advertisement
Abstract #13524 Published in IGR 8-1
Biochemical and morphological analysis of basement membrane component expression in corneoscleral and cribriform human trabecular meshwork cells
Fuchshofer R; Welge-Lussen U; Lutjen-Drecoll E; Birke MInvestigative Ophthalmology and Visual Science 2006; 47: 794-801
PURPOSE: To determine whether cells of the cribriform trabecular meshwork (TM) express basement membrane (BM) components similar to corneoscleral TM cells and to determine whether cribriform cells are connected to the elastic tendon net of the TM. METHODS: TM cells of the corneoscleral and the cribriform regions were cultured from 10 eyes of 10 donors, aged 20 to 87 years. Cell types were classified by alpha-smooth muscle actin (smA), desmin, and αB-crystallin staining. Expression of collagen type IV (ColIV) chains α1 to 6; collagen type VIII (ColVIII) α1; laminin subunits α1 to 5, β1 to 3, and γ1 to 3; and nidogen 1 and 2 was tested in both cell types by semiquantitative RT-PCR (sqPCR). Expression of ColIVα2, ColVIIIα1, laminin β2, and nidogen 1 was quantified by Northern blot analysis. The response to transforming growth factor (TGF)-β2 treatment was investigated. Serial tangential and sagittal TM sections of 16 eyes from 10 donors (aged 12-90 years) were used for electron- and immunoelectron microscopy. RESULTS: Both TM cell types expressed ColIV chains α1, α2, α4, α5, and α6; ColVIII α1; laminin subunits α3, α4, β1, β2, β3, γ1, and γ2; and nidogen 1, as determined by Northern blot analysis and sqPCR. ColIV α3; laminin subunits α1, α2, and γ3; and nidogen 2 were not detectable by PCR. Responses to TGF-β2 treatment did not differ between cell types. In vivo, all cribriform cells were in contact with ColIV containing BM material and were found to connect to the cribriform elastic network. CONCLUSIONS: Cribriform and corneoscleral TM cells show no differences in expression of BM components and response to TGF-β2. The direct connection of cribriform cells to the elastic tendon network suggests that they are under mechanical tension. This could explain previous findings of αB-crystallin expression in the cribriform region.
Dr. R. Fuchshofer, Department of Human Anatomy, University Regensburg, Regensburg, Germany
Classification:
2.5 Meshwork (Part of: 2 Anatomical structures in glaucoma)
3.5 Molecular biology incl. SiRNA (Part of: 3 Laboratory methods)
3.6 Cellular biology (Part of: 3 Laboratory methods)
