Immunity: Fat cells - sentinel of the immune system

February 6, 2021 // -- Fat cells have the ability to resist pathogens and regulate the inflammatory response of the immune system.
cells and neutral granulocytes are white blood cells and are essential for the body's immune defenses.
recent study, immunologist Professor Anne Dudeck and bioengineer Jan Dudeck identified key mechanisms for communication between fat cells and neophilic granulocytes.
new findings may help develop innovative targeted treatment strategies to reduce allergic and inflammatory reactions.
findings have been published in the journal Immunity.
(Photo source: www.pixabay.com) neutral granulocytes are the body's first line of defense against infection.
, fat cells are tissues that host cells and act as sentinels, responding to pathogen or tissue damage by attracting more immune cells.
have long been considered "harmful" because they can cause allergic reactions.
released by fat cells can cause symptoms associated with allergies: hay fever, itching, urticaria and even shortness of breath.
but it's just one side of the coin.
, on the other hand, fat cells are essential for rapid immune response to pathogens, as fat cells coordinate the arrival of neutral granulocytes at the site of inflammation or infection.
first author Jan Dudeck and others analyzed how fat cells affect the collection of neophils.
past few years, scientists have determined that fat cells are involved in the process, but until now the exact molecular mechanisms have remained elusive.
that TNF, the source of fat cells, activates endothial cells in blood vessels.
neophils circulating in the blood are activated directly to migrate to inflamed tissue.
, however, how to transfer TNF, where tissue resides in fat cells, to neitrote granulocytes and circulate them within blood vessels? Scientists at the University of Magdeburg used high-resolution dual photon microscopy to show that fat cells allowed fat cells to position themselves directly around blood vessels like guardians, and even insert protrusions into the inner cavity of blood vessels.
in an emergency, particles containing TNF are released directly from these protrusions.
, TNF is immediately present where neophilic granulocytes can be "seen."
TNF activates the surface protein on the neutral granulocytes, so the cells become more sticky, attaching themselves to the walls of the blood vessels and then migrating them to surrounding tissues.
() Source: Mast cells: Sentinels and high-speed messengers of the original source of the immune defense: Jan Dudeck et al, Directional mast cell degranulation of the tumor necrosis into the blood vessels primes neutrophil extravasation, Immunity (2021). DOI: 10.1016/j.immuni.2020.12.017