Table 1.

Examples of purported roles for eosinophils in health and disease.

Eosinophils in Health

Eosinophils in Disease: complications

Contribute growth factors and matrix metalloproteases for tissue development, remodeling and repair Help maintain mucosal surfaces with high levels of epithelial turnover (e.g., intestine, endometrium) Thymic and plasma cell development Anti-helminth defenses (e.g., via release of granule proteins) Anti-viral responses (e.g., via RNAses in released granule proteins) Anti-bacterial responses (e.g., via release of mitochondrial DNA traps) Anti-fungal immunity (e.g., via recognition of fungal glycans) Control of adiposity (e.g., via release of cytokines that infuence other cells to enhance glucose metabolism and levels of “beneficial” beige fat)

Tissue injury and inflammation - endocardial and myocardial - pruritus, urticarial, angioedema erythroderma, bullous disease - wheeze, pneumonia, cough, chronic rhinosinusitis, nasal polyposis - abdominal pain, dysphagia, dysmotility, fibrosis - coagulopathy and thromboembolic consequences - graft-versus-host disease - transplant rejection - vasculitis and other autoimmune features - drug reactions

Abbreviations used: EGID, eosinophilic gastrointestinal disorders; IBD, inflammatory bowel disease