Abstract: The present invention comprises the epitope recognized by the human monoclonal antibody 16-18, the human tumor antigen containing this epitope, which we have identified, isolated and characterized, and anti-idiotypic antibodies to human MCA 16-88, which comprise the same epitope. The invention also relates to the use of antibodies to the antigen containing this epitope for diagnosis and monitoring of treatment of cancer and to the use of this antigen in the preparation of vaccines to elicit an immune response similar to that obtained against tumor cells containing this epitope.

Abstract: A bacteriophage directional cloning vector containing a multiple cloning site, a method for preparing cDNAs that can be cloned in a unique orientation and a bifunctional oligodeoxynucleotide linker, which creates a unique restriction site when ligated to the 3' end of cDNA fragments. The simple and efficient cDNA cloning system reduces the amount of RNA and effort required for the preparation of large directionally cloned libraries by providing a unique vector that accepts cDNA fragments in a unique 5'-3' orientation and by providing a unique bifunctional linker that facilitates the preparation of cDNA fragments that can be ligated directionally into the vector.

Abstract: An open reading frame DNA vector is presented having a promoter-translation start region, and adjacent thereto and downstream therefrom, a first coding segment having a start codon, a second coding segment coding for detectable protein, and an insertion region between said first and second coding regions having an insertion site and being of such length that the first and second coding segments are not in reading frame phase with each other. A method for the cloning and positive selection of a DNA segment having an open reading frame is also presented, as well as a tribrid protein wherein each terminal region and the mid-section is derived from a different gene, and a method of identifying and quantifying a protein or polypeptide without regard to its structure or biological function by using a DNA segment coding for said protein or polypeptide as the mid-section of the tribrid protein.