Effects of Maternal Immune Factors and Gut Microbiota on Neonatal Peyer’s Patch Development: A Research Protocol

The neonatal immune system is constantly surrounded by new antigens and must learn to balance defense against threats with tolerance for the gut microbiome. Since improper neonatal immune development is associated with conditions like asthma, allergies, and chronic bowel inflammation later in life, understanding factors that influence immune development is crucial to preventing these diseases. Intestinal immunity is managed by the Peyer’s patches of the small intestine, where microfold cells (M cells) sample antigens from the intestinal lumen to stimulate B cells to produce secretory immunoglobulin A (sIgA), which protects the body from potential pathogens. Neonatal Peyer’s patch development is encouraged by maternal immune factors in breast milk and the presence of bacterial genera Bifidobacterium, Lactobacillus, and Staphylococcus in the gut microbiome, but these interactions have not been thoroughly researched. Therefore, we propose an in vitro study to determine the effects of breast milk and each genus of bacteria on neonatal Peyer’s patch development. Microfluidic devices will permit interactions between Peyer’s patches, M cells, and cultures of Bifidobacterium infantis, Lactobacillus salivarius, or Staphylococcus epidermidis in the presence of breast milk or a control formula. Peyer’s patch development will be measured by increased sIgA production and M cell maturation markers, which will be compared between experimental groups. It is predicted that samples involving breast milk will have the greatest immune development, likely due to the presence of maternal immune factors which encourage sIgA production. Additionally, it is predicted that Bifidobacteria will induce more development than Lactobacilli and Staphylococci since it is the predominant bacterial genus in the neonatal gut microbiome. This study aims to present evidence that breastfeeding and probiotics can improve neonatal immune development to help prevent inflammatory disease later in life.