Immunotherapy with Chinese medicinal herbs. I. Immune restoration of local xenogeneic graft-versus-host reaction in cancer patients by fractionated Astragalus membranaceus in vitro.

The in vitro immunomodulatory activity of fractions derived from Astragalus membranaceus, an herb commonly used in the practice of traditional Chinese medicine, was first screened by studying their individual effects on mononuclear cells (MNC) derived from healthy normal donors using the local xenogeneic graft-versus-host reaction (XGVHR). Sephacryl S-200 column-separated Fraction 3 (MW 20,000-25,000) along with its crude extract precursor, Fraction 7, and another crude extract derivative, Fraction 8, were equally augmentative (p less than 0.05) in their effect on MNC from normal donors. These three active fractions were further studied on MNC derived from 13 cancer patients. Using again the local XGVHR as a model assay for T-cell function, preincubation of MNC derived from cancer patients with Fraction 3 induced a significant increase in local XGVHR (compared to untreated cells) with a mean +/- SD of 151.34 +/- 46.02 mm3 vs 57.80 +/- 16.44 mm3; p less than 0.001. Fractions 7 and 8 likewise induced significant increases in local XGVHR (109.14 +/- 19.32 mm3 versus 50.91 +/- 17.39 mm3; p less than 0.001 and 119.74 +/- 18.33 mm3 versus 48.77 +/- 16.17 mm3; p less than 0.001, respectively). The augmented immune reactions which were induced by either Fraction 3 or Fraction 8 (but not by Fraction 7) in MNC derived from cancer patients, each significantly exceeded the local XGVHR observed in the untreated MNC derived from normal donor controls with a relative reference index (ratio) of 1.60 +/- 0.48 and 1.23 +/- 0.17 respectively; p less than 0.005.(ABSTRACT TRUNCATED AT 250 WORDS)