Inhibitory effect of immunoglobulin E production by jin-deuk-chal (Siegesbeckia orientalis)

Elevated levels of immunoglobulin (Ig) E are associated with immediate-type allergic reactions. Jin-deuk-chal is the whole plant of Siegesbeckia orientalis (SO) sL Immunization of mice with small amounts of protein antigens on alum results in several fold increases in total plasma IgE, much of it specific for the immunizing antigen. In the present study, we investigated the effect of Siegesbeckia orientalis (SO) on IgE production. SO inhibited the plasma levels of IgE induced by antigens. The effects of SO on the interleukin (IL)-4-dependent IgE response by mouse whole spleen cells were studied. IL-4 dependent IgE production of lipopolysaccharide (LPS)-stimulated whole spleen cells was inhibited by SO. In addition, using U266B I human IgE-bearing B cells, we found that SO inhibited the production of IgE activated by LPS plus IL-4. These results suggest that SO have antiallergic activity by inhibition of IgE production from B cells.