title: Low doses of allergen and probiotic supplementation separately or in combination alleviate allergic reactions to cow β-lactoglobulin in mice.
abstract: Probiotic supplementation and oral tolerance induction can reduce certain types of food allergy. The objectives of this study were to investigate the allergy-reducing effects of probiotics (VSL#3) and/or oral tolerance induction via low doses of an allergen supplementation in β-lactoglobulin (BLG)-sensitized mice. Three-week-old, male BALB/c mice were divided into 6 groups (n = 8/group): sham-sensitized negative control (CTL-), BLG-sensitized positive control (CTL+), oral tolerance-induced and BLG-sensitized group (OT), probiotic-supplemented OT group (OTP), probiotic-supplemented CTL- (PRO), and probiotic-supplemented and BLG-sensitized (PROC) groups. Mice were i.p. sensitized with BLG and alum and then orally challenged with BLG. Immunological responses were assessed by monitoring hypersensitivity scores and measuring levels of BLG-specific serum Igs, total serum IgE and fecal IgA, and cytokines from serum and spleen lysates. Hypersensitivity scores were significantly lower in the PROC (2.00 ± 0.53), OT (0.75 ± 0.46), and OTP mice (1.00 ± 0.53) than in the CTL+ mice (2.63 ± 0.52) as were BLG-specific serum IgE concentrations (34.3 ± 10, 0.442 ± 0.36, 3.54 ± 3.5, and 78.5 ± 8.7 μg/L for PROC, OT, OTP, and CTL+, respectively). Our results suggest that supplementation of VSL#3 suppressed the allergic reaction mainly through increased intestinal secretary IgA (sIgA) in PROC mice, and oral tolerance offered allergen-specific protective effects to BLG-induced allergy, probably through CD4+CD25+ regulatory T cell-mediated active suppression. In OTP mice, probiotics did not induce a further reduction of hypersensitivity score compared with OT mice but may provide additional protection to unforeseen nonspecific challenges through increased intestinal sIgA.
authors.affiliation: Department of Animal Science, Macdonald Campus, McGill University, Ste Anne de Bellevue, Quebec, Canada.
authors.forename: Cin L
authors.initials: CL
authors.lastname: Thang
authors.forename: Joyce I
authors.initials: JI
authors.lastname: Boye
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000284:Administration, Oral; D000485:Allergens / Q000008:administration & dosage* / Q000627:therapeutic use; D000818:Animals; D002417:Cattle; D016207:Cytokines / Q000097:blood / Q000378:metabolism; D005243:Feces / Q000737:chemistry; D007108:Immune Tolerance; D007071:Immunoglobulin A, Secretory / Q000032:analysis; D007073:Immunoglobulin E / Q000032:analysis; D007413:Intestinal Mucosa / Q000276:immunology / Q000378:metabolism; D007782:Lactoglobulins / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016269:Milk Hypersensitivity / Q000097:blood / Q000276:immunology / Q000503:physiopathology / Q000517:prevention & control*; D019936:Probiotics / Q000627:therapeutic use*; D012720:Severity of Illness Index; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D014886:Weaning
chemical_list: D000485:Allergens; D016207:Cytokines; D007071:Immunoglobulin A, Secretory; D007782:Lactoglobulins; D007073:Immunoglobulin E