1055-Notch2 Orchestrates Fibroblastic Specialization

The study explores how Notch2 signaling manages the structural organization of lymph nodes by directing the development of specialized fibroblastic reticular cells. Researchers identified a unique circuit where homeostatic mature dendritic cells provide continuous Jagged1 signals to maintain a specific population of Ccl19-high fibroblasts in the central T cell zone. This interaction creates distinct chemical gradients that are essential for the proper compartmentalization of immune cells, specifically clustering CD8+ T cells and supporting the formation of memory T cell precursors. The investigation confirms that this stromal-immune cell circuit is evolutionarily conserved between mice and humans, suggesting a universal mechanism for maintaining specialized immune niches. Disrupting this pathway leads to the loss of central niches and impairs long-term immunity, highlighting the critical role of these specialized fibroblasts in orchestrating effective immune responses.

References:

• Alouche N, Cannelle H, Favre S, et al. Homeostatic mature dendritic cells instruct fibroblast specialization via Notch2 signaling to establish T cell niches[J]. Immunity, 2026.