Defective tumour necrosis factor-alpha production in mother's milk is related to cow's milk allergy in suckling infants

Background The precise role of leucocytes in human milk is still unresolved . Objective To assist in clarifying the immune mechanisms involved in the dev elopment of CMA in suckling infants, we studied the role of immunoregulator y leucocytes and their mediators in human breast milk. Methods The study population consisted of 43 lactating mothers and their in fants, aged 0.25-8.0 months, followed-up prospectively from birth. Of these mothers, 27 had an infant with challenge-proven cow's milk allergy manifes ted with either skin (n = 23), gastrointestinal (n = 2) or skin and gastroi ntestinal symptoms (n = 3). Sixteen mothers with a healthy infant served as controls. We evaluated the spontaneous and mitogen-induced tumour necrosis factor-alpha (TNF alpha) and interferon-gamma (IFN gamma) production of hu man milk leucocytes and isolated peripheral blood lymphocytes in vitro with a commercial ELISA kit. Results TNF alpha production of breast milk leucocytes was significantly lo wer in the mothers with a cow's milk-allergic infant, whereas IFN gamma pro duction of these cells was comparable in the two groups. Conclusion Our results suggest that in the breast milk of mothers having an infant with cow's milk allergy, the number and function of TNF alpha-produ cing cells is defective. This might lead to a disturbance in the developmen t of oral tolerance and thereby to the development of CMA in suckling infan ts. These novel results may help in clarifying the etiopathogenesis of CMA.