99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel.
99MTechnetium-labeled low density lipoprotein (99MTc-labeled LDL) was developed to detect atherosclerosis by external imaging with the gamma scintillation camera (Lees, et al. J. Nucl. Med. 1985. 26: 1056-1062; Lees, et al. Arteriosclerosis. 1988. 8: 461-470). The present study examined high affinit...
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| Format: | Article |
| Language: | English |
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Elsevier
1991-01-01
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| Series: | Journal of Lipid Research |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0022227520422382 |
| _version_ | 1818590508574834688 |
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| author | AM Lees RS Lees |
| author_facet | AM Lees RS Lees |
| author_sort | AM Lees |
| collection | DOAJ |
| description | 99MTechnetium-labeled low density lipoprotein (99MTc-labeled LDL) was developed to detect atherosclerosis by external imaging with the gamma scintillation camera (Lees, et al. J. Nucl. Med. 1985. 26: 1056-1062; Lees, et al. Arteriosclerosis. 1988. 8: 461-470). The present study examined high affinity LDL receptor recognition and intracellular sequestration of 99MTc-labeled LDL by fibroblasts. There were no significant differences between 99MTc-labeled LDL and 125I-labeled LDL in binding parameters or percent inhibition of accumulation, which indicated that 99MTc labeling did not alter receptor recognition of LDL. At 4 degrees C the Kd (+SE) for 99MTc-labeled LDL and 125I-labeled LDL, respectively, was 1.52 +/- 0.24 and 1.45 +/- 0.14 micrograms/ml; Bmax (+/- SE) was 5.45 +/- 0.48 and 4.89 +/- 0.25 ng/well, respectively. Binding was saturated at about 2 micrograms/ml. The complete linearity of 99MTc-labeled LDL accumulation from 0-6 h and the positive slope from 6-24 h indicated that radiolabel that entered cells as 99MTc-labeled LDL was sequestered; pulse-chase experiments, which measured residual cell-associated radioactivity out to 24 h, also showed that radiolabel was trapped. Because radiolabel sequestration was essentially complete, and because 99MTc-labeled LDL was recognized by the LDL receptor equally as well as 125I-labeled LDL, it should be useful not only for imaging atherosclerosis, but also for quantitatively determining sites of utilization and degradation of LDL. |
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| format | Article |
| id | doaj.art-d7d79be3534a45ec992117075e1fab47 |
| institution | Directory Open Access Journal |
| issn | 0022-2275 |
| language | English |
| last_indexed | 2024-12-16T09:57:40Z |
| publishDate | 1991-01-01 |
| publisher | Elsevier |
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| series | Journal of Lipid Research |
| spelling | doaj.art-d7d79be3534a45ec992117075e1fab472022-12-21T22:35:53ZengElsevierJournal of Lipid Research0022-22751991-01-013211899mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel.AM Lees0RS Lees1Arteriosclerosis Center, New England Deaconess Hospital, Boston, MA.Arteriosclerosis Center, New England Deaconess Hospital, Boston, MA.99MTechnetium-labeled low density lipoprotein (99MTc-labeled LDL) was developed to detect atherosclerosis by external imaging with the gamma scintillation camera (Lees, et al. J. Nucl. Med. 1985. 26: 1056-1062; Lees, et al. Arteriosclerosis. 1988. 8: 461-470). The present study examined high affinity LDL receptor recognition and intracellular sequestration of 99MTc-labeled LDL by fibroblasts. There were no significant differences between 99MTc-labeled LDL and 125I-labeled LDL in binding parameters or percent inhibition of accumulation, which indicated that 99MTc labeling did not alter receptor recognition of LDL. At 4 degrees C the Kd (+SE) for 99MTc-labeled LDL and 125I-labeled LDL, respectively, was 1.52 +/- 0.24 and 1.45 +/- 0.14 micrograms/ml; Bmax (+/- SE) was 5.45 +/- 0.48 and 4.89 +/- 0.25 ng/well, respectively. Binding was saturated at about 2 micrograms/ml. The complete linearity of 99MTc-labeled LDL accumulation from 0-6 h and the positive slope from 6-24 h indicated that radiolabel that entered cells as 99MTc-labeled LDL was sequestered; pulse-chase experiments, which measured residual cell-associated radioactivity out to 24 h, also showed that radiolabel was trapped. Because radiolabel sequestration was essentially complete, and because 99MTc-labeled LDL was recognized by the LDL receptor equally as well as 125I-labeled LDL, it should be useful not only for imaging atherosclerosis, but also for quantitatively determining sites of utilization and degradation of LDL.http://www.sciencedirect.com/science/article/pii/S0022227520422382 |
| spellingShingle | AM Lees RS Lees 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. Journal of Lipid Research |
| title | 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. |
| title_full | 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. |
| title_fullStr | 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. |
| title_full_unstemmed | 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. |
| title_short | 99mTechnetium-labeled low density lipoprotein: receptor recognition and intracellular sequestration of radiolabel. |
| title_sort | 99mtechnetium labeled low density lipoprotein receptor recognition and intracellular sequestration of radiolabel |
| url | http://www.sciencedirect.com/science/article/pii/S0022227520422382 |
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