Intravital imaging allows real-time characterization of tissue resident eosinophils

Area of Science:

• Immunology
• Cell Biology
• Microscopy

Background:

• Eosinophils are crucial immune cells, but in vivo observation tools are limited.
• Understanding tissue-resident eosinophil roles requires dynamic imaging capabilities.

Purpose of the Study:

• To develop and utilize novel reporter mouse models for real-time in vivo visualization of eosinophils.
• To investigate the dynamic behavior and tissue distribution of eosinophils in healthy and diseased states.

Main Methods:

• Generation of eosinophil-specific CRE (eoCRE) reporter mice expressing GFP and tdTomato.
• Intravital microscopy to observe eosinophil behavior in the GI tract, mesentery, liver, lymph node, skin, and lung.
• Analysis of eosinophil dynamics in a mouse model of allergic airway disease (ovalbumin challenge).

Main Results:

• Successfully visualized and quantified eosinophil behaviors including patrolling, crawling, and clustering in vivo.
• Detailed the tissue distribution and real-time interactions of eosinophils with other leukocytes.
• Observed eosinophil dynamics in both healthy tissues and following allergic challenge in the lung.

Conclusions:

• Novel eosinophil reporter mice provide unprecedented real-time insights into eosinophil function in vivo.
• These tools facilitate the study of eosinophil roles in health and disease, particularly in allergic conditions.
• Opens new avenues for investigating immune cell dynamics and interactions in living organisms.