Paul Ehrlich (March 14, 1854 – August 20, 1915) was a German scientist who won the 1908 Nobel Prize in Physiology or Medicine. He is noted for his work in hematology, immunology, and chemotherapy. Ehrlich predicted autoimmunity and called it "horror autotoxicus". He coined the term "chemotherapy". The idea of a "magic bullet" is also his, and he is credited with the first empirical observation of the blood-brain barrier. 
Stillmark’s findings immediately caught the attention of Ehrlich who recognized that he could investigate certain immunologic problems with them rather than the then-popular bacterial toxins.
Ehrlich discovered that feeding small amounts of lectin containing seeds to rabbits caused partial immunity to their toxicity demonstrating lectins are also antigenic (able to induce antigen antibody reactions).
Ehrlich’s work with these lectins became the very foundation of the discipline of immunology. Since the toxins are much less toxic when given by mouth than by injection, Ehrlich was able to induce immunity by feeding mice or rabbits small amounts of the seeds.