Effect of Peptidoglycan on Umbilical Cord Blood-Derived Basophils From Maternal With Allergic Asthma

Objective To determine if basophils harvested from neonates genetically predisposed to atopic disease had different levels of Toll-like receptors (TLR)2 expression and investigate whether putative TLR2 ligands mediated cytokine secretion. Methods Blood samples were collected from 12 asthmatic and 16 healthy women and their newborns. Informed consent was obtained from all participates. TLR2 expression was determined by using nucleic acid hybridization in situ and flow cytometry. IL-4 levels were quantified by ELISA following peptidoglycan (PGN) stimulation. Results TLR2 expression at the protein level and mRNA level were up-regulated in cord blood basophils from neonates born to mothers with allergic asthma following stimulation with PGN. Basophils purified from the cord blood of neonates born to atopic mothers produced more IL-4 compared to basophils purified from children born to non-atopic controls(P<0.01). Conclusion These data TLR2-mediated innate immune responses play a role in augmenting allergic reactions via modulation of basophil cytokine secretion. Microbial components may activate basophils through TLR2 (especially for genetically predisposed infants) to release cytokines associated with an increased incidence of allergic diseases. Key words: allergic asthma; basophil; Toll-like receptor-2; peptidoglycan; interleukin-4