We used electron microscopy and immunohistochemistry to study the macular regions of nine enucleated elderly human eyes and to document the various abnormalities present in the so-called basal linear deposit. These changes include bush-like strands of electron-dense material, which project from the basement membrane of the retinal pigment epithelium, deposition of wide-banded collagen, vesiculoid elements, membrane-bound structures and occasional melanin granules. Fibronectin was also identified in the basal linear deposit and in Bruch's membrane, but mucopolysaccharides could not be demonstrated. The presence of electron-empty space suggests a disturbance in water permeability. Our studies also showed neovascularisation beneath the retinal pigment epithelium in locations where the basal linear deposit was abundant, as well as erosion of Bruch's membrane by macrophages and endothelial cell processes. Our findings suggest that the basal linear deposit is an important precursor of neovascularisation. Possible pathogenetic mechanisms are discussed.

We investigated the immunohistochemical distribution of 3 components of the renin-angiotensin system (RAS), angiotensin-converting enzyme (ACE), angiotensin II (AngII) and AT1 receptor (AT1), in the human eye. ACE and AngII were localized to nonpigmented epithelial cells of the ciliary body, to endothelial and epithelial cells of the cornea, to epithelial cells of the conjunctiva and to trabecular meshwork cells in the anterior part of the eye. In the posterior part of the eye, ACE and AngII were localized to ganglion cells, some cells in the inner nuclear layer, photoreceptor cells and to endothelial cells of the retinal and choroidal vessels. The overall intensity of AT1 immunoreactivity was weak in all ocular tissues, but the main localization was in ganglion cells. As a preliminary investigation, we were able to include 2 Alzheimer’s disease (AD) cases. In AD, no differences from controls were found in the cellular distribution and staining intensity of all 3 antigens. The manifold localization sites of the observed antigens point to rather generalized functions of the RAS in human ocular tissues, such as regulatory effects on neuronal cells, vessels and vitreous humor homeostasis.

JSM6427 is a promising treatment for PVR, with data suggesting that inhibition of alpha5beta1-fibronectin interactions addresses multiple pathways involving retinal pigment epithelial, glial, and inflammatory cells.

Anmerkung der Autoren Einige der ansonsten recht oft zitierten Literaturstellen aus China waren leider nicht nachverfolgbar. Wir haben deswegen hier nur Arbeiten zitiert, wo zumindest ein englischsprachiges Abstract zur Verfügung stand. Nicht alle Arbeiten sind "peer-reviewed". PAS, Elastika-van-Gieson und Masson-Trichrom gefärbt. Separat wurde auch jeweils ein Querschnitt des N. opticus untersucht. Die histologischen Schnitte wurden von 3 Ophthalmopathologen (KUL, MCH-C, PM) unabhängig voneinander ausgewertet.