Interleukin-12 peripheral blood levels in asthmatic children.

: Interleukin-12 (IL-12) was measured in 45 asthmatic children aged 3 to 16 years. The assessments were performed on 20 children during an episode of acute exacerbation and on 25 children during remission. There was no significant difference between the mean IL-12 level during exacerbation (1.63 +/- 2.08 pg/mL) and during remission (0.88 +/- 0.56 pg/mL) (p = .83). A positive, but insignificant, correlation was found between forced expiratory volume in 1 second and IL-12 (p = .634). IL-12 levels were significantly lower in children with a positive family history of asthma (1.13 +/- 1.78 pg/mL) compared with those without (1.31 +/- 1.06 pg/mL) (p < .012), supporting the theory that the gene-environment interactions affect the immune responses. IL-12 peripheral blood levels had no detectable impact on the course of established asthma in the study population.