1985/04/01 by J C Chambers, J. D. Keene · 4 citations
Medicine · Immunology and Microbiology · #Systemic Lupus Erythematosus Research #Monoclonal and Polyclonal Antibodies Research #T-cell and B-cell Immunology #Complementary DNA #Molecular biology #Antigen #Recombinant DNA #Biology #cDNA library #HeLa #In vitro #Gene #Biochemistry #Genetics
paper · doi:10.1073/pnas.82.7.2115
openalex publication_date 1985/04/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/22
Several cDNA clones of the La antigen recognized by certain lupus autoantibodies were isolated from lambda gt11 expression libraries made from human liver. Recombinant clones were used to hybrid-select HeLa cell mRNA that was subsequently translated in vitro into a single protein species that comigrated with HeLa cell La protein. The in vitro translated protein was reactive with anti-La patient sera and was identical to the authentic La protein by peptide mapping. By analyzing overlapping cDNA clones, we mapped an antigenic site of La protein at the terminal 12% of the carboxyl end of the molecule. Within this region we identified a unique decapeptide of high hydrophilicity that may constitute a La antigenic determinant. We further demonstrated that the La antigen expressed from the recombinant clones can be used in a definitive enzyme-linked assay (ELISA) for the classification of sera from patients with systemic lupus erythematosus.