Research

Macrophage Recognition of Environmental Particles and Crystals

Today our bodies are exposed to environmental particles such as PM2.5, silica, and engineered nanoparticles. When these particles enter the body, many of them are recognized by macrophages and provoke inflammation, which could cause incurable diseases. For instance, silica and asbestos are well known to cause silicosis and mesothelioma, resepepctively. Carbon nanotubes, highly representative products of nanotechnology, may have asbestosis-like pathogenicity. We are interested in understanding how macrophages recognize such inorganic particles. So far, we have identified class B scavenger receptor SR-B1 for silica （Tsugita et al., Cell Rep., 2017） and Tim4 for carbon nanotubes (Omori et al., Cell Rep., 2021).

Trogocytosis Shapes Immune Responses

The term trogocytosis is from the ancient Greek Trogo, meaning “to bite”, which is a process by which a cell acquires plasma membrane fragments from a neighbor cell in a cell-cell contact-dependent manner. We are interested in understanding how trogocytosis shapes immune responses. So far, we have revealed that MHC trogocytosis regulates NK cell and CD4 T cell function (Nakayama, Front. Immunol., 2015; Nakamura et al., PNAS, 2013; Nakayama et al., PNAS, 2011). Trogocytosis is considered to be involved in various immune responses and diseases such as cancer, infection, and autoimmune diseases. However, many things about this new phenomenon still remain unknown.