Experimentally induced malignant lymphoma due to chronic antigen stimulation.

Animal experiments were started in 1988 with the aim of inducing malignant lymphomas. 52 guinea pigs were exposed to potassium dichromate using the TINA test (plus 39 control animals). Following the sensitization procedure, the test animals and 15 control guinea pigs were exposed daily (5 x a week) epicutaneously to the antigen up to the present time. Currently, 30 exposed and 17 control animals are still in the experiment. In 3 out of 17 post-mortem examinations, histologically evident lymphomas were found. In the control animals, no tumor has been seen. The experiments support lymphoma causation by chronic antigen stimulation. The experiments are continuing.