0000000000585775
AUTHOR
Sooghee Chang
Analysis of Epitope Spreading over an Eleven-year Period in a Patient with Systemic Lupus Erythematosus: CASE REPORT
During a period of more than eleven years serum samples of a patient with Systemic Lupus Erythematosus were collected and analyzed for anti-nuclear autoantibodies. High titer of anti-La/SS-B were detectable in all serum samples. The La/SS-B epitopes remained constant. Besides anti-La/SS-B antibodies all serum samples contained traces of anti-Ro/SS-A including anti-Ro52 and anti-Ro60 antibodies. During disease flares anti-Ro/SS A antibodies were upregulated and anti-dsDNA antibodies appeared, thus supporting the concept of an antigen driven intermolecular epitope spreading to Ro/SS-A and dsDNA.
Shuttling of the autoantigen La between nucleus and cell surface after uv irradiation of human keratinocytes.
During the past years we have established that the nuclear autoantigen La shuttles between the nucleus and the cytoplasm in tumor cells after inhibition of transcription or virus infection. We reinvestigated this shuttling using primary human keratinocytes from both healthy donors and patients with xeroderma pigmentosum. Ultraviolet irradiation resulted in both an inhibition of transcription and a translocation of La protein from the nucleus to the cytoplasm. After a prolonged inhibition of transcription La protein relocated into the nucleus and assembled with nuclear storage regions. The uv-induced shuttling included a translocation to the cell surface, where La protein colocalized with ep…
Cross-Reactivity of Antibodies Immunoadsorbed to Laminin with Recombinant Human La (SS-B) Protein
Anti-La (SS-B) antibodies cross-reacting with mouse B1 laminin were reported in sera of patients with systemic lupus erythematosus. However, the common epitope had not been characterized. Immunoblotting conditions were established, allowing detection and elution of anti-La (SS-B)/laminin cross-reacting antibodies. Antibodies adsorbed to mouse B1 laminin represented a subclass of anti-La antibodies. They strongly reacted with human full length recombinant La protein. However, they failed to react with either an N-terminal La peptide consisting of amino acids 1-192 or a C-terminal La peptide starting at methionine 223, while they still reacted with recombinant La peptides consisting of the am…