Label-free live cell imaging of antigen mediated mast cell degranulation in collaboration with the Max-Planck-Institute

In this video you can observe antigen mediated mast cell degranulation.

Mast cells reside in connective and mucosal tissues near host-environment barriers throughout the body as a part of the immune system. They serve as immunologic sentinels and are major contributors in innate as well as adaptive immune responses. As such, they participate in the recruitment of neutrophils and other immune cells, the priming of T-cell responses, detoxification of venoms, defense against parasitic infections as well as angiogenesis and vascular homeostasis. However, they are most commonly known for their cardinal role in pathological processes related to allergic reactions such as anaphylaxis.

Mast cells contain a large number of cytosolic granules embedding inflammatory mediators like heparin and histamine along with a mixture of chondroitin sulphate and various proteases.

Upon activation, within seconds, mast cells start to release these granules into the microenvironment of their resident tissue. Histamine secretion causes the blood vessels to dilate allowing the recruitment of white blood cells, but it also triggers itching, a typical sign of allergic reaction.

With the 3D Cell Explorer this process can be observed in vitro with unprecedented spatial and temporal resolution. As you can observe, this process involves membrane ruffling and reorganization, the fusion of granule membranes into larger intracellular vesicles, the movement of granules to the sites of exocytosis and finally the release of granules into the surrounding medium.

Thanks to Manuel Stecher and Tim Lämmermann of the Max Planck Institute of Immunobiology and Epigenetics (MPI-IE) for this video.