Abstract: A novel polypeptide, designated neurotrophic factor-4 (NT-4), has been identified by PCR amplification of human genomic DNA. Provided herein is nucleic acid encoding NT-4 useful in diagnostics and in the recombinant preparation of NT-4. NT-4 is used in the treatment of nerve cells and in diagnostic assays.

Abstract: DNA isolates coding for a vascular endothelial cell growth factor may be used to produce the protein via recombinant expression systems. Such protein is useful therapeutically to treat conditions in which a selective action on the vascular endothelial cells, in the absence of excessive connective tissue proliferation, is desirable.

Abstract: The .beta.-subunit of human nerve growth factor (.beta.NGF) is prepared in essentially pure form in commercially viable quantities using recombinant DNA technology. The nucleotide sequence and vectors encoding human .beta.NGF and host cells transformed with the vectors are also provided.

Abstract: The present invention provides the identification and characterization of two components of a recombinant preparation of DNase. These components are the purified deamidated and non-deamidated human DNases. Taught herein are the separation of these components and the use of the non-deamidated species as a pharmaceutical per se, and in particular in compositions wherein the species is disclosed within a plastic vial, for use in administering to patients suffering from pulmonary distress.

Abstract: Expression levels of polypeptides in recombinant host cell culture are increased by the use of synthetic DNA sequences chosen so that the mRNA transcribed therefrom is free of secondary structure sufficient to interfere with the efficiency of mRNA translation.

Abstract: Microbial expression of an exogenous polypeptide may be inefficient if the messenger RNA has secondary structure (due to complementarity of spaced regions of the molecule) which impedes interaction with a ribosome. The occurrence of such structure can be predicted. The degeneracy of the genetic code gives freedom to alter the nucleic acid composition of the CDNA to eliminate harmful secondary structure of the MRNA.For example, bovine growth hormone (BGH) is poorly expressed by E. coli transformed with a recombinant plasmid containing the natural BGH gene. The corresponding MRNA has complementary regions at 46-51 and 73-78. Therefore a plasmid PBGH 33-4 was constructed containing a BGH gene whose upstream portion was synthesized (making use of plasmid PHGH 207-1 which contains an efficiently expressible gene for the closely related human growth hormone) so as not to cause the troublesome complementarity. E. coli transformed therewith produced BGH with-a yield of better than 10.sup.5 copies per cell.