EVALUATION OF THE IMMUNOMODULATORY ACTIVITY OF THE METHANOL EXTRACT OF ALCHEMILLA KIWUENSIS ENGL.
Many infections just like many other diseases today are based on an imbalance in immunological processes. Use of immunomodulatory substances could help in the re-establishment of the immunological balance. Thus, the objective of the present study was to explore the immunomodulatory activity of Alchemilla kiwuensis, a cameroonian medicinal plant used in folk medicine for treatment of anemia and infectious diseases. The immunomodulatory activity was evaluated in in-vitro cultures by measuring the effect of the extract on nitric oxide production by macrophages, the proliferation of lymphocytes and the cytotoxic effect on macrophages. Different doses of the A. kiwuensis extract were evaluated in-vivo in mice for the induction of delayed-type hypersensitivity (DTH) and for the ability to reverse the myelosuppression induced by cyclophosphamide.The extract inhibited nitric oxide production by macrophages, and had a proliferative effect on lymphocytes in culture. In-vivo, the plant extract induced a significant delayed-type hypersensitivity (DTH) reaction on mice treated with 100 mg/kg of extract, and also showed a significant increase in blood cell counts, packed cell volume (PCV) and relative weight of the spleen. These results suggest that the A. kiwuensis methanol extract possesses immunostimulatory activity. These finding would probably justify the use of this plant extract in the treatment of infectious diseases in folk medicine in many parts of Cameroon and elsewhere.