Maternal allergy influences the proliferation of neonatal T cells expressing CCR4, CXCR5 or CD103

Summary Background Elevated proliferative response to allergen in cord blood mononuclear cells (CBMCs) is related to subsequent allergy development of the neonate and has been suggested as a screening marker for high allergy risk. Objective To characterize the proliferating cells in CBMCs from a neonatal group influenced by maternal allergy compared with a control group without known allergic heredity. Methods CBMCs were stimulated with bovine β‐lactoglobulin (β‐LG) and proliferation was analysed by radioactive thymidine incorporation and expressed both as the traditional stimulation index (SI) and SI corrected by eliminating non‐specific proliferation. After β‐LG combined with endotoxin stimulation, cellular expression of IL‐4 and IFN‐γ mRNA was determined by quantitative RT‐PCR and adhesion as well as chemokine receptors were analysed by three‐colour flow cytometry in proliferating T cells (CD3 + Ki‐67 + ). Results The percentage of CCR4 + cells correlated weakly with concurrent IL‐4 expression ( r S =0.5, P <0.05), while CXCR3 correlated strongly with IFN‐γ expression ( r S =0.83, P <0.001). In the allergy risk group, the percentage of proliferating T cells expressing CCR4 or integrin α E (CD103) was significantly reduced compared with the control group, while CXCR5 and the corrected SI were relatively increased (CCR4: P =0.01; integrin α E : P =0.03; CXCR5: P =0.04; SI: P =0.04). Conclusion Our results implied delayed maturation of immune functions involved in cellular migration, cell–cell interaction and immunoregulatory functions in neonates with hereditary allergy risk. The alterations observed in this subject group suggested that the corrected SI as well as proliferation of CCR4 + , CXCR5 + or CD103 + T cells in allergen‐stimulated CBMCs might serve as early screening markers for allergy risk.