Associations of polymorphisms in interleukins with tuberculosis: Evidence from a meta-analysis

Role of the IL8 rs4073 polymorphism in central nervous system toxicity in patients receiving multidrug-resistant tuberculosis treatment

OBJECTIVE

To determine the role of the IL8 rs4073 polymorphism in predicting the risk of central nervous system (CNS) toxicity in patients receiving standard pharmacological treatment for multidrug-resistant tuberculosis (MDR-TB).

METHODS

A cohort of 85 consenting MDR-TB patients receiving treatment with second-line antituberculosis drugs had their blood samples amplified for the IL8 (rs4073) gene and genotyped. All patients were clinically screened for evidence of treatment toxicity and categorized accordingly. Crude and adjusted associations were assessed.

RESULTS

The chief complaints fell into the following categories: CNS toxicity; gastrointestinal toxicity; skin toxicity; and eye and ear toxicities. Symptoms of gastrointestinal toxicity were reported by 59% of the patients, and symptoms of CNS toxicity were reported by 42.7%. With regard to the genotypes of IL8 (rs4073), the following were identified: AA, in 64 of the study participants; AT, in 7; and TT, in 11. A significant association was found between the dominant model of inheritance and CNS toxicity for the crude model (p = 0.024; OR = 3.57; 95% CI, 1.18-10.76) and the adjusted model (p = 0.031; OR = 3.92; 95% CI, 1.13-13.58). The AT+TT genotype of IL8 (rs4073) showed a 3.92 times increased risk of CNS toxicity when compared with the AA genotype.

CONCLUSIONS

The AT+TT genotype has a tendency to be associated with an increased risk of adverse clinical features during MDR-TB treatment.

Association of IL4RA and IL-8 polymorphism in predicting susceptibility towards tuberculosis

Mycobacterium tuberculosis is an infectious bacterial disease frequently affecting the lungs. With two fatalities from tuberculosis (TB) occurring every three minutes, India has the highest disease burden. The aetiology of tuberculosis has been linked to IL-8 and IL-4RA. Thus, the impact of the IL4RAQ576R and IL8 gene polymorphism on TB susceptibility was assessed. 301 healthy and 301 TB patients participated in a cross-sectional study. PCR RFLP was performed to identify the genotype of the IL4RAQ576R and IL-8 +781C/T gene polymorphism. The odds ratio and 95% confidence intervals were calculated using logistic regression to evaluate the risk of TB with IL4RAQ576R and IL-8 +781C/T polymorphism. A significant association was found between IL-4RA (p=0.04) and IL-8 +781 C/T (p= 0.03) in tuberculosis. Further, when clinical symptoms were compared with both polymorphisms, two of them, i.e., cough in IL-4RA576R (p=0.04) and breathlessness (p=0.01) in IL-8 +781C/T, showed a significant association. Moreover, different combinations of the SNPS were made, and the 3 risk allele shows a significant protective role (p=0.02). There is considerable evidence which shows that M. tuberculosis causes TB, an infectious disease that is genetically predisposed. The results of our study also showed that IL-4 RA Q576R and IL-8 +781 C/T played a significant protective function against tuberculosis, confirming the claim mentioned earlier. However, only the cough in IL-4RA576R and the dyspnea in IL-8 +781C/T exhibited a significant co-relation in TB patients when symptoms were examined. Additionally, the combined effects of the two SNPs were investigated, and it was discovered that the 3-risk allele has a strong association with tuberculosis. Therefore, the polymorphisms mentioned earlier, which may also be influenced by ethnicity, may significantly impact the chance of developing tuberculosis.

Association of IL6 and IL10 gene promotor polymorphisms with susceptibility to acute necrotizing encephalopathy

Objective

Acute necrotizing encephalopathy (ANE) is a severe complication of infectious diseases affecting the brain and systemic organs. The main pathogenesis is cytokine storm, in which interleukin-6 (IL-6) and interleukin-10 (IL-10) are candidates for key cytokines. To further elucidate their roles in the etiology and pathogenesis of ANE, we studied polymorphisms in the promotor regions of the IL6 and IL10 genes by genetic and functional analyses.

Methods

We first conducted a case-control association study of four IL6 and three IL10 polymorphisms. We genotyped 31 Japanese ANE cases and compared the results with those of approximately 200 Japanese controls. For the two polymorphisms showing a possible association, we next studied whether the polymorphisms alter the production of IL-6 or IL-10 by lymphoblasts upon phorbol 12-myristate 13-acetate (PMA) stimulation.

Results

The frequencies of IL6 rs1800796G allele and IL10 rs1800871/rs1800872 CC/CC diplotype were significantly higher in ANE cases than in controls. The IL10 CC/CC diplotype was associated with low IL-10 production, whereas the IL6 GG genotype was not associated with IL-6 production.

Conclusion

IL10 rs1800871/rs1800872 CC/CC diplotype may predispose Japanese children to ANE by altering IL-10 production in the early phase of infection. Etio-pathogenetic significance of IL6 rs1800796G remains to be elucidated.

Association between genetic variants in TREM1, CXCL10, IL4, CXCL8 and TLR7 genes with the occurrence of congenital Zika syndrome and severe microcephaly

Congenital Zika syndrome (CZS) is a cluster of malformations induced by Zika virus (ZIKV) infection and the underline mechanisms involved in its occurrence are yet not fully understood. Along with epidemiological and environmental factors, the genetic host factors are suggested as important to the CZS occurrence and development, however, few studies have evaluated this. This study enrolled a total of 245 individuals in a case-control association study compound a cohort of high specific interest constituted by 75 mothers who had delivered CZS infants, their 76 infants, and 47 mothers that had delivered healthy infants, and their 47 infants. Sixteen single-nucleotide polymorphisms on TREM1, CXCL10, IL4, CXCL8, TLR3, TLR7, IFNR1, CXCR1, IL10, CCR2 and CCR5 genes were genotyped to investigate their association as risk factors to CZS. The results show an association between C allele at TREM1 rs2234246 and C allele at IL4 rs224325 in mothers infected with ZIKV during pregnancy, with the increased susceptibility to CZS occurrence in their infants and the SNP CXCL8 rs4073 and the G allele at CXCL10 rs4508917 with presence of CZS microcephaly in the infants. Furthermore, the T allele at CXCL8 rs4073 and TRL7 rs179008 SNPs were associated with the severity of microcephaly in children with CZS. These results suggest that these polymorphisms in genes of innate immune responses addressed here are associated to increased risk of occurrence and severity of CZS in pregnant mothers infected with ZIKV and their CZS infants.

RNA-Seq Transcriptome Analysis of Peripheral Blood From Cattle Infected With Mycobacterium bovis Across an Experimental Time Course

Bovine tuberculosis, caused by infection with members of the Mycobacterium tuberculosis complex, particularly Mycobacterium bovis, is a major endemic disease affecting cattle populations worldwide, despite the implementation of stringent surveillance and control programs in many countries. The development of high-throughput functional genomics technologies, including RNA sequencing, has enabled detailed analysis of the host transcriptome to M. bovis infection, particularly at the macrophage and peripheral blood level. In the present study, we have analysed the transcriptome of bovine whole peripheral blood samples collected at −1 week pre-infection and +1, +2, +6, +10, and +12 weeks post-infection time points. Differentially expressed genes were catalogued and evaluated at each post-infection time point relative to the −1 week pre-infection time point and used for the identification of putative candidate host transcriptional biomarkers for M. bovis infection. Differentially expressed gene sets were also used for examination of cellular pathways associated with the host response to M. bovis infection, construction of de novo gene interaction networks enriched for host differentially expressed genes, and time-series analyses to identify functionally important groups of genes displaying similar patterns of expression across the infection time course. A notable outcome of these analyses was identification of a 19-gene transcriptional biosignature of infection consisting of genes increased in expression across the time course from +1 week to +12 weeks post-infection.

Association of IL-4 rs2243250 polymorphism with susceptibility to tuberculosis: A meta-analysis involving 6794 subjects

BACKGROUND

Interleukin-4 (lL-4) is a critical negative cytokine in tuberculosis (TB) immune process, acting through modulating macrophages activation and Th1/Th2 balance. rs2243250 has been demonstrated to be associated with enhanced promoter strength in IL-4 expression. We performed a meta-analysis to assess the association between IL-4 rs2243250 polymorphism and TB risk.

METHODS

We identified relevant studies by a comprehensive search of PubMed, Web of Science, and Embase databases, published up to February 10, 2021. The pooled odds ratios (ORs) and its 95% confidential intervals (95%CIs) were used to evaluate the associations under five genetic models. All statistical analyses were conducted with STATA 12.0 software.

RESULTS

Totally 11 qualified studies involving 3097 TB cases and 3697 controls were enrolled in this meta-analysis. Overall, we didn't detect any significant association between IL-4 rs2243250 polymorphism and TB risk (T vs. C: OR = 1.05, 95% CI = 0.85-1.30, p = 0; 65; TT + TC vs. CC: OR = 1.05, 95% CI = 0.73-1.50, p = 0.81; TT vs. TC + CC: OR = 1.10, 95% CI = 0.81-1.50, p = 0.54; TT vs. CC: OR = 1.17, 95% CI = 0.71-1.94, p = 0.54; TC vs. CC: OR = 1.03, 95% CI = 0.73-1.45, p = 0.88). Significant heterogeneity was identified in analyses under all genetic models. However, in the subgroup of European population, the recessive model provided an OR of 2.54 (1.30-4.96), with no significant between-study heterogeneity.

CONCLUSION

In conclusion, our meta-analysis indicated that IL-4 rs2243250 may increase TB risk in European population in recessive genetic model. Further research is needed to clarify the cause of ethnic difference in genetic association study.

Polymorphism in the IL-1β promoter is associated with IgG antibody response to circumsporozoite protein repeats of Plasmodium vivax

BACKGROUND

It is well established that infection by Plasmodium vivax is a result of host-parasite interactions. In the present study, association with the IL1/IL2 cytokine profiles, anticircumsporozoite protein antibody levels and parasitic loads was evaluated in individuals naturally infected with P. vivax in an endemic area of the Brazilian Amazon.

METHODS

Molecular diagnosis of P. vivax and variants was performed using the PCR-RFLP method and IL1B -511C>T, IL2 -330T>G and IL2+114T>G polymorphisms were identified using PCR-RFLP and allele-specific PCR. IL-1β and IL-2 cytokine levels were detected by flow cytometry and circumsporozoite protein (CSP) antibodies were measured by ELISA.

RESULTS

Three variants of P. vivax CSP were identified and VK247 was found to be the most frequent. However, the prevalence and magnitude of IgG antibodies were higher for the VK210 variant. Furthermore, the antibody response to the CSP variants was not associated with the presence of the variant in the infection. Significant differences were observed between the single nucleotide polymorphism (SNP) -511T>C in the IL1B gene and levels of antibodies to the VK247 and P. vivax-like variants, but there were no associations between SNPs in IL1 and IL2 genes and their plasma products.

CONCLUSIONS

Individuals with the rs16944 CC genotype in the IL1β gene have higher antibody levels to the CSP of P. vivax of VK247 and P. vivax-like variants.