Dr. Altman receiving Prize in presence of Their Majesties
On 26 November, the 28th annual ceremony for awarding the International Prize for Biology was held in the presence of Their Majesties the Emperor and Empress at the Japan Academy, located in Ueno Park, Tokyo. The ceremony was organized by the Committee on the International Prize for Biology, chaired by Dr. Takashi Sugimura, vice president of the Japan Academy.
At the ceremony, an opening message was delivered by Dr. Sugimura and a report on the selection process provided by Dr. Noriyuki Satoh, chair of this year’s Selection Committee, after which the Prize and an Imperial gift were presented to this year’s awardee, Dr. Joseph Altman, Professor Emeritus, Purdue University, USA.
Congratulatory remarks followed from the Prime Minister (read by Mr. Hirokazu Shiba, Deputy Chief Cabinet Secretary) and from Ms. Makiko Tanaka, Minister of Education, Culture, Sports, Science and Technology (MEXT). The ceremony concluded with an acceptance address from Dr. Altman.
Dr. Altman talking with Emperor Akihito
At the reception following the ceremony, a congenial atmosphere prevailed with Their Majesties and Dr. Altman engaging in amicable conversation with each other and with the guests who included embassy representatives and the Prize Committee members.
The International Prize for Biology Commemorative Symposium and Lecture on “Neurogenesis throughout Life” was held on 28-29 November at RIKEN Center for Developmental Biology (CDB), Kobe.
Acceptance Address by Dr. Joseph Altman
I greatly appreciate to be awarded the 2012 International Prize for Biology and thus join the roster of distinguished scientists who received this honor in the preceding years. I am grateful to Their Majesties the Emperor and the Empress not only for granting this honor but also for their appreciation and great interest in the advancement of science as a worldwide international enterprise. I also wish to thank the Japan Society for the Promotion of Science, and the Selection Committee for giving me this award. And I will take this opportunity to thank my wife and collaborator, Dr. Shirley Bayer-Altman, who played such an important role in the research for which this award is given and who has provided me with moral support for over 40 years.
Our research began in the early 1960s with a simple experiment, the study of gliacell proliferation following experimentally induced brain injury. At that time a new technique, autoradiography, became available to study cell proliferation. By injecting adult rats with radioactively labeled thymidine, a specific precursor of DNA, it became possible to visualize multiplying cells. To our surprise we found that in addition to the labeled glia cells in the vicinity of the lesion site, there were also some labeled neurons some distance from the damaged area. This was quite puzzling since we were taught that no neurons are generated after birth. We proceeded to study the pattern of neuron labeling in normal rats. In the succeeding years we established that the precursors of granule cells (microneurons) of the cerebellar cortex were multiplying for several weeks after birth. So were the precursors of granule cells of the hippocampal dentate gyrus and the olfactory bulb. Indeed granule cells in the dentate gyrus and olfactory bulb were also labeled throughout adulthood. Our studies indicated that the precursor cells which give rise to specific populations of granule cells reside in specialized germinal matrices. In the cerebellum this matrix is the external germinal layer; in the hippocampus, the subgranular zone; and in the case of the olfactory bulb, the precursor cells originate in the cortical subventricular zone and reach the bulb by way of the rostral migratory stream.
To substantiate that the labeled cells are truly new neurons, we proceeded to use alternate techniques. One of them was the simple descriptive procedure of counting identifiable granule cells in the cerebellum, hippocampus and the olfactory bulb as a function of postnatal age; the results confirmed that the number of granule cells increases with age in all these brain areas. We also used exposure to radiation as an experimental technique because multiplying cells are extremely radiosensitive. We selectively exposed the cerebellum, hippocampus and olfactory bulbs of baby rats at different ages to low-level x-rays. The experiments indicated that cerebellar irradiation destroyed the external granular layer, and depending on the time of the exposure this germinal matrix succeeded or failed to regenerate. Failure of regeneration caused a reduction in the granule cell population and led to locomotor and postural abnormalities similar to those produced by cerebellar pathologies. Early hippocampal irradiation led to a paucity of granule cells and that led to such abnormalities as hyperactivity and attentional and learning deficits.
Although our research created considerable interest in the 1960s, our peers ignored our demonstrations for some time, as they did Michael Kaplan’s confirmatory studies in the mid-1970s. Fernando Nottebohm and his associates rekindled interest in the problem of adult neurogenesis in the 1980s, and by the 1990s the problem became the subject of intensive research by Elizabeth Gould, Gerd Kempermann, Tatsunori Seki, and other investigators. We are extremely pleased in the growing worldwide interest in the subject, including here in Japan. The demonstration of postnatal and adult neurogenesis suggests that the structural organization of the brain is more dynamic than it was assumed in the past. It remains a challenging experimental and clinical task to determine to what extent that dynamism offers potential remedies for the many aberrations and pathologies of brain function.
Let me end by thanking again Their Majesties and the Japan Society for the Promotion of Science for this great honor.
- General Affairs Division