Augmentation of natural killer cell activity in vivo against tumour cells by some wild plants from Jordan

Twelve aqueous extracts prepared from Jordanian plants that are currently u sed in traditional medicine to treat various types of cancer were tested in mice for their augmentation of natural killer cells in vivo in generating cytotoxicity against YAC tumour targets, After 1 week of oral administratio n of aqueous extracts of fresh Nigella sativum (N,s,) seeds and Allium sati vum (A,s,) bulbs significant augmentation of splenic natural killer (NK) ce lls (62.3% +/- 6.4% and 52.6% +/- 5.4% cytotoxicity, respectively), was obt ained in comparison with spontaneous activity (24.5% +/- 1.6%) at 200:1 eff ector:target ratio. Onopordum acanthium (O,a,) stem and leaves and Allium c epa (A,c,) bulbs showed intermediate augmentation (38.6% +/- 3.8% and 30.6% +/- 3.4% cytotoxicity, respectively) while the rest showed insignificant a ugmentation activity, The fresh aqueous extract of a mixture of the plants with high and intermediate activity showed little insignificant augmentatio n activity (72.7% +/- 6.7% cytotoxicity) of NK cells compared with that obt ained with each plant alone. Copyright (C) 2001 John Whey & Sons, Ltd.