Neutrophil and eosinophil participation in atopic and vernal keratoconjunctivitis

A retrospective study was conducted at three centers to examine the participation of neutrophils and eosinophils in the inflammatory processes associated with atopic keratoconjunctivitis (AKC) and vernal keratoconjunctivitis (VKC).

Conjunctival specimens were obtained from four patients with AKC, six with VKC, and five normal subjects. Indirect immunofluorescent staining was used to localize neutrophil elastase (NE) and eosinophil granule major basic protein (MBP) in serial sections of all specimens.

Specimens from both AKC and VKC patients revealed extracellular deposition of NE and MBP. Control specimens showed no or minimal extracellular NE, and no MBP. Statistical analysis demonstrated significantly greater extracellular MBP deposition in AKC specimens compared to controls (p = 0.009), and VKC specimens showed significantly greater staining for both extracellular MBP (p = 0.005) and NE (p = 0.006).

These results suggest that neutrophils, in addition to eosinophils, play an active role in the pathogenesis of AKC and VKC as evidenced by the extracellular deposition of their specific granule proteins.