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Binding, internalization, and degradation of antiproliferative heparan sulfate by human embryonic lung fibroblasts

Arroyo-Yanguas, Yolanda; Cheng, F LU ; Isaksson, A LU ; Fransson, L A LU ; Malmström, A LU and Westergren-Thorsson, G LU (1997) In Journal of Cellular Biochemistry 64(4). p.595-604
Abstract

Binding, internalization, and degradation of 125I-labeled, antiproliferative, or nonantiproliferative heparan sulfate by human embryonic lung fibroblasts was investigated. Both L-iduronate-rich, antiproliferative heparan sulfate species as well as L-iduronate-poor, inactive ones were bound to trypsin-releasable, cell-surface sites. Both heparan sulfate types were bound with approximately the same affinity to one high-affinity site (Kd approximately 10(-8) M) and to one low-affinity site (Kd approximately 10(-6) M), respectively. Results of Hill-plot analysis suggested that the two sites are independent. Competition experiments with unlabeled glycosaminoglycans indicated that the binding sites had a selective specificity for sulfated,... (More)

Binding, internalization, and degradation of 125I-labeled, antiproliferative, or nonantiproliferative heparan sulfate by human embryonic lung fibroblasts was investigated. Both L-iduronate-rich, antiproliferative heparan sulfate species as well as L-iduronate-poor, inactive ones were bound to trypsin-releasable, cell-surface sites. Both heparan sulfate types were bound with approximately the same affinity to one high-affinity site (Kd approximately 10(-8) M) and to one low-affinity site (Kd approximately 10(-6) M), respectively. Results of Hill-plot analysis suggested that the two sites are independent. Competition experiments with unlabeled glycosaminoglycans indicated that the binding sites had a selective specificity for sulfated, L-iduronate-rich heparan sulfate. Dermatan sulfate, which is also antiproliferative, was weakly bound to the cells. The antiproliferative effects of heparan and dermatan sulfate appeared to be additive. Hence, the two glycosaminoglycans probably exert their effect through different mechanisms. At concentrations above 5 micrograms/ml (approximately 10(-7) M), heparan sulfate was taken up by human embryonic lung fibroblasts, suggesting that the low-affinity site represents an endocytosis receptor. The antiproliferative effect of L-iduronate-rich heparan sulfate species was also exerted at the same concentrations. The antiproliferative species was taken up to a greater degree than the inactive one, suggesting a requirement for internalization. However, competition experiments with dextran sulfate suggested that both the high-affinity and the low-affinity sites are involved in mediating the antiproliferative effect. Structural analysis of the inactive and active heparan sulphate preparations indicated that although sulphated L-iduronate appears essential for antiproliferative activity, it is not absolutely required for binding to the cells. Degradation of internalized heparan sulfate was analyzed by polyacrylamide gel electrophoresis using a sensitive detection technique. The inactive species was partially degraded, whereas the antiproliferative one was only marginally affected.

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published
subject
keywords
Biological Transport, Cell Division, Cells, Cultured, Female, Fibroblasts, Heparitin Sulfate, Humans, Iduronic Acid, Pregnancy, Radioligand Assay, Journal Article, Research Support, Non-U.S. Gov't
in
Journal of Cellular Biochemistry
volume
64
issue
4
pages
10 pages
publisher
Wiley-Blackwell
external identifiers
  • scopus:0030899173
ISSN
0730-2312
DOI
10.1002/(SICI)1097-4644(19970315)64:4<595::AID-JCB8>3.0.CO;2-M
language
English
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yes
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59a5dc83-17b0-4050-8aa9-90ccb131219b
date added to LUP
2017-06-27 14:17:52
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2017-07-02 05:03:54
@article{59a5dc83-17b0-4050-8aa9-90ccb131219b,
  abstract     = {<p>Binding, internalization, and degradation of 125I-labeled, antiproliferative, or nonantiproliferative heparan sulfate by human embryonic lung fibroblasts was investigated. Both L-iduronate-rich, antiproliferative heparan sulfate species as well as L-iduronate-poor, inactive ones were bound to trypsin-releasable, cell-surface sites. Both heparan sulfate types were bound with approximately the same affinity to one high-affinity site (Kd approximately 10(-8) M) and to one low-affinity site (Kd approximately 10(-6) M), respectively. Results of Hill-plot analysis suggested that the two sites are independent. Competition experiments with unlabeled glycosaminoglycans indicated that the binding sites had a selective specificity for sulfated, L-iduronate-rich heparan sulfate. Dermatan sulfate, which is also antiproliferative, was weakly bound to the cells. The antiproliferative effects of heparan and dermatan sulfate appeared to be additive. Hence, the two glycosaminoglycans probably exert their effect through different mechanisms. At concentrations above 5 micrograms/ml (approximately 10(-7) M), heparan sulfate was taken up by human embryonic lung fibroblasts, suggesting that the low-affinity site represents an endocytosis receptor. The antiproliferative effect of L-iduronate-rich heparan sulfate species was also exerted at the same concentrations. The antiproliferative species was taken up to a greater degree than the inactive one, suggesting a requirement for internalization. However, competition experiments with dextran sulfate suggested that both the high-affinity and the low-affinity sites are involved in mediating the antiproliferative effect. Structural analysis of the inactive and active heparan sulphate preparations indicated that although sulphated L-iduronate appears essential for antiproliferative activity, it is not absolutely required for binding to the cells. Degradation of internalized heparan sulfate was analyzed by polyacrylamide gel electrophoresis using a sensitive detection technique. The inactive species was partially degraded, whereas the antiproliferative one was only marginally affected.</p>},
  author       = {Arroyo-Yanguas, Yolanda and Cheng, F and Isaksson, A and Fransson, L A and Malmström, A and Westergren-Thorsson, G},
  issn         = {0730-2312},
  keyword      = {Biological Transport,Cell Division,Cells, Cultured,Female,Fibroblasts,Heparitin Sulfate,Humans,Iduronic Acid,Pregnancy,Radioligand Assay,Journal Article,Research Support, Non-U.S. Gov't},
  language     = {eng},
  month        = {03},
  number       = {4},
  pages        = {595--604},
  publisher    = {Wiley-Blackwell},
  series       = {Journal of Cellular Biochemistry},
  title        = {Binding, internalization, and degradation of antiproliferative heparan sulfate by human embryonic lung fibroblasts},
  url          = {http://dx.doi.org/10.1002/(SICI)1097-4644(19970315)64:4<595::AID-JCB8>3.0.CO;2-M},
  volume       = {64},
  year         = {1997},
}