TOXIC EFFECT OF ALANTOLACTONE AND DIHYDROALANTOLACTONE IN INVITRO CULTURES OF LEUKOCYTES

Alantolactone, an allergenic sesquiterpene lactone, is toxic to leukocytes [human] in in vitro cultures. Cell (1 .times. 106 cells/ml of culture) stimulation by pokeweed mitogen (PWM) decreases with increasing amounts of terpene. A concentration of 1 .mu.g/ml of culture decreases stimulation by 50%. The reduced terpene, dihydro-11,13-alantolactone (DHA) is also toxic. A concentration of 1.7 .mu.g/ml of culture of DHA brings about a 50% decrease in stimulation. Both compounds affect cell viability as measured by dye exclusion. The toxicity of alantolactone may not be due to the presence of the .alpha.-methylene group conjugated to the carbonyl function of the .gamma.-lactone system.