[Compensatory reactions of immune system and action of Purple Coneflower (Echinacea purpurea (L.) Moench) preparations].

The objective of the study was to investigate the mechanisms of action of Purple Coneflower (Echinacea purpurea (L.) Moench) preparations on the immune system and to define which part of the plant is the most effective as an immunostimulator.

METHODS

The extracts from overground parts and roots of Purple Coneflower were injected into rabbits at the dose of 1 ml/kg. The stimulation of T lymphocytes in vitro was tested by incubation of rabbit blood with the different concentrations of the Purple Coneflower preparation (10, 50, 100 microg/ml) and assessed by the method of spontaneous rosettes. The number of lymphocytes, which bind to heterogenic erythrocytes, was counted. In order to determine the local effect, 30 ml of Purple Coneflower preparation (95 mg of dry material/1 ml) was used for the rinsing of mouth cavity in humans. The reaction of phagocytosis was assessed by using latex particles and calculating phagocytosis activity and phagocytosis index.

RESULTS

Purple Coneflower extracts from roots were more effective phytoimmunostimulators than those from overground parts. They significantly increased in vivo the number of leucocytes and lymphocytes, especially T lymphocytes, in peripheral blood of rabbits as compared with the control group (p<0.001). The stimulation of T lymphocytes by Purple Coneflower preparation in vitro was the most pronounced at the concentration of 50 microg/ml (20.8+/-1.01% of spontaneous rosettes, p<0.001 with control). An increase in concentration till 100 microg/ml was followed by non-specific inhibition (9.16+/-1.6% of spontaneous rosettes, p>0.05 with control). Purple Coneflower preparations activated phagocytosis of neutrophils in vitro and in vivo. After rinsing mouth cavity with 30 ml of Purple Coneflower root preparation for 15 minutes, phagocytosis activity was significantly increased till 36% (p<0.05 as compared with the control (27%), where physiological solution was used for the rinsing). This local application of Purple Coneflower root preparation has significantly increased phagocytosis index up to 1.03 (p<0.02 as compared with the control index (0.65) after rinsing of the mouth cavity with physiological solution).

CONCLUSIONS

Purple Coneflower preparations from roots activate the cellular immunity and stimulate phagocytosis of neutrophils in vitro, in vivo and after rinsing of mouth cavity.