Introduction
Environmental exposure and maternal status during pregnancy have a great impact on a child’s health and susceptibility to diseases from childhood until adulthood.1 Nutrition, pollution, microbiome, and other environmental factors that interact with the genetic background can reshape the fetal genetics and epigenetics.2,3 These genetic and epigenetic factors can leave long-term influences on a patient’s immunological, cardiovascular, and other systemic functioning and can lead to diseases later in life.4,5 Many birth cohort studies have investigated the link between perinatal exposure and the outcomes of atopic diseases in an attempt to identify possible predictive biomarkers.6,7
Fas and Fas ligand (FasL) interaction is an important pathway in inducing apoptosis. However, soluble Fas ligand, cleaved from the membrane-formed Fas ligand by matrix metalloproteinases, participates in the inflammatory reactions of rheumatic and allergic diseases.8,9 The concentration of soluble FasL in blood and bronchial lavage fluid has been noted to increase in asthmatic and allergic patients, especially during the allergy season.10,11 Soluble FasL in cord blood has been associated with atopic dermatitis in children.12 In this Prediction of Allergies in Taiwanese Children (PATCH) birth cohort study, we measured the soluble FasL concentration in cord blood and investigated its association with allergic outcomes and lung function in 7-year-old children.