Previously, the team of Pr. Véronique Flamand (Institute for Medical Immunology) has described a population of precursors of cDC1 (called pre-cDC1), that is the dominant splenic cDCs population during the first week of life and that displays unique regulatory properties. Indeed, able to produce IL-12p40 and IL-10 depending on the environment, pre-cDC1 are directly involved in the orchestration of neonatal immune responses and in the protection against Listeria monocytogenes infection through the induction of CD8+ T-cell responses.
In this recent work published in Gut, Arnaud Köhler and colleagues show that spontaneous functional maturation of pre-cDC1 in the spleen is dependent on neonatal gut microbiota colonization that happens directly after birth. From a mechanistic point of view, this microbiota-effect relies on the production of TNF by innate myeloid cells that directly targets pre-cDC1 population to kick-start its maturation while reducing its regulatory profile.
Original article: Köhler A, Delbauve S, Smout J, Torres D and Flamand V. “Very early-life exposure to microbiota-induced TNF drives the maturation of neonatal pre-cDC1”. Gut 2020