Wilhelm Bernhard was born November 8, 1920, in the village of Worb, Switzerland. As a youth he pursued his earliest scientific interest, astronomy, grinding his own telescope mirror to scan the sky. After completing his studies at Berne and Geneva for the M.D. degree in 1946, he served briefly in the Swiss Army as physician for ski-borne troops, scaling the heights with his patrol. In 1947 he went to Paris, France, for training in pathology where he met Professor Charles Oberling, early propounder of the viral theory of cancer. They discovered in each other a mutual boundless curiosity, zest for life, and love of history and the arts. Professor Oberling invited Dr. Bernhard to head the new laboratory of electron microscopy in Villejuif, one of the first established in France.

Some of the earliest descriptions of the ultrastructure of cell organelles (nucleolus, endoplasmic reticulum, Golgi apparatus, lysosomes, centrioles, microtubules) emanated from this laboratory, where students and guests from many countries gathered to learn and to collaborate. But during the early years, Dr. Bernhard’s primary interest was to study the neoplastic cell and the viruses known to induce certain animal tumors, with the ultimate goal of determining whether viruses could be causally linked to human cancer. Thus, between 1953 and 1966 he and his colleagues demonstrated the structure and intracellular development, first of the Rous sarcoma virus and then, successively, the viruses associated with the Shope fibroma, mouse mammary tumor, Murray-Beg avian endothelioma, avian erythroblastosis and myeloblastosis, murine leukemia, the polyoma, and SV40 viruses and adenoviruses. It was he who proposed the now established classification of types A, B, and C murine oncogenic viruses. It was he who wrote, after years of comparative studies, especially of human leukemias, that there is no specific ultrastructural change in neoplastic cells.

Dr. Bernhard’s first task at Villejuif in 1947 had been to develop procedures for obtaining sections of cells thin enough for high resolution electron microscopy. With the first premethacrylate waxes that he tested after shivering through long hours of sectioning in a cold room, he was not only able to obtain ultrathin sections but also to stain adjacent sections and demonstrate that the newly discovered granular endoplasmic reticulum was indeed the basophilic ergastoblasm of Garnier and Bouin. From that time, he eagerly sought new cytochemical techniques that would extend even further the information that could be gained from the electron microscope. With his colleagues, he pioneered in the development and utilization of electron microscope autoradiography, water-miscible embedding resins, enzymic digestion of specific components of cells, cryoultramicrotomy, immunocytochemistry with peroxidase as marker, concanavalin A labeling of cell membranes, a specific stain for DNA, and a selective stain for ribonucleoprotein.

At a time when most electron microscopists focused primarily on the myriads of structures in the cytoplasm, Dr. Bernhard attempted to decipher the ultrastructure of the nucleus. The perichromatin fibrils and their role in RNA synthesis, the phenomenon of nucleolar segregation, the existence of different types of perichromatin granules, and the formation of abnormal nuclear bodies were all described in his laboratory, using cultured cells treated with various drugs and hormones and processed by cytochemical procedures. At the time of his death, he and his colleagues were pursuing nonnucleolar transcription units and the organization of DNA in interphase nuclei.

Dr. Bernhard’s influence was felt well beyond his laboratory. He was a charter member of the Société Française de Microscopie Èlectronique and the European Cell Biology Organization. He founded and ran the highly successful European Nucleolar Workshop (now Wilhelm Bernhard Workshop on the Cell Nucleus). He was the driving force behind the annual Franco-Russian cell biology conferences, and represented the Ministère des Affaires Etrangères in scientific missions in South America, India, Japan, and South Korea. A strong advocate of the thesis that science should have no national boundaries, he visited and invited to his laboratory scientists from all parts of the world.

His influence was not limited to the world of biology. Among his friends were sculptors, poets, philosophers, and painters. He was an illuminating guide to concerts, exhibitions, and architectural gems of Paris, the antique shops of the flea market, and the churches and chateaux of the Loire region. He transformed a large quarry behind the laboratory into an extraordinary rose garden. He liked Mozart, Proust, and…. American Westerns. All who knew him were touched by his charm and elegance , and his taste for beauty and adventure.

Dr. Bernhard rose through the ranks of the Centre Nationale de Recherches Scientifique from Attaché (1948 to 1953), Chargé de Recherches (1953 to 1956), Maître de Recherches (1956 to 1961), to Directeur de Recherches (1961). Throughout this period he was Chef du Laboratoire de Microscopie Électronique at the Institut de Recherches Scientifiques sur le Cancer at Villejuif. He was named Chevalier de l’Ordre Nationale du Mérite (1973), held honorary membership in the Royal Microscopical Society, the Spanish Society of Pathology , and the Académie Leopoldina, Halle (Germany), and was awarded the title Doctor Honoris Causa by the Université de Bruxelles (1969) and by the Université de Bale (1969). He was awarded the Prix Louise Darracq (Lauréat de l’Académie des Sciences, 1957); Prix du Lauréat du Concours de la Ligue Nationale Suisse Contre le Cancer, 1960; Grand Prix Scientifique de la Ville de Paris, 1964; Prix Paul Ehrlich (with R. Dulbecco), Frankfurt, 1967; Hartmann Muller Memorial Lecturer, Zurich, 1968; Ricketts Award, University of Chicago, 1972; Schleiden Medal, Académie Leopoldina, Halle, 1976. On December 4, 1978, he received posthumously the Prix Lacassagne of the Ligue Nationale Française Contre le Cancer.