ALLERGY |
New York, NY
ABSTRACT
Taylor AL, Hale J, Wiltschut J, Lehmann H, Dunstan JA, Prescott SL. Clin Exp Allergy. 2006;36:1227–1235
PURPOSE OF THE STUDY. To determine if probiotic dietary supplementation in the first 6 months of life could modify allergen- and vaccine-specific immune responses.
STUDY POPULATION. One hundred seventy-eight term infants born to women with a history of allergic disease and a positive prick-skin test result were enrolled in Australia between July 2002 and March 2005.
METHODS. In a randomized double-blind, placebo-controlled design, 3 x 109 colony-forming units of Lactobacillus acidophilus (LARVI-A1; Probiomics, Eveleigh, New South Wales, Australia) was administered daily to term infants for the first 6 months of life. Peripheral blood mononuclear cell cytokine responses to tetanus toxoid (TT), house dust mite (HDM), ovalbumin, ß-lactoglobulin, Staphylococcus enterotoxin B, and phytohemagglutinin were measured at 6 months of age.
RESULTS. Of the 178 infants who completed the study, blood samples were available from 118 children (60 placebo treated, 58 probiotic treated). Infants treated with probiotics had significantly lower interleukin 10 (IL-10) production to TT vaccine antigen than those in the placebo group (P = .03). Infants treated with probiotics had no significant differences in the levels of T-helper 1 and T-helper 2 cell responses to foods (ovalbumin or ß-lactoglobulin) or inhalant allergens (HDM). However, the number of infants who had detectable tumor necrosis factor
and IL-10 responses to HDM were less than those who had received probiotics (P = .046 and 0.014, respectively). In addition, children who received probiotics had decreased productions of IL-5 and transforming growth factor ß in response to Staphylococcus enterotoxin B (P = .044 and 0.015, respectively).
CONCLUSIONS. Although there were no consistent effects on allergen-specific responses, children treated with probiotics may have immunomodulatory effects on TT responses. The clinical ramifications of this have yet to be determined.
REVIEWER COMMENTS. It is interesting to note that the TT vaccine-specific responses in IL-10 were significant, whereas the allergen-specific responses were not. However, the clinical implication of this is not known. The authors pointed out that the types of probiotics selected and dosing regimen may be important in regard to immunologic outcomes. Some studies have shown a protective effect of probiotic supplementation on outcomes of atopic dermatitis (some have not), and the effect on allergen-specific responses, if any, remains unclear. This study began to tease out the allergen-specific outcomes. Although clinical atopic dermatitis evaluations were not made during this study, the immunologic effects of probiotics in infants with a maternal history of atopy are seemingly not allergen specific.