Blood identified and quantified in formalin fixed paraffin embedded lung sections using eosin fluorescence

Area of Science:

• Histology
• Fluorescence Microscopy
• Biomedical Imaging

Background:

• Eosin Y is a widely used histological stain for colorimetric imaging.
• Beyond its colorimetric use, Eosin Y possesses inherent fluorescence properties.
• Its potential for quantitative analysis in fluorescence microscopy remains underexplored.

Purpose of the Study:

• To investigate the fluorescence characteristics of Eosin Y in formalin-fixed paraffin-embedded (FFPE) tissue sections.
• To develop a method for quantifying specific tissue structures using Eosin Y fluorescence.
• To explore the utility of Eosin Y fluorescence in histopathological analysis.

Main Methods:

• Prepared FFPE hamster tissue sections stained with haematoxylin and Eosin Y.
• Acquired fluorescence emission spectra of Eosin Y using confocal laser scanning microscopy under blue light.
• Utilized an image analysis algorithm for quantification of red blood cells.

Main Results:

• Distinct fluorescence spectral differences were observed between red blood cells/congealed blood and other tissue components.
• These spectral distinctions enabled clear visualization in fluorescence and multi-photon microscopy.
• An image analysis algorithm successfully quantified red blood cells based on Eosin Y fluorescence.

Conclusions:

• Eosin Y can be effectively utilized as a fluorochrome for quantitative analysis in FFPE tissues.
• The distinct fluorescence of Eosin Y allows for the differentiation and quantification of specific structures like red blood cells.
• This approach has potential applications in histopathology for analyzing conditions involving blood, such as clotting disorders or hemorrhage.