Human Lens Epithelial Cells Proliferate in Response to Exogenous EGF and Have EGF and EGF Receptor

Kojima²,

Ouhashi³

1998

Self Cite

It has been assumed that lens epithelial cells (LECs) existing at the capsulotomy edge have been traumatized through anterior capsulotomy in cataract extraction. In this study, the correlation between traumatized LECs remaining at the anterior capsulotomy edge and epidermal growth factor (EGF) found in the aqueous humor, a cell growth factor though to affect cell morphology, was determined. Anterior lens capsules with adhering LECs were obtained following anterior capsulotomy performed during cataract surgery to first confirm the presence of EGF receptors on LECs, which are needed for EGF to be biologically active. Besides, to identify any EGF receptors on traumatized LECs, I next intentionally traumatized the cells by pressing them with a forceps from the anterior capsular side. It has been found that the LECs containing EGF receptors were always those existing at the edge of the anterior capsular opening and LECs containing EGF receptors existed along the pressed region too. The present results indicate that traumatized LECs along the capsulotomy edge have undergone changes to manifest EGF receptors, thus allowing EGF from the aqueous humor to become more active. The physiological effect of EGF upon these LECs may therefore be one of the causative factors of fibrous opacification of the anterior capsulotomy edge after cataract extraction.

Section: Discussionsupporting

confidence: 66%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Cell Biological Analysis with Respect to Cause of Fibrous Opacification of the Anterior Capsule after Cataract Extraction

Kojima²,

Ouhashi³

1998

Self Cite

“…While the effects of ultraviolet rays and various growth factors have been found to alter the physiological activity of LECs [11, 12, 13], the amount of ultraviolet rays reaching us may be increasing because of the environmental pollution disrupting our ozone layer. This may explain why more patients not only develop atopic dermatitis but also cataract.…”

Section: Discussionmentioning

confidence: 99%

Cell-Biological Analysis of Atopic Cataractous Lenses

Kousaka³

1998

Self Cite

The number of people suffering from atopic dermatitis, a recent social problem believed to have arisen from environmental pollution and changes, continues to increase today, and these patients often encounter complications such as cataract and retinal detachment. In this study, I have conducted (1) a comparative study on the rate of cell proliferation between lens epithelial cells (LECs) obtained from 7 atopic cataractous lenses and from 1 normal lens, (2) a comparative study on cell density and alignment between LECs obtained from 5 nonatopic cataractous lenses and from 5 atopic cataractous lenses and (3) transmission electron microscopy of LECs obtained from 3 atopic cataractous lenses. My findings were as follows: (1) except for 1 case disclosing increased proliferative activity of the cells to become multilayered, LECs of atopic cataractous lenses showed diminished proliferative activity; (2) LECs of atopic cataractous lenses had decreased in cell density and revealed irregular cell alignment; (3) transmission electron microscopy of LECs of atopic cataractous lenses demonstrated multilayered cells, increased intercellular spaces, and degeneration and disappearance of some cells. A longer follow-up period and further studies using cells from additional atopic cataractous lenses are necessary before any conclusions can be drawn. However, obtaining human LECs especially of atopic cataract patients is not easy, and I do feel that my present study, although its number of patients may not be large enough, provides significant findings for further studies on the mechanism of atopic cataract formation.

“…Recently, there have been studies reporting the physiological impact of EGF upon the crystalline lens [7][8][9]. The present author, having confirmed the presence of both EGF receptors and EGF on lens epithelial cells (LECs), discussed the physiological impact of EGF on these cells [10]. In this study, the author performed phasecontrast microscopic studies and transmission electron microscopic studies to define the effect of EGF on the morphology of LECs in a culture system.…”

Section: Introductionmentioning

confidence: 89%

Effect of Epidermal Growth Factor upon Morphological Changes of Human Lens Epithelial Cells

1998

Self Cite

Phase-contrast and transmission electron microscopic studies were performed to evaluate the effect of epidermal growth factor (EGF) upon the morphology of lens epithelial cells (LECs) obtained from human cataractous lenses, cultured on human anterior lens capsules, and divided into the following three groups: group 1 receiving no EGF supplement, group 2 supplemented with 1 ng/ml EGF, and group 3 supplemented with 10 ng/ml EGF. Phase-contrast microscopy revealed that the cells in the group supplemented with 1 ng/ml EGF concentration had elogated, and those supplemented with 10 ng/ml EGF disclosed changes indicating fibroblast-like cells. Under transmission electron microscopy, the cells in the group supplemented with 1 ng/ml EGF concentration had become multilayered and a few cells had a ball-and-socket junction structure and nucleolar chromatin condensation, while those supplemented with 10 ng/ml EGF showed changes not only in the cells but also in the anterior lens capsules to present numerous microfibers. This is the first study to confirm the effect of EGF upon LECs cultured on anterior lens capsules, a condition closely resembling the intraocular environment, and these findings are significant.