Susumu Tonegawa, a Japanese-born geneticist at the Massachusetts Institute of Technology, was awarded the 1987 Nobel Prize for Medicine on Monday for explaining how the immune system is able to make a seemingly limitless variety of antibodies to protect the body from foreign substances.
The $340,000 prize capped more than 11 years of research by Tonegawa, 48, that has broad applications for understanding diseases that attack the immune system, for countering the body's natural response to reject transplanted organs and for improving therapy for allergies and other immunological disorders.
"I hope the information we got will be useful in developing responses to a number of diseases, including cancer and possibly even AIDS" (acquired immune deficiency syndrome), Tonegawa told a news conference in Newton, Mass. He was accompanied by his wife, Mayumi, and their 9-month-old son, Hidde.
"If we understand how the (immune) system works, that information will be helpful in understanding what (can go) wrong with it," he said.
Tonegawa is the first Nobel winner required by the Internal Revenue Service to pay taxes on his prize. The tax revision law enacted last year provides that scientific and literary awards are subject to federal taxation unless the recipients give their winnings to charity.
Tonegawa said he was surprised that he did not share the award with other scientists who also have been engaged in studying antibody production.
Just last month, he shared the prestigious Lasker Medical Research Award with Leroy Hood of Caltech and Philip Leder of Harvard for their work that clarified the relationship between DNA and antibody production. The Lasker citation recognized Tonegawa for "his brilliant concepts and experimental achievements in applying molecular biology to the analysis and understanding of the genetics of antibody diversity."
In Stockholm, where this year's award winner was announced, Prof. Goran Holm of the Karolinska Institute called Tonegawa's research "an extremely vital discovery in medical science."
"The genetic side of antibody research was a complete mystery to us all when Tonegawa started his work," said Prof. Bengt Samuelsson, president of the Karolinska Institute. "He was the only player in the field between 1976 and 1978. The work was truly unique."
In the past, the Nobel Prize often has been given to scientists long after they had made their winning discovery. But one member of this year's Nobel committee, Nils Ringertz, said that "it is more fun to give the prize to a dynamic researcher who is at the height of his powers."
He said he does not believe that Tonegawa will rest on his laurels.
"Tonegawa is a natural force who will continue to work, whatever prizes he gets," Ringertz said.
The basic role of the immune system is to recognize each of the disease-causing organisms and other harmful substances with which people come in contact during a lifetime and to make protective antibodies against them.
Almost from birth, people with healthy immune systems have antibodies that have been pre-programmed against each of hundreds of millions of such potential invaders--long before the individual actually encounters the invader.
The structure of antibodies is determined by genes. Tonegawa earned the Nobel Prize for being the first to describe how the body's limited number of genes can direct the manufacture of hundreds of millions of different antibodies.
Determined by Genes
The answer is that the cells that make antibodies contain bits and pieces of perhaps several hundred genes, and these genes are continuously being shuffled in each of hundreds of millions of cells to form an enormously diverse array of antibodies, which can counteract any invader with which they come into contact.
Tonegawa said he still remembers the day that he walked into his lab and saw the results of an experiment showing that one gene, by shuffling its internal parts, can make many different antibodies.
"I was very glad that it worked. But it took months to realize what the impact of that was. I guess these things come gradually," he said.
Tonegawa is the first Japanese to earn a Nobel Prize in medicine.
He graduated from Kyoto University in Japan in 1963. In 1968, he received a doctorate from UC San Diego and later was a research fellow at the Salk Institute in La Jolla, where he worked under Renato Dulbecco, a Nobel laureate.
In 1971, he moved to a research post in Basel, Switzerland, where he made his major discovery. He has been at MIT since 1981.