In the past, electron microscopy was used to visualise and characterise mast cells.
Real-Time Imaging of Mast Cell Degranulation in Vitro and In Vivo - \citet*{Horiguchi_2016}
Developed a pH-sensitive system to visualise mast cell degranulation.
  • The green patches co-localise with newly formed CD63-a degranulation marker-indicating that impH enables visualisation of mast cell degranulation in vitro. 
  • Able to show degranulation process in vivo using mast cell deficient mice reconstituted with either wild-type of FcRgamma-deficient BMMC. Inject the ear skin of mice interdermally with TNP-IgE prior to IV injection with TNP-OVA. Green patches only seen in mice reconstituted with wild-type BMMC, illustrating that the impH system utilises the engagement of the allergen bound-IgE receptors prior to degranulation.