Continued ultrastructural and functional studies of fiber cell junctions in normal aging and cataractous lenses are proposed. High resolution LM studies on vibratome sections of fresh lenses will be used to complement EM studies on similar preparations, permitting an excellent degree of correlation between the two. The principal aim is to use comparison of normal and cataractous lenses to define the causes of light scatter. The central hypothesis is that the breakdown of plasma membranes is followed by a leakage of cytoplasmic contents creating local refractive index variations at cell interfaces. Also evaluated will be a) cell viability in the nuclear core using confocal microcopy b) the preservation of membranes in the oldest cells by TEM, c) Fourier analysis of cytoplasmic texture d) the definition of protein-like deposits in the extracellular space. Also characterized will be light scatter centers in nuclei from human diabetic lenses, and spontaneously occurring diabetic canine lenses.

National Institute of Health (NIH)
National Eye Institute (NEI)
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Visual Sciences A Study Section (VISA)
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University of North Carolina Chapel Hill
Anatomy/Cell Biology
Schools of Medicine
Chapel Hill
United States
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Bassnett, Steven; Costello, M Joseph (2017) The cause and consequence of fiber cell compaction in the vertebrate lens. Exp Eye Res 156:50-57
Costello, M Joseph; Brennan, Lisa A; Mohamed, Ashik et al. (2016) Identification and Ultrastructural Characterization of a Novel Nuclear Degradation Complex in Differentiating Lens Fiber Cells. PLoS One 11:e0160785
Mohamed, Ashik; Gilliland, Kurt O; Metlapally, Sangeetha et al. (2013) Simple fixation and storage protocol for preserving the internal structure of intact human donor lenses and extracted human nuclear cataract specimens. Mol Vis 19:2352-9
Costello, M Joseph; Mohamed, Ashik; Gilliland, Kurt O et al. (2013) Ultrastructural analysis of the human lens fiber cell remodeling zone and the initiation of cellular compaction. Exp Eye Res 116:411-8
Costello, M Joseph; Brennan, Lisa A; Basu, Subharsee et al. (2013) Autophagy and mitophagy participate in ocular lens organelle degradation. Exp Eye Res 116:141-50
Costello, M Joseph; Burette, Alain; Weber, Mariko et al. (2012) Electron tomography of fiber cell cytoplasm and dense cores of multilamellar bodies from human age-related nuclear cataracts. Exp Eye Res 101:72-81
Costello, M Joseph; Johnsen, Sonke; Metlapally, Sangeetha et al. (2010) Multilamellar spherical particles as potential sources of excessive light scattering in human age-related nuclear cataracts. Exp Eye Res 91:881-9
Costello, M J; Johnsen, Sonke; Metlapally, Sangeetha et al. (2008) Ultrastructural analysis of damage to nuclear fiber cell membranes in advanced age-related cataracts from India. Exp Eye Res 87:147-58
Metlapally, S; Costello, M J; Gilliland, K O et al. (2008) Analysis of nuclear fiber cell cytoplasmic texture in advanced cataractous lenses from Indian subjects using Debye-Bueche theory. Exp Eye Res 86:434-44
Costello, M Joseph (2006) Cryo-electron microscopy of biological samples. Ultrastruct Pathol 30:361-71