptic ulcer, and those suitable for their prevention by H. pylori eradication therapy in Western populations.

Cytokine gene polymorphisms and sudden infant death syndrome

AIM

Several studies indicate that the mucosal immune system is stimulated in cases of sudden infant death syndrome (SIDS), and our hypothesis is that this immune reaction is because of an unfavourable combination of functional polymorphisms in the cytokine genes.

METHODS

Thus, in this study, single nucleotide polymorphisms (SNPs) in the genes encoding IL-6, IL-8, IL-12, IL-13, IL-16, IL-18 and IFNgamma were investigated in 148 SIDS cases, 56 borderline SIDS cases, 41 cases of infectious death and 131 controls.

RESULTS

Regarding genotype distribution, no differences between the investigated groups were found. However, in the SIDS group, the genotypes IL-8 -251AA/AT and IL-8 -781CT/TT were significantly more frequent in the SIDS cases found dead in a prone sleeping position, compared with SIDS cases found dead in other sleeping positions. In addition, there was an association between fever prior to death and the genotype IL-13 +4464GG in the cases of infectious death.

CONCLUSION

This study indicates that specific interleukin genotypes are a part of a genetic make up that make infants sleeping prone at risk for SIDS.

IL-8 -251 T > A polymorphism is associated with bladder cancer susceptibility and outcome after BCG immunotherapy in a northern Indian cohort

BACKGROUND AND AIMS

Chemokines and transcription factor NF-kappaB play a pivotal role in development of carcinoma of the bladder (CaB). The present study was conducted to analyze the association of chemokines IL-8 -251 T>A and +678 C>T and NF-kappaB -94 (ATTG) insertion/deletion polymorphisms with the risk of CaB and outcome after bacillus Calmette-Guerin (BCG) immunotherapy in a cohort of northern India.

METHODS

Histologically confirmed 205 CaB cases and 270 controls were included. Of these, 71 patients were treated with BCG immunotherapy. Genotyping was done using allele-specific PCR methodology.

RESULTS

The variant genotype (AA) of IL-8 -251 polymorphism was associated with more than 2-fold risk of CaB (OR 2.12; p = 0.003; 95% CI 1.28-3.52). None of the other genotypes showed association with CaB risk. Subsequently, the diplotype -251A/+678T demonstrated a 1.8-fold increased risk for CaB (OR 1.84, 95% CI 1.37-2.47). Furthermore, -251 AA genotypes reduced the risk of recurrence after BCG immunotherapy (AA; HR 0.12; 95% CI 0.04-0.41). Subsequently, improved recurrence-free survival (mean recurrence-free survival for GG, GA and AA genotypes was 24, 39 and 53 months respectively). Similarly, NF-kappaB ATTG Ins/Ins genotype was at reduced risk of recurrence after BCG treatment compared to Del/Del genotype, which exhibited a 2.5-fold increased risk of recurrence in patients treated with BCG immunotherapy (HR, 2.53; 95% CI 1.00-6.36). Subsequently, mean recurrence-free survival (Ins/Ins, 41; Ins/Del, 44 and Del/Del, 10 months; log rank, 0.030).

CONCLUSIONS

Our results suggested that the IL-8 -251 T>A polymorphism may be a relevant host susceptibility factor for bladder carcinoma development and may influence outcome after BCG immunotherapy. Similarly, NF-kappaB ATTG polymorphism may also modify risk-free survival of BCG-treated patients.

Association of common polymorphisms in IL10, and in other genes related to inflammatory response and obesity with colorectal cancer

OBJECTIVE AND METHODS

The association of 17 candidate single nucleotide polymorphisms (SNPs) in IL10 and other immune response genes (CRP, TLR4, IL6, IL1B, IL8, TNF, RNASEL) and genes related to obesity (PPARG, TCF7L2, ADIPOQ, LEP) with colorectal cancer was investigated. Haplotype tagging SNPs were chosen for IL10, CRP, and TLR4. Incident colorectal cancer cases (n = 208) and matched controls (n = 381) were identified between baseline in 1989 and 2003 among participants in the CLUE II cohort. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using conditional logistic regression.

RESULTS

Compared with the AA genotype at the candidate IL10-1082 locus (rs1800896), carrying one (OR, 0.79; 95% CI, 0.53-1.18) or two (OR, 0.58; 95% CI, 0.35-0.95) G alleles, a known higher producer of the anti-inflammatory cytokine IL-10, was associated with lower risk of colorectal cancer (p trend = 0.03). Statistically significant associations with colorectal cancer were observed for three tagSNPs in IL10 (rs1800890, rs3024496, rs3024498) and one common haplotype, but these associations were due to high linkage disequilibrium with IL10-1082. Two CRP haplotypes (global p = 0.04) and TLR4 tagSNPs (rs7873784, rs11536891), but not TLR4 haplotypes, were associated with colorectal cancer.

CONCLUSIONS

Our study suggests that polymorphisms in IL10, and also possibly in CRP and other genes related to immune response or obesity may be associated with colorectal cancer.

Respiratory viral infections in infants: causes, clinical symptoms, virology, and immunology

In global terms, respiratory viral infection is a major cause of morbidity and mortality. Infancy, in particular, is a time of increased disease susceptibility and severity. Early-life viral infection causes acute illness and can be associated with the development of wheezing and asthma in later life. The most commonly detected viruses are respiratory syncytial virus (RSV), rhinovirus (RV), and influenza virus. In this review we explore the complete picture from epidemiology and virology to clinical impact and immunology. Three striking aspects emerge. The first is the degree of similarity: although the infecting viruses are all different, the clinical outcome, viral evasion strategies, immune response, and long-term sequelae share many common features. The second is the interplay between the infant immune system and viral infection: the immaturity of the infant immune system alters the outcome of viral infection, but at the same time, viral infection shapes the development of the infant immune system and its future responses. Finally, both the virus and the immune response contribute to damage to the lungs and subsequent disease, and therefore, any prevention or treatment needs to address both of these factors.

Innate immunity in ocular Chlamydia trachomatis infection: contribution of IL8 and CSF2 gene variants to risk of trachomatous scarring in Gambians

BACKGROUND

Trachoma, a chronic keratoconjunctivitis caused by Chlamydia trachomatis, is the world's commonest infectious cause of blindness. Blindness is due to progressive scarring of the conjunctiva (trachomatous scarring) leading to in-turning of eyelashes (trichiasis) and corneal opacification. We evaluated the contribution of genetic variation across the chemokine and cytokine clusters in chromosomes 4q and 5q31 respectively to risk of scarring trachoma and trichiasis in a large case-control association study in a Gambian population.

METHODS

Linkage disequilibrium (LD) mapping was used to investigate risk effects across the 4q and 5q31 cytokine clusters in relation to the risk of scarring sequelae of ocular Ct infection. Disease association and epistatic effects were assessed in a population based study of 651 case-control pairs by conditional logistic regression (CLR) analyses.

RESULTS

LD mapping suggested that genetic effects on risk within these regions mapped to the pro-inflammatory innate immune genes interleukin 8 (IL8) and granulocyte-macrophage colony stimulatory factor (CSF2) loci. The IL8-251 rare allele (IL8-251 TT) was associated with protection from scarring trachoma (OR = 0.29 p = 0.027). The intronic CSF2_27348 A allele in chromosome 5q31 was associated with dose dependent protection from trichiasis, with each copy of the allele reducing risk by 37% (p = 0.005). There was evidence of epistasis, with effects at IL8 and CSF2 loci interacting with those previously reported at the MMP9 locus, a gene acting downstream to IL8 and CSF2 in the inflammatory cascade.

CONCLUSION

innate immune response SNP-haplotypes are linked to ocular Ct sequelae. This work illustrates the first example of epistatic effects of two genes on trachoma.

Genomewide association analysis of respiratory syncytial virus infection in mice

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infection in infants, with about half being infected in their first year of life. Yet only 2 to 3% of infants are hospitalized for RSV infection, suggesting that individual susceptibility contributes to disease severity. Previously, we determined that AKR/J (susceptible) mice developed high lung RSV titers and showed delayed weight recovery, whereas C57BL/6J (resistant) mice demonstrated low lung RSV titers and rapid weight recovery. In addition, we have reported that gene-targeted mice lacking the cystic fibrosis transmembrane conductance regulator (Cftr; ATP-binding cassette subfamily C, member 7) are susceptible to RSV infection. For this report, recombinant backcross and F2 progeny derived from C57BL/6J and AKR/J mice were infected with RSV, their lung titers were measured, and quantitative trait locus (QTL) analysis was performed. A major QTL, designated Rsvs1, was identified on proximal mouse chromosome 6 in both recombinant populations. Microarray analysis comparing lung transcripts of the parental strains during infection identified several candidate genes that mapped to the Rsvs1 interval, including Cftr. These findings add to our understanding of individual RSV susceptibility and strongly support a modifier role for CFTR in RSV infection, a significant cause of respiratory morbidity in infants with cystic fibrosis.

Association of interleukin-8 with cachexia from patients with low-third gastric cancer

Background. Interleukin (IL)-8 has been implicated in the development of cancer cachexia. The polymorphism of IL-8 gene, which may affect the production level of IL-8, may be associated with cancer cachexia. Methods. The serum IL-8 level in our study was examined by radioimmunoassay. We also analyzed single nucleotide polymorphisms (SNPs) −251 A/T and +781 C/T of IL-8 gene, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. The serum levels of IL-8 were significantly elevated in patients with low-third gastric cancer compared with controls, and were further up-regulated in patients with cachexia than those without (Z = −3.134, P = .002). A significantly increased frequency of +781 T allele was noted in patients with cachexia (OR = 2.247, 95% CI: 1.351–3.737, P = .002). The +781 TT genotype was observed to be associated with a significantly increased risk of cachexia (OR = 3.167, 95% CI: 1.265–7.929, P = .011), and with odds ratio of 3.033 (95% CI: 1.065–8.639, P = .038) for cachexia after adjusting for potential confounding factors. Meanwhile, haplotype analysis indicated a borderline positive association between T²⁵¹T⁷⁸¹ haplotype and cachexia as compared with the T²⁵¹C⁷⁸¹ haplotype (OR = 4.92, 95% CI: 1.00–24.28;, P = .053). Conclusions. IL-8 appears to be associated with cachexia from patients with low-third gastric cancer.

Polymorphisms in inflammation genes, tobacco smoke and furred pets and wheeze in children

Persistent wheeze in childhood is associated with airway inflammation. The present study investigated relationships between polymorphisms in inflammatory genes, exposure to tobacco smoke and furred pets and risk of recurrent wheeze in children. Within a birth cohort of 101,042 children we identified 1111 eighteen month old cases with recurrent wheeze and 735 wheeze-free controls among 11942 children recruited in the Copenhagen area. Polymorphisms in IL-4R, IL-8, IL-13, SPINK5, and CD14 were genotyped. Interviews at gestational wks 12 and 30, and at age 6 and 18 months included questions on number of episodes with wheeze (18 months), exposure to tobacco smoke and pet-keeping. Recurrent wheeze was defined as at least four episodes of wheeze before the child was 18 months old. There was a statistically significant association between the IL-13 Arg144Gln polymorphism and risk of recurrent wheeze (p = 0.01). Furthermore, there was a statistically significant interaction between this polymorphism and exposure to tobacco smoke during pregnancy, though this was probably a chance finding. There were no other statistically significant effects of the polymorphisms or interactions with exposure to tobacco smoke in relation to the risk of recurrent wheeze. Polymorphisms in IL-8 affected the association between pet-keeping and risk of wheeze. Polymorphisms in inflammation genes might affect the association between environmental exposures and risk of recurrent wheeze in early childhood.

Effect of variation in RANTES promoter on serum RANTES levels and risk of recurrent wheezing after RSV bronchiolitis in children from Han, Southern China

To investigate the association among RANTES (regulated on activation normal T cell expressed and secreted) gene promoter polymorphism, serum RANTES levels, and recurrent wheezing after RSV (respiratory syncytial virus) bronchiolitis in children (1-12 months of age) from Han, Southern china. Three hundred twenty children with RSV bronchiolitis and 272 controls were enrolled in the 3-year follow-up study. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RELP), enzyme-linked immunosorbent assay (ELISA) kit and luciferase analysis were the mainly used methods, which were used to genotype the RANTES (-403 G/A), assess the serum RANTES levels and the RANTES promoter activity. As the results showed, the RANTES (-403 G/A) in the promoter region was associated with recurrent wheezing after RSV bronchiolitis (p < 0.05) and serum RANTES levels (RANTES genotype G/G: 26.03 +/- 7.46 ng/ml G/A: 28.22 +/- 6.44 ng/ml A/A: 30.12 +/- 5.88 ng/ml). Functional analyses of RANTES promoter activity indicated that the RANTES (-403 G to A) mutation increases the transcriptional activity of the RANTES promoter. In conclusion, the RANTES (-403 G/A) polymorphism increases RANTES transcriptional activity resulted in a high serum RANTES levels, thus increased the risk of recurrent wheezing after RSV bronchiolitis.

Genetic variations in angiogenesis pathway genes associated with clinical outcome in localized gastric adenocarcinoma

BACKGROUND

Angiogenesis has been attributed to be a well-recognized aspect of human cancer biology. As such, proteinase-activated receptor (PAR)-1, endostatin (ES) and interleukin-8 (IL-8) mediate the regulation of early-onset angiogenesis and in turn impact the process of tumor-growth and disease progression.

PATIENTS AND METHODS

Formalin-fixed paraffin-embedded tissues were obtained from 137 patients with localized gastric cancer at University of Southern California and Memorial Sloan-Kettering Cancer Center medical facilities. DNA was extracted and genotyping was carried out using PCR-restriction fragment length polymorphism-based protocols.

RESULTS

In false discovery rate-adjusted univariate analysis, PAR-1 -506 ins/del (P < 0.001), ES +4349 G>A (P = 0.004), and IL-8 -251 T>A (P < 0.0001) were associated with time to tumor recurrence (TTR). Further, PAR-1 -506 ins/del and IL-8 -251 were associated with overall survival (OS). After adjusting for covariates, IL-8 remained significantly associated with TTR (adjusted P = 0.003) and OS (adjusted P = 0.049), whereas ES was significantly associated with TTR (adjusted P = 0.026).

CONCLUSIONS

Polymorphisms in PAR-1, ES, and IL-8 may serve as independent molecular prognostic markers in patients with localized gastric adenocarcinoma. The assessment of the patients' individual risk on the basis of interindividual genotypes may therefore help to identify patient subgroups at high risk for poor clinical outcome.

Cytokine responses in cord blood predict the severity of later respiratory syncytial virus infection

BACKGROUND

It has been claimed that an early respiratory syncytial virus (RSV) infection can induce asthma and recurrent wheezing.

OBJECTIVE

We addressed the question of whether infants contracting an early RSV infection differ from healthy children in their cytokine production at birth.

METHODS

In a prospective cohort study cord blood samples were collected from 1084 newborns during autumn 2001. Of 47 of these newborns with subsequent virologically confirmed RSV infection before 6 months of age, 24 had enough cells for stimulation in cord blood samples (14 of those were hospitalized). Twenty-eight children had other respiratory virus infections (16 with enough cells), and samples from 48 healthy children of the 1084 total served as control specimens. Stimulated cytokine production of mononuclear cells was measured. The responses in the groups were evaluated by means of factor analysis.

RESULTS

The infants hospitalized for RSV infection had higher LPS-stimulated combined IL-6 and IL-8 responses than the infants treated as outpatients (P = .005) or the healthy control subjects (P = .02). The hospitalized patients with RSV showed lower IL-1beta, IL-2, IL-4, IL-5, and IL-10 responses than those treated as outpatients (P = .02). High IL-6 and IL-8 responsiveness predicted a severe RSV infection (odds ratio, 2.20; 95% CI, 1.17-4.14; P = .01). The unstimulated cytokine responses at birth did not differ between the patients and healthy control subjects.

CONCLUSION

The results suggest that natural differences in innate immunity predispose children to severe RSV infection rather than the infection modifying immune responses in childhood.

The effects of genetic polymorphisms of IL-6, IL-8, and IL-10 on Helicobacter pylori-induced gastroduodenal diseases in Korea

BACKGROUND

The genes that encode proinflammatory and anti-inflammatory cytokines are good candidate markers of host susceptibility to gastroduodenal disease. The present study was performed to evaluate whether or not the genetic polymorphisms of IL-6, IL-8, and IL-10 are associated with gastroduodenal disease in the Korean population.

METHODS

This study enrolled 1187 patients, including controls, those with gastric cancer (GC), benign gastric ulcer (BGU), and duodenal ulcer patients. Six polymorphisms were genotyped, 3 of IL-10 (at -592, -819, and -1082), 1 of IL-8 (at -251), and 2 of IL-6 (at -174 and -572), by polymerase chain reaction-restriction fragment length polymorphism analysis.

RESULTS

The frequency of IL-10-1082 G carriers was higher in cases of a diffuse type GC [odds ratio (OR) 1.8, 95% confidence interval (CI): 1.0-3.1, P=0.041] or BGU (OR 1.6, 95% CI: 1.0-2.5, P=0.040), than in the control group regardless of Helicobacter pylori infection. The IL-8-251 A/A genotype was more common in H. pylori-positive patients with GC (OR 2.0, 95% CI: 1.2-3.6, P=0.013) or BGU (OR 2.7, 95% CI: 1.5-4.8, P=0.001) than in H. pylori-positive controls. In addition, the frequencies of IL-6-572 G/G (OR 0.3, 95% CI: 0.1-0.9, P=0.027) and of G carriers (OR 0.5, 95% CI: 0.4-0.8, P=0.003) were lower in H. pylori-positive duodenal ulcer patients than in H. pylori-positive controls. IL-10-592 C/C (OR 0.4, 95% CI: 0.2-0.9, P=0.028) was an independent factor associated with a decreased risk of the intestinal type of GC by multivariate analysis. Furthermore, a synergistic effect was observed between IL-10-592 A/A and IL-8-251 A/A with respect to the development of GC or BGU.

CONCLUSIONS

These results suggest that the genetic polymorphisms of these 3 inflammation-related cytokines, IL-10, IL-8, and IL-6, are associated with the development of H. pylori-associated gastroduodenal disease.

Recognizing the importance of respiratory syncytial virus in chronic obstructive pulmonary disease

Acute exacerbations of chronic obstructive pulmonary disease (COPD) are responsible for a large proportion of the health care dollar expenditure, morbidity, and mortality related to COPD. Respiratory infections are the most common cause of acute exacerbations, but recent evidence indicates that the importance of respiratory syncytial virus (RSV) infection in COPD is under-appreciated. Improved detection of RSV using techniques based on the polymerase chain reaction accounts for much of the increased recognition of the importance of this virus in COPD patients. Furthermore, COPD patients may be more susceptible to RSV infection, possibly due to RSV-or immune response-induced pulmonary effects that are altered by age, environmental exposures, genetics, COPD itself, or a combination of these. However, although RSV infection occurs throughout life, viral and host factors that place COPD patients at increased risk are unclear. The complexities of RSV effects in COPD present opportunities for research with the goal of developing approaches to selectively modify damaging viral effects (e.g., altered airway function), while retaining beneficial immunity (e.g., clearance of virus) in COPD patients. This review explores the role RSV plays in acute exacerbations of COPD, the potential for RSV disease in chronic stable COPD, and newer concepts in RSV diagnosis, epidemiology, and host defense.

Common variants of inflammatory cytokine genes are associated with risk of nephropathy in type 2 diabetes among Asian Indians

Background

Inflammatory cytokine genes have been proposed as good candidate genes for conferring susceptibility to diabetic nephropathy. In the present study, we examined the combined effect of multiple alleles of pro inflammatory cytokine genes for determining the risk of nephropathy in type 2 diabetic patients.

Methodology/Principal Findings

Eight single nucleotide polymorphisms (SNPs) of pro-inflammatory cytokine genes (CCL2, TGFB1, IL8, CCR5, and MMP9) were genotyped in two independently ascertained type 2 diabetic cohorts with (DN) and without nephropathy (DM); consisting of patients from North India (n = 495) and South India (n = 188). Genotyping was carried out using PCR, allele specific oligonucleotide-PCR (ASO-PCR), PCR-RFLP and TaqMan allelic discrimination assays and the gene–gene interaction among genetic variants were determined by multi dimensional reduction (MDR) software. Serum high sensitive CRP (hs-CRP) levels were measured by ELISA. The hs-CRP levels were significantly higher in DN as compared to the DM group (p<0.05). The CCL2, IL8, CCR5 and MMP9 polymorphisms were found to be associated with the risk of diabetic nephropathy. Frequency of CCL2 II, IL8 -251AA, CCR5 59029AA and MMP9 279Gln/Gln genotypes were significantly higher in DN than in DM group (p<0.05) and associated with an increased risk of nephropathy in both North and South Indian cohorts. CCR5 DD and IL8 -251AA genotypes were more prevalent in North Indian DN group only. The co-occurrence of risk associated genotypes (II, -2518GG (CCL2), DD (CCR5) and 279Gln/Gln (MMP9) conferred a tenfold increased risk of nephropathy among type 2 diabetics (p<0.0002).

Conclusion

The present study highlights that common variants of inflammatory cytokine genes exert a modest effect on risk of DN and a combination of risk alleles confer a substantial increased risk of nephropathy in type 2 diabetes among Asian Indians.

Genetic polymorphisms of interleukin 8 and risk of ulcerative colitis in the Chinese population

BACKGROUND

Interleukin-8 (IL-8), a CXC chemokine that recruits and activates inflammatory cells, plays a critical role in the pathogenesis of ulcerative colitis (UC). There are no studies on the association of single nucleotide polymorphisms (SNPs) of the IL-8 gene with the risk of UC.

METHODS

All 162 unrelated UC patients and 203 control subjects were analyzed for 5 IL-8 SNPs ((-845 (T/C), -738 (T/A), -353 (A/T), -251 (T/A) and +678 (T/C)) using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay and PCR-sequence-specific primers (SSP) method. Serum IL-8 concentrations were measured in all subjects.

RESULTS

Individual SNPs were not associated with risk for UC. However, the frequency of -353A/-251A/+678T haplotype was significantly higher in UC patients than in healthy controls (OR=1.454, p=0.036). By subgroup analyses, this haplotype tended to be more common in severe UC patients than in those with mild-to-moderate disease (OR=2.281, p=0.027). Furthermore, patients with AAT diplotype showed significantly increased serum IL-8 concentrations than those with other diplotypes (p<0.001).

CONCLUSION

These results suggest that IL-8 is a novel susceptibility gene to UC in Chinese UC patients, and furthermore, that IL-8 polymorphisms may be related to severe clinical subtype of UC.

Genetic association study for RSV bronchiolitis in infancy at the 5q31 cytokine cluster

BACKGROUND

The pathophysiological basis of severe respiratory syncytial virus (RSV) bronchiolitis in infancy is poorly understood and has hindered vaccine development. Studies implicate the cell-mediated immune response in the pathogenesis of the disease. A recent twin study estimated a heritable contribution of 22% to RSV bronchiolitis. Genetic epidemiology provides a new approach to identifying important immune determinants of disease severity.

METHODS

A comprehensive high-density gene-region association study for severe RSV bronchiolitis in infancy at 5q31 across 11 genes including the Th2-cytokine cluster was performed. A haplotype tagging approach was used to analyse genetic variation at 113 single nucleotide polymorphisms (SNPs) in 780 independent cases and 1045 controls. The study had sufficient power to detect small effects, perform extensive haplotype analysis and analyse both a principal phenotype and a refined age-limited phenotype enriched for first-exposure RSV infection.

RESULTS

SNP associations were found at IL4 and a highly significant risk haplotype was identified across IL13 CNS-1 and IL4 (odds ratio 1.69, p<0.0001), present in both case-control and family-based analyses. All associations were strongest for a phenotype limited to <6 months of age, implicating this locus in primary RSV disease. The same risk haplotype has previously been shown to be associated with increased IL13 expression.

CONCLUSIONS

A haplotype at IL13-1L4, which is associated with increased IL13 production, confers an increased risk of severe primary RSV bronchiolitis in early infancy. This study, together with previous studies implicating the same locus in atopic sensitisation, suggests that primary RSV bronchiolitis and atopy share a genetic contribution at the IL13-IL4 locus.

Analysis of inflammation- and atherosclerosis-related gene polymorphisms in branch retinal vein occlusion

PURPOSE

Branch retinal vein occlusion (BRVO) is a common vision-threatening disease. Compression of the underlying retinal vein due to increased rigidity of the crossing artery has been implicated in the pathogenesis of BRVO. Among others, arterial hypertension and hypercholesterolemia, both of which contribute to atherogenesis, have been identified as risk factors. Atherosclerosis itself is a chronic low-grade inflammatory disease with a distinct pro-inflammatory cytokine pattern. In addition to their role in atherogenesis, some cytokines have been shown to exert procoagulatory effects, and may thus contribute to the development of BRVO by a second mechanism. Gene polymorphisms affecting the expression of inflammation-related cytokines are therefore candidates as potential risk factors for BRVO. The purpose of the present study was to investigate hypothesized associations between cytokine gene polymorphisms and the presence of BRVO.

METHODS

The study comprised 398 patients with BRVO and 355 control subjects. Using 5'exonuclease assays (TaqMan), genotypes of the following functional single nucleotide polymorphisms were determined: interleukin 1 beta (IL1B) -511C>T, interleukin 1 receptor antagonist (IL1RN) 1018T>C, interleukin 4 (IL4) -584C>T, interleukin 6 (IL6) -174G>C, interleukin 8 (IL8) -251A>T, interleukin 10 (IL10) -592C>A, interleukin 18 (IL18) 183A>G, tumor necrosis factor (TNF) -308G>A, monocyte chemoattractant protein 1 (CCL2) -2518A>G, and RANTES (CCL5) -403G>A.

RESULTS

Neither genotype distributions nor allele frequencies of any of the investigated polymorphisms differed significantly between BRVO patients and controls (p>0.05). Arterial hypertension was found to be significantly more prevalent in BRVO patients than in controls (p<0.001). In a logistic regression analysis presence of arterial hypertension was associated with an odds ratio of 3.33 (95% confidence interval: 2.42-4.57) for BRVO.

CONCLUSIONS

As none of the investigated gene variants was significantly more prevalent in BRVO patients than among control subjects, our data suggest that these polymorphisms themselves are unlikely major risk factors for BRVO.

Serum concentrations of cytokines and lung cancer survival in African Americans and Caucasians

Accumulating evidence suggests a role for inflammation in the development and progression of cancer. Our group recently identified a cytokine gene signature in lung tissue associated with lung cancer prognosis. Therefore, we hypothesized that concentrations of circulating cytokines in serum may be associated with lung cancer survival. Ten serum cytokines, namely, interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, interferon (IFN)-gamma, and tumor necrosis factor-alpha, were assessed in 353 non-small cell lung cancer cases from a case-control study of lung cancer in the greater Baltimore, Maryland area. Cytokines were measured using an ultrasensitive electrochemiluminescence immunoassay. IL-6 serum concentrations (>or=4.0 pg/mL) were associated with significantly poorer survival in both African Americans [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.26-5.80] and Caucasians (HR, 1.71; 95% CI, 1.22-2.40). IL-10 (HR, 2.62; 95% CI, 1.33-5.15) and IL-12 (HR, 1.98; 95% CI, 1.14-3.44) were associated with lung cancer survival only in African Americans. Some evidence for an association of tumor necrosis factor-alpha levels with survival in Caucasians was observed, although these results were not significant. These hypothesis-generating findings indicate that selected serum cytokine concentrations are associated with lung cancer survival, and indicate that further research is warranted to better understand the mechanistic underpinnings of these associations.

Genetic diversity of the host and severe respiratory syncytial virus-induced lower respiratory tract infection

Respiratory syncytial virus (RSV)-induced lower respiratory tract disease is a common problem in children and adults in Western societies. The clinical range of RSV infection from asymptomatic to respiratory distress syndrome is believed to be the outcome of viral and host immunity interactions. Genes associated with immune response are of particular interest regarding genetic predisposition to severe RSV infection. Several investigators have sought to identify genetic markers for high-risk patients, and more than 20 independent studies in the medical literature assess the impact of genetic variations-mostly single nucleotide polymorphisms-on the clinical presentation of RSV-induced disease. Several candidate gene loci have been tested in association studies based on the concept that a particular allele is a significant risk factor for a phenotype of interest. Despite the wealth of information available, we are still far from evolving a practical and cost-effective screening tool; certain flaws in association studies first need to be overcome. The development of haplotype-based analysis for candidate loci across the genome, along with advances in biostatistics and bioinformatics, would facilitate the assessment of the relative contribution of genetic markers to disease susceptibility in RSV infection.

Polymorphisms and clinical outcome in recurrent ovarian cancer treated with cyclophosphamide and bevacizumab

PURPOSE

This study was designed to evaluate the associations between angiogenesis gene polymorphisms and clinical outcome in ovarian cancer patients treated with low-dose cyclophosphamide and bevacizumab.

EXPERIMENTAL DESIGN

Seventy recurrent/metastatic epithelial ovarian cancer patients were enrolled in a phase II clinical trial. Genomic DNA was available from 53 blood samples. Polymorphisms were analyzed using the PCR-RFLP protocol. A 5' end 33P gammaATP-labeled PCR protocol was used to analyze dinucleotide repeats.

RESULTS

Patients genotyped A/A or A/T for the IL-8 T-251A gene polymorphism had a statistically significant lower response rate (19%; 0%) than those homozygous T/T (50%; P = 0.006, Fisher's exact test). Patients carrying a minimum one C allele (C/C; C/T) of the CXCR2 C+785T polymorphism showed a median progression-free survival (PFS) of 7.4 months compared with the PFS of 3.7 months for those homozygous T/T (P = 0.026, log-rank test). Patients with the VEGF C+936T polymorphism C/T genotype had a longer median PFS of 11.8 months, compared with those with the C/C and T/T genotype, which had median PFS of 5.5 months and 3.2 months, respectively (P = 0.061, log-rank test). Patients carrying both AM 3'end alleles < 14 CA repeats had the shortest median PFS of 3.4 months; patients with at least one allele > 14 repeats or both alleles > 14 repeats showed a median PFS of 6.4 months and 7.2 months, respectively (P = 0.008, log-rank test).

CONCLUSION

Our data suggest that the IL-8 A-251T polymorphism may be a molecular predictor of response to bevacizumab-based chemotherapy. The CXCR2 C+785T, VEGF C+936T single nucleotide polymorphisms and the AM 3' dinucleotide repeat polymorphisms may be molecular markers for PFS in ovarian cancer patients.

Multiple organ dysfunction syndrome in children with sepsis: role of genetic factors

This review summarizes current knowledge on the impact of genetic markers on susceptibility, severity, and outcome of acute inflammatory disorders in children, with a special focus on systemic infections. A 14-year-old child with Neisseria meningitides bacteremia, complicated by septic shock and multiple organ dysfunction, is discussed as an exemplary case, and linked to the application of genetic epidemiology and the study of common disorders in children. The current pertinent literature is comprehensively reviewed and limitations and future directions are discussed.

Interleukin-10 is associated with resistance to febrile seizures: genetic association and experimental animal studies

PURPOSE

Febrile seizures (FS) are the most common form of childhood convulsions. Many reports have shown that a proinflammatory cytokine, interleukin-1 (IL-1) beta, may have a facilitatory effect on the development of FS. We have previously shown that the IL1B -511C/T single nucleotide polymorphism (SNP) is associated with simple FS of sporadic occurrence. The balance between pro- and antiinflammatory cytokines influences the regulation of infections and could, therefore, play a role in the pathogenesis of FS. Here, to determine whether pro- and antiinflammatory cytokine genes are responsible for the susceptibility to FS, we have performed an association study on functional SNPs of cytokine genes in FS patients and controls.

METHODS

The promoter SNPs of four inflammatory cytokine genes (IL6 -572C/G, IL8 -251A/T, IL10 -592A/C and TNFA -1037C/T) were examined in 249 patients with FS (186 simple and 63 complex FS) and 225 controls. Because the IL10 -592 SNP showed a positive association with FS, two additional SNPs (IL10 -1082A/G and -819T/C) were subjected to haplotype analysis. Furthermore, we examined the in vivo role of IL-10 in hyperthermia-induced seizures using immature animal models.

RESULTS

The frequencies of the IL10 -592C allele and -1082A/-819C/-592C haplotype were significantly decreased in FS as compared with in controls (p = 0.014 and 0.013, respectively). The seizure threshold temperature in the IL-10-administered rats was significantly higher than that in the saline-treated control ones (p = 0.027).

CONCLUSIONS

The present study suggests that IL-10 is genetically associated with FS and, contrary to IL-1beta, confers resistance to FS.

Innate immune response and bronchiolitis and preschool recurrent wheeze

Bronchiolitis and preschool recurrent wheeze (PSRW) are common paediatric problems causing significant morbidity and mortality in the first years of life. Respiratory syncytial virus (RSV) and rhinoviruses are the commonest pathogens associated with these illnesses. Why some infants are severely affected, requiring admission to hospital, whilst others experience a simple cold is not fully understood: research has suggested that the innate immune response to these viruses is important. The innate immune system has many components and activation or deficiency in one or many areas may explain the different clinical presentations and disease severities that can occur in these infants. This review will summarize the recent evidence highlighting how RSV and rhinoviruses may modulate the innate immune response in both bronchiolitis and PSRW, and discuss how these illnesses affect the long-term development of the infant lung and the possible susceptibility to persistent airway disease.

Cytokine and cytokine receptor gene polymorphisms and their functionality

Cytokines, signaling proteins produced by a variety of cell types, are essential for the development and functioning of both innate and adaptive immune response. Cytokine gene expression is tightly regulated, and aberrant expression from environmental and genetic polymorphism has been implicated in a range of diseases, susceptibility to infections, and responses to treatment. This review concentrates on the functionality of cytokine and cytokine receptor gene polymorphisms; it is through these variants that genuine disease-associations are based. Several mechanisms for single nucleotide polymorphism (SNP) functionality are present within cytokine genes including: amino acid changes (IL-6R, IL-13, IL-1alpha), exon skipping (IL-7Ralpha), proximal promoter variants (IL-1beta, IL-Ra, IL-2, IL-6, IL-10, IL-12, IL-13, IL-16, TNF, IFN-gamma, TGF-beta), distal promoter variants (IL-6, IL-18) and intronic enhancer variants (IL-8).

Attenuated P2X7 pore function as a risk factor for virus-induced loss of asthma control

RATIONALE

Upper respiratory tract infection is a guideline accepted risk domain for the loss of asthma control. The ionotrophic nucleotide receptor P2X(7) regulates compartmentalized acute inflammation and the immune response to airway pathogens.

OBJECTIVES

We hypothesized that variability in P2X(7) function contributes to neutrophilic airway inflammation during a cold and thereby is linked to acute asthma.

METHODS

Research volunteers with asthma were enrolled at the onset of a naturally occurring cold and monitored through convalescence, assessing symptoms, lung function, and airway inflammation. P2X(7) pore activity in whole blood samples was measured using a genomically validated flow cytometric assay.

MEASUREMENTS AND MAIN RESULTS

Thirty-five participants with mild to moderate allergic asthma were enrolled and 31 completed all visits. P2X(7) pore function correlated with the change in nasal lavage neutrophil counts during the cold (R(s) = 0.514, P = 0.004) and was inversely related to the change in asthma symptoms (R(s) = -0.486, P = 0.009). The change in peak expiratory flow recordings, precold use of inhaled corticosteroids, and P2X(7) pore function were multivariate predictors of asthma symptoms (P = 0.001, < 0.001 and = 0.003 respectively). Attenuated P2X(7) activity was associated with the risk of losing asthma control (crude odds ratio, 11.0; 95% confidence interval, 1.1-106.4) even after adjustment for inhaled corticosteroids and rhinovirus (odds ratio, 15.0).

CONCLUSIONS

A whole blood P2X(7) pore assay robustly identifies participants with loss-of-function genotypes. Using this assay as an epidemiologic tool, attenuated P2X(7) pore activity may be a novel biomarker of virus-induced loss of asthma control.

Molecular epidemiology, cancer-related symptoms, and cytokines pathway

The Human Genome Project and HapMap have led to a better appreciation of the importance of common genetic variation in determining cancer risk, created potential for predicting response to therapy, and made possible the development of targeted prevention and therapeutic interventions. Advances in molecular epidemiology can be used to explore the role of genetic variation in modulating the risk for severe and persistent symptoms, such as pain, depression, and fatigue, in patients with cancer. The same genes that are implicated in cancer risk might also be involved in the modulation of therapeutic outcomes. For example, polymorphisms in several cytokine genes are potential markers for genetic susceptibility both for cancer risk and for cancer-related symptoms. These genetic polymorphisms are stable markers and easily and reliably assayed to explore the extent to which genetic variation might prove useful in identifying patients with cancer at high-risk of symptom development. Likewise, they could identify subgroups who might benefit most from symptom intervention, and contribute to developing personalized and more effective therapies for persistent symptoms.