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Leslie Brent and the mysterious German surgeon.

In a 3 and a half page article in the October 3, 1953, issue of Nature,1 and more extensively in 1956 in the Philosophical Transactions of the Royal Society of London,2 Billingham, Brent, and Medawar reported the successful transplantation in mice of the immune cells (leukocytes) that make up the normal bone marrow, spleen, and lymph nodes. The donor cells were obtained from adult mice and infused intravenously into unaltered newborn mouse recipients whose immune system was not yet sufficiently developed to reject the cells. When the recipient mice grew up, they could freely accept skin and other tissues from the original cell donor, but from no other donor. These world's first examples of acquired transplantation tolerance led to Medawar's corecipiency (with F. Macfarlane Burnet) of the 1960 Nobel Prize. Medawar shared his portion of the cash award with Billingham and Brent. 
 
The sobriquet “holy trinity” was applied to Billingham, Brent, and Medawar when their 1953 observations escalated during the next 15 years to clinical bone marrow and organ transplantation. Peter Brian Medawar, the senior author of their seminal paper, was a 38-year-old zoologist, who in World War II-related duties had demonstrated a dozen years earlier that the barrier to successful transplantation is a donor-specific immune response.3 The rank order of authorship in all publications by Medawar's research group was determined alphabetically. Accordingly, the lead author of the 1953 Nature article was 32-year-old Rupert Billingham, who had spent the war as a lieutenant on antisubmarine escort vessels. Five years after completing their famous 3-author paper, Billingham moved to the Wistar Institute in Philadelphia and developed a fruitful collaboration with the future University of Pennsylvania surgery chairman, Clyde Barker, before moving to the University of Texas (Dallas) as Chairman of the Department of Cell Biology and Anatomy. Medawar died in 1987 (at 71 years) and Billingham in 2002 (81 years). 
 
The third author, Leslie Brent, was the youngest. Brent was born on July 25, 1925 (his birth name was Lothar Baruch) in Koslin, a small German market town that is now a thriving Polish city of 110,000 (spelled Koszalin). Because of being persecuted in the predominantly non-Jewish local schools, his family placed him in a Jewish orphanage in Berlin in 1936 (Fig. 1); his parents and sister moved to Berlin the following year. After the Kristallnacht pogrom of November 8–10, 1938 (“the night of broken glass”), the young Brent escaped to England in the Kindertransport operation that saved 10,000 Jewish children from extermination. Neither his parents nor anyone else in his immediate family survived the Holocaust. After a stint in the British infantry between ages 18 and 22 (1943–1947, final rank captain; Fig. 2), he became Medawar's student and later his associate (Fig. 3). In 1969, he was appointed Professor of Immunology at St. Mary's Hospital and Medical School, London, a position held with distinction until his retirement in 1990 (Fig. 4). 
 
 
 
FIGURE 1. Leslie Baruch at the age of 10, before entry into the Jewish orphanage in Berlin. 
 
 
 
 
 
FIGURE 2. Leslie Brent, the 21-year-old infantry officer whose adopted name was registered in England as an antigenocide precaution in the event of capture. 
 
 
 
 
 
FIGURE 3. Leslie Brent approximately 40 years old, with his scientific mentor/colleague, Peter Medawar. 
 
 
 
 
 
FIGURE 4. Leslie Baruch Brent in his 80th year (photo by Z. Pacholski Liszalin, Poland). The birth name, Baruch, was officially restored (as Brent's middle name) in the late 1990s. 
 
 
 
Brent made no secret of his early difficult life, but it was not a subject upon which he cared to dwell. Recently, he authorized me to make public my correspondence with him that took place during 1996–1997, along with my related correspondence with 2 distinguished German surgeons. One of the surgeons was Rudolf Pichlmayr, Dhc, MD, Professor and Chairman, Department and Clinics of Abdominal and Transplantation Surgery, Hannover University Medical School. An Honorary Fellow of the Royal College of Surgeons (Eng) and of the American College of Surgeons, Pichlmayr was the principal speaker at the transplantation session of the World Congress of Surgery in Acapulco, Mexico, on August 29, 1997. During an early morning swim, he apparently was caught in an undertow and drowned. He had just turned 65 years old and was deeply mourned throughout Germany and the world. 
 
The other surgeon was Michael Trede, BA, MD, BChir, Professor and Chairman of the Mannheim Surgical Clinics and University of Heidelberg Medical School. Trede was a major figure after World War II in restoring Germany's place in international surgery. He is an Honorary Fellow of all 4 British Royal Surgical Colleges; an honorary member of the American Surgical Association and American College of Surgeons; and coeditor Emeritus of the World Journal of Surgery. Trede recently published a German-language autobiography4 in which the same events are described as in the following self-explanatory letters.