Extracellular matrix ligands promote RPE attachment to inner Bruch's membrane.
OBJECTIVE
To determine if resurfacing layers of human Bruch's membrane with extracellular matrix ligands increases adult human retinal pigment epithelium (RPE) attachment.


METHODS
We removed successive layers of Bruch's membrane sequentially by mechanical or enzymatic means to expose the RPE basal lamina, inner collagen layer, and elastin layer. Each layer was coated with extracellular matrix proteins (4 microg/cm(2) laminin, 4 microg/cm(2) vitronectin, 20 microg/cm(2) fibronectin, 20 microg/cm(2) collagen IV) for 2 hrs at 37 degrees C. First passage adult human RPE (15000 cells/6 mm explant) were plated onto coated or uncoated Bruch's membrane layers and RPE attachment was measured 18 hrs later.


RESULTS
The reattachment rate to basal lamina derived from younger (age < 50) donors was higher than older (age >/= 70) donors (56.2 +/- 4.8% versus 46.7 +/- 0.7% respectively; p < 0.05). Coating with laminin or collagen IV increased RPE attachment to older but not younger basal lamina. The reattachment rate to inner collagen derived from younger donors was higher than older donors (51.3 +/- 2.7% versus 37.4 +/- 1.7% respectively, p < 0.05). Coating with laminin, fibronectin or collagen IV increased RPE attachment to older but not younger inner collagen layer. Adding extracellular matrix ligands did not increase RPE attachment to elastin.


CONCLUSIONS
RPE attachment is increased by adding ligands to the basal lamina or inner collagen layer but not to the elastin layer. This may be important if the elastin layer is exposed in AMD patients after submacular surgery.
Del Priore
Lucian V
LV
Department of Ophthalmology, Columbia University, New York, NY 10032, USA. ldelpriore@yahoo.com
Geng
Lee
L
Tezel
Tongalp H
TH
Kaplan
Henry J
HJ
D000328:Adult; D000368:Aged; D016570:Bruch Membrane / Q000187:drug effects / Q000378:metabolism*; D002448:Cell Adhesion / Q000502:physiology; D002478:Cells, Cultured; D024141:Collagen Type IV / Q000494:pharmacology; D005109:Extracellular Matrix / Q000187:drug effects*; D016326:Extracellular Matrix Proteins / Q000494:pharmacology*; D005353:Fibronectins / Q000494:pharmacology; D006801:Humans; D007797:Laminin / Q000494:pharmacology; D008024:Ligands; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000502:physiology*; D019096:Vitronectin / Q000494:pharmacology
D024141:Collagen Type IV; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D007797:Laminin; D008024:Ligands; D019096:Vitronectin