Abstract
IGFBPs play an important role in IGF biological actions by modulating IGF binding to its receptors. The major IGFBP in serum is IGFBP-3, which transports 70-90% of the circulating IGFs. In target cell systems, it sequesters IGFs and inhibits their hormonal actions, but may potentiate IGF activity or exert IGF-independent effects under specific conditions. IGFBP-3 can be modified by IGFBP-3 proteases, which degrade it into smaller fragments. IGFBP-3 fragments generated by proteolysis have reduced affinity for IGFs, thereby modifying IGF action. To study IGFBP-3 fragments in vivo and in vitro, we constructed six different IGFBP-3 fragments by use of a baculovirus expression system and generated 8 different monoclonal IGFBP-3 antibodies. Based on the known cleavage sitos of IGFBP-3 for PSA, MMPs, and the predicted plasmin cleavage sites, we expressed a N-terminal IGFBP-31- 97 fragment and a C-terminal IGFBP-398-264 fragment. By stepwise truncation from the C- lerminal end, we created IGFBP-398-232, IGFBP- 398-206, IGFBP-398-179, and IGFBP-398-159. A strong recognition of the C- terminus and the intermediate parts of IGFBP-3 by six antibodies was found. Four of these mAbs were able to recognize the intermediate fragment alone. Two mAbs were found to immunorcact only with the N-terminal IGFBP-3 fragment and two additional mAbs recognized the N- as well as the C-terminal parts and lacked immunoreactivity for the intermediate part of IGFBP-3. The 15 kDa IGFBP-3 fragment resulting from plasmin digestion was found to only react with N-terminal antibodies, while the 29 kDa fragment in pregnancy serum reacted with both N- and C-terminal antibodies. Thus, these mAbs will be useful tools to determine whether IGFBP-3 fragments found in vivo derive from either the N- or C-terminal domains of IGFBP-3.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2368-2370 |
| Number of pages | 3 |
| Journal | Journal of Clinical Endocrinology and Metabolism |
| Volume | 82 |
| Issue number | 7 |
| DOIs | |
| State | Published - 1997 |
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ASJC Scopus subject areas
- Biochemistry
- Endocrinology, Diabetes and Metabolism
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Synthesis of IGFBP-3 fragments in a baculovirus system and characterization of monoclonal anti-IGFBP-3 antibodies. / Vorwerk, Peter; Oh, Youngman; Lee, Phillip D K; Khare, Aruna; Rosenfeld, Ronald (Ron).
In: Journal of Clinical Endocrinology and Metabolism, Vol. 82, No. 7, 1997, p. 2368-2370.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Synthesis of IGFBP-3 fragments in a baculovirus system and characterization of monoclonal anti-IGFBP-3 antibodies
AU - Vorwerk, Peter
AU - Oh, Youngman
AU - Lee, Phillip D K
AU - Khare, Aruna
AU - Rosenfeld, Ronald (Ron)
PY - 1997
Y1 - 1997
N2 - IGFBPs play an important role in IGF biological actions by modulating IGF binding to its receptors. The major IGFBP in serum is IGFBP-3, which transports 70-90% of the circulating IGFs. In target cell systems, it sequesters IGFs and inhibits their hormonal actions, but may potentiate IGF activity or exert IGF-independent effects under specific conditions. IGFBP-3 can be modified by IGFBP-3 proteases, which degrade it into smaller fragments. IGFBP-3 fragments generated by proteolysis have reduced affinity for IGFs, thereby modifying IGF action. To study IGFBP-3 fragments in vivo and in vitro, we constructed six different IGFBP-3 fragments by use of a baculovirus expression system and generated 8 different monoclonal IGFBP-3 antibodies. Based on the known cleavage sitos of IGFBP-3 for PSA, MMPs, and the predicted plasmin cleavage sites, we expressed a N-terminal IGFBP-31- 97 fragment and a C-terminal IGFBP-398-264 fragment. By stepwise truncation from the C- lerminal end, we created IGFBP-398-232, IGFBP- 398-206, IGFBP-398-179, and IGFBP-398-159. A strong recognition of the C- terminus and the intermediate parts of IGFBP-3 by six antibodies was found. Four of these mAbs were able to recognize the intermediate fragment alone. Two mAbs were found to immunorcact only with the N-terminal IGFBP-3 fragment and two additional mAbs recognized the N- as well as the C-terminal parts and lacked immunoreactivity for the intermediate part of IGFBP-3. The 15 kDa IGFBP-3 fragment resulting from plasmin digestion was found to only react with N-terminal antibodies, while the 29 kDa fragment in pregnancy serum reacted with both N- and C-terminal antibodies. Thus, these mAbs will be useful tools to determine whether IGFBP-3 fragments found in vivo derive from either the N- or C-terminal domains of IGFBP-3.
AB - IGFBPs play an important role in IGF biological actions by modulating IGF binding to its receptors. The major IGFBP in serum is IGFBP-3, which transports 70-90% of the circulating IGFs. In target cell systems, it sequesters IGFs and inhibits their hormonal actions, but may potentiate IGF activity or exert IGF-independent effects under specific conditions. IGFBP-3 can be modified by IGFBP-3 proteases, which degrade it into smaller fragments. IGFBP-3 fragments generated by proteolysis have reduced affinity for IGFs, thereby modifying IGF action. To study IGFBP-3 fragments in vivo and in vitro, we constructed six different IGFBP-3 fragments by use of a baculovirus expression system and generated 8 different monoclonal IGFBP-3 antibodies. Based on the known cleavage sitos of IGFBP-3 for PSA, MMPs, and the predicted plasmin cleavage sites, we expressed a N-terminal IGFBP-31- 97 fragment and a C-terminal IGFBP-398-264 fragment. By stepwise truncation from the C- lerminal end, we created IGFBP-398-232, IGFBP- 398-206, IGFBP-398-179, and IGFBP-398-159. A strong recognition of the C- terminus and the intermediate parts of IGFBP-3 by six antibodies was found. Four of these mAbs were able to recognize the intermediate fragment alone. Two mAbs were found to immunorcact only with the N-terminal IGFBP-3 fragment and two additional mAbs recognized the N- as well as the C-terminal parts and lacked immunoreactivity for the intermediate part of IGFBP-3. The 15 kDa IGFBP-3 fragment resulting from plasmin digestion was found to only react with N-terminal antibodies, while the 29 kDa fragment in pregnancy serum reacted with both N- and C-terminal antibodies. Thus, these mAbs will be useful tools to determine whether IGFBP-3 fragments found in vivo derive from either the N- or C-terminal domains of IGFBP-3.
UR - http://www.scopus.com/inward/record.url?scp=0030854004&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030854004&partnerID=8YFLogxK
U2 - 10.1210/jc.82.7.2368
DO - 10.1210/jc.82.7.2368
M3 - Article
C2 - 9215321
AN - SCOPUS:0030854004
VL - 82
SP - 2368
EP - 2370
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 7
ER -