Effect of Vernonia cinerea L. and
vernolide-A on cell-mediated immune (CMI) response was studied in normal as well as
tumor-bearing BALB/c mice. Administration of V. cinerea and
vernolide-A significantly enhanced natural killer (NK) cell activity in both normal as well as
tumor-bearing animals, and the activity was observed earlier than in
tumor-bearing control animals. Antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent
complement-mediated cytotoxicity (ACC) were also enhanced significantly in both normal as well as
tumor-bearing animals after V. cinerea and
vernolide-A administration compared with untreated control
tumor-bearing animals. Extract and
vernolide-A showed a significant increase in cytotoxic T lymphocyte (CTL) production in both the in vivo and in vitro models. The level of
cytokines such as
interleukin (IL)-2 and
interferon (IFN)-γ were also enhanced by the treatment of V. cinerea and
vernolide-A in both normal as well as
tumor-bearing animals. This study demonstrated that V. cinerea extract and
vernolide-A stimulate the CTL, NK cell, ADCC, and ADCC through enhanced secretion of
IL-2 and IFN-γ.