Purpose: The purposes of this study were to investigate the immunostaining of the leukocyte adhesion molecules intercellular adhesion molecule (ICAM)-1 and E-selectin in subfoveal choroidal neovascular membranes (CNVMs) surgically excised from patients with age-related macular degeneration (AMD) and to determine whether prior photodynamic therapy (PDT) alters their immunostaining.
Methods: The localization of ICAM-1 and E-selectin in 10 subfoveal CNVMs was determined by immunohistochemistry. Membranes were also immunostained for CD31 to assess vascularity.
Results: Significantly higher numbers of CD31-staining vessels per unit membrane area were found in the peripheral regions of the membranes compared with the central regions (P = 0.05). ICAM-1 immunoreactivity in the CNVMs was found predominantly on RPE cells, but also on small vessels in the periphery. ICAM-1 staining was significantly more intense in the peripheral, more cellular areas of the membranes than in the central, more fibrotic regions (P = 0.04). ICAM-1 staining in the periphery of the CNVMs was greater than that in choroidal vessels and the RPE of the normal control eye. ICAM-1 immunostaining grade in peripheral regions of the CNVMs decreased with the increasing number of PDT treatments (P = 0.05). Some of the CNVMs also stained for E-selectin in RPE cells and small vessels in the periphery.
Conclusions: In subfoveal CNVMs from patients with AMD, there is increased immunostaining for leukocyte adhesion molecules, particularly in the peripheral, more cellular regions where angiogenesis may be ongoing. Increasing numbers of PDT treatments may be associated with decreased ICAM-1 immunostaining in the proliferating edges of the CNVMs.