ABSTRACT
The immune system is highly controlled and can distinguish self from non-self components of the body. Immunostimulants could be useful in treating all conditions of immunodeficiency or viral and bacterial infections. These drugs have been used in cancer therapy as adjuvants. Most natural products that exhibit immunostimulant activity mainly exert their functions by acting on innate immunity. Despite the development of pharmaceutical and chemical factories in the second half of the twentieth century, nature continues to be an invaluable source of medicines. Natural medicine may particularly benefit the field of immunostimulation, which is still poorly represented by conventional medicines. Thus, the discovery and testing of new natural products can greatly improve the prognosis of immune-depressed patients that require additional therapy beyond conventional medicine. Saponins are natural surface-active glycosides that are produced mainly by plants that possess many pharmacological properties, including immunostimulatory effects.
