Plasma cytokine levels and cytokine gene polymorphisms in Mexican patients during the influenza pandemic A(H1N1)pdm09

Association of Interleukin-6 (rs1800795) and Interleukin-10 (rs1800896) Genetic Polymorphisms with the Outcome of COVID-19 Infection: A Single Center Study

The corona virus disease-2019 (COVID-19) pandemic has affected most of the world with varying degrees of morbidity and mortality. The presence of genetic polymorphisms may be associated with the severity and outcome of COVID-19 infection. This work aimed to evaluate the genetic polymorphisms of interleukin (IL-6) and IL-10 genes with the outcome of COVID-19 infection. This cross-sectional study was conducted on 354 patients who were classified into moderate and severe cases (including alive and deceased cases). All individuals were genotyped for one SNP for IL-6 (rs1800795) and one SNP for IL10 (rs1800896) using allelic discrimination real-time PCR technique. In this study, 198 cases were moderate, and 156 cases were severe. The risk of allele carriage of the minor allele of IL-6 rs1800795 (C) was significantly higher among the severe group when compared with that of the moderate group (p < 0.0001), while there was a mild significant difference of same allele carriage among alive cases when compared to that of deceased one (p < 0.04). Furthermore, the risk of the C allele of IL-10 rs1800896 was significantly increased in severe cases when compared with the moderate group (p < 0.0001), while there was no significant difference of the risk of the C allele in deceased cases when compared with that of alive ones (p > 0.05). In conclusion, the C allele (rs1800795) of IL-6 and the C allele (rs1800896) of IL-10 were highly significant in severe cases than in moderate cases. The C allele carriage of IL-6 showed only a significant difference between alive and deceased patients and not with the C allele of IL-10.

Different populations of A(H1N1)pdm09 viruses in a patient with hemolytic-uremic syndrome

Respiratory viral infections may have different impacts ranging from infection without symptoms to severe disease or even death though the reasons are not well characterized. A patient (age group 5-15 years) displaying symptoms of hemolytic uremic syndrome died one day after hospitalization. qPCR, next generation sequencing, virus isolation, antigenic characterization, resistance analysis was performed and virus replication kinetics in well-differentiated airway cells were determined. Autopsy revealed hemorrhagic pneumonia as major pathological manifestation. Lung samples harbored a large population of A(H1N1)pdm09 viruses with the polymorphism H456H/Y in PB1 polymerase. The H456H/Y viruses replicated much faster to high viral titers than upper respiratory tract viruses in vitro. H456H/Y-infected air-liquid interface cultures of differentiated airway epithelial cells did reflect a more pronounced loss of ciliated cells. A different pattern of virus quasispecies was found in the upper airway samples where substitution S263S/F (HA1) was observed. The data support the notion that viral quasispecies had evolved locally in the lung to support high replicative fitness. This change may have initiated further pathogenic processes leading to rapid dissemination of inflammatory mediators followed by development of hemorrhagic lung lesions and fatal outcome.

Genetic polymorphisms of IL6 gene -174G > C and -597G > A are associated with the risk of COVID-19 severity

Coronavirus disease-2019 (COVID-19) is pro-inflammatory disorder characterized by acute respiratory distress syndrome. Interleukin-6, a cytokine secreted by macrophages, which mediates an inflammatory response, is frequently increased and associated with the severity in COVID-19 patients. The differential expression of IL6 cytokine in COVID-19 patients may be associated with the presence of single nucleotide polymorphisms (SNPs) in regulatory region of cytokine genes. The aim of this study is to investigate the role of two promoter polymorphisms of the IL6 gene (-597G > A and -174G > C) with the severity of COVID-19. The study included 242 patients, out of which 97 patients with severe symptoms and 145 patients with mild symptoms of COVID-19. Genotyping of two selected SNPs, rs1800795 (-174G > C) and rs1800797 (-597G > A) of promoter region of IL6 gene, was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In our study, individuals with GC genotypes of IL6 (-174G > C) polymorphism showed significantly higher risk of severity [adjusted odds (OR) 3.86, p <.001] but we did not observe any association of COVID-19 severity with rs1800797 (-597G > A) polymorphism. The COVID-19 severity was significantly higher in individuals having 'C' allele of IL6 (-174G > C) polymorphism (p = .014). Linkage disequilibrium between rs1800795 (-174G > C) and rs1800797 (-597G > A) showed that individuals having AC* haplotype significantly association with COVID-19 severity (p = .034). Our results suggest that 'C' allele of rs1800795 (-174G > C) polymorphism of IL6 may be the risk allele for severity of COVID-19 in North Indian population.

Implication of single nucleotide polymorphisms in Interleukin-10 gene (rs1800896 and rs1800872) with severity of COVID-19

Background

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic which has emerged as a new challenge for the medical sciences. Severity of COVID-19 is mostly determined with overexpressed proinflammatory cytokines eventually leading to endothelial dysfunction causing vital organ injury, especially in the lungs. It has been postulated that various genetic mutations might be associated with an increased risk of disease severity in COVID-19. This study was thus carried out to determine the association of rs1800896 and rs1800872 genetic polymorphism in IL-10 gene in determining COVID-19 severity.

Methods

The study included 160 RT-PCR confirmed COVID-19 patients with mild (n = 85) and severe (n = 75) conditions. All subjects were genotyped for Interleukin-10 (rs1800896 and rs1800872) gene polymorphisms using PCR-RFLP technique followed by statistical analysis.

Results

This study found a significant gender and age-based discrepancy in COVID-19 severity with 1.85-and 3.81-fold increased risk of COVID-19 in males of mild and severe groups as compared to females (p = 0.046 and p < 0.001) and 4.35-fold high risk in subjects ≥ 50 (p < 0.001). Genotyping analysis showed that IL-10 (rs1800872) gene polymorphism was strongly associated with COVID-19 severity (p = 0.01) whereas, IL-10 rs1800896 polymorphism was not found to confer the risk of COVID-19 severity in our population.

Conclusion

In this regard, the present study provided an evidence that IL-10 (rs1800872) gene polymorphism is strongly associated with COVID-19 severity and CC genotype confer a protective role in preventing severe disease progression. More detailed studies with a larger sample size on the genetic variations are required to establish the role of studied IL-10 gene polymorphisms with COVID-19 severity.

TNFA and IL10 Polymorphisms and IL-6 and IL-10 Levels Influence Disease Severity in Influenza A(H1N1)pdm09 Virus Infected Patients

Cytokines are key modulators of immune response, and dysregulated production of proinflammatory and anti-inflammatory cytokines contributes to the pathogenesis of influenza A(H1N1)pdm09 virus infection. Cytokine production is impacted by single nucleotide polymorphisms (SNPs) in the genes coding for them. In the present study, SNPs in the IL6, TNFA, IFNG, IL17A, IL10, and TGFB were investigated for their association with disease severity and fatality in influenza A(H1N1)pdm09-affected patients with mild disease (n = 293) and severe disease (n = 86). Among those with severe disease, 41 patients had fatal outcomes. In a subset of the patients, levels of IL-2, IL-4, IL-6, IL-10, TNF, IFN-γ, and IL-17 were assayed in the plasma for their association with severe disease. The frequency of TNFA rs1800629 G/A allele was significantly higher in severe cases and survived severe cases group compared to that of those with mild infection (OR with 95% for mild vs. severe cases 2.95 (1.52–5.73); mild vs. survived severe cases 4.02 (1.84–8.82)). IL10 rs1800896-rs1800872 G-C haplotype was significantly lower (OR with 95% 0.34 (0.12–0.95)), while IL10 rs1800896-rs1800872 G-A haplotype was significantly higher (OR with 95% 12.11 (2.23–76.96)) in fatal cases group compared to that of the mild group. IL-6 and IL-10 levels were significantly higher in fatal cases compared to that of survived severe cases. IL-6 levels had greater discriminatory power than IL-10 to predict progression to fatal outcome in influenza A(H1N1)pdm09 virus-infected patients. To conclude, the present study reports the association of TNFA and IL10 SNPs with severe disease in Influenza A(H1N1)pdm09 virus-infected subjects. Furthermore, IL-6 levels can be a potential biomarker for predicting fatal outcomes in Influenza A(H1N1)pdm09 virus infected subjects.

Association of polymorphisms in tumor necrosis factors with SARS-CoV-2 infection and mortality rate: A case-control study and in silico analyses

The present coronavirus disease 2019 (COVID-19) is spreading rapidly and existing data has suggested a number of susceptibility factors for developing a severe course of the disease.  The current case-control experiment is aimed to study the associations of genetic polymorphisms in tumor necrosis factors (TNFs) with COVID-19 and its mortality rate. A total of 550 participants (275 subjects and 275 controls) were enrolled. The tetra-amplification refractory mutation system polymerase chain reaction technique was recruited to detect -308G>A TNFα and +252A>G TNFβ polymorphisms among the Iranian subjects. We demonstrated that carriers of the G allele of TNFβ-252A/G, rs909253 A>G were more frequent in COVID-19 subjects compared to the healthy group and this allele statistically increased the disease risk (odds ratio [OR] = 1.55, 95% confidence interval [CI] = 1.23-1.96, p < 0.0001). At the same time, the A allele of TNFα-311A/G, rs1800629 G>A moderately decreased the risk of COVID-19 (OR = 0.68, 95% CI = 0.53-0.86, p < 0.002). Also, we analyzed the various genotypes regarding the para-clinical and disorder severity; we found that in the AA genotype of TNFβ-252A/G (rs909253 A>G), the computed tomography scan pattern was different in comparison to cases carrying the AG genotype with p₁  < 0.001. In addition, in the severe cases of COVID-19, leukocyte and neutrophil count and duration of intensive care unit hospitalization in the deceased patients were significantly increased (p < 0.001). Moreover, the TNFα-311A/G (rs1800629 G>A) variant is likely to change the pattern of splicing factor sites. Our findings provided deep insights into the relationship between TNFα/TNFβ polymorphisms and severe acute respiratory syndrome coronavirus 2. Replicated studies may give scientific evidence for exploring molecular mechanisms of COVID-19 in other ethnicities.

Specific Cytokine Profiles Predict the Severity of Influenza A Pneumonia: A Prospectively Multicenter Pilot Study

Purpose

Studying the cytokine profiles in influenza A pneumonia could be helpful to better understand the pathogenesis of the disease and predict its prognosis. Patients and Methods. Patients with influenza A pneumonia (including 2009H1N1, H1N1, H3N1, and H7N1) hospitalized in six hospitals from January 2017 to October 2018 were enrolled (ClinicalTrials.gov ID, NCT03093220). Sputum samples were collected within 24 hours after admission and subsequently analyzed for cytokine profiles using a Luminex assay.

Results

A total of 35 patients with influenza A pneumonia were included in the study. The levels of IL-6, IFN-γ, and IL-2 were increased in patients with severe influenza A pneumonia (n =10) (P = 0.002, 0.009, and 0.008, respectively), while those of IL-5, IL-25, IL-17A, and IL-22 were decreased compared to patients with nonsevere pneumonia (P = 0.0001, 0.009, 0.0001, and 0.006, respectively). The levels of IL-2 and IL-6 in the nonsurvivors (n = 5) were significantly higher than those in the survivors (P = 0.043 and 0.0001, respectively), while the levels of IL-5, IL-17A, and IL-22 were significantly lower (P = 0.001, 0.012, and 0.043, respectively). The IL-4/IL-17A ratio has the potential to be a good predictor (AUC = 0.94, P < 0.05, sensitivity = 88.89%, specificity = 92.31%) and an independent risk factor (OR, 95% CI: 3.772, 1.188-11.975; P < 0.05) for intermittent positive pressure ventilation (n = 9).

Conclusion

Significant dysregulation of cytokine profiles can be observed in patients with severe influenza A pneumonia.

Lack of Effects of the Genetic Polymorphisms of Interleukin-10 in Clinical Outcomes of COVID-19

Interleukin-10 (IL-10) gene polymorphisms have been associated with severity and outcomes in patients with respiratory and nonrespiratory viral infections. The aim of this study was to assess whether rs1800871 and rs1800872 polymorphisms of IL-10 gene are associated with the clinical outcomes of COVID-19 in a Mexican population. Study subjects were 193 COVID-19 patients. The genotyping was carried out with real-time PCR and serum IL-10 levels were measured with enzyme-linked immunosorbent assay. Logistic regression analysis was used for analysis association with clinical outcomes. There was no evidence of an association between alleles, genotypes, or haplotypes frequencies between patient groups according to severity and outcomes. The rs1800871 and rs1800872 polymorphisms might not be genetic risk factors for severity and mortality for COVID-19 in Mexican mestizos patients from northwest Mexico.

Interindividual immunogenic variants: Susceptibility to coronavirus, respiratory syncytial virus and influenza virus

The coronavirus disease (Covid‐19) pandemic is the most serious event of the year 2020, causing considerable global morbidity and mortality. The goal of this review is to provide a comprehensive summary of reported associations between inter‐individual immunogenic variants and disease susceptibility or symptoms caused by the coronavirus strains severe acute respiratory syndrome‐associated coronavirus, severe acute respiratory syndrome‐associated coronavirus‐2, and two of the main respiratory viruses, respiratory syncytial virus and influenza virus. The results suggest that the genetic background of the host could affect the levels of proinflammatory and anti‐inflammatory cytokines and might modulate the progression of Covid‐19 in affected patients. Notably, genetic variations in innate immune components such as toll‐like receptors and mannose‐binding lectin 2 play critical roles in the ability of the immune system to recognize coronavirus and initiate an early immune response to clear the virus and prevent the development of severe symptoms. This review provides promising clues related to the potential benefits of using immunotherapy and immune modulation for respiratory infectious disease treatment in a personalized manner.

Role of the Host Genetic Susceptibility to 2009 Pandemic Influenza A H1N1

Influenza A virus (IAV) is the most common infectious agent in humans, and infects approximately 10-20% of the world's population, resulting in 3-5 million hospitalizations per year. A scientific literature search was performed using the PubMed database and the Medical Subject Headings (MeSH) "Influenza A H1N1" and "Genetic susceptibility". Due to the amount of information and evidence about genetic susceptibility generated from the studies carried out in the last influenza A H1N1 pandemic, studies published between January 2009 to May 2020 were considered; 119 papers were found. Several pathways are involved in the host defense against IAV infection (innate immune response, pro-inflammatory cytokines, chemokines, complement activation, and HLA molecules participating in viral antigen presentation). On the other hand, single nucleotide polymorphisms (SNPs) are a type of variation involving the change of a single base pair that can mean that encoded proteins do not carry out their functions properly, allowing higher viral replication and abnormal host response to infection, such as a cytokine storm. Some of the most studied SNPs associated with IAV infection genetic susceptibility are located in the FCGR2A, C1QBP, CD55, and RPAIN genes, affecting host immune responses through abnormal complement activation. Also, SNPs in IFITM3 (which participates in endosomes and lysosomes fusion) represent some of the most critical polymorphisms associated with IAV infection, suggesting an ineffective virus clearance. Regarding inflammatory response genes, single nucleotide variants in IL1B, TNF, LTA IL17A, IL8, IL6, IRAK2, PIK3CG, and HLA complex are associated with altered phenotype in pro-inflammatory molecules, participating in IAV infection and the severest form of the disease.

IL-4/IL-13 remodeling pathway of COVID-19 lung injury

The COVID-19 fatality rate is high when compared to the H1N1pdm09 (pandemic Influenza A virus H1N1 subtype) rate, and although both cause an aggravated inflammatory response, the differences in the mechanisms of both pandemic pneumonias need clarification. Thus, our goal was to analyze tissue expression of interleukins 4, 13, (IL-4, IL-13), transforming growth factor-beta (TGF-β), and the number of M2 macrophages (Sphingosine-1) in patients who died by COVID-19, comparing with cases of severe pneumopathy caused by H1N1pdm09, and a control group without lung injury. Six lung biopsy samples of patients who died of SARS-CoV-2 (COVID-19 group) were used and compared with ten lung samples of adults who died from a severe infection of H1N1pdm09 (H1N1 group) and eleven samples of patients who died from different causes without lung injury (CONTROL group). The expression of IL-4, IL-13, TGF-β, and M2 macrophages score (Sphingosine-1) were identified through immunohistochemistry (IHC). Significantly higher IL-4 tissue expression and Sphingosine-1 in M2 macrophages were observed in the COVID-19 group compared to both the H1N1 and the CONTROL groups. A different mechanism of diffuse alveolar damage (DAD) in SARS-CoV-2 compared to H1N1pdm09 infections were observed. IL-4 expression and lung remodeling are phenomena observed in both SARS-CoV-2 and H1N1pdm09. However, SARS-CoV-2 seems to promote lung damage through different mechanisms, such as the scarce participation Th1/Th17 response and the higher participation of the Th2. Understanding and managing the aggravated and ineffective immune response elicited by SARS-CoV-2 merits further clarification to improve treatments propose.

A meta-analysis of tumor necrosis factor (TNF) gene polymorphism and susceptibility to influenza A (H1N1)

PURPOSE

The aim of the study was to comprehensively evaluate the associations between tumor necrosis factor (TNF) gene polymorphism and influenza A (H1N1) susceptibility.

METHODS

The relevant studies were identified through a search of PubMed, Embase, and Cochrane library database until February 29, 2020, without language restrictions. Two independent reviewers extracted the data, and any discrepancies were resolved by consensus. The quality of the eligible article was evaluated by Newcastle-Ottawa Quality Assessment Scale (NOS). Egger's test was applied to evaluate publication bias. All these analyses were performed using Stata15.1 software.

RESULTS

A total of 5 studies with 474 cases and 805 controls were included. The results of meta-analysis showed that there were statistically significant for rs361525 in allelic model (A vs. G) [OR = 2.46 (1.10, 5.52)] and for rs1800750 in dominant model (AA + GA vs. GG) [OR = 2.42 (1.24, 4.71)] in cases vs. controls. Furthermore, subgroup analysis for race showed that for rs361525 in allelic model (A vs. G), there were significant differences for Caucasian [OR = 3.64 (1.18, 11.23)] and no significant difference for Mexican [OR = 2.25 (0.82, 6.13)] in cases vs. controls. There was publication bias for rs361525 in dominant model (AA + GA vs. GG, p = 0.042) and rs1800629 in recessive model (AA vs. GG + GA, p < 0.001).

CONCLUSIONS

Caucasian with A site mutation of -238TNF G/A (rs361525) was more susceptible to influenza A (H1N1).The -376 dominant model AA + GA of TNF genes was associated with the susceptibility to influenza A (H1N1). However, more studies with large sample size are needed to confirm the results.

Glycolytic and immunological alterations in human U937 monocytes in response to H1N1 infection

We monitored changes that took place in glycolytic enzymes, the pyruvate end product of glycolysis, tumor necrosis factor α (TNFα), and toll-like receptors (TLRs) both at the transcriptional and translational levels upon direct interaction between PR8-H1N1 and the human monocytes U937 in vitro system. U937 were first treated with H1N1 infectious viral particles or phorbol-12-myristate-13-acetate (PMA) or left untreated and later infected with the H1N1 virus. Levels of phosphofructokinase 1 (PFK1) and pyruvate were biochemically quantified. In addition, levels of TNFα, TLR3, and TLR7 were measured by ELISA. The transcriptional profiles of PFKs, inflammatory cytokines, TLR3 and TLR7 were relatively quantified by qRT-PCR. The results generally revealed significant changes in both the transcriptional and translational profiles of the studied biochemical and immunological parameters upon influenza infection in a time-dependent manner. In conclusion, H1N1 infection triggers transcriptional and translational changes in immortalized human monocytes, which might serve as markers for infection subject for further validation for their specificities.

Hypercytokinemia and Pathogen-Host Interaction in COVID-19

Severe acute respiratory syndrome (SARS) coronavirus (CoV)-2 (SARS-CoV-2) is a novel coronavirus identified as the cause of coronavirus disease-2019 (COVID-19) that began in Wuhan, China in late 2019 and spread now in 210 countries and territories around the world. Many people are asymptomatic or with mild symptoms. However, in some cases (usually the elderly and those with comorbidities) the disease may progress to pneumonia, acute respiratory distress syndrome and multi-organ dysfunction that can lead to death. Such wide interindividual differences in response to SARS-CoV-2 infection may relate to several pathogen- and host-related factors. These include the different levels of the ubiquitously present human angiotensin I converting enzyme 2 (ACE2) receptors gene expression and its variant alleles, the different binding affinities of ACE2 to the virus spike (S) protein given its L- and S-subtypes and the subsequent extent of innate immunity-related hypercytokinemia. The extensive synthesis of cytokines and chemokines in coronavirus diseases was suggested as a major factor in exacerbating lung damage and other fatal complications. The polymorphisms in genes coding for pro-inflammatory cytokines and chemokines have been associated with mediating the response and susceptibility to a wide range of infections and their severe outcomes. Understanding the nature of pathogen-host interaction in COVID-19 symptomatology together with the role of hypercytokinemia in disease severity may permit developing new avenues of approach for prevention and treatment and can delineate public health measures to control the spread of the disease.

The role of Tumor necrosis factor alpha −308 G>A promoter polymorphism in pediatric community acquired pneumonia

Background

Tumor necrosis factor alpha (TNF-α) −308 G>A promoter polymorphism might be associated with excessive production of the proinflammatory cytokine TNF-α, modulating host response to pulmonary infections. Our objective was to evaluate the association of TNF-α gene −308 G>A polymorphism with susceptibility to, and severity of, community-acquired pneumonia (CAP).

Results

This was a cross-sectional study including 45 Egyptian children hospitalized for CAP in addition to 45 healthy children who served as a control group. Pneumonia severity was assessed on admission by the World Health Organization (WHO) guidelines; Pediatric Respiratory Severity Score (PRESS) score; Predisposition, Infection, Response and Organ failure (PIROm) score; and Respiratory Index of Severity in Children (RISC) score. Genotyping of TNF-α polymorphism was performed to all individuals by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Patients were monitored till hospital discharge. Frequency of AG genotype was lower among patients compared with control [odds ratio (OR) and 95% confidence interval (CI) = 0.13 (0.03–0.63); p = 0.012]. Prevalence of genotypes AA+AG was lower among patients compared with controls [OR and 95% CI = 0.34 (0.12–0.99); p = 0,048]. The “A” allele prevalence was higher among controls, but no significant association was found with CAP [OR and 95% CI = 0.58 (0.25–1.35); p = 0.21]. When PRESS score was used to classify patients into “severe pneumonia” and “non-severe pneumonia,” no significant association of any of the alleles or genotypes with CAP severity was found.

Conclusion

TNF-α −308 G>A polymorphism confers protection from pediatric CAP but is not associated with indicators of CAP severity. Larger studies are needed to confirm these findings in pediatric patients from different ethnicities.

Influenza A (H1N1) virus infection and TNF-308, IL6, and IL8 polymorphisms in Egyptian population: a case-control study

BACKGROUND

The importance of influenza is increasing mainly because of the appearance of novel pandemic strains such as swine and avian. Each year, influenza has spread around the world causing about 250,000-500,000 deaths and more than 5 million cases of severe illness.The objective is as follows: evaluating the outcomes of patients with influenza A (H1N1) virus in relation to certain TNF-308, IL6, and IL8 polymorphisms and identifying the associated factors with the severe outcome.

SUBJECT AND METHODS

This is a case-control study. The cases were patients confirmed by real-time polymerase chain reaction (RT-PCR) to be influenza A (H1N1) virus infected. The controls were healthy individuals. Medical history and outcome of the disease was registered. In all study participants, polymorphisms of TNF rs1800629, IL6 rs18138879, and IL8 rs4073; odds ratio (OR); and the 95% confidence interval (95% CI) were calculated.

RESULTS

Infection with influenza A (H1N1) virus was associated more with the following genotypes: TNF-308 AA (OR = 4.041; 95% CI = 1.215-13.4) and IL8 AA (OR = 3.273; 95% CI = 1.372-7.805). According to our study results, HCV (OR = 3.2, 95% CI 1.2-8.5), renal disease (OR = 3.4, 95% CI 0.9-13.6), cancer (OR = 3.1, 95% CI 0.3-31.1), TB (OR = 8.4, 95% CI 1.8-39.7), ICU (OR = 2.9, 95%1.2-7.1), and mortality (OR = 7.9, 95% CI 0.9-67.4) are considered as risk factors for influenza A (H1N1)-infected patients.

CONCLUSIONS

Our findings concluded that TNF-308 (AA) and IL8 (AA) polymorphisms may increase the susceptibility to be infected with H1N1influenza virus.

Association of polymorphisms in inflammatory cytokines encoding genes with severe cases of influenza A/H1N1 and B in an Iranian population

Background

The increased levels of blood cytokines is the main immunopathological process that were attributed to severe clinical outcomes in cases of influenza A, influenza B and people with influenza-like illness (ILI). Functional genetic polymorphisms caused by single nucleotide polymorphisms (SNPs) in inflammatory cytokines genes can influence their functions either qualitatively or quantitatively, which is associated with the possibility of severe influenza infections. The aim of the present case-control study was to investigate the association of polymorphisms in inflammatory cytokines genes with influenza patients and ILI group in an Iranian population.

Methods

Total number of 30 influenza B, 50 influenza A (H1N1) and 96 ILI inpatient individuals were confirmed by Real-time RT-PCR and HI assays. The genotype determination was assessed for defined SNPs in IL-1β, IL-17, IL-10 and IL-28 genes.

Results

The frequencies of the IL-1β rs16944 (P = 0.007) and IL-17 rs2275913 (P = 0.006) genotypes were associated with severe influenza disease, while the frequencies of IL-10 rs1800872 and IL-28 rs8099917 were not associated with the disease (P > 0.05). Also, the absence of A allele in IL-17 rs2275913 SNP increased the risk of influenza A (H1N1) infection (P = 0.008).

Conclusions

This study demonstrated that influenza A- (H1N1) and B-infected patients and also ILI controls have different profiles of immune parameters, and individuals carrying the specific cytokine-derived polymorphisms may show different immune responses towards severe outcome.

Cytokine Profiles of Severe Influenza Virus-Related Complications in Children

Rationale

Effective immunomodulatory therapies for children with life-threatening “cytokine storm” triggered by acute influenza infection are lacking. Understanding the immune profiles of children progressing to severe lung injury and/or septic shock could provide insight into pathogenesis.

Objectives

To compare the endotracheal and serum cytokine profiles of children with influenza-related critical illness and to identify their associations with severe influenza-associated complications.

Methods

Children with influenza-related critical illness were enrolled across 32 hospitals in development (N = 171) and validation (N = 73) cohorts (December 2008 through May 2016). Concentrations of 42 cytokines were measured in serum and endotracheal samples and clustered into modules of covarying cytokines. Relative concentrations of cytokines and cytokine modules were tested for associations with acute lung injury (ALI), shock requiring vasopressors, and death/ECMO.

Measurements and main results

Modules of covarying cytokines were more significantly associated with disease severity than individual cytokines. In the development cohort, increased levels of a serum module containing IL6, IL8, IL10, IP10, GCSF, MCP1, and MIP1α [shock odds ratio (OR) = 3.37, family-wise error rate (FWER) p < 10⁻⁴], and decreased levels of a module containing EGF, FGF2, SCD40L, and PAI-1 (shock OR = 0.43, FWER p = 0.002), were both associated with ALI, shock, and death-ECMO independent of age and bacterial coinfection. Both of these associations were confirmed in the validation cohort. Endotracheal and serum cytokine associations differed markedly and were differentially associated with clinical outcomes.

Conclusion

We identified strong positive and negative associations of cytokine modules with the most severe influenza-related complications in children, providing new insights into the pathogenesis of influenza-related critical illness in children. Effective therapies may need to target mediators of both inflammation and repair.

Seasonal influenza A/H3N2 virus infection and IL-1Β, IL-10, IL-17, and IL-28 polymorphisms in Iranian population

Increased blood cytokines is the main immunopathological process that were attributed to severe clinical outcomes in cases of influenza A/H3N2 virus infection. The study was aimed to investigate the polymorphisms of IL-1β, IL-10, IL-17, and IL-28 genes to find the possibility of their association with the clinical outcome of influenza A/H3N2 virus infection among the infected patients in Iran. This is a Case-Control study in which influenza A/H3N2 virus positive confirmed with real-time PCR were the cases. DNA samples from groups were genotyped for polymorphisms in rs16944 (IL-1β), rs1800872 (IL-10), rs2275913 (IL-17), and rs8099917 (IL-28). Confidence interval (95%CI) and Odds ratio (OR) were calculated. IL-17 rs2275913 (GG and AG) were associated with risk of infection with that were statistically significant (P < 0.05, OR = 2.08-2.94). IL-1β (rs16944) (GG) was associated with reduced risk of infection (P < 0.01, OR = 0.46). Genotype GG and GT of IL-10 (rs1800872) were associated with increased risk of infection with influenza A/H3N2 virus (P < 0.05, OR = 2.04-2.58). In addition, IL-28 (rs8099917) genotypes GG (P < 0.05, OR = 0.49) and TG (P < 0.05, OR = 0.59) were associated with reduced risk of ILI symptom while genotype TT (P < 0.01, OR = 4.31) was associated with increased risk of ILI symptom. The results of this study demonstrated that polymorphisms of genes involved in the inflammatory and anti-inflammatory process affect the outcome of disease caused by influenza A/H3N2 virus. Thorough insight on host immune response at the time of influenza A virus infection is required to ensure adequate patient care in the case of feature outbreaks. J. Med. Virol. 88:2078-2084, 2016. © 2016 Wiley Periodicals, Inc.

Genetic dissection of host immune response in pneumonia development and progression

The role of host genetic variation in pneumonia development and outcome is poorly understood. We studied common polymorphisms in the genes of proinflammatory cytokines (IL6 rs1800795, IL8 rs4073, IL1B rs16944), anti-inflammatory cytokines (IL10 rs1800896, IL4 rs2243250, IL13 rs20541) and toll-like receptors (TLR2 rs5743708 and rs4696480, TLR4 rs4986791, TLR9 rs352139, rs5743836 and rs187084) in patients with community-acquired pneumonia (CAP) (390 cases, 203 controls) and nosocomial pneumonia (355 cases, 216 controls). Experimental data were included in a series of 11 meta-analyses and eight subset analyses related to pneumonia susceptibility and outcome. TLR2 rs5743708 minor genotype appeared to be associated with CAP/Legionnaires’ disease/pneumococcal disease. In CAP patients, the IL6 rs1800795-C allele was associated with severe sepsis/septic shock/severe systemic inflammatory response, while the IL10 rs1800896-A allele protected against the development of these critical conditions. To contribute to deciphering of the above results, we performed an in silico analysis and a qualitative synthesis of literature data addressing basal and stimulated genotype-specific expression level. This data together with database information on transcription factors’ affinity changes caused by SNPs in putative promoter regions, the results of linkage disequilibrium analysis along with SNPs functional annotations supported assumptions about the complexity underlying the revealed associations.

TNF, IL6, and IL1B Polymorphisms Are Associated with Severe Influenza A (H1N1) Virus Infection in the Mexican Population

Background

Hypercytokinemia is the main immunopathological mechanism contributing to a more severe clinical course in influenza A (H1N1) virus infections. Most patients infected with the influenza A (H1N1) pdm09 virus had increased systemic levels of pro-inflammatory cytokines; including interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α). We propose that single-nucleotide polymorphisms (SNPs) in the promoter regions of pro-inflammatory genes are associated with the severity of influenza A (H1N1) pdm09 virus infection.

Methods

145 patients with influenza A (H1N1) (pA/H1N1), 133 patients with influenza-like illness (ILI), and 360 asymptomatic healthy contacts (AHCs) were included. Eleven SNPs were genotyped in six genes (TNF, LT, IL1B, IL6, CCL1, and IL8) using real-time PCR; the ancestral genotype was used for comparison. Genotypes were correlated with 27 clinical severity variables. Ten cytokines (GM-CSF, TNF-α, IL-2, IL-1β, IL-6, IL-8, IFN-γ, IL-10, IL-5, and IL-4) were measured on a Luminex 100.

Results

The IL6 rs1818879 (GA) heterozygous genotype was associated with severe influenza A (H1N1) virus infection (odds ratio [OR] = 5.94, 95% confidence interval [CI] 3.05–11.56), and two IL1B SNPs, rs16944 AG and rs3136558 TC, were associated with a decreased risk of infection (OR = 0.52 and OR = 0.51, respectively). Genetic susceptibility was determined (pA/H1N1 vs. AHC): the LTA rs909253 TC heterozygous genotype conferred greater risk (OR = 1.9), and a similar association was observed with the IL1B rs3136558 CC genotype (OR = 1.89). Additionally, severely ill patients were compared with moderately ill patients. The TNF-238 GA genotype was associated with an increased risk of disease severity (OR = 16.06, p = 0.007). Compared with ILIs, patients with severe pA/H1N1 infections exhibited increased serum IL-5 (p <0.001) and IL-6 (p  =  0.007) levels.

Conclusions

The TNF gene was associated with disease severity, whereas IL1B and IL6 SNPs were associated with influenza A (H1N1) virus infection.

Anti-inflammatory effect of thalidomide on H1N1 influenza virus-induced pulmonary injury in mice

The purpose of this study is to investigate the anti-inflammatory effect of thalidomide (Thd) on H1N1-induced acute lung injury in mice. BALB/C mice were infected intranasally with influenza A virus (H1N1) and then treated with Thd at a dose of 100 or 200 mg/kg/day for 7 days. Weight loss and survival of mice were monitored for 14 days after virus challenge, and the serum and lung tissues were collected at 4 days for histological and biochemical analysis. The results showed that Thd significantly improved the survival rate, reduced the infiltration of inflammatory cells and cytokine (e.g., IL-6, TNF-α) and chemokine (e.g., RANTES, IP-10) levels, and inhibited activated p-NFκB p65 in infected mice. These findings suggested that Thd may attenuate H1N1-induced pulmonary injury and thus may find use in the treatment of viral diseases.

Host genes and influenza pathogenesis in humans: an emerging paradigm

The emergence of the pandemic influenza virus A(H1N1)pdm09 in 2009 and avian influenza virus A(H7N9) in 2013 provided unique opportunities for assessing genetic predispositions to severe disease because many patients did not have any underlying risk factor or neutralizing antibody against these agents, in contrast to seasonal influenza viruses. High-throughput screening platforms and large human or animal databases from international collaborations allow rapid selection of potential candidate genes for confirmatory functional studies. In the last 2 years, at least seven new human susceptibility genes have been identified in genetic association studies. Integration of knowledge from genetic and phenotypic studies is essential to identify important gene targets for treatment and prevention of influenza virus infection.

TGF-β Blood Levels Distinguish Between Influenza A (H1N1)pdm09 Virus Sepsis and Sepsis due to Other Forms of Community-Acquired Pneumonia

There is a strong interest in finding adequate biomarkers to aid in the diagnosis and prognosis of influenza A (H1N1)pdm09 virus infection. In this study, serum levels of inflammatory cytokines and laboratory markers were evaluated to assess their usefulness as biomarkers of influenza A (H1N1)pdm09 and their association with fatal cases. Serum samples of consecutive patients with a clinical presentation suggestive of influenza A (H1N1)pdm09 and progression to sepsis were evaluated. Serum inflammatory cytokines and routine laboratory tests were performed and correlated with positivity for influenza A (H1N1)pdm09 influenza by real time reverse transcription polymerase chain reaction and the results of three clinical severity scores (Sequential Organ Failure Assessment [SOFA], CURB-65, and Acute Physiology and Chronic Health Evaluation II [APACHE II]). High SOFA scores and some of its individual components, but not CURB-65 or APACHE II scores, correlate with fatal cases regardless of etiology. Total and unconjugated bilirubin, Ca(++), Cl(-), prothrombin times, and partial thromboplastin times discriminate influenza A (H1N1)pdm09 from other causes of community-acquired pneumonia. High levels of IL-8, IL-10, and IL-17 were increased in influenza A (H1N1)pdm09 patients when compared with controls (p<0.05). IL-6 levels were significantly elevated in influenza A (H1N1)pdm09 patients and non-(H1N1)pdm09 patients when compared with controls (p<0.05). TGF-β serum levels discern between healthy controls, influenza A (H1N1)pdm09 patients, and patients with other causes of community-acquired pneumonia. TGF-β levels were negatively correlated with SOFA on admission in influenza A (H1N1)pdm09 patients. TGF-β levels are a useful tool for differentiating influenza A (H1N1)pdm09 from other causes of pneumonia progressing to sepsis.

Associations of three well-characterized polymorphisms in the IL-6 and IL-10 genes with pneumonia: a meta-analysis

Published data on the associations between three well-characterized polymorphisms in the interleukin 6 and 10 (IL-6 and IL-10) genes and the risk of pneumonia are inconclusive. A meta-analysis was performed to derive a more precise estimate. The electronic databases MEDLINE (Ovid) and PubMed were searched from the earliest possible year to May 2014. A total of 9 articles met the criteria, and these included 3460 patients with pneumonia and 3037 controls. The data were analyzed with RevMan software, and risk estimates are expressed as odds ratios (ORs) and 95% confidence intervals (95% CIs). Analyses of the full data set failed to identify any significant association of pneumonia risk with the IL-6 gene -174C allele (OR = 1.00; 95% CI: 0.98–1.03), the IL-10 gene -592C allele (OR = 1.20; 95% CI: 0.95–1.52), or the IL-10 gene -1082A allele (OR = 1.21; 95% CI: 0.99–1.49). In a subgroup analysis by pneumonia type, ethnicity, sample size and quality score, no significantly increased risk of pneumonia was found for individuals carrying the IL-6 gene -174C allele. There was a low probability of publication bias, as reflected by the fail-safe number. This meta-analysis suggests that there is no significantly increased risk of pneumonia associated with previously reported IL-6 and IL-10 polymorphisms.

Molecular analysis of serum and bronchoalveolar lavage in a mouse model of influenza reveals markers of disease severity that can be clinically useful in humans

BACKGROUND

Management of influenza, a major contributor to the worldwide disease burden, is complicated by lack of reliable methods for early identification of susceptible individuals. Identification of molecular markers that can augment existing diagnostic tools for prediction of severity can be expected to greatly improve disease management capabilities.

METHODOLOGY/PRINCIPAL FINDINGS

We have analyzed cytokines, proteome flux and protein adducts in bronchoalveolar lavage (BAL) and sera from mice infected with influenza A virus (PR8 strain) using a previously established non-lethal model of influenza infection. Through detailed cytokine and protein adduct measurements of murine BAL, we first established the temporal profile of innate and adaptive responses as well as macrophage and neutrophil activities in response to influenza infection. A similar analysis was also performed with sera from a longitudinal cohort of influenza patients. We then used an iTRAQ-based, comparative serum proteome analysis to catalog the proteome flux in the murine BAL during the stages correlating with "peak viremia," "inflammatory damage," as well as the "recovery phase." In addition to activation of acute phase responses, a distinct class of lung proteins including surfactant proteins was found to be depleted from the BAL coincident with their "appearance" in the serum, presumably due to leakage of the protein following loss of the integrity of the lung/epithelial barrier. Serum levels of at least two of these proteins were elevated in influenza patients during the febrile phase of infection compared to healthy controls or to the same patients at convalescence.

CONCLUSIONS/SIGNIFICANCE

The findings from this study provide a molecular description of disease progression in a mouse model of influenza and demonstrate its potential for translation into a novel class of markers for measurement of acute lung injury and improved case management.