Studies on antigen specifity of immunoreactive arabinogalactan proteins extracted from Baptisia tinctoria and Echinacea purpurea.

In a series of experiments the cross-reactivity of antibodies raised against arabinogalactan proteins from Baptisia tinctoria and Echinacea purpurea was studied in order to prove the antigen specificity of the extracted glycoproteins/polysaccharides. Using the antigen-antibody reaction in a competitive ELISA it was evident that antibodies against glycoproteins from Baptisia tinctoria were specific because none of the other antigens like those from Echinacea purpurea, Thuja occidentalis, arabinogalactan from larch, LPS from E. coli 055:B5, and from Salmonella typhimurium were able to inhibit the antigen-antibody reaction. The same results were obtained from ELISA experiments with Echinacea purpurea. From these studies it was concluded that the antigenic regions of immunoreactive proteins from both medicinal plants show structural differences.