Heterogeneity, Origins, and Role of Omental Macrophages in Health and Early Tumor Seeding

The host immune system is essential to maintaining tissue homeostasis and clearing pathogens. Tissue-resident macrophages (TRM) are innate immune cells that first appear at primitive hematopoiesis to facilitate fetal organ growth. After birth and depending on environmental cues, monocytes may replace a subset of embryonic-derived macrophages to differentiate into monocyte-derived macrophages. In the past several decades, researchers have begun to understand the details in which TRM regulate other cell populations through precise communication with non-immune cells such as stromal cells and endothelial cells. TRM are involved in identifying foreign substances in the host to initiate acute inflammation, however prolonged signaling can lead to pathogenic conditions relating to cancer and neurodegenerative diseases. Pharmaceutical drugs are being developed to target TRM, however studies are needed to understand the role of each macrophage population in inflammatory conditions. Here we examine omental resident macrophages (ORM) in early tumor seeding conditions. We found genetic ablation serous macrophages led to increased tumor growth in the peritoneal fluid and omentum. Selective ablation of macrophages and stromal cells reveal tumor suppressive CX3CR1+ ORM rely on Ccl19+ fibroblastic reticular cells to migrate to each tumor to restrict its growth. Additionally, we observed CCL19+ fibroblast like cells in the meninges and the cornea layer of the eye. As the central nervous system (CNS) requires precise control of inflammation, we examined CNS-associated macrophages (CAMs) in relation to gut-induced inflammation and various eye injury models to find CAMs provide site-specific responses.

Author dc:creator

• Joseph Raul Dominguez (24400295)

• Health Sciences
• Immunology

Statement dc:rights

• In Copyright
• Open Access after 2028-05-01

DOI dc:identifier

https://doi.org/10.25417/uic.32995355.v1

OAI identifier oai:identifier

oai:figshare.com:article/32995355