Revisiting the Heterogeneous IFN-γ Response of Bacille of Calmette-Guérin (BCG)-Revaccinated Healthy Volunteers in a Randomized Controlled Trial: Effect of the Body Mass Index and of the IFNG+874 A/T Polymorphism

Elisabete L Conceição; Francisco S Nascimento-Sampaio; Paulo A Schwingel; Evelin S Oliveira; Michael S Rocha; Igor Vieira; Carlos M C Mendes; Adelmir Souza-Machado; Martha M Oliveira; Manoel Barral-Netto; Jamocyr M Marinho; Theolis Barbosa

doi:10.1371/journal.pone.0160149

Revisiting the Heterogeneous IFN-γ Response of Bacille of Calmette-Guérin (BCG)-Revaccinated Healthy Volunteers in a Randomized Controlled Trial: Effect of the Body Mass Index and of the IFNG+874 A/T Polymorphism

PLoS One. 2016 Jul 29;11(7):e0160149. doi: 10.1371/journal.pone.0160149. eCollection 2016.

Authors

Elisabete L Conceição^{1

2}, Francisco S Nascimento-Sampaio¹, Paulo A Schwingel¹, Evelin S Oliveira^{1

2}, Michael S Rocha², Igor Vieira^{2

3}, Carlos M C Mendes¹, Adelmir Souza-Machado¹, Martha M Oliveira⁴, Manoel Barral-Netto^{1

2}, Jamocyr M Marinho^{3

5}, Theolis Barbosa^{1

2}

Affiliations

¹ Universidade Federal da Bahia, Salvador, BA, Brazil.
² Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, BA, Brazil.
³ Escola Bahiana de Medicina e Saúde Pública, Salvador, BA, Brazil.
⁴ Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
⁵ Hospital Santa Izabel, Salvador, BA, Brazil.

Abstract

In trials evaluating the immune responses to Bacille of Calmette-Guérin (BCG), the genetic background and the nutritional status are host-related factors that could affect the heterogeneity in these parameters. The IFNG+874 A/T (rs 62559044) polymorphism has been reported to influence the IFN-γ production by BCG-vaccinated individuals challenged in vitro with mycobacterial antigens. The body mass index (BMI) is a proxy for the nutritional status and has been associated both with the susceptibility to tuberculosis and with the IFN-γ response. We show that although the IFNG+874 A/T polymorphism was not associated with the heterogeneity of IFN-γ production in a randomized controlled trial that evaluated long-term immune responses to BCG revaccination previously conducted in Salvador, Bahia, Brazil, the effect of this polymorphism on the observed increase in IFN-γ production among revaccinated subjects was adjusted in individuals with a low BMI.

MeSH terms

BCG Vaccine / administration & dosage*
Body Mass Index*
Brazil
Healthy Volunteers
Humans
Immunization, Secondary*
Interferon-gamma / biosynthesis*
Interferon-gamma / genetics
Multivariate Analysis
Polymorphism, Genetic*

Substances

BCG Vaccine
Interferon-gamma

Grants and funding

This work was supported by Fundacao de Amparo a Pesquisa do Estado da Bahia—FAPESB (002/03-PPP). ELC received a scholarship from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior—CAPES. ESO and MSR received scholarships from FAPESB. TB was a senior investigator from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico—CNPq. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.