Abstract
Abstract: :
Purpose:The purpose of the present study was to characterize the extracellular matrix (ECM) components in an anterior subcapsular cataract (ASC). Focus was put on the distribution of ECM components and deposition of growth factors. We also examined the subcellular localization of Smad3 and Erk-1 in lens cells (LECs) in ASC tissues. Methods:During cataract surgery in 14 patients, we obtained an anterior capsule with an ASC. Each specimen was immunostained with antibodies against collagen types I, IV, V and VI, fibronectin, fibrillin-1, LTBP-1, ß1-LAP, TGFß2, TGFß3, FGF2, or HGFα. Erk-1, the MAP kinase cascade-related molecule, and Smad3, TGFß signaling molecule, were also localized in lens cells. Results:Collagen types I, V, VI, fibronectin, fibrillin-1 and LTBP-1 were all localized to the ECM in ASC tissues. Collagen IV was localized to the ECM and the capsule. LECs and ECM stained for ß1-LAP and TGFß2, but not for TGFß3. FGF2 was localized to the ECM, while HGFα was not detected. LECs with nuclei positive for Erk-1 or Smad3 were also seen. Conclusion:Matrix components, i. e., collagen types, fibronectin, fibrillin-1, as well as growth factors such as TGFß1, TGFß2 and FGF-2 were detected in ASC. These growth factors may modulate the phenotipic alteration and behavior of LECs. TGFß3 and HGFα were not detected there, implicating unrelatedness of such factors in ASC-genesis. The MAP kinase cascade and TGFß signaling are both activated in LECs in ASC.
Keywords: 403 extracellular matrix • 434 immunohistochemistry • 423 growth factors/growth factor receptors