Medical Professionals: Laboratory Research:

Co-Stimulatory Molecules in Conjunctiva from Patients with Atopic Keratoconjunctivitis

C. Stephen Foster, M.D.

We examined the expression of co-stimulatory molecules CD28 and its ligands B7-1 (CD80) and B7-2 (CD86) in normal and inflamed conjunctiva from patients with atopic keratoconjunctivitis (AKC).

The expression of co-stimulatory molecules was determined by immunohistochemistry on frozen sections of human conjunctiva using monoclonal antibodies directed against CD28, CD80, and CD86 molecules. Conjunctival biopsy specimens were obtained from nine patients with AKC and from healthy individuals undergoing cataract surgery.

AKC conjunctival epithelium showed more macrophages and CD80 positive cells and CD86 expression. In the substantia propria, AKC specimens showed significantly increased numbers of T cells, macrophages, CD28+, CD86+, and CD80+ molecules. Most of the B7-2 (CD86+) cells macrophages, and Langerhans' cells were located subepithelially. CD86 molecules were significantly higher on AKC conjunctival substantia propria compared to normal conjunctiva

We conclude that expression of the co-stimulatory molecule CD86 is upregulated in conjunctiva from patients with active AKC. This increased CD86 expression may contribute to the sustained immune activation in conjunctiva from patients with AKC.