Potential role of the intestinal microbiota of the mother in neonatal immune education

Mucosal dendritic cells are at the heart of decision-making processes that dictate immune reactivity to intestinal microbes. They ensure tolerance to commensal bacteria and a vigorous immune response to pathogens. It has recently been demonstrated that the former involves a limited migration of bacterially loaded dendritic cells from the Peyer's patches to the mesenteric lymph nodes. During lactation, cells from gut-associated lymphoid tissue travel to the breast via the lymphatics and peripheral blood. Here, we show that human peripheral blood mononuclear cells and breast milk cells contain bacteria and their genetic material during lactation. Furthermore, we show an increased bacterial translocation from the mouse gut during pregnancy and lactation and the presence of bacterially loaded dendritic cells in lactating breast tissue. Our observations show bacterial translocation as a unique physiological event, which is increased during pregnancy and lactation. They suggest endogenous transport of intestinally derived bacterial components within dendritic cells destined for the lactating mammary gland. They also suggest neonatal immune imprinting by milk cells containing commensal-associated molecular pattern

Potential role of the intestinal microbiota of the mother in neonatal immune education

Mucosal dendritic cells are at the heart of decision-making processes that dictate immune reactivity to intestinal microbes. They ensure tolerance to commensal bacteria and a vigorous immune response to pathogens. It has recently been demonstrated that the former involves a limited migration of bacterially loaded dendritic cells from the Peyer's patches to the mesenteric lymph nodes. During lactation, cells from gut-associated lymphoid tissue travel to the breast via the lymphatics and peripheral blood. Here, we show that human peripheral blood mononuclear cells and breast milk cells contain bacteria and their genetic material during lactation. Furthermore, we show an increased bacterial translocation from the mouse gut during pregnancy and lactation and the presence of bacterially loaded dendritic cells in lactating breast tissue. Our observations show bacterial translocation as a unique physiological event, which is increased during pregnancy and lactation. They suggest endogenous transport of intestinally derived bacterial components within dendritic cells destined for the lactating mammary gland. They also suggest neonatal immune imprinting by milk cells containing commensal-associated molecular patterns.Facultad de Ciencias Exacta

Potential role of the intestinal microbiota of the mother in neonatal immune education

Mucosal dendritic cells are at the heart of decision-making processes that dictate immune reactivity to intestinal microbes. They ensure tolerance to commensal bacteria and a vigorous immune response to pathogens. It has recently been demonstrated that the former involves a limited migration of bacterially loaded dendritic cells from the Peyer's patches to the mesenteric lymph nodes. During lactation, cells from gut-associated lymphoid tissue travel to the breast via the lymphatics and peripheral blood. Here, we show that human peripheral blood mononuclear cells and breast milk cells contain bacteria and their genetic material during lactation. Furthermore, we show an increased bacterial translocation from the mouse gut during pregnancy and lactation and the presence of bacterially loaded dendritic cells in lactating breast tissue. Our observations show bacterial translocation as a unique physiological event, which is increased during pregnancy and lactation. They suggest endogenous transport of intestinally derived bacterial components within dendritic cells destined for the lactating mammary gland. They also suggest neonatal immune imprinting by milk cells containing commensal-associated molecular patterns.Facultad de Ciencias Exacta

Potential role of the intestinal microbiota of the mother in neonatal immune education

Mucosal dendritic cells are at the heart of decision-making processes that dictate immune reactivity to intestinal microbes. They ensure tolerance to commensal bacteria and a vigorous immune response to pathogens. It has recently been demonstrated that the former involves a limited migration of bacterially loaded dendritic cells from the Peyer's patches to the mesenteric lymph nodes. During lactation, cells from gut-associated lymphoid tissue travel to the breast via the lymphatics and peripheral blood. Here, we show that human peripheral blood mononuclear cells and breast milk cells contain bacteria and their genetic material during lactation. Furthermore, we show an increased bacterial translocation from the mouse gut during pregnancy and lactation and the presence of bacterially loaded dendritic cells in lactating breast tissue. Our observations show bacterial translocation as a unique physiological event, which is increased during pregnancy and lactation. They suggest endogenous transport of intestinally derived bacterial components within dendritic cells destined for the lactating mammary gland. They also suggest neonatal immune imprinting by milk cells containing commensal-associated molecular patterns.Facultad de Ciencias Exacta

Long-term cysteine fortification impacts cysteine/glutathione homeostasis and food intake in ageing rats

International audienceHealthy ageing is associated with higher levels of glutathione. The study aimed to determine whether long-term dietary fortification with cysteine increases cysteine and glutathione pools, thus alleviating age-associated low-grade inflammation and resulting in global physiological benefits. The effect of a 14-week dietary fortification with cysteine was studied in non-inflamed (NI, healthy at baseline) and in spontaneously age-related low-grade inflamed (LGI, prefrail at baseline) 21-month-old rats. Fifty-seven NI rats and 14 LGI rats received cysteine-supplemented diet (4.0 g/kg of free cysteine added to the standard diet containing 2.8 g/kg cysteine). Fifty-six NI rats and 16 LGI rats received a control alanine-supplemented diet. Cysteine fortification in NI rats increased free cysteine (P < 0.0001) and glutathione (P < 0.03) in the liver and the small intestine. In LGI rats, cysteine fortification increased total non-protein cysteine (P < 0.0007) and free cysteine (P < 0.03) in plasma, and free cysteine (P < 0.02) and glutathione (P < 0.01) in liver. Food intake decreased over time in alanine-fed rats (r (2) = 0.73, P = 0.0002), whereas it was constant in cysteine-fed rats (r (2) = 0.02, P = 0.68). Cysteine fortification did not affect inflammatory markers, mortality, body weight loss, or tissue masses. Doubling the dietary intake of cysteine in old rats increased cysteine and glutathione pools in selected tissues. Additionally, it alleviated the age-related decline in food intake. Further validation of these effects in the elderly population suffering from age-related anorexia would suggest a useful therapeutic approach to the problem

Bacterial Imprinting of the Neonatal Immune System: Lessons From Maternal Cells?

OBJECTIVE. We examined the presence of a natural bacterial inoculum in breast milk and its intracellular transport from the maternal intestine to the breast through the circulation. METHODS. Breast milk and peripheral blood were collected aseptically from healthy donors at various times after delivery, and the presence of viable bacteria was determined through plating. Temporal temperature gradient gel electrophoresis was used to examine the bacterial ribosomal DNA content in milk cells, maternal peripheral blood mononuclear cells, and feces and in corresponding infant feces. Blood from nongravid nonlactating women served as control samples. Bacterial translocation to extraintestinal tissues was also evaluated in virgin, pregnant, and lactating mice. RESULTS. Breast milk contained a low total concentration of microbes of <103 colony-forming units per mL. Temporal temperature gradient gel electrophoresis revealed that maternal blood and milk cells contained the genetic material of a greater biodiversity of enteric bacteria. Some bacterial signatures were common to infant feces and to samples of maternal origin. Bacterial translocation from the gut to mesenteric lymph nodes and mammary gland occurred during late pregnancy and lactation in mice. CONCLUSIONS. Bacterial translocation is a unique physiologic event, which is increased during pregnancy and lactation in rodents. Human breast milk cells contain a limited number of viable bacteria but a range of bacterial DNA signatures, as also found in maternal peripheral blood mononuclear cells. Those peripheral blood mononuclear cells showed greater biodiversity than did peripheral blood mononuclear cells from control women. Taken together, our results suggest that intestinally derived bacterial components are transported to the lactating breast within mononuclear cells. We speculate that this programs the neonatal immune system to recognize specific bacterial molecular patterns and to respond appropriately to pathogens and commensal organisms.Fil: Perez, Pablo Fernando. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Doré, Joel. Nestlé Research Centre. Nestec; FranciaFil: Leclerc, Marion. National Institute for Agronomic Research. Unit for Ecology and Physiology of the Digestive Tract; FranciaFil: Levenez, Florence. National Institute for Agronomic Research. Unit for Ecology and Physiology of the Digestive Tract; FranciaFil: Benyacoub, Jalil. Nestlé Research Centre. Nestec; FranciaFil: Serrant, Patrick. Nestlé Research Centre. Nestec; FranciaFil: Segura Roggero, Iris. Nestlé Research Centre. Nestec; FranciaFil: Schiffrin, Eduardo J.. Nestlé Research Centre. Nestec; FranciaFil: Donnet Hughes, Anne. Nestlé Research Centre. Nestec; Franci