Passive exposure to smoke results in defective interferon-gamma production by adenoids in children with recurrent respiratory infections.
There is evidence that exposure to passive smoke is associated with an increased susceptibility to respiratory infections. Indeed, cigarette smoke extracts may interfere with the immune system, even though the precise mechanism has not been fully understood yet. Recurrent respiratory infections may be sustained by a defective immune response. The aim of the present study was to evaluate whether, in a cohort of children presenting both with recurrent respiratory infections and with a history of exposure to tobacco smoke, these factors were related to a lower local production of interferon-gamma (IFN-gamma) when compared to a similar non-exposed population. The study group included 128 children undergoing adenoidectomy, presenting with more than three respiratory infections per year, independently of exposure to passive smoke at home. The intracellular cytokine profile of lymphocyte subsets in adenoids was evaluated by flow cytometry analysis. Children exposed to tobacco smoke suffered from a significantly greater number of respiratory infections and had a lower percentage of IFN-gamma-producing CD8+ cells in adenoids than non-exposed children, while other T-cell subsets were not affected. The effect of smoke exposure seems to be specific to the IFN-gamma-producing CD8+ cells in adenoids and may contribute to the increased susceptibility to the recurrence of respiratory infections.
Marseglia
Gian Luigi
GL
Department of Paediatric Sciences, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. gl.marseglia@smatteo.pv.it
Avanzini
Maria Antonietta
MA
Caimmi
Silvia
S
Caimmi
Davide
D
Marseglia
Alessia
A
Valsecchi
Chiara
C
Poddighe
Dimitri
D
Ciprandi
Giorgio
G
Pagella
Fabio
F
Klersy
Catherine
C
Castellazzi
Anna Maria
AM
D000234:Adenoids / Q000276:immunology* / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D002465:Cell Movement; D002469:Cell Separation; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D004198:Disease Susceptibility; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism*; D008297:Male; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
D014028:Tobacco Smoke Pollution; D007371:Interferon-gamma