Increased plasma levels of nerve growth factor in vernal keratoconjunctivitis and relationship to conjunctival mast cells.
OBJECTIVE
To evaluate the nerve growth factor (NGF) plasma concentration in patients with vernal keratoconjunctivitis and to correlate it with the histopathology and immunopathology of the disease.


METHODS
An immunoenzymatic assay was performed to measure NGF plasma levels in patients with vernal keratoconjunctivitis and in healthy matched controls. A competitive radioimmunoassay was used to detect eosinophil cationic protein (ECP) and total specific immunoglobulin E (IgE) serum levels. Histologic evaluation was performed in tarsal and bulbar conjunctival biopsies.


RESULTS
Plasma levels of NGF were significantly higher (P < 0.001) in patients with vernal keratoconjunctivitis (mean = 8224.47 +/- 7802.53 pg/ml; median = 121 pg/ml) than in controls (mean = 51.68 +/- 5.94 pg/ml; median 42.5 pg/ml). Conjunctival tissue showed a significant increase of mast cells, eosinophils, and lymphocytes in vernal keratoconjunctivitis. A significant correlation was observed between plasma levels of NGF and the number of mast cells in the tarsal conjunctiva (Cc = 0.81; P < 0.005) and bulbar conjunctiva (Cc = 0.77; P < 0.01) of patients with vernal keratoconjunctivitis. No correlation was found between NGF plasma levels and total IgE serum levels in patients with vernal keratoconjunctivitis; NGF plasma levels were inversely related to the number of circulating eosinophils (Cc = -0.61; P < 0.05) and to the increased serum levels of ECP (Cc = -0.71; P < 0.02).


CONCLUSIONS
These data represent the first reported evidence of increased NGF plasma levels in an allergic human disease and suggest a possible relationship between this neurotrophic polypeptide and inflammatory cells in vernal keratoconjunctivitis.
Lambiase
A
A
Department of Ophthalmology, University of Rome Tor Vergata, Italy.
Bonini
S
S
Bonini
S
S
Micera
A
A
Magrini
L
L
Bracci-Laudiero
L
L
Aloe
L
L
D000293:Adolescent; D000328:Adult; D001798:Blood Proteins / Q000032:analysis; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D003228:Conjunctiva / Q000473:pathology*; D003233:Conjunctivitis, Allergic / Q000097:blood* / Q000276:immunology / Q000473:pathology; D047091:Eosinophil Granule Proteins; D004804:Eosinophils / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007073:Immunoglobulin E / Q000032:analysis; D018836:Inflammation Mediators / Q000032:analysis; D008214:Lymphocytes / Q000473:pathology; D008297:Male; D008407:Mast Cells / Q000473:pathology*; D009414:Nerve Growth Factors / Q000097:blood*; D011863:Radioimmunoassay; D012260:Ribonucleases
D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D018836:Inflammation Mediators; D009414:Nerve Growth Factors; D007073:Immunoglobulin E; D012260:Ribonucleases