FOR 5775:  Macrophage Niche Network Dynamics - Defining macrophages as choreographers of tissue development and function

• Subject Area: Biology ; Medicine
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 533863915

In multicellular organisms, cells constantly send and receive signals to coordinate body functionality. At the level of tissues or organs, cells orchestrate tissue function locally via signalling through receptors or soluble mediators. Certain cell types are essential for tissue structure and integrity, such as epithelial cells that create barriers and surfaces, endothelial cells that line the blood vasculature, and fibroblasts that synthesize extracellular matrix and collagen. In addition to these structural cell types, macrophages are integral to every organ. Macrophages arise early during embryogenesis and colonize developing organs, forming a 3D network within every tissue. Evolutionary, macrophages are highly conserved innate immune cells present in vertebrates and invertebrates. Despite their omnipresence in all organs during development and steady-state conditions, the cellular and molecular responses of macrophages have been mainly studied in the context of immunity and inflammation. However, a systematic analysis of macrophage core functions beyond their inflammatory or infection-related response is largely lacking. The goal of the interdisciplinary FOR MagNet is to use state-of-the-art research approaches to decipher the role of macrophages within their subtissular niches in various organs. Taken together, our work will make an important contribution to the characterization of macrophage core functions and lead to a better understanding of organ development and function.

• DFG Programme: Research Units

Projects

• Coordination Funds (Applicant Mass, Elvira )
• Data management, analysis and integration (Applicant Hasenauer, Jan )
• Deciphering the interrelation between Kupffer cells and hepatocyte polyploidization integration (Applicants Kiermaier, Eva ;  Mass, Elvira )
• DNA damage in macrophages controls reciprocal interactions with host tissue cells (Applicants Kierdorf, Katrin ;  Paeschke, Katrin )
• Role of macrophage-derived ApoE in the stem cell-ness and differentiation of hematopoietic stem cells (Applicant Mass, Elvira )
• Role of macrophage-derived Apolipoprotein E in the regulation of small intestinal macrophage longevity and function (Project 4 of the FOR5775 MagNet) (Applicant Schlitzer, Andreas )
• Role of the materno-fetal IgG bone marrow macrophage axis for early B cell development (Applicant Nimmerjahn, Falk )
• Understanding the role of macrophage-fibroblast networks in extracellular matrix turnover and recycling. (Applicant Uderhardt, Stefan )
• Unravelling the role of IL-23 secretion by efferocytic macrophages in maintaining and reestablishing intestinal homeostasis (Applicant Bosurgi, Ph.D., Lidia )

• Spokesperson: Professorin Dr. Elvira Mass