gms | German Medical Science

Introduction: Toll-like Receptors (TLR) are key players in innate immunity. Because the expression of TLR2 and TLR4 is increased in chronic rhinosinusitis they could play an important role in this disease. It is known that the different expression of SNPs (Single Nucleotide Polymorphisms) of the TLRs can influence the individual predisposition for immunological diseases. Since the promoter region of each gene is crucial for its activation and expression, we investigated a SNP of the promoter region of TLR2 (rs 4696480) in patients with chronic rhinosinusitis with nasal polyps (CRS+NP) and in healthy controls. Furthermore, we analyzed 9 additional SNPs on exon 3 of the TLR2-gene, for which a relation to atopic diseases has been described.

Methods: Samples of 134 patients (CRS+NP n= 87, controls n=47) were analyzed. DNA was obtained from tissue samples or blood. After amplification, direct sequencing of the promoter region and exon 3 of TLR2 was performed.

Results: The expression variants of SNP rs 4696480 in the promoter region or the TLR2-gene in patients with CRS+NP did not differ significantly in relation to controls (Chi-square-test: p=0.998), and to the published normal distribution in the caucasian population (Chi-square-test: p=0.338). The analysis of the SNPs in exon 3 - including R753Q also revealed no significant differences.

Conclusion: Neither the expression variants of the investigated SNPs in the promoter region nor on exon 3 of TLR2 seem to be associated to a predisposition to chronic rhinosinusitis with nasal polyps. It is unlikely that these SNPs are related to the increased expression of TLR2 in these patients.