Hello. My name is Adrian Piliponsky.
I'm an Associate Professor of Pediatrics and Pathology at the University of Washington.
My laboratory is located at the Seattle Children's Research Institute in Seattle.
The overall goal of my research is to understand how mast cells and
basophils regulate the response of our immune system to bacterial infections.
Today, I will provide you with an overview of
mast cell biology and function with an emphasis on mast cell morphology,
the role of mast cells in allergies,
and other inflammatory conditions;
methyl precursors, tissue residency, and phenotypes.
Also, the mechanism by which mast cells get activated and degranulate,
mast cell activating and inhibitory receptors,
and the ability of mast cells that will lead to performing their duties,
to know about synthesis of lipid mediators, cytokines, and chemokines.
Mast cells are present in the phylogenesis from invertebrates to man.
In fact, invertebrates have specialized mast-like cells of mesoderm origin,
mainly devoted to defense mechanisms associated with the gut or the circulation.
Mast cells are long-lived tissue-resident cells with
an important role in many inflammatory settings, including allergic reactions.
They are key players in the inflammatory response as they can
be activated by many different antigens including
allergens, pathogens, and physiological mediators.
They look like round cells in the microscope with
an unilobular nucleus and dense granules,
as you can see in this picture.
They are located at the boundaries between tissues and the external environment;
for example, at mucosal surfaces of the gut and lungs,
in the skin and around blood vessels where they can promote host defense.
Mast cells can be distinguished from other cells in tissue sections by
metachromatic staining with basic aniline dyes such as aniline blue,
as expected here, also, in this picture.