Interaction of orally administered Lactobacillus rhamnosus GG with skin and gut microbiota and humoral immunity in infants with atopic dermatitis.
BACKGROUND
The intestinal mucosa functions as a defence barrier against gut intraluminar antigens. The maturational events in the gut parallel its step-wise colonization. Atopic dermatitis (AD) is associated with aberrant barrier functions of the skin epithelium and, in a subgroup of patients, of the gut mucosa.


OBJECTIVE
To investigate the interaction of Lactobacillus rhamnosus GG (LGG) with skin and gut microbiota and humoral immunity in infants with AD.


METHODS
Thirty-nine infants with AD were randomized for a 3-month period in a double-blind design to receive extensively hydrolysed casein formula supplemented with (n=19) or without (n=20) LGG (ATCC 53103) 5.0 × 10⁷ CFU/g to achieve a daily intake of 3.4 × 10⁹ CFU. Sampling (blood and fecal samples, cotton swab from the skin) was carried out at entry, 1 and 3 months thereafter. Ig-secreting cells were determined by enzyme-linked immunospot and the proportions of CD19(+)CD27(+) B cells among peripheral blood leucocytes by flow cytometry. The major groups of gut and skin bacteria were characterized using PCR.


RESULTS
The proportions of IgA- and IgM-secreting cells decreased significantly in the treated group; the baseline-adjusted ratios for treated vs. untreated at 1 month were 0.59 (95%CI 0.36-0.99, P=0.044) for IgA- and 0.53 (95%CI 0.29-0.96, P=0.036) for IgM-secreting cells. The proportions of CD19(+)CD27(+) B cells increased in the probiotic-treated infants but not in the untreated. There were no significant differences in bifidobacterial species composition of the gut between the study groups. On the skin, the bacterial counts of Bifidobacterium genus vs. Clostridium coccoides in the treated and untreated infants were similar.


CONCLUSIONS
Specific probiotics may enhance gut barrier function and aid in the development of immune responses. Thus, specific probiotics may afford protection against offending macromolecules in the gut and provide control for future infections by accelerated immunological maturation (ClinicalTrials.gov ID NCT01148667).
Department of Pediatrics, Turku University Central Hospital, Turku, Finland. merja.nermes@tyks.fi
M
M
Nermes
J M
JM
Kantele
T J
TJ
Atosuo
S
S
Salminen
E
E
Isolauri
D000284:Administration, Oral; D016175:B-Lymphocyte Subsets / Q000276:immunology; D002469:Cell Separation; D003876:Dermatitis, Atopic / Q000276:immunology*; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D056724:Immunity, Humoral / Q000187:drug effects / Q000276:immunology; D007223:Infant; D041943:Infant Formula / Q000737:chemistry; D007413:Intestinal Mucosa / Q000187:drug effects / Q000382:microbiology*; D052201:Lacticaseibacillus rhamnosus / Q000276:immunology*; D016133:Polymerase Chain Reaction; D019936:Probiotics / Q000008:administration & dosage*; D012867:Skin / Q000187:drug effects / Q000382:microbiology*