Expression and secretion of icIL-1 receptor antagonist type II
Novel glycosylated intracellular IL-1 receptor antagonist type II (icIL-1ra-II) is expressed and secreted in mammalian cells transformed with an expression vector where icIL-1ra-II is secreted by expressing icIL-1ra-II fused to the human growth hormone signal peptide. Also disclosed are a pharmaceutical composition containing glycosylated icIL-1ra-Il as an active ingredient and a method for reducing IL-1 levels in patients having a condition involving overexpressed IL-1.
1 . An expression vector for the production of a mixture of icIL-1ra-II proteins beginning at amino acid residue position +1 and +2 from the deduced start of translation on the icIL-1ra-II coding sequence, comprising a genomic DNA sequence encoding a human growth hormone signal peptide, joined to a DNA segment encoding intracellular IL-1 receptor antagonist type II (icIL-1ra-II) and operably linked to a promoter sequence, whereby said icIL-1ra-II proteins are expressed from said promoter sequence to produce a mixture of icIL-1ra-II proteins with the amino acid sequence of SEQ ID NO:4 or SEQ ID NO:11 at the N-terminus.
2 . An isolated host cell line transformed with the expression vector of claim 1 .
3 . An isolated host cell line in accordance with claim 2 , wherein said cell is an endogenous cell of a human host.
4 . A method for producing a recombinant icIL-1ra-II comprising the steps of:
culturing a host cell line according to claim 2 to express and produce a recombinant glycosylated icIL-1ra-II;
recovering the produced recombinant glycosylated icIL-1ra-II.
5 . An isolated glycosylated icIL-1ra-II beginning at amino acid residue position +2 from the deduced start of translation on the icIL-1ra-II coding sequence and having the amino acid sequence of SEQ ID NO:11 at the N-terminus.
6 . The glycosylated icIL-1ra-II according to claim 5 having an apparent molecular weight of about 27 kDa on SDS-PAGE under reducing conditions with 15% acrylamide.
7 . The glycosylated icIL-1ra-II according to claim 5 having an apparent molecular weight of about 30 kDa on SDS-PAGE under reducing conditions with 15% acrylamide.
8 . A pharmaceutical composition, comprising the glycosylated icIL-1ra-II according to claim 5 in a therapeutically effective amount and a pharmaceutically acceptable excipient.
9 . A method for reducing the amount of IL-1 in a patient having a condition associated with overexpression of IL-1, comprising administering the pharmaceutical composition according to claim 8 to a patient in need thereof.
10 . A method for reducing the amount of IL-1 at a desired site in a human patient, comprising introducing a vector in accordance with claim 1 into appropriate endogenous human cells at the desired site to produce transformed cells which will express icIL-1ra-II at the desired site.