Association of TOLLIP mRNA Expression and TOLLIP rs5743899A/G, TOLLIP rs3750920C/T, and IL-10 -1082G/A Single-Nucleotide Polymorphisms with Susceptibility to Tuberculosis.

The early innate host immune response is crucial in the susceptibility to tuberculosis (TB). This study aimed to investigate the potential role of Toll-interacting protein (TOLLIP), a negative regulator of the human innate immune response, and interleukin-10 (IL-10), an anti-inflammatory cytokine, in susceptibility to TB. The peripheral blood mononuclear cells of 30 active pulmonary TB patients and 30 healthy volunteers were included. TOLLIP mRNA expression levels, single nucleotide polymorphisms (SNPs) of the TOLLIP gene, such as rs5743899A/G and rs3750920C/T, and IL-10 -1082G/A SNP were detected using real-time PCR, PCR-restriction fragment length polymorphism (PCR-RFLP) and amplification refractory mutation system-PCR (ARMS-PCR), respectively. TOLLIP mRNA expression levels were significantly higher in TB patients than in healthy controls (expression fold difference = 2.72, the delta-delta Ct method, also known as the 2-∆∆Ct method). The heterozygous (GA) genotype of the IL-10 -1080G/A polymorphism was significantly predominant among the patient group (p = 0.02, Hardy-Weinberg equilibrium). However, the Kruskal‒Wallis analysis found no significant relationship between TOLLIP mRNA expression levels and SNPs. TOLLIP mRNA and IL-10 -1082G/A SNP were assessed as potential biomarkers to predict TB susceptibility. For more significant results, they should be examined with other negative regulators of innate immunity and other immune factors associated with susceptibility to TB. Our study is the first to investigate the association of TOLLIP polymorphisms and expression levels with TB susceptibility in Turkey.