Abstract
Background: This study aimed to investigate whether short-term probiotics-containing yogurt ingestion benefits to systemic cellular and humoral immunity in healthy schoolchildren. Methods: Healthy schoolchildren aged 4-12 years without major systemic or allergic history were studied. Subjects had diarrheal diseases or taken antibiotics within one month were also excluded. The Ethical Committee of our institute has approved our study design (ER-98-050). All of them have provided the serum samples before and after 4-week ingestion of probiotics-containing yogurt. The serum samples were tested for the TNF-α, IL-17, IL-10, IL-6, Immunoglobulin (Ig) A, G, and E levels. Results: A total of 60 children completing at least 80% consumption of total designed amount of yogurt were enrolled. Their mean age was 9.3±1.6 years with a female to male ratio 0.54. For systemic cytokines production, yogurt ingestion significantly decreased serum IL-6 level (12.8±4.2 vs. 24.2±6.3 pg/ml, P = 0.002) and marginal significantly increased TNF-α (66.4±14.6 vs. 44.5±10.9 pg/ml, P = 0.11). For immunoglobulin levels, children consumed yogurt can significantly increase serum IgA level (178.8±8.2 vs. 167.1±7.9 mg/dl, P = 0.001). However, yogurt consumption did not affect the levels of IL-17, IL-10, IgG, and IgE. Conclusions: Short-term probiotics-containing yogurt ingestion benefits on an increment of serum IgA and decrease of IL-6 levels in healthy schoolchildren.