Regulação microambiental de células epiteliais límbicas corneais de coelho expandidas sobre membrana amniótica humana desepitelizada: ênfase para a organização supramolecular dos maiores biopolímeros extracelulares

• Ano de defesa: 2015
• Autor(a) principal: Valdetaro, Gisele Pereira [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Coelho; Colageno; Matriz extracelular; Proteoglicanos; Olhos; Proteoglycans
• Link de acesso: http://hdl.handle.net/11449/128171; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/17-09-2015/000848379.pdf

The goal of this study was to evaluate whether procedures on cell culture alter the supraorganization of amniotic and limbal extracellular matrix (ECM). Anisotropic properties of fibrillar collagen and proteoglycans were studied, since they correspond to major extracellular biopolymers. Rabbit limbal explants were cultured on denuded human amniotic membrane (AM) for two, seven, and 15 days. Uncultured AM and limbus were used as controls. Birefringence parameters related to the supraorganization of collagen fibers, and spectral absorption and linear dichroism (LD) related to the supraorganization of proteoglycans were evaluated. All samples were evaluated on microscope equipped with polarized light, monochromatic filters with varying wavelengths, and digital video camera. Birefringence, absorbances and LD were quantified by using image analyses software (Image J®, NIH, USA). Studies on birefringence showed that parallelism degrees of amniotic collagen fibers were of 1.02 for the control group, 1.17 for the two days culture, 1.26 for the seven days culture, and 1.17 for the 15 days culture. In relation to limbal collagen fibers, parallelism degrees were of 1.33, 1.17, 1.25, and 1.44. Birefringence brightness contrasts of amniotic collagen fibers were of 2.0 for the control group, 13.25 for the two days culture, 19.26 for the seven days culture, and 13.23 for the 15 days culture. In relation to limbal collagen fibers, birefringence brightnesses were of 23.01, 13.39, 19.90, and 30.31. Interference colors due to anomalous birefringence dispersion were observed. Procedures on cell culture induced alterations in absorbance values related to proteoglycans from amniotic and limbal ECM. In all samples, except on those cultured for 15 days, the amniotic ECM showed negative DL values. The DL of limbal ECM varied between negative and positive values for all, except on two days culture