Secretory Antibodies in Breast Milk Promote Long-Term Intestinal Homeostasis by Regulating the Gut Microbiota and Host Gene Expression.

ABSTRACT: Maintenance of intestinal homeostasis requires a healthy relationship between the commensal gut microbiota and the host immune system. Breast milk supplies the first source of antigen-specific immune protection in the gastrointestinal tract of suckling mammals, in the form of secretory immunoglobulin A (SIgA). SIgA is transported across glandular and mucosal epithelial cells into external secretions by the polymeric immunoglobulin receptor (pIgR). Here, a breeding scheme with pIgR-sufficient and -deficient mice was used to study the effects of breast milk-derived SIgA on development of the gut microbiota and host intestinal immunity. Early exposure to maternal SIgA prevented the translocation of aerobic bacteria from the neonatal gut into draining lymph nodes, including the opportunistic pathogen Ochrobactrum anthropi. By the age of weaning, mice that received maternal SIgA in breast milk had a significantly different gut microbiota from mice that did not receive SIgA, and these differences were magnified when the mice reached adulthood. Early exposure to SIgA in breast milk resulted in a pattern of intestinal epithelial cell gene expression in adult mice that differed from that of mice that were not exposed to passive SIgA, including genes associated with intestinal inflammatory diseases in humans. Maternal SIgA was also found to ameliorate colonic damage caused by the epithelial-disrupting agent dextran sulfate sodium. These findings reveal unique mechanisms through which SIgA in breast milk may promote lifelong intestinal homeostasis, and provide additional evidence for the benefits of breastfeeding. We used microarrays to determine the effects of passive and active secretory IgA, in the presence or absence of the epithelial-disrupting agent dextran sulfate sodium, on gene expression in intestinal epithelial cells of mice A breeding scheme was used that involved crosses between mouse dams and sires that were deficient or sufficient for expression of the polymeric immunoglobulin receptor (Pigr), a protein that is required for transport of secretory IgA (SIgA) into external secretions. Offspring of these crosses were genotyped for Pigr alleles, and littermate offspring were distributed into 4 groups based on early exposure to passive SIgA in mother's milk (P-yes and P-no) and ability to carry out Pigr-mediated endogenous transport of active SIgA (A-yes and A-no). Seventy-day-old gender-matched Pigr+/- and Pigr-/- offspring of Pigr+/- and Pigr-/- dams were left untreated or given 2% dextran sulfate sodium (DSS) in drinking water for 8 days. Colonic epithelial cells were isolated, and total cellular RNA was purified. RNA was pooled from 3 mice for each of 2 biological replicates for microarray analysis.

ORGANISM(S): Mus musculus

SUBMITTER: Charlotte Kaetzel 

PROVIDER: E-GEOD-54371 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress