One of the child’s caretakers (usually the mother) completed a questionnaire slightly modified from one used in the Collaborative Study of the Genetics of Asthma(14 (link)) containing questions about demographics, the child’s general and respiratory health, family history of asthma, breastfeeding, environmental tobacco smoke (ETS), and outdoor physical activity. Height and weight were measured to the nearest centimeter and kilogram, respectively. Dietary data were collected using a semi-quantitative food frequency questionnaire (FFQ) adapted from one developed and validated to measure intake of 75 food items in Costa Ricans(15 (link)).
Fifteen circulating TH17 pathway-related cytokines (IL-1b, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon-γ, soluble CD40 ligand, and tumor necrosis factor-α) were measured in plasma samples using Bio-Plex Pro Human TH17 cytokine panel on the BioPlex HTF system (Bio-Rad Laboratories Inc., Hercules, CA). Assays were designed on magnetic beads in a capture-sandwich immunoassay format. Levels are presented as pg/mL. Undetectable cytokine levels were assigned a constant (half the lowest limit of detection). All cytokine levels were log-transformed for data analysis.
Fifteen circulating TH17 pathway-related cytokines (IL-1b, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon-γ, soluble CD40 ligand, and tumor necrosis factor-α) were measured in plasma samples using Bio-Plex Pro Human TH17 cytokine panel on the BioPlex HTF system (Bio-Rad Laboratories Inc., Hercules, CA). Assays were designed on magnetic beads in a capture-sandwich immunoassay format. Levels are presented as pg/mL. Undetectable cytokine levels were assigned a constant (half the lowest limit of detection). All cytokine levels were log-transformed for data analysis.