Pathogenic Aspergillus and Fusarium as important causes of blinding corneal infections - the role of neutrophils in fungal killing, tissue damage and cytokine production

Abstract

Filamentous fungi Aspergillus and Fusarium species are major causes of visual impairment and blindness in immune competent individuals. Once conidia penetrate the corneal epithelium and enter the stroma, they undergo germination, and exposure of cell wall components induces a pronounced neutrophil-rich cellular infiltrate. In this review, we discuss Aspergillus and novel Fusarium virulence factors that are required for corneal infection, and describe the multiple functions of neutrophils in limiting hyphal growth in the cornea. This review will also discuss the role of neutrophils as an important source of cytokines in fungal keratitis, and highlight recent studies identifying unique characteristics of neutrophil secretion of IL-1α and IL-1β.