Association of Interleukin 18, Interleukin 2, and Tumor Necrosis Factor Polymorphisms with Subacute Sclerosing Panencephalitis

Abstract

Subacute sclerosing panencephalitis (SSPE) is a progressive inflammatory and degenerative disorder of the central nervous system. The measles virus (MV) and host and environmental factors are involved in the development of SSPE, but the precise mechanism by which the MV causes SSPE is still unknown. Studies have indicated that in SSPE patients, specific polymorphisms of certain genes are most likely involved in impairing the host's ability to eradicate the MV. The purpose of our study was to elucidate the role of polymorphisms in the genes encoding interleukin (IL)-2, IL-18, and tumor necrosis factor alpha (TNF-α) in the development of SSPE. Using the polymerase chain reaction with sequence-specific primers, the single-nucleotide polymorphisms (SNPs) of the promoter regions of IL-2 (-330), TNF-α (-308), and IL-18 (-137 and -607) were studied in 54 patients with SSPE and 72 healthy controls. The frequency of SSPE patients with the AA genotype of IL-18 at position -607 was significantly higher than the frequency of those with the CC genotype (p<0.001, odds ratio [OR]: 5.76), and a significantly higher proportion of patients had the C allele at -137 compared with the controls (p=0.002, OR: 2.72). In a haplotype analysis of two SNPs in the IL-18 gene, the frequency of the CA haplotype was significantly higher in SSPE patients (p<0.001, OR: 3.99) than in the controls. The IL-2 (-330) and TNF-α (-308) polymorphisms revealed no significant differences. In conclusion, these data suggest that the IL-18 gene polymorphisms at position -607 and -137 might be genetic risk factors for the SSPE disease.

Subacute sclerosing panencephalitis

“…Variability in the global incidence of SSPE also indicates that genetic factors are involved. Many case‐control studies (mostly done in Turkey and Japan) observed genetic defects in components of innate immunity, including Toll‐like receptors and cytokines …”

Tumor necrosis factor (TNF) alpha and interleukin (IL) 18 genes polymorphisms are correlated with susceptibility to HPV infection in patients with and without cervical intraepithelial lesion

“…Five SNPs in the promoter region of IL18 gene (11q22.2-q22.3) have been described: -656 G/T, -607 C/A, -137 G/C, 113 G/T and 127 C/T (Giedraitis et al, 2001). However, only the SNPs at positions -137 G/C and -607 C/A were confirmed as having an impact on the activity of IL18 gene in previous studies (Piskin et al, 2013).…”

Advances in Antiviral Therapy for Subacute Sclerosing Panencephalitis

“…Moreover, some studies have reported associations between SSPE and single nucleotide polymorphisms (SNPs) of genes in the host immune system. These include SNPs in genes related to innate immunity such as MxA [41], tolllike receptor 3 (TLR3) [42], and TLR4 [43], and in those related to acquired immunity such as interleukin-2 (IL2) [44], IL4 [45], IL17 [43], IL18 [46], granzyme B (GZMB) [47], and programmed cell death 1 (PDCD1) [48]. Quantitative or qualitative differences in immune response to the measles virus caused by these SNPs may be related to disease susceptibility to SSPE.…”