title: Electron microscopy and microchemical analysis of cystic fibrosis diploid fibroblasts in vitro.
abstract: Fibroblasts derived from cystic fibrosis homozygotes and heterozygotes were compared to normal fibroblasts topologically, ultrastructurally, and microchemically. Topological examinations, by means of scanning electron microscopy (SEM) revealed no significant differences between the 3 genotypes surveyed. The cells were generally flattened and/or fusiform structures that were more or less devoid of surface details. However, the dividing cells, in all of the populations surveyed, were found to have a more or less spherical configuration involving a highly complicated surface. The surface manifestations included blebs, ridges, and microvilli. Representative samples of the cells in all stages of growth, lag phase, exponential phase, and plateau phase, were surveyed in this study. Ultrastructurally, the fibroblasts of the 3 genotypes were found to have similar cytological detail. Highly infolded nuclei, distinct organelle components, and surface details, also seen in the SEM study, were observed. Numerous bundles of microfilaments were noted within the cytoplasm. Metachromatic granules were observed in cells from all 3 genotypes. Microchemical analysis, by means of energy dispersive X-ray analysis, demonstrated slight but recognizable differences in the elemental composition of the 3 genotypes. Of notable interest were the peak intensities of calcium and sulfur. The CF homozygous cells presented higher values for both of the elements when compared to the values observed in the CF heterozygous and normal cell populations. Although consistent differences could be observed in the CF genotypes when compared to the non-CF cells, no attempt was made to quantitate the concentrations of each of the elements within the cells.
mesh_terms: D000328:Adult; D000818:Animals; D002118:Calcium / Q000032:analysis; D002455:Cell Division; D002460:Cell Line; D002478:Cells, Cultured; D002648:Child; D003550:Cystic Fibrosis / Q000378:metabolism / Q000473:pathology*; D003593:Cytoplasm / Q000648:ultrastructure; D004171:Diploidy; D005260:Female; D005347:Fibroblasts / Q000648:ultrastructure; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007223:Infant; D008297:Male; D013455:Sulfur / Q000032:analysis
chemical_list: D013455:Sulfur; D002118:Calcium