Tantisira, K., Klimecki, W. T., Lazarus, R., Palmer, L. J., Raby, B. A., Kwiatkowski, D. J., Silverman, E., Vercelli, D., Martinez, F. D., & Weiss, S. T. (2004). Toll-like receptor 6 gene (TLR6): single-nucleotide polymorphism frequencies and preliminary association with the diagnosis of asthma. Genes and immunity, 5(5), 343-6.
Toll-like receptor 6 (TLR6) is one of a series of highly conserved innate immune receptors. We resequenced TLR6 in DNA samples from 24 African Americans, 23 European Americans, and 24 Hispanic Americans, identifying 53 SNPs, 22 with an allele frequency >5%. Significant differences in SNP frequencies among the three populations were noted. In all, 11 SNPs caused amino-acid changes, including one with a frequency >5% in all three populations. Utilizing this SNP (Ser249Pro), we performed exploratory nested case-control disease-association studies, including one involving 56 African Americans with asthma and 93 African American controls. The minor allele of this SNP was associated with decreased risk for asthma (odds ratio 0.38, 95% CI 0.16-0.87, P=0.01), an effect consistent with the known biology of the toll-like receptors. Although replication of this finding in other, larger samples is needed, variation in TLR6 may have relevance to the pathogenesis of immunologically mediated diseases.
LeVan, T. D., Guerra, S., Klimecki, W., Vasquez, M. M., Lohman, I. C., Martinez, F. D., Halonen, M., & Wright, A. L. (2006). The impact of CD14 polymorphisms on the development of soluble CD14 levels during infancy. Genes and Immunity, 7(1), 77-80.
PMID: 16395394;Abstract:
CD14 is a receptor involved in the recognition of lipopolysaccharide and other bacterial wall components that may be involved in the balance between infectious and allergic disease and the early polarization towards TH1. Our group has shown an association between polymorphisms in the 5′ flanking region of the CD14 gene and plasma soluble CD14 (sCD14) levels at 11 years of age. However, whether this association is present at birth and in infancy remains to be determined. In this study, we measured sCD14 levels in plasma from the umbilical cord (n = 387) and at 3 months (n = 357) and 1 year (n=312) of age in non-selected healthy infants to assess their relationship with CD14 genotypes at -4190, -2838, -1720 and -260 (relative to translation start site). There was no relation of CD14 genotypes with sCD14 at birth. However, there was a significant association between CD14 genotypes and sCD14 as early as 3 months. Longitudinal analysis suggests that CD14 polymorphisms modulate sCD14 levels up to 1 year of age. This association early in life may have an impact on TH1 polarization and subsequent protection against allergic disease. © 2006 Nature Publishing Group All rights reserved.
Bolt, A. M., Zhao, F., Pacheco, S., & Klimecki, W. T. (2012). Arsenite-induced autophagy is associated with proteotoxicity in human lymphoblastoid cells. Toxicology and Applied Pharmacology, 264(2), 255-261.
PMID: 22959463;PMCID: PMC3462290;Abstract:
Epidemiological studies of arsenic-exposed populations have provided evidence that arsenic exposure in humans is associated with immunosuppression. Previously, we have reported that arsenite-induced toxicity is associated with the induction of autophagy in human lymphoblastoid cell lines (LCL). Autophagy is a cellular process that functions in the degradation of damaged cellular components, including protein aggregates formed by misfolded or damaged proteins. Accumulation of misfolded or damaged proteins in the endoplasmic reticulum (ER) lumen causes ER stress and activates the unfolded protein response (UPR). In an effort to investigate the mechanism of autophagy induction by arsenite in the LCL model, we examined the potential contribution of ER stress and activation of the UPR. LCL exposed to sodium arsenite for 8-days induced expression of UPR-activated genes, including CHOP and GRP78, at the RNA and the protein level. Evidence for activation of the three arms of the UPR was observed. The arsenite-induced activation of the UPR was associated with an accumulation of protein aggregates containing p62 and LC3, proteins with established roles in the sequestration and autophagic clearance of protein aggregates. Taken together, these data provide evidence that arsenite-induced autophagy is associated with the generation of ER stress, activation of the UPR, and formation of protein aggregates that may be targeted to the lysosome for degradation. © 2012 Elsevier Inc.
Flores, R., Papenfuss, M., Klimecki, W. T., & Giuliano, A. R. (2006). Cross-sectional analysis of oncogenic HPV viral load and cervical intraepithelial neoplasia. International Journal of Cancer, 118(5), 1187-1193.
PMID: 16152619;Abstract:
In human papillomavirus (HPV)-associated carcinogenesis, HPV infection characteristics such as viral load may play an important role in lesion development. The purpose of this study was to determine the association between quantitative assessment of oncogenic HPV viral load, and abnormal cytology among women residing along the United States-Mexico border. A cross-sectional study of 2,319 women was conducted between 1997 and 1998. Viral load of oncogenic HPV types (16, 18, 31, 39, 45, 51, 52, and 58) was measured among 173 HPV (+) women using quantitative real-time PCR. Overall, HPV 16, 31, 52 and 58 showed the highest viral load. Single type infection had higher viral loads compared to multiple type infections. HPV viral load declined significantly (p = 0.04) with age. No significant association was observed with other known HPV risk factors such as oral contraceptive use, parity, sexual and STD history. Viral load was independently associated with degree of cervical lesions. An adjusted odds ratio (AOR) of 4.7 for the association between increasing total viral load and Atypical Squamous Cells of Undetermined Significance (ASCUS)/Atypical Glandular Cells of Undetermined Significance (AGUS) was observed (p for trend 0.01). Increased risk of low-grade SIL was observed with higher viral load compared with HPV negative women (AOR = 47.7 for total viral load; AOR = 37.1 for HPV viral load not including HPV16, and AOR = 25.9 for HPV16 viral load). Likewise, increased risk of high-grade SIL with higher viral loads was observed (AOR = 58.4 for high total viral load compared with HPV negative women, AOR = 58.1 for HPV viral load not including HPV16, and AOR = 69.8 for HPV16 high viral load). Results from this study suggest a dose-response relationship between increasing oncogenic HPV viral load and risk of LSIL and HSIL. © 2005 Wiley-Liss, Inc.
Yu, L., Martinez, F. D., & Klimecki, W. T. (2004). Automated high-throughput sex-typing assay. BioTechniques, 37(4), 662-4.