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V B Bystrevskaya

Publications and source records attributed to V B Bystrevskaya.

7 recordsLinked to original sources

Centrosome-directed translocation of Weibel-Palade bodies is rapidly induced by thrombin, calyculin A, or cytochalasin B in human aortic endothelial cells.

To examine the possible role of the cytoskeleton in exocytosis of Weibel-Palade bodies (WPBs), we used double immunofluorescence and electron microscopy to study the spatial relationships between WPBs and main cytoskeletal elements in endothelial cells treated with secretagogue, such as thrombin, or cytoskeleton-damaging agents. Unexpectedly, we have found that WPBs undergo rapid translocation towards the centrosome both in cells treated with thrombin and in those treated with cytochalasin B or calyculin A. Typically, 3 or 5 min after agent addition compact cluster of WPBs became visible near the microtubule-organizing center (MTOC) in most endothelial cells in which a fivefold increase in WPBs localized in close proximity to the mother centriole had been detected. In both thrombin- and cytochalasin-treated cells that exhibit a noticeable depletion in WPBs compared to control cells, WPBs located at the cell periphery were found to colocalize with vimentin intermediate filaments, but not with microtubules. In contrast, there was precise colocalization observed between WPBs and microtubules in calyculin-treated cells in which all WPBs undergo centrosome-directed translocation within 15 min after the agent addition. When vimentin filaments were induced to collapse to a perinuclear location by the microtubule-disrupting agent demecolcine, WPBs also translocated to the perinuclear region, where numerous WPBs were found to be localized within the bundles of intermediate-sized filaments. The data provide the first direct evidence that secretory granules utilize microtubule-based transport system to move in retrograde direction, i.e., away from the plasma membrane, towards the centrosome. We suggest that anterograde movement of WPBs is primarily dependent on their interaction with vimentin intermediate filaments.

Adult↗

Cytomegalovirus genome and the immediate-early antigen in cells of different layers of human aorta.

A number of data suggest that reactivation of cytomegalovirus (CMV) latent in arterial wall cells may contribute to atherogenesis; however, there is no direct evidence available. To address this issue, we have examined, using in situ hybridization or immunohistochemical staining, the frequency of occurrence of cells containing viral genome and of those expressing the IE 70 viral antigen in the endothelial layer and in deeper layers of human aortas with or without visible atherosclerotic lesions. Using endothelial cell cultures or tissue endothelial preparations, we found CMV-hybridizing endothelial cells in 6 of 8 grossly normal aortas and in 16 of 18 lesioned aortas. Antigen-positive endothelial cells were detected in 1 of 5 grossly normal vessels and in 6 of 7 lesioned vessels. Infected endothelial cells were abundant in areas adjacent to orifices of intercostal arteries of grossly normal aortas and in fatty spots of lesioned aortas, but no infected endothelial cells were observed in most plaques examined. In paraffin sections of grossly normal vessels, we detected CMV genome in cells adjacent to lumen and in cells randomly scattered through subendothelial intima and the media; however, no immunoreactive viral protein was found in the same tissue samples. In sections of lesioned vessels, clusters of CMV-hybridizing cells were found in the media in addition to infected cells randomly scattered through the intima and the media. In these samples of lesioned vessels, viral antigen was detected in cells adjacent to lumen and in cells clustered at the intima/media border. We found antigen-positive cells in grossly normal areas of lesioned aortas and in fatty lesions, but not in plaques of the same vessels. The data suggest that accumulation of the immediate-early CMV antigen in cells of endothelial layer and development of antigen-positive cell clusters in deeper layers of vascular wall accompany early atherogenic events in human aorta.

Adolescent↗

Centrosome injury in cells infected with human cytomegalovirus.

The organization of the mitotic apparatus was studied in human embryo lung fibroblasts (HEL) and Vero cells at 4 days postinfection with human cytomegalovirus (HCMV) strain AD 169. The bipolar spindle was detected by immunofluorescence in p72-positive mitotic cells exhibiting a regular or C-metaphase-like chromosome configuration. Electron-microscopic study of C-metaphase-like cells revealed alteration of the centrosome structure which is characterized by the following features: (1) breakdown of the diplosome, (2) separation of the fibrillar material from centrioles, and (3) disruption of the centriolar cylinder. The spindle pole in the aberrant mitotic cells consisted of one or several foci of microtubules converging on the fibrillar aggregates. There are not any signs of the nuclear envelope reconstruction found in mitotic cells with highly condensed scattered chromosomes. Unlike in HEL cells, viral particles were not detected in Vero cells. A question arises as to whether centrosome injury is an integral part of the events leading to cell death unrelated to the reproduction of HCMV.

Anaphase↗

An ultrastructural study of centriolar complexes in adult and embryonic human aortic endothelial cells.

Ultrastructural organization of centriolar complexes in 90 adult human aortic endothelial cells from uninvolved areas, fibrous and atheromatous plaques and 30 endothelial cells from human embryonic aorta were studied using serial sections. Primary cilia protruding from the abluminal cell surface were found on 28 of 30 endothelial cells from atheromatous plaques. Only five of 30 cells from either fibrous plaques or uninvolved areas developed primary cilia protruding to the lumen. Impaired primary cilia entirely immersed into the cytoplasm were found in embryonic endothelial cells. It was speculated that both the modes of formation and the functions of endothelial cilia in embryonic and adult aortas are different.

Aorta↗

Primary culture of endothelial cells from atherosclerotic human aorta. Part 1. Identification, morphological and ultrastructural characteristics of two endothelial cell subpopulations.

Endothelial cells (EC) were harvested by 0.1% collagenase treatment for adult human thoracic aortas obtained 1-3 h after sudden death. At least 35-70% of EC were removed from the intimal surface of aorta, 90-95% of them being viable. Plating efficiency was 70-80%. Monolayer formation was achieved at a seeding density of 5-8 X 10(2) cells/mm2. The cells were identified as endothelium by the presence of Factor VIII antigen, Weigel-Palade bodies and typically endothelial morphology at confluence. Unlike endothelial cultures derived from human umbilical veins and infant aortas, primary cultures obtained from human adult aortas contain multinuclear EC with Factor VIII antigen and Weibel-Palade bodies. The number of multinuclear EC in cultures isolated from aortas affected by atherosclerosis was 2-fold higher (P less than 0.05) than in cultures obtained from grossly normal aortas taken from donors of the same age. EC with numerous lipid inclusions revealed by oil-red-O staining were present in all the EC primary cultures derived from aortas affected by atherosclerosis. No oil-red-O-positive cells were detected among the EC cultured from infant aorta, aorta of young donors, and umbilical vein. An electron microscopic examination of EC from atherosclerotic aorta in culture and in situ failed to reveal any ultrastructural peculiarities distinguishing multinuclear EC from the mononuclear EC.

Adult↗

Centriole modification in human aortic endothelial cells.

The structure of centrioles in endothelial cells of embryonic (22-24 weeks old) and definitive (2, 14-17, and 30-40 years) human aorta in situ and also in aortic endothelial cells dividing in organ and cell cultures (donor age 30-40 years) was studied. It was found that in the endothelial cells from definitive aorta the lengths of mother centrioles vary from 0.5 to 2 microns, whereas the length of daughter centrioles remains constant (0.4-0.5 microns). The distal part of the cylinder of long mother centrioles consists of microtubule doublets. In aorta of donors 30-40 years old in multinucleated cells and in one of 30 single-nucleated cells analyzed, C-shaped long centrioles were seen. These centrioles exhibit a doublet organization along all their length. Mitotic cells in organ and cell culture had a nonequal structure of spindle poles: at one pole, the long mother centriole was seen, while at the other a mother centriole of standard size was found. In such cells of organ culture long centrioles make contact with the remnant of primary cilia until the end of anaphase. In cell culture mitotic cells are also observed containing C-shaped centrioles. In these cells the number of mother centrioles is odd and their number is not equal to the number of daughter centrioles. The possible mechanism for transformation of endothelial centrioles and its role in the control of cell-cycle progression are discussed.

Adolescent↗