Predictive Factors for Atopy in Human Cord Blood

Several reports have claimed that there is a greater risk for a child with an atopic mother to develop allergy as compared to a child without a family history of atopy. High genetic risk of atopy in infants is associated with attenuated interferon gamma (IFNγ) responses. Cytokine responses have been detected in cord blood mononuclear cells (CBMC) after stimulation with bacterial antigens, suggesting allergen priming already in utero. Several methods have been used to identify neonates at risk of developing atopy for application of more effective preventive programs. The aim of this study was to measure the level of interferon gamma and interleukin-4 as a reflection of T-helper 1 (Thl) and T-helper 2 (Th2) cells, respectively, in both high and low risk neonates to find a new and accurate method for prediction of atopy. This study incuded 20 full term pregnant women and their neonates. They were divided into 2 groups: group A with 10 atopic mothers and their neonates and group B or control group with 10 pregnant mothers and their neonates with no family history of atopy. Maternal peripheral blood (PBMC) mononuclear cells as well as cord blood mononuclear cells (CBMC) were separated and cultured with Lipopolysaccharides and staphy- lococcal enterotoxin E, then IFNγ and IL-4 produced by Thl and Th2 cells, respectively, were measured by flow cytometry. The mean level of Thl expressing IFNy was significantly lower in atopic than non atopic mothers as well as their neonates. While mean level of Th2 cells expressing IL-4 were higher in both atopic mothers and their neonates. Our results suggest that there is a stronger Th2 bias after in vitro stimu- lation of CBMC from neonates with atopic heredity. Our conclusion as obtained from analysis of results was that perinatal T cell responses with their expressed cytokines could be accurately used as predictive markers for atopy especially interferon gamma.