IMMUNE CAPILLARY ELECTROPHORESIS FOR THE CHARACTERIZATION OF A MONOCLONAL-ANTIBODY AGAINST DNA

A monoclonal antibody against DNA established from a mouse strain that spontaneously develops systemic lupus erythematosus was characterized by migration shift immune-capillary electrophoresis. The minimal size for DNA binding antibody was >16 bases and the interaction with a dou ble-stranded 32-mer oligonucleotide was almost one order of magnitude stronger than the interaction with a single-stranded oligonucleotide. The binding was highly dependent on the ionic strength conditions with an increase in binding with a decrease in ionic strength. The estimat e of the dissociation constant for the antibody binding of a single-st randed 32-mer oligonucleotide was 0.62 mu M at pH 7.90. This value was in good agreement with the value of 0.44 mu M measured by an independ ent method using biosensor (surface plasmon resonance) technology.