DIFFERENTIAL INTERFERENCE CONTRAST MICROSCOPY COMBINED WITH IMMUNOFLUORESCENCE - A NEW METHOD TO PHENOTYPE EOSINOPHILS IN-SITU

Several surface receptors are expressed on eosinophils in vitro depend ing on the state of cellular activation, but immunohistochemical studi es of eosinophil-related diseases have mostly focused on the number of infiltrating eosinophils as well as extracellular deposits of eosinop hil granule proteins. The present investigation showed that eosinophil s display a characteristic granular appearance in cryo-sections and cy tospins by differential interference contrast (DIC) imaging. This appr oach appeared to be more reliable for identification of these cells in situ than immunohistochemical labelling of eosinophil granule protein s. Moreover, combined with immunofluorescence microscopy DIC imaging f acilitated three-colour immunofluorescence phenotyping of eosinophils.