Immuno-histochemical evaluation of conjunctival remodelling in vernal keratoconjunctivitis.
OBJECTIVE
To study the expression of the extracellular matrix (ECM) proteins, tenascin, laminin, and fibronectin in the conjunctiva of patients with active vernal keratoconjunctivitis (VKC).


METHODS
Conjunctival biopsy specimens were obtained from nine patients with active VKC and 6 normal control subjects. The presence and distribution of tenascin, laminin, and fibronectin were assessed microscopically with immunohistochemical techniques and a panel of monoclonal and polyclonal antibodies directed against tenascin, laminin, and fibronectin.


RESULTS
In normal conjunctiva, weak immunoreactivity for tenascin was localized to the walls of blood vessels in the upper substantia propria. Weak immunoreactivity for laminin was located at the epithelial-stromal junction and in the walls of blood vessels. Staining for fibronectin was absent. In VKC specimens, intense immunoreactivity for tenascin was noted in the substantia propria associated with the inflammatory infiltrate and in the perivascular stroma. Intense immunoreactivity for laminin around all stromal vessels and fibrillar immunoreactivity among basal epithelial cells were noted. There was no immunoreactivity for fibronectin.


CONCLUSIONS
Our data indicate increased deposition of tenascin and laminin in the conjunctiva from patients with active VKC. Our findings suggest that tenascin and laminin might play distinct roles in chronic inflammation seen in VKC.
Abu El-Asrar
A M
AM
Department of Ophthalmology College of Medicine King Saud University Riyadh, Saudi Arabia. abuasrar@ksu.edu.sa
Meersschaert
A
A
Al-Kharashi
S A
SA
Missotten
L
L
Geboes
K
K
D000293:Adolescent; D001808:Blood Vessels / Q000378:metabolism; D002648:Child; D003228:Conjunctiva / Q000098:blood supply / Q000378:metabolism*; D003233:Conjunctivitis, Allergic / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005260:Female; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D007797:Laminin / Q000378:metabolism; D008297:Male; D019063:Tenascin / Q000378:metabolism
D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D007797:Laminin; D019063:Tenascin