Characterization of specialized innate immune cells in the omentum.

The great omentum is an intraperitoneal organ and plays an important role in protecting the environment of the peritoneal cavity. Several specialized innate immune cells including B1 cells and resident macrophages are found in the omentum, which may be attributed to the unique niche and its special stromal cells. However, it is not clear how these omental innate immune cells contribute to the peritoneal immunity. This review attempts to summarize the latest research on the omental innate immunity and discuss its involvement in the immune response of the peritoneal cavity.