Prolonged exclusive breast-feeding results in low serum concentrations of immunoglobulin G, A and M

PKU-related dysgammaglobulinaemia: the effect of diet therapy on IgE and allergic sensitization

The effect of diet on the development of immunoallergic signs and symptoms in children with phenylketonuria (PKU) was evaluated. Immunological indices of 58 children with PKU treated with diets were compared to the immunological indices of 58 healthy (non-PKU) children. In the PKU group, 39 children had been placed on diet therapy within the first month of life; 19 children had been placed on diet therapy after 6 months of age. Total circulating lymphocytes; CD3+, CD4+, CD8+ circulating lymphocytes; and serum IgA, IgM, IgG and total IgE levels were measured for each child. Skin prick tests were performed for common inhalant and food allergens. Every 3 months over the 2-year period of this study, the signs and symptoms of eczema, allergic rhinitis and asthma were recorded. The PKU group had lower IgG levels (p = 0.004) and higher total IgE levels (p = 0.0001) than the control group. Significantly lower IgE levels were found in children started on diet therapy within the first month of life compared with those started on diet therapy after 6 months of age (p = 0.0001). Allergic sensitization was significantly more frequent in the PKU group (24/58 vs 13/58, z = 2.00, p < 0.05), but no significant difference in the incidence of eczema and allergic rhinitis was found. Asthma was less frequent in the PKU group than in the control group (5/58 vs 14/58, z = 2.09, p < 0.05). Thus, diet appeared to prevent the development of immunoallergic signs and symptoms.

[The immunogenicity and allergenicity of an experimental cow's milk protein hydrolysate]

Recently hydrolyzed cow milk proteins have been introduced for the production of infant formulas and are available as hypoallergenic infant formulas. To achieve a decrease in antigenicity and allergenicity a protein hydrolysis (mostly enzymatic) is performed. Sera of different groups were tested for IgG and IgE antibody-binding: 31 controls, 36 atopic children, and 20 children with cow milk protein allergy. Histamine release from basophil leucocytes after incubation with the cow milk proteins beta-lactoglobuline and casein, as with the cow milk protein hydrolysate, was determined additionally for five control, 10 atopic, and five cow milk allergic children. IgG binding to cow milk protein and to the hydrolysate was found in the majority of the sera tested. IgE binding was detectable in sera of only five of the 10 cow milk allergic children, despite detection of specific IgE-antibodies against cow milk proteins in all sera. Histamine release by the cow milk hydrolysate was observed for five atopic and two cow milk allergic children. The cow milk hydrolysate demonstrated a decreased but partially conserved antigenic/allergenic potency compared with cow milk proteins.