Division of Infectious Diseases, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
Liver Transpl. 2011 Sep;17(9):1081-8. doi: 10.1002/lt.22327.
Toll-like receptor 2 (TLR2) is an immune sensor for gram-positive bacterial cell wall components. Single-nucleotide polymorphisms (SNPs) in the TLR2 gene that impair its function may, therefore, influence the risk and outcomes of gram-positive bacterial infections. In a cohort of 694 liver transplant recipients, we assessed the TLR2 SNP that is translated into an amino acid substitution of arginine for glutamine at position 753 (R753Q), and we found that its presence was associated with the clinical characteristics and outcomes of gram-positive bacterial infections. The proportions of patients with the TLR2 R753Q SNP did not significantly differ between those with gram-positive bacterial infections and those without gram-positive bacterial infections (9.6% versus 9.6%, P = 0.999). However, in patients with the TLR2 R753Q SNP, higher rates of infection recurrence (27.8% versus 11.8%, P = 0.07) and initial septic shock (11.1% versus 1.2%, P = 0.047) were observed. Chronic hepatitis C [relative risk (RR) = 3.37, 95% confidence interval (CI) = 1.24-9.13, P = 0.02], initial septic shock (RR = 15.13, 95% CI = 2.84-80.54, P = 0.001), and central venous catheter-related bacteremia (RR = 7.22, 95% CI = 2.54-20.51, P < 0.001) were significantly associated with 90-day all-cause mortality after gram-positive bacterial infections. In contrast, the presence of the TLR2 R753Q SNP was not significantly associated with mortality.
Toll 样受体 2（TLR2）是革兰阳性菌细胞壁成分的免疫传感器。TLR2 基因中的单核苷酸多态性（SNP）如果损害其功能，可能会影响革兰阳性菌感染的风险和结局。在 694 例肝移植受者队列中，我们评估了 TLR2 基因中导致第 753 位精氨酸突变为谷氨酰胺的 SNP（R753Q），发现其存在与革兰阳性菌感染的临床特征和结局相关。携带 TLR2 R753Q SNP 的患者在发生革兰阳性菌感染和未发生革兰阳性菌感染的患者之间的比例无显著差异（9.6%比 9.6%，P = 0.999）。然而，在携带 TLR2 R753Q SNP 的患者中，感染复发率（27.8%比 11.8%，P = 0.07）和初始感染性休克发生率（11.1%比 1.2%，P = 0.047）较高。慢性丙型肝炎（相对危险度 [RR] = 3.37，95%置信区间 [CI] = 1.24-9.13，P = 0.02）、初始感染性休克（RR = 15.13，95%CI = 2.84-80.54，P = 0.001）和中心静脉导管相关性菌血症（RR = 7.22，95%CI = 2.54-20.51，P < 0.001）与革兰阳性菌感染后 90 天全因死亡率显著相关。相反，TLR2 R753Q SNP 的存在与死亡率无显著相关性。
