Bovine immunoglobulin G (bIgG) was previously shown to enhance innate immune responses to toll-like receptor (TLR) stimulation, via induction of trained immunity. In this study, we investigated whether minimally processed dairy streams with high levels of whey proteins as potential infant nutrition ingredients could also induce trained immunity, and to what extent this can be explained by the presence of bIgG. The minimally processed whey ingredients serum protein concentrate (SPC) and whey protein concentrate (WPC) were tested for their ability to induce trained immunity in human peripheral blood monocytes. Both ingredients induced trained immunity as evidenced by an increased production of TNF-α and, to a lesser extent, of IL-6 upon stimulation with TLR ligands. This was comparable to isolated bovine immunoglobulin G (bIgG) that served as positive control. Depletion of bIgG from both whey protein-containing ingredients did not significantly inhibit the induction of trained immunity, suggesting that the streams contain other components in addition to bIgG that are able to induce trained immunity. These results indicate that minimally processed whey ingredients may contribute to protection against infections through enhancing innate immune responsiveness to pathogens.

The objective of the current study was to evaluate the potential of 2′-FL and GOS, individually and combined, in beneficially modulating the microbial composition of infant and toddler (12–18 months) feces using the micro-Matrix bioreactor. In addition, the impacts of GOS and 2′-FL, individually and combined, on the outgrowth of fecal bifidobacteria at (sub)species level was investigated using the baby M-SHIME^® model. For young toddlers, significant increases in the genera Bifidobacterium, Veillonella, and Streptococcus, and decreases in Enterobacteriaceae, Clostridium XIVa, and Roseburia were observed in all supplemented fermentations. In addition, GOS, and combinations of GOS and 2′-FL, increased Collinsella and decreased Salmonella, whereas 2′-FL, and combined GOS and 2′-FL, decreased Dorea. Alpha diversity increased significantly in infants with GOS and/or 2′-FL, as well as the relative abundances of the genera Veillonella and Akkermansia with 2′-FL, and Lactobacillus with GOS. Combinations of GOS and 2′-FL significantly stimulated Veillonella, Lactobacillus, Bifidobacterium, and Streptococcus. In all supplemented fermentations, Proteobacteria decreased, with the most profound decreases accomplished by the combination of GOS and 2′-FL. When zooming in on the different (sub)species of Bifidobacterium, GOS and 2’-FL were shown to be complementary in stimulating breast-fed infant-associated subspecies of Bifidobacterium longum in a dose-dependent manner: GOS stimulated Bifidobacterium longum subsp. longum, whereas 2′-FL supported outgrowth of Bifidobacterium longum subsp. infantis.

We present a miniaturized, flow-through model for infantile in vitro digestions, following up on our previously published in vitro digestive system for adults. Microfluidic 'chaotic' mixers were employed as microreactors to help emulate the biochemical processing going on in the infantile stomach and intestine. Simulated digestive fluids were introduced into these micromixers, and the mixtures were incubated for 60 min after both the gastric phase and the intestinal phase. The pH of the infantile stomach was set at 5.3, which is higher than that of adults. This leads to entirely different patterns of digestion for the milk protein, lactoferrin, used in our study as a model compound. It was found that lactoferrin remained undigested as it passed through the gastric phase and reached the intestinal phase intact, unlike in adult digestions. In the intestinal phase, lactoferrin was rapidly digested. Our miniaturized, infantile, in vitro digestive system requires much less labor and chemicals than standard approaches, and shows great potential for future automation.

Loss of expression of the transcription regulator DC-SCRIPT (Zfp366) is a prominent prognostic event in estrogen receptor-positive breast cancer patients. Studying the inherent link between breast morphogenesis and tumorigenesis, we recently reported that DC-SCRIPT affects normal mammary branching morphogenesis and mammary epithelium homeostasis. Here we investigated the molecular mechanism involved in DC-SCRIPT mediated regulation of FGF2 induced mammary branching morphogenesis in a 3D organoid culture system. Our data show that the delayed mammary organoid branching observed in DC-SCRIPT-/- organoids cannot be compensated for by increasing FGF2 levels. Interestingly, FGFR1, the dominant FGF2 receptor, was expressed at a significantly lower level in basal epithelial cells of DC-SCRIPT deficient organoids relative to wildtype organoids. A potential link between DC-SCRIPT and FGFR1 was further supported by the predicted locations of the DC-SCRIPT DNA binding motif at the Fgfr1 gene. Moreover, ERK1/2 phosphorylation downstream of the FGFR1 pathway was decreased in basal epithelial cells of DC-SCRIPT deficient organoids. Altogether, this study shows a relationship between DC-SCRIPT and FGFR1 related pERK signaling in modulating the branching morphogenesis of mammary organoids in vitro.