Clin. Vaccine Immunol.
doi:10.1128/CVI.00070-08
Copyright (c) 2008, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.
Influence of Host IL-10 Polymorphisms on the Development of Travelers' Diarrhea due to Heat Labile producing Enterotoxigenic Escherichia coli in US Travelers to Mexico
Jose Flores,
Herbert L. DuPont,
Stephanie A. Lee,
Jaime Belkind-Gerson,
Mercedes Paredes,
Jamal A. Mohamed,
Lisa Y. Armitige,
Dong-Chuan Guo,
and
Pablo C. Okhuysen*
The University of Texas at Houston, Medical School, Texas; St. Luke's Episcopal Hospital, Houston, Texas; The University of Texas at Houston, School of Public Health, Texas; Instituto Nacional de Salud Pública, México; Baylor College of Medicine
* To whom correspondence should be addressed. Email:
Pablo.c.okhuysen{at}uth.tmc.edu.
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Abstract |
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Background. Up to 60% of US visitors to Mexico develop travelers' diarrhea (TD), mostly due to Escherichia coli that produce heat labile (ETEC-LT) and/or heat stable (ETEC-ST) enterotoxins. Distinct single nucleotide polymorphisms (SNPs) within the IL-10 promoter have been associated with high, intermediate, or low production of IL-10.
Objective. We conducted a prospective study to investigate the association of SNPs in the IL-10 promoter and the occurrence of travelers' diarrhea in ETEC-LT exposed travelers.
Methods. Sera from US travelers to Mexico collected on arrival and departure was studied for ETEC-LT seroconversion. Pyrosequencing was performed to genotype IL-10 SNPs. Subjects were also studied for other enteropathogens in case of diarrhea.
Results. 121 of 569 (21.3%) travelers seroconverted to ETEC-LT, and among them 75 (62%) developed diarrhea. Symptomatic seroconversion was more commonly seen in subjects who carried a high IL-10 producing genotype; -1082 GG 83% vs. AA 54% (p 0.02), -819 CC 71% vs. TT 33% (p 0.005), -592 CC 71% vs. AA 38% (p 0.02). Travelers with the haplotype GCC were more likely to have symptomatic seroconversion than those with the ATA haplotype (71% vs. 38%, p 0.002).
Conclusions. Travelers genetically predisposed to produce high IL-10 were more likely to experience symptomatic ETEC TD.