Abstract: | When subjected to ion exchange chromatography on QAE-Sephadex A-50 or gel filtration of Sephadex G-200 under conditions that cause the dissociation of immune complexes at pH 4.05, immunoglobulins both from serum and its immunoglobulin fraction increase their interaction with charged antigens as native DNA and cardiolipin. Ion exchange chromatography also leads to the deaggregation of complexes. It was demonstrated that immunoglobulins bind DNA molecule through its F(ab)2 fragments. Based on data obtained, the suggestion was made that interaction between immunoglobulins and charged serum biopolymers is an important factor in humoral immunity regulation. Namely, high specificity of immunological reactions may be supported by elimination of non-specific binding provided electrostatic interactions from all the potential spectrum of antigen-antibody reactions. |