LSTM Home > LSTM Research > LSTM Online Archive

Environmental conditions, immunologic phenotypes, atopy, and asthma: New evidence of how the hygiene hypothesis operates in Latin America

Figueiredo, Camila Alexandrina, Amorim, Leila D., Alcantara-Neves, Neuza M., Matos, Sheila M.A., Cooper, Philip, Rodrigues, Laura C. and Barreto, Mauricio L. (2013) 'Environmental conditions, immunologic phenotypes, atopy, and asthma: New evidence of how the hygiene hypothesis operates in Latin America'. Journal of Allergy and Clinical Immunology, Vol 131, Issue 4, pp. 1064-1068.

Full text not available from this repository.

Abstract

Background

It has been proposed that improved hygiene and reduced experience of infections in childhood influences the development of allergic diseases. The mechanisms by which the hygiene operates are not well established but are underpinned by two apparently incompatible immunologic paradigms, the balance of TH1 versus TH2 cytokines and IL-10–mediated regulation of TH2 cytokines.

Objective

This study defined immunologic phenotypes with the use of latent class analysis and investigated their associations with environmental factors, markers of allergy and asthma, in a Latin American population.

Methods

We studied 1127 children living in urban Brazil. Data on wheeze and environmental exposures were collected with standardized questionnaires. Atopy was measured by specific IgE in serum and skin prick test reactivity to aeroallergens. Cytokines were measured in culture after the stimulation of peripheral blood leukocytes with mitogen. Infections with pathogens were assessed by serology and stool examinations. Children were classified as having high or low burden of infection. Latent class analysis was used to identify immune phenotypes on the basis of cytokine production. Logistic regression was used to evaluate the adjusted effects of environment and burden of infection on the immunologic phenotypes and the effect of the phenotypes on atopy and asthma.

Results

Three phenotypes were identified, labeled underresponsive, intermediate, and responsive. Children of more educated mothers, living in improved environmental conditions, and with a low burden of infection were significantly more likely to have the responsive phenotype. The responsive phenotype was significantly associated with an increased prevalence of atopy but not asthma.

Conclusion

Our findings contribute to a better understanding of the immune mechanisms by which the hygiene hypothesis operates in urban Latin America.

Item Type: Article
Subjects: QU Biochemistry > Genetics > QU 500 Genetic phenomena
QW Microbiology and Immunology > Reference Works. General Immunology > QW 520 Research (General)
WA Public Health > WA 30 Socioeconomic factors in public health (General)
WD Disorders of Systemic, Metabolic or Environmental Origin, etc > Disorders and Injuries of Environmental Origin > WD 600 General works
WF Respiratory System > WF 140 Diseases of the respiratory system (General)
Faculty: Department: Biological Sciences > Parasitology Department
Digital Object Identifer (DOI): https://doi.org/10.1016/j.jaci.2013.01.016
Depositing User: Lynn Roberts-Maloney
Date Deposited: 20 Feb 2015 10:13
Last Modified: 06 Feb 2018 13:09
URI: http://archive.lstmed.ac.uk/id/eprint/4928

Statistics

View details

Actions (login required)

Edit Item Edit Item