A tissue-type plasminogen activator mutant with prolonged clearance in vivo. Effect of removal of the growth factor domain.
The complete cDNA for human tissue-type plasminogen activator (t-PA) was cloned and sequenced. A mutant was constructed by using in vitro site-specific mutagenesis to delete the region encoding the growth factor domain (amino acids 51-87 inclusive). Normal and mutant t-PA species were produced using two mammalian expression systems (in human HeLa cells and mouse C127 cells). The clearance of mutant and normal t-PA from plasma was examined in vivo using a guinea pig model. Mutant t-PA derived from HeLa or C127 cells was cleared much more slowly than the cognate normal t-PA. The potential role of the growth factor domain in the recognition of t-PA by the hepatic clearance mechanism is discussed.
Browne
M J
MJ
Beecham Pharmaceuticals Research Division, Biosciences Research Centre, Epsom, Surrey, United Kingdom.
Carey
J E
JE
Chapman
C G
CG
Tyrrell
A W
AW
Entwisle
C
C
Lawrence
G M
GM
Reavy
B
B
Dodd
I
I
Esmail
A
A
Robinson
J H
JH
D000818:Animals; D001426:Bacterial Proteins; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D004262:DNA Restriction Enzymes / Q000378:metabolism; D015252:Deoxyribonucleases, Type II Site-Specific; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation; D006168:Guinea Pigs; D006801:Humans; D009154:Mutation; D013329:Structure-Activity Relationship; D010959:Tissue Plasminogen Activator / Q000097:blood / Q000235:genetics*
D001426:Bacterial Proteins; D004247:DNA; D004262:DNA Restriction Enzymes; C024404:BglII endonuclease; D015252:Deoxyribonucleases, Type II Site-Specific; D010959:Tissue Plasminogen Activator