Abstract: Disclosed is a method for the isolation and purification of polypeptides expressed in host cells by recombinant DNA techniques. A fused polypeptide is produced containing a desired polypeptide fused to additional amino acids. The additional amino acids define a leader sequence having properties exploitable in purification, a hinge region, and a cleavage site. The hinge region is cysteine-free and has a secondary structure which serves to expose the cleavage site to a selected endopeptidase. The method of the invention involves the production of a fused polypeptide which may be efficiently isolated by exploiting the properties of the leader sequence, and then efficiently cleaved at the cleavage site in an appropriate aqueous environment by virtue of the influence of the hinge on the cleavage agent/cleavage site reaction and other properties of the fused polypeptide.

Abstract: Fluorescently labeled ENP as well as methods of preparation are disclosed. Also disclosed is a method of detecting endotoxin in a liquid sample suspected of containing endotoxin, comprising admixing said liquid sample with fluorescently labeled ENP for a time sufficient to form a complex between the labeled ENP and the endotoxin, and performing fluorescence polarization experiment on the sample, wherein a change in the fluorescence polarization indicates the presence of endotoxin.

Abstract: Disclosed is a novel polypeptide useful as a leader or trailer peptide moiety in recombinant DNA protein production techniques involving fused protein methodology. The polypeptide comprises an amphiphilic helix designed at the DNA level to have hydrophilic charged amino acid residues on one side of the barrel of the helix and nonpolar amino acid residues on the other side of the barrel of the helix. When DNA encoding the helix is attached to a gene encoding a protein of interest, high level expression is achieved and inclusion bodies are spontaneously formed. The inclusion bodies may be collected and purified easily by altering the ionic strength and/or pH of media used to dissolve the inclusion bodies. After purification, the fused protein is cleaved to separate the amphiphilic helix from the product.

Abstract: Disclosed is a novel polypeptide useful as a leader or trailer peptide moiety in recombinant DNA protein production techniques involving fused protein methodology. The polypeptide comprises an amphiphilic helix designed at the DNA level to have hydrophilic charged amino acid residues on one side of the barrel of the helix and nonpolar amino acid residues on the other side of the barrel of the helix. When DNA encoding the helix is attached to a gene encoding a protein of interest, high level expression is achieved and inclusion bodies are spontaneously formed. The inclusion bodies may be collected and purified easily by altering the ionic strength and/or pH of media used to dissolve the inclusion bodies. After purification, the fused protein is cleaved to separate the amphiphilic helix from the product.

Abstract: Disclosed is a novel polypeptide useful as a leader or trailer peptide moiety in recombinant DNA protein production techniques involving fused protein methodology The polypeptide comprises an amphiphilic helix designed at the DNA level to have hydrophilic charged amino acid residues on one side of the barrel of the helix and nonpolar amino acid residues on the other side of the barrel of the helix. When DNA encoding the helix is attached to a gene encoding a protein of interest, high level expression is achieved and inclusion bodies are spontaneously formed. The inclusion bodies may be collected and purified easily by altering the ionic strength and/or pH of media used to dissolve the inclusion bodies. After purification, the fused protein is cleaved to separate the amphiphilic helix from the product.

Abstract: A matrix for implantation in a mammalian host comprising biocompatible, mineral-free, insoluble Type-I bone collagen which may be allogenic or xenogenic to the host, and which, when implanted in the host, is biodegradable. The collagen is treated with a collagen fibril modifying substance such as acidified acetonitrile, chloroform, or dichloromethane, or by heating in an aqueous environment to a temperature of 37.degree.-65.degree. C. The treated material undergoes a change in morphology involving a significant increase in its surface area as measured by various methods. Under the scanning electron microscope the material has an "oyster shell" appearance with many pits and micropores.

Abstract: Disclosed is a matrix material for implantation in a mammalian host comprising biocompatible mineral-free type I bone collagen, xenogenic to the host, and biodegradable therewithin. The matrix is manufactured from protein-extracted bone powder treated with certain swelling agents to increase its surface area and porosity. The matrix may be combined with osteogenic protein to induce reliably and reproducibly endochondral bone formation. It also can be used as a surface coat around implantable prosthetic devices to promote cellular ingrowth or as a carrier for sustained release of various therapeutic compositions.

Abstract: Disclosed is a method for the isolation and purification of polypeptides expressed in host cells by recombinant DNA techniques. A fused polypeptide is produced containing a desired polypeptide fused to additional amino acids. The additional amino acids define a leader sequence having properties exploitable in purification, a hinge region, and a cleavage site. The hinge region is cysteine-free and has a secondary structure which serves to expose the cleavage site to a selected endopeptidase. The method of the invention involves the production of a fused polypeptide which may be efficiently isolated by exploiting the properties of the leader sequence, and then efficiently cleaved at the cleavage site in an appropriate aqueous environment by virtue of the influence of the hinge on the cleavage agent/cleavage site reaction and other properties of the fused polypeptide.

Abstract: Disclosed is a matrix material for implantation in a mammalian host comprising biocompatible mineral-free type I bone collagen, xenogenic to the host, and biodegradable therewithin. The matrix is manufactured from protein-extracted bone powder treated with certain swelling agents to increase its surface area and porosity. The matrix may be combined with osteogenic protein to induce reliably and reproducibly endochondral bone formation. It also can be used as a surface coat around implantable prosthetic devices to promote cellular ingrowth or as a carrier for sustained release of various therapeutic compositions.