Unraveling the Potential Role of SIGNR1(CD209b) in Shaping Gut Microbiota During the Early Postnatal Life

Abstract

Increasing evidence suggests a significant interconnection between developing several chronic diseases later in adult life and early-life gut microbiota composition. Postnatal is crucial in shaping gut microbiota, maintaining immune balance, and establishing microbe-host interactions. However, the molecular mechanisms that contribute to shaping gut microbiota in early life remain poorly understood. During this crucial phase, various innate immune receptors play an active role in influencing the gut microbiota. The DC-SIGN receptor and its mouse homolog, SIGNR1, act as a sensor, facilitating communication between microorganisms, particularly Gram-negative bacteria, and the host's immune system. This study aimed to investigate the role of the SIGNR1 receptor in shaping the gut microbiota composition during early life in a murine model. The results showed that Firmicutes was the most abundant phylum in SIGNR1 KO mice, while WT mice displayed a higher abundance of Proteobacteria. Functional composition analysis demonstrated that the proportion of Gram-negative bacteria was notably lower in KO mice compared to WT mice. In addition, the absence of SIGNR1 is associated with alterations in immune response and metabolic pathways, highlighting its potential indirect role in modulating the microbiota. Finally, these results suggest that SIGNR1 may influence early-life gut microbiota composition through direct and indirect mechanisms.