98th Annual Meeting DOG 2000

P 588

Immunohistochemical demonstration of nerve growth factor receptor P75 in the cornea

N. Wakili, C. Rummelt, L. .M. Holbach, B. Seitz

Introduction: The nerve growth factor (NGF) is used as a new treatment modality for neurotrophic corneal ulcers (1). In earlier studies the possible effect of NGF was based on the demonstration of the high-affinity-receptor (TrkA, 140kD) in the cornea (2). The purpose of this pilot study was to demonstrate the low-affinity-receptor (P75, 75 kD) in normal corneas and corneas with different pathological entities.

Methods: 27 corneal buttons (4x normal corneas, 8x herpetic and 2x scrophulous stromal scars, 4x Fuchs` endothelial dystrophy, 2x keratoconus, 7x repeat keratoplasty) were evaluated. In paraffin sections the NGF-receptor P75 (Anti-Human Nerve Growth Factor Receptor p75, Dako company) was identified immunohistochemically.

Results: P75 was not identified in normal corneas, scrophulous stromal scars, Fuchs` dystrophy, keratoconus and repeat keratoplasty as well as in three herpetic scars without lymphoplasmocellular infiltration. In contrast, p75 was demonstrated in five herpetic scars with lymphoplasmocellular infiltration and in the host cornea of two repeat keratoplasties with larger diameter, in which the reason for the first graft was herpetic keratitis.

Conclusions: In paraffin sections the NGF receptor P75 was demonstrated immmunohistochemically in corneal buttons with herpetic stromal scars. The results of this pilot study indicate that the application of nerve growth factor may also be useful in the therapy of persisting corneal ulcers of herpetic etiology.

(1) Lambiase A et al. Topical treatment with nerve growth factor for corneal neurotrophic ulcers. N Engl J Med 1998; 338:1174-1180
(2) Lambiase A et al. Expression of nerve growth factor receptors on the ocular surface in healthy subjects and during manifestation of inflammatory diseases. Invest Ophthalmol Vis Sci 1998; 39:1272-1275
Department of Ophthalmology, University of Erlangen-N├╝rnberg, Schwabachanlage 6, D-91054 Erlangen