Selective priming of Th1-mediated antigen-specific immune responses following oral administration of mixed prescriptions of traditional Korean medicines

Background: In previous studies, we showed that oral administration of traditional Korean medicines, Soamsan (SA) and Bo-yang-hwan-o-tang (BHT), modulated antigen-specific immune responses in mice. Methods: We attempted to strengthen cell-mediated immune responses in mice using two mixed prescriptions composed mainly of components used in SA and/or BHT. The effect of oral administration of the medicines on the induction of antigen-specific immune responses was investigated using hen egg-white lysozyme (HEL) as a model antigen system. Results: Following oral administration, HEL-specific cellular immune responses were enhanced in HEL low-responder mice, and the concentrations of gamma interferon (IFN-γ), but not interleukin (IL)-4, increased significantly. In addition, the prescriptions decreased the level of HEL-specific antibodies of the immunoglobulin (Ig)G1 subtype, which is associated with helper T lymphocyte (Th2) cell stimulation. Moreover, the presence of the medicines in vitro significantly increased IFN-γ production from mouse splenocytes, and the magnitude of the increase was closely associated with glycoprotein concentrations. Conclusions: The Korean prescriptions enhanced anti-HEL-specific cellular immune responses by selectively priming specific subtypes of the helper T cell population. Consequently, they might be useful therapy for patients who need enhanced Th1, or to suppress Th2 immune responses.