Relationship of maternal skin test responses to infant cord-blood progenitor cytokine receptor expression

Abstract

Rationale Increasingly, focus has turned toward the perinatal period as critical for development of atopy and atopic disease. Based on previous findings of impaired cord blood T helper-cell (Lancet 1999;353:196) and CD34+ progenitor maturational responses (J Allergy Clin Immunol 1999;104:370) in atopic at-risk infants, we examined the relationship between maternal atopy, as measured by the number of positive skin prick tests (SPT), and cytokine receptor expression on CD34+ cord blood progenitors. Methods Patients from two separate cohorts were examined – the Allergy Prevention Program cohort from Australia and a small, ongoing birth cohort from Hamilton, Ontario. CD34+/CD45+ cord blood mononuclear cells were analyzed using flow cytometry for IL-3, IL-5 and GM-CSF receptor expression. Maternal SPT were performed to standard allergen extracts. Results Data available on 64 subjects (6 from Hamilton, 58 from Australia) revealed a significant inverse relationship between GM-CSFRα and IL-5Rα and the number of positive maternal SPT in both cohorts: Hamilton cohort r=−0.857 ( P=0.029); Australian cohort r=−0.293 ( P=0.026). In the Hamilton cohort, a positive correlation was found between IL-3Rα and positive maternal SPT r=0.848 ( P=0.033). Conclusions Infant cord blood progenitor IL-5Rα and GM-CSFRα are negatively associated with the number of maternal SPT, while IL-3Rα is positively associated with SPT. These findings are consistent with the concept of a relative immaturity of hemopoietic progenitors in the cord blood of infants at risk of developing atopy, and point out the potential predictive capacity of cord blood progenitors for atopic disease