Psoriasis as a model for T-cell-mediated disease: immunobiologic and clinical effects of treatment with multiple doses of efalizumab, an anti-CD11a antibody.

Background: Leukocyte function-associated antigen 1 (LFA-1), consisting of CD11a and CD18 subunits, plays an important role in T-cell activation and leukocyte extravasation.

Objective: To test whether blocking CD11a decreases immunobiologic and clinical activity in psoriatic plaques.

Design: Open-label, multicenter, dose escalation study.