Immune profiling of breast milk from mothers with treated celiac disease

Background The protective effect of breastfeeding on celiac disease (CD) onset is controversial. We studied a wide range of milk components in milk produced by celiac mothers following long-term gluten-free diet (GFD) in comparison to milk produced by healthy mothers. Methods Breast-milk samples from celiac (n = 33) and healthy (n = 41) mothers were obtained during the first year of lactation. A panel of bioactive components was analyzed by enzyme-linked immunosorbent assay in the aqueous fraction. We studied molecules involved in defenses, immunoregulation, and strengthening of the gut-epithelial barrier. Results During late lactation (from 6 to 12 months after delivery), the content of total immunoglobulin A (IgA) and IgM was significantly lower in the milk produced by celiac patients. Nevertheless, gliadin (GFD)-specific IgA relative contribution was higher in this group, in contrast to tetanus toxoid-specific antibodies. The balance between pro-inflammatory and anti-inflammatory molecules was different. While interleukin-6, tumor necrosis factor-alpha, and monocyte chemoattractant protein-1 were most frequently found in samples from celiac mothers, soluble Toll-like receptor-2 prevalence was lower. Conclusions We describe differences between the innate and adaptive immune profile of milk produced by celiac and healthy mothers. These results might explain previous controversial reports about breastfeeding and CD protection. Impact In spite of a long-term adherence to GFD, the milk produced by mothers with CD exhibit a different immune profile, in relation with some immunoregulatory factors and antibody content. This work shows a more comprehensive characterization of milk from celiac mothers, including macronutrients, lysozymes, growth factors, and immunoregulatory components that had not been studied before. The present study widens the available data regarding the characteristics of human milk of celiac mothers following GFD. Further follow-up studies of the health of children who were breastfed by celiac mothers will be necessary in order to also estimate the impact of the present results therein.

Automated summary

The study found differences in the immune profile of breast milk produced by mothers with celiac disease compared to healthy mothers, which may explain previous controversies regarding the protective effect of breastfeeding on celiac disease. Despite long-term adherence to a gluten-free diet, breast milk from mothers with celiac disease still exhibited a unique immune profile.