The cardiotoxicity of eosinophils

Area of Science:

• Cardiology
• Immunology
• Pathology

Background:

• An association between high blood eosinophil counts and endomyocardial disease has been recognized for decades.
• The underlying mechanisms linking eosinophils to heart damage remained poorly understood.
• Previous research suggested eosinophils might cause endomyocardial damage through unknown mechanisms.

Purpose of the Study:

• To elucidate the mechanisms by which eosinophils contribute to endomyocardial disease.
• To investigate the role of eosinophil granule proteins in cardiac cell injury.
• To explore potential diagnostic and therapeutic targets for endomyocardial disease.

Main Methods:

• Clinical correlation of high eosinophil counts with endomyocardial disease.
• Histopathological examination of blood and tissue for degranulated eosinophils.
• In vitro studies using isolated heart cells and purified eosinophil granule proteins.

Main Results:

• High eosinophil counts, regardless of cause, are linked to endomyocardial disease.
• Degranulated eosinophils and elevated serum eosinophil granule proteins are found in affected patients.
• Eosinophil cationic protein directly damages cardiac cell membranes and mitochondrial respiration enzymes.

Conclusions:

• Eosinophils, particularly eosinophil cationic protein, can directly cause cardiac cell damage.
• These findings support the hypothesis that eosinophils play a causal role in endomyocardial disease.
• This research opens avenues for early diagnosis and treatment of endomyocardial disease globally.