Trials in the treatment of the leukemias are sometimes based on a hypothesis, as in the case of exchange transfusion [33] or the use of antimetabolites [86]. Or they are conducted empirically as the results of chance observations, as in the case of the use of the nitrogen mustards, urethane, and the Vinca alkaloids. Or they lie between the two, aiming at making use of well established biological facts: examples are the use of ACTH, cortisone and, more recently, the antibiotics. What is true for bacteria may also perhaps be true, if not for elephants, at least for the malignant cells of mammals. It was this idea that lay behind the first attempts at treating cancer and leukemia with antibiotics. The results obtained by the use of certain substances extracted from micro-organisms (actinomycin, azaserine, mito mycin, rufocromomycin), although encouraging at times, were inconsistent. The action of rubidomycin appears to cover a wider spectrum and to be more consistent and more effective. As in the case of Homer and Christopher Columbus, the honor of having given birth to rubidomycin is claimed by more than one country and town. In fact, the same product was discovered in the same year, though quite independently, by a group of French workers [184] who described it under the name of rubidomycin, and by a group of Italian workers [87] who studied it under the name of daunomycin.

Any professional concerned with immunology will be interested in this book dedicated to the memory of Milan Hasek, former director of the Prague Institute of Experimental Biology and Genetics. Prof. Hasek was a congenial scientist and most amiable person - a personal friend of almost all leading immunologists around the world. He was displaced from his post of director in 1970, yet had a lasting impact upon his students and the group known as the Prague School of Immunogenetics. The topics covered in the contributions range from tolerance, immune network, and immunogenetics to the immunology of bacterial and viral infections. They are written by 27 of Prof. Hasek's former co-workers who emigrated to western countries around or after 1968 and became well-known and distinguished scientists in the field. The papers include their personal reflections of the Prague Institute, their impressions upon arriving abroad and their interesting experimental work since then. The book also provides a complete bibliography of their publications after leaving Czechoslovakia.