摘要:
A hybrid polypeptide composed of an identification peptide and a desired functional protein are produced by recombinant DNA techniques. A DNA expression vector is constructed that includes segments of DNA coding for the identification peptide and the desired functional protein. The identification peptide consists of a highly antigenic N-terminal portion and a C-terminal linking portion that connects the identification peptide to the N-terminal of the functional protein. The linking portion of the identification peptide is cleavable at a specific amino acid residue adjacent the functional protein by use of a sequence specific proteolytic enzyme or chemical proteolytic agent. The hybrid polypeptide expressed by the host cells transformed by the cloning vector is removed therefrom and purfied by affinity chromatography techniques by use of an immobilized ligand specific to the antigenic portion of the identification peptide. The protein is then cleaved from the isolated hybrid polypeptide with an appropriate proteolic enzyme or chemical agent, thereby releasing the mature functional protein in highly purified, highly active state.
摘要:
A hybrid polypeptide composed of an identification peptide and a desired functional protein are produced by recombinant DNA techniques. A DNA expression vector is constructed that includes segments of DNA coding for the identification peptide and the desired functional protein. The identification peptide consists of a highly antigenic N-terminal portion and a C-terminal linking portion that connects the identification peptide to the N-terminal of the functional protein. The linking portion of the identification peptide is cleavable at a specific amino acid residue adjacent the functional protein by use of a sequence specific proteolytic enzyme or chemical proteolytic agent. The hybrid polypeptide expressed by the host cells transformed by the cloning vector is removed therefrom and purified by affinity chromatography techniques by use of an immobilized ligand specific to the antigenic portion of the identification peptide. The protein is then cleaved from the isolated hybrid polypeptide with an appropriate proteolic enzyme or chemical agent, thereby releasing the mature functional protein in highly purified, highly active state.
摘要:
Double-stranded cDNA is prepared from polyadenylated RNA extracted from activated human peripheral blood adherent mononuclear cells. The cDNA is inserted within a plasmid vector and then the recombinant plasmid employed to transform an appropriate host. Transformed hosts are identified and grouped into pools. Plasmid DNA prepared from these pools is hybridized with a labeled, synthetic oligonucleotide probe corresponding to a portion of the amino acid sequence of the interleukin 1 protein. Pools of host cells that provide a positive signal to the probe are identified, plated out and then employed in direct bacterial colony hybridization with the same probe, thereby to isolate the particular positive colony. Plasmid DNA is prepared from this colony and characterized by restriction enzyme mapping and sequencing by chain-termination method. The coding region for the IL-1 gene is inserted into a shuttle vector for amplification of the vector followed by expression of functional IL-1.
摘要:
Interleukin 1 has been purified by use of various techniques including ion exchange chromatography and dye-ligand affinity chromatography. By these techniques, interleukin 1 has been purified to homogeneity. The high purification of interleukin 1 has enabled the amino acid composition of this protein to be ascertained and its amino acid sequence to be partially determined.
摘要:
Colony stimulating factor derived from malignant cells has been purified by use of various techniques including multiple high performance liquid chromotography steps. By this technique, colony stimulating factor has been resolved into distinct species, and one of the species denominated as CSF-2A, has been purified to homogeneity. The high purification of the CSF-2A has enabled the amino acid composition of this protein molecule to be partially sequenced with an automated sequencer.
摘要:
A metalloprotease that converts TNF-&agr; from the 26 kD cell form to the 17 kD form has been isolated and purified and the cDNA sequence known. In particular, the protease has a molecular weight of approximately 80 kD. The isolated and purified protease is useful for designing an inhibitor thereof, and may find use as a therapeutic agent. Assays for detecting the protease-inhibiting activity of a molecule are also an aspect of the invention.
摘要:
Mammalian Interleukin-4 receptor proteins, DNAs and expression vectors encoding mammalian IL-4 receptors, and processes for producing mammalian IL-4 receptors as products of cell culture, are disclosed. A method for suppressing an IL-4-dependent immune or inflammatory response in a mammal, including a human, by administering an effective amount of soluble IL-4 receptor (sIL-4R) and a suitable diluent or carrier.
摘要:
Interleukin-2 receptor derived from normal and malignant cells has been purified by use of various techniques including affinity chromotography in conjunction with a monoclonal antibody directed to the receptor. Purification also involved reversed phased high performance liquid chromotography. By these techniques, interleukin-2 receptor has been purified to homogeneity. The high purification of the interleukin-2 receptor has enabled this protein molecule to be partially sequenced.