Marian Elliot Koshland was born in New Haven, Connecticut on October 15, 1921 to Margarethe Smith Elliot, a teacher and Walter Elliot a hardware salesman. When she was four, her younger brother contracted typhoid fever. While her parents sat vigil at her brother's hospital bedside, two girls next door taught her to read and do math. After her brother returned home, she and her brother were kept in quarantine by her parents for the next year. Her father took the part of schoolmaster, teaching his daughter. When she went to schools she was more advanced than her peers, giving her a confidence in her ability to learn. In high school she took the hardest classes and after graduation was admitted to Vassar College, where she supported herself with scholarships and lived in a co-op dormitory. She graduated in 1942 with a B.A. in bacteriology.
After graduation she spent one year at medical school, but opted to go to the University of Chicago where she earned a M.S. in bacteriology (1943) and a Ph.D. in immunology (1949). While at the University of Chicago she worked on two projects, one was a vaccine for cholera, intended to help service men serving in the Far East and the other was working on ways to prevent the spread of disease among military recruits. In 1945 she married Daniel Koshland and went to Oak Ridge, Tennessee to be with her husband and work on the Manhattan Project. In Oak Ridge she studied the biological effects of radiation. After she and her husband graduated, in 1949, they moved to Boston, Massachusetts, where both had postdoctoral positions at Harvard. After two years they moved to Long Island, where they both worked at Brookhaven National Laboratory and in 1965 they moved to Berkeley. At Brookhaven she was initially refused a position, but in exchange for editing the publications that followed Brookhaven symposia she was able to get a laboratory and an assistant. The Koshlands had five children, the first comming while they were graduate students at the University of Chicago, the second in 1949, two years later they had twins and the youngest child was born in 1953.
Koshland's research dealt with antibodies. Antibodies are molecules that are secreted by immune cells that attach to molecules that are foreign to the body and signal the immune system's other cells to destroy them. In the 1950's at Brookhaven, Koshland determined that there were more than one type of antibodies. She discovered that immune cells that protect mucosal cells (cells that compose outer layers of tissue, exposed to an environment, in the stomach or lungs for example) secrete a different type of antibody than the immune cells that circulate in the blood. Later, during the 1960s, she determined the amino acid structure of antibodies that bind to different pathogens is different. At the time it was believed that antibodies could bind to different things by means of different protein folds. She proved that it was different amino acids in the structure of antibodies that give them the ability to bind to different things. In the 1970s she identified a antibody protein called the j-chain (or joining chain) that allows antibodies to assemble into multiple units. The antibody secreted by circulating immune cells (called IgG) is composed of four protein molecules and has only two spaces where it binds to another protein. Some antibody complexes are larger and as many as five or six of these IgG-like units (composed of four protein molecules with two binding spots) which give them as many as ten or twelve spots to bind foreign molecules and some use this j-chain to put more than one IgG-like unit together (for an article about the structure of the different types of antibodies go here).
In 1991 Koshland was elected to the National Academy of Science. She served as the chair of the U.C. Berkeley Department of Immunology and Bacteriology from 1981 to 1989 and she has been awarded numerous honorary degrees.
She died of lung cancer on October 28, 1996.
Guyer, Ruth Levey; "Marian Elliot Koshland"; Biographical Memoirs Vol. 90; National Academy Press; 2009
Saunders, Robert; Press Release on the death of Marian Koshland; November 6, 1997
Wasserman, Elga; The Door in the Dream: Conversations with Eminent Women in Science; Joseph Henry Press; 2002