Fritz Bach worked in genetics, immunology and vascular biology, but was widely regarded as one of the pioneers in transplant research.
He developed a cellular test to facilitate the first successful bone marrow transplants, which subsequently enabled hundreds of thousands worldwide to live normal healthy lives. He further developed techniques to improve patients' chances of surviving bone marrow and organ transplants.
Although Georges Mathé, a French oncologist, performed the first bone marrow transplants in 1959 on five Yugoslavian nuclear workers whose own marrow had been damaged by radiation, these transplants failed. This became a recurring problem with the procedure. Bach decided to set up a mini-transplant in a test tube and his test paved the way for assessing immune compatibility between individuals; the more likely, the less the possibility of rejection. His seminal work took cells from the patient who needed a transplant and cells from a potential donor and mixed them together; he showed that they reacted to one another in a similar way to how one would expect them to react in the transplant setting. He called his technique the Mixed Leukocyte Culture Test, or MLC, and in the 1960s began to apply his approach to bone marrow.
Doctors began to apply the technique to select the most compatible relatives of patients to be transplant donors. In 1968, Bach used the technique to select donors for the first successful clinical bone marrow transplants; these were carried out in parallel at the Universities of Minnesota and Wisconsin respectively. Dr Robert A. Good saved the life of a five-month-old boy, born with a bone marrow defect, then Bach and his team operated on a two-year-old boy who bled constantly and suffered repeated infections. In both cases, bone marrow from a sister was used for the transplant.
Bach continually honed this process, expanding it from bone marrow to other body parts and greatly speeding up the technique. By 1975, he had developed a way to complete his analysis in hours, rather than days. This greatly benefitted the transplant of cadaver kidneys which need to be used within 48 hours before decomposing. Bach's test led to further research on how the human immune system responds to the Major Histocompatibility Complex, a system of surface proteins on cells that define each person's unique immunity.
Other research interests included transplanting pig tissues (xenotransplantation) into humans; however, in 1998 Bach became the public voice of caution, urging the scientific community to include the public in decisions about the use of animal cells and organs in humans. Disturbed by the possible ramifications of such work, which could include the introduction of serious diseases to humanity, he called for a moratorium on using pig cells and organs to treat people until a public commission could be created to gauge the dangers.
Born into a Jewish family in Vienna, Austria on 5 April 1934, Fritz Heinz Bach was the younger of two brothers. Following the Nazi pogrom, known as Kristallnacht (Night of Broken Glass), against Jews, their homes and businesses throughout Nazi Germany and Austria between 9 and 10 November 1938, Bach and his brother fled to England through the Kindertransport, a rescue mission that helped 10,000, predominantly Jewish children, be repatriated in British families. Though the boys were later reunited with their parents in Bath, their grandparents perished in the Holocaust.
In 1948, sponsored by an American GI, the family immigrated to the US and settled on the east coast in Vermont. Bach won a scholarship to Harvard, where he graduated with a degree in physical science in 1955, before moving on to study medicine at Washington University. In 1960, he completed his M.D. at Harvard Medical School, Boston, where he became interested in immunology and genetics. After post-doctoral studies, Bach lectured at the University of Wisconsin and led a research team from 1965 to 1980. Thereafter, he taught and conducted research at the University of Minnesota before returning to Harvard to teach in 1990. From 2001, Bach was appointed the Lewis Thomas Distinguished Professor at Harvard Medical School.
Bach, a prolific writer, published more than 800 scientific papers and received numerous national and international awards, including the Established Investigator Award from the American Heart Association. In 2005, Bach's life turned full-circle when he returned to Austria to receive an honorary degree, Honoris Causa, from the University of Vienna.
Bach died after a heart attack at his home in Manchester-by-the-Sea, Massachusetts, aged 77. He is survived by his two wives, Marilyn Lee Brenner and Jeanne Elizabeth Gose, both marriages ending in divorce, and their five children and four grandchildren.
Fritz Bach, doctor/scientist: born Vienna, Austria 5 April 1934; married 1958 Marilyn Lee Brenner (two children), 1983 Jeanne Elizabeth Gose (three children); died Manchester-by-the-Sea, Massachusetts 19 August 2011.