Immunomodulatory Potential of Herbal Formulations Containing Seeds of Nigella sativa   Linn

Immunostimulation counteracts immunosuppression, thereby playing a role in re-establishing body equilibrium. Plants with immunostimulatory activities are used as an alternative therapy for a variety of diseases, including impaired immune responses derived from infections, physical and psychological stresses, alcoholism, and environmental damages. Several lines of evidences have suggested that Nigella sativa displays a remarkable array of biochemical, immunological, and pharmacological actions. The present study investigated different formulations of N. sativa seed used as alternative medicines for chronic and immunosuppressive conditions in Nigeria. Four different formulations of N. sativa seed as a major component were analyzed for their immuno¬modulatory properties. Freshly isolated peripheral blood mononuclear cells were cultured in the presence of test samples as well as the T-cell mitogen phytohaemagglutinin. Cell viability and proliferation were determined using trypan blue dye exclusion method. The proliferative activity of test samples reached the peak at 72 h after incubation, and the best activity was achieved with 4,000-fold dilution of the original samples. The effect was sustained even after sample removal, and 2.2- to 3.6-fold increase of viable cell number was observed at the end of the experiment. These results suggest that the formulations have potential for enhancing cellular immunity alongside other therapeutic functions

Keywords
T-lymphocyte stimulation; Nigella sativa; chronic immunosuppressive conditions; immunomodulatory activity; peripheral blood mononuclear cells