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TLR1 and TLR6 Polymorphisms Are Associated with Susceptibility to Invasive Aspergillosis after Allogeneic Stem Cell Transplantation

Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York, United States
Annals of the New York Academy of Sciences (Impact Factor: 4.31). 12/2005; 1062(1):95-103. DOI: 10.1196/annals.1358.012
Source: PubMed

ABSTRACT Toll-like receptors (TLRs) transmit signals in response to Aspergillus fumigatus conidia and hyphae. In this preliminary study, we examined the association between single nucleotide polymorphisms (SNPs) in TLR1, TLR4, and TLR6 genes and development of invasive aspergillosis (IA) in 127 allogeneic hematopoietic stem cell transplant recipients consisting of 22 patients with IA and 105 unaffected control subjects. The following SNPs and their pairwise interactions were considered in the model: TLR1 (239G > C, 743A > G, 914A > T, 1805G > T), TLR4 (896A > G, 1196C > T), and TLR6 (359T > C, 745C > T, 764C > T). No association was found between donor SNP and the risk of IA. Analysis of recipient SNP data showed that the presence of TLR1 239G > C (Arg80 > Thr) or the presence of both TLR1 743A > G (Asn248 > Ser) and TLR6 745C > T (Ser249 > Pro) is associated with IA (odds ratio = 1.30, 95% confidence interval = 1.13 to 1.50; P < .001). Further analyses using a prospective cohort may enable us to identify TLR polymorphisms associated with the susceptibility to IA within a defined interval among immunocompromised patients.

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    • "Another study in Germany found a weak association of the TLR6 Ser249Pro SNP and asthma, however this association was lost after Bonferroni correction [166]. In single studies the TLR6 Ser249Pro SNP has been linked with susceptibility to infection with aspergillosis [167] and women homozygous for the 249Ser allele were found to have thinner left ventricular posterior walls as well as possessing monocytes responding weakly to the TLR6 ligand zymosan [168]. "
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    • "Gene SNPs or haplotypes Effect Disease Outcome References TLR1 R80T, N248S, I602S Reduced cytokine production by PBMCs in vitro Invasive aspergillosis, C. albicans systemic infections Susceptibility Kesh et al., 2005; Plantinga et al., 2012 TLR3 +95C/A Failure to activate CD8 + T-cell response Invasive aspergillosis Susceptibility Carvalho et al., 2012b L412F Decreased TLR3 functionality Chronic mucocutaneous candidiasis Susceptibility Nahum et al., 2011 TLR4 D299G/T399I Predicted to impair ligand binding Invasive aspergillosis, A. fumigatus, CCPA, C. albicans systemic infections Susceptibility Van Der Graaf et al., 2006; Bochud et al., 2008; Carvalho et al., 2008; De Boer et al., 2011 TLR6 S249P Unknown Invasive aspergillosis Susceptibility Kesh et al., 2005 TLR9 T-1237C "
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    • "Nevertheless, we cannot assume that TLR1 or TLR6 polymorphisms that lead to alteration in receptor function are impacting TLR2 recognition and activation. There is evidence that TLR1 and TLR6 polymorphism do exist in humans that affect responses to infectious diseases (especially mycobacteria ; Kesh et al., 2005; Bhide et al., 2009; Shey et al., 2010). However, for sake of clarity, this review will not address TLR1 or TLR6 polymorphisms and will only focus on TLR2 polymorphisms. "
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