Antibody Theory

Merrill W. Chase, 98, Scientist Who Advanced Immunology

By ANAHAD O'CONNOR

Published: January 22, 2004

Dr. Merrill W. Chase, an immunologist whose research on white blood cells helped undermine the longstanding belief that antibodies alone protected the body from disease and micro-organisms, died on Jan. 5 at his home in New York City, according to the Rockefeller University, where he worked for 70 years. He was 98.

Dr. Chase made his landmark discovery in the early 1940's while working with Dr. Karl Landsteiner, a Nobel laureate recognized for his work identifying the human blood groups. At the time, experts believed that the body mounted its attacks against pathogens primarily through antibodies circulating in the blood stream, known as humoral immunity.

But Dr. Chase, working in his laboratory, stumbled upon something that appeared to shatter that widespread tenet.

As he tried to immunize a guinea pig against a disease using antibodies he had extracted from a second pig, he found that blood serum did not work as the transfer agent.

Not until he used white blood cells did the immunity carry over to the other guinea pig, providing solid evidence that it could not be antibodies alone orchestrating the body's immune response.

Dr. Chase had uncovered the second arm of the immune system, or cell-mediated immunity. His finding became the groundwork for later research that pinpointed B cells, T cells and other types of white blood cells as the body's central safeguards against infection.

''This was a major discovery because everyone now thinks of the immune response in two parts, and in many instances it's the cellular components that are more important,'' said Dr. Michel Nussenzweig, a professor of immunology at Rockefeller. ''Before Chase, there was only humoral immunity. After him, there was humoral and cellular immunity.''

Dr. Chase's breakthrough generated little interest at the time, but it set in motion the research that helped redefine the fundamental nature of the immune system.

''So many areas of medicine rely on this type of reaction that he clearly distinguished as not being antibody mediated,'' said Dr. Ralph Steinman, a professor of cellular physiology and immunology at Rockefeller. ''People never anticipated that there would be something other than antibodies. It was an amazing finding.''

Born in Providence, R.I., in 1905, Merrill Wallace Chase earned his bachelor's degree and doctorate from Brown. He taught biology there for a year, before joining the faculty at Rockefeller in 1932 as an assistant to Dr. Landsteiner. He has published at least 150 scientific papers.

In 1975, he was elected to the National Academy of Sciences.

Dr. Chase, who lived in Manhattan, was married twice, first to Edith Steele Bowen, who died in 1961, and then to Cynthia Hambury Pierce, who died in 1997. He is survived by a son, John, of West Hills, Calif.; a daughter, Nancy Chase Cowles, of Redding, Conn.; five grandchildren; and four great-grandchildren.

http://www.nytimes.com/2004/01/22/nyregion/merrill-w-chase-98-scientist-who-advanced-immunology.html