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Thromb Haemost 1988; 60(02): 255-261
DOI: 10.1055/s-0038-1647041
Original Article
Schattauer GmbH Stuttgart

The Influence of Carbohydrate Structure on the Clearance of Recombinant Tissue-Type Plasminogen Activator

A Hotchkiss
1   The Department of Pharmacological Sciences, Genentech, Inc., South San Francisco, CA, USA
,
C J Refino
1   The Department of Pharmacological Sciences, Genentech, Inc., South San Francisco, CA, USA
,
C K Leonard
2   The Department of Medicinal and Analytical Chemistry, Genentech, Inc., South San Francisco, CA, USA
,
J V O'Connor
2   The Department of Medicinal and Analytical Chemistry, Genentech, Inc., South San Francisco, CA, USA
,
C Crowley
3   The Department of Cell Genetics, Genentech, Inc., South San Francisco, CA, USA
,
J McCabe
1   The Department of Pharmacological Sciences, Genentech, Inc., South San Francisco, CA, USA
,
K Tate
4   The Department of Molecular Biology, Genentech, Inc., South San Francisco, CA, USA
,
G Nakamura
2   The Department of Medicinal and Analytical Chemistry, Genentech, Inc., South San Francisco, CA, USA
,
D Powers
4   The Department of Molecular Biology, Genentech, Inc., South San Francisco, CA, USA
,
A Levinson
4   The Department of Molecular Biology, Genentech, Inc., South San Francisco, CA, USA
,
M Mohler
1   The Department of Pharmacological Sciences, Genentech, Inc., South San Francisco, CA, USA
,
M W Spellman
4   The Department of Molecular Biology, Genentech, Inc., South San Francisco, CA, USA
› Author Affiliations
Further Information

Publication History

Received 21 March 1988

Accepted after revision 13 June 1988

Publication Date:
28 June 2018 (online)

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Summary

Modification of the carbohydrate structures of recombinant tissue-type plasminogen activator (rt-PA) can increase or decrease its rate of clearance in rabbits. When rt-PA was treated with sodium periodate to oxidize carbohydrate residues, the rate of clearance was decreased from 9.6 ± 1.9 ml min−1 kg−1 to 3.5 ± 0.6 ml min−1 kg−1 (mean ± SD, n = 5). A similar change in the clearance of rt-PA was introduced by the use of endo-β-N-acetyl- glucosaminidase H (Endo-H), which selectively removes high mannose asparagine-linked oligosaccharides; the clearance of Endo-H-treated rt-PA was 5.0 ± 0.5 ml min−1 kg−1. A mutant of rt-PA was produced with an amino acid substitution at position 117 (Asn replaced with Gin) to remove a potential glycosylation site that normally contains a high mannose structure. The clearance of this material was also decreased, similar to the periodate and Endo-H-treated rt-PA. Conversely, when rt-PA was produced in the CHO 15B cell line, which can produce only high mannose oligosaccharide structures on glycoproteins, the clearance was increased by a factor of 1.8. These results demonstrate that the removal of rt-PA from the blood depends significantly upon the nature of its oligosaccharide structures.

Keywords

Tissue-type plasminogen activator - Plasminogen activator - Pharmacokinetics - CHO 15 B cells - High mannose oligosaccharides