Lasker~DeBakey Clinical award ESSAY

“It can’t be done”

Roy Y Calne

In 1950, medical students in the UK were working at the Royal College of Surgeons in early 1960s using independently developed allocated patients for whom we had a special, England, I found that total-body X-ray irradia- blood bypass procedures. personal responsibility and acted as advocate. tion failed to prolong kidney survival, but I presented the case of a patient about my age the antileukemia drug 6-mercaptopurine pro- The move to the clinic dying of kidney failure. The senior consultant longed renal allograft survival in dogs. Sir Peter The move of transplantation to the clinic told me to make my patient as comfortable as Medawar felt this observation to be worthy of was pioneered in 1963 by Thomas Starzl5, but possible, but, sadly, he would be dead in two intense and prolonged study, and this proved the results of the first pilot study were disas- weeks. I was appalled by this stark prognosis to be the case3, as it led to the introduction of trous, and he decided on a moratorium while and, thinking in terms of gardening, I asked azathioprine, the first effective clinical immu- further experimental work was performed. In whether the patient could receive a kidney nosuppressant. the clinic, only patients desperately ill were graft. The consultant said no, and, when I asked I was fortunate to receive a Harkness referred for consideration of this untried opera- why not, I was told “it can’t be done.” I was per- Fellowship to study at Harvard Medical School tion, and it is not surprising that some of these plexed because it seemed that there were only in Francis Moore’s Department of Surgery, patients were unfit for an anesthetic, let alone a three plumbing junctions required—an artery, where Moore himself was pioneering the tech- liver transplant. The anesthesia and the inten- a vein and the ureter—and surgical techniques nique of in dogs at the sive care after the operation required compli- were available to accomplish these tasks. I had same time that Thomas Starzl was doing similar cated physiological considerations and special no idea of the phenomenon of graft rejection. experiments in Denver. I was therefore exposed training for anesthetists and nurses, so that care I returned to the subject in 1959 after hear- to the formidable technical obstacles to be over- of the patient after the operation by both sur- ing give a lecture in Oxford come, but my work in Moore’s department was gical and hepatological teams remained at the explaining the immunological nature of graft concentrated on and on same level of vigilance as during the surgical rejection and the exciting experiments that he developing drugs given to me by the Nobel lau- procedure (Fig. 1). Also essential was an in- and his colleagues had done, showing “specific reates George Hitchings and Gertrude Elion, depth understanding of the immunosuppres- immunological tolerance”1. The concept of the who had synthesized 6-mercaptopurine. They sive drugs, none of which was perfect, having developing immune system in the fetus, which suggested that I study a series of compounds, toxic side effects. would accept as a ‘self-product’ any potential and one of them, azathioprine, turned out to be Our own interest in liver transplantation fol- antigen with which it came in contact, raised an a little better than 6-mercaptopurine in terms lowed studies on the of liver trans- important question not yet answered: could an of promoting graft survival4. Azathioprine plants and the unexpected acceptance of liver adult immune system be temporarily returned was used in clinical grafts that was observed between unrelated pigs to the fetal state while the organ graft was with results that were sometimes encouraging without any treat- inserted, and could the immune system then despite there being many failures. On return- ment. Usually, typical features of rejection were regain its protective role, having accepted the ing to the UK in 1961, I continued with this observed but they resolved spontaneously6, an foreign graft? work and was appointed the Chair of Surgery interesting and previously little studied phe- at Cambridge University in 1965. nomenon that presumably had similarities to Hurdles to transplantation Transplantation of the liver is a formidable the immune reactions that occur after a virus Since 1959, my professional work has been operation, and for those attempting the pro- infection, when the powerful antibody and cell- focused on , and from cedure for the first time, when there was no mediated immunities are switched off after the the beginning it was clear that there were two previous experience, mistakes were made at infection has been defeated. separate series of problems to overcome. The every stage. But gradually a corpus of knowl- Although pigs have been bred over hundreds first was technical and, for the kidney, this was edge developed, and errors were recognized and of years to improve the quality of their meat, solved by with the successful subsequently avoided. Even in a healthy animal they are in no sense inbred, as are laboratory transplant of a kidney between identical twins2. recipient the orthotropic operation is of great murine strains. The porcine liver graft could also The second was immunological: the biological magnitude, involving removal of the recipient protect other tissues such as kidney and skin rejection of transplanted tissue. In 1959, while liver and thereby totally blocking the return of from the same donor from being rejected. These blood from the inferior vena cava and the intes- observations were supplemented by many stud- Roy Y. Calne is Emeritus Professor of Surgery, tinal portal system to the heart. The physiologi- ies in inbred rats, and it was shown that, between University of Cambridge, Cambridge, UK. cal disturbances were overcome experimentally certain strains, irreversible rejection occurred e-mail: [email protected] by both Starzl and Moore in the late 1950s and and, between others, there was little evidence

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disease and malignancies were the laboratory and first used in clinical organ regarded as too ill to continue transplantation in Cambridge12. Cyclosporin immunosuppression, which improved the one-year kidney graft survival was deliberately stopped. from around 50% to more than 80%. This Some of these patients did not was seized upon by some of those who had reject their liver grafts, others previously been critical of the whole idea of did. The procedure of weaning transplantation, and they became enthusiastic from immunosuppression was supporters and performers of the procedure. investigated extensively in the Prior to the advent of cyclosporine, there Denver/ series9. It were about ten centers seriously performing became apparent that opera- organ transplantation in the world; within a tional tolerance in some cases few years of its introduction there were more was extremely robust, with than 1,000, and the new problem of shortage of patients maintaining good organ donors started to become apparent and function in their grafts for has become increasingly worrisome ever since. many years, whereas in other The introduction of cyclosporine into the cases the tolerance was more clinic improved the results of liver transplan- fragile, and rejection could tation. Another valuable immunosuppressive be precipitated by extraneous drug, FK506, or , was discovered factors, for example, infection. in Japan and brought to the clinic by Starzl Two factors were, in fact, in Pittsburgh. Tacrolimus is a calcineurin known. First, the liver is a inhibitor with a mode of action similar to major source of soluble human cyclosporine. Another powerful immunosup- leukocyte antigen (HLA) class I pressant with a different mode of action and antigen which can have a toxicity profile, rapamycin, was developed in specific immunosuppressive Cambridge13. effect, and approximately half When new immunosuppressive agents of circulating HLA class 1 anti- became available there was a tendency for cli- gen in the blood of recipients of nicians to add them to previous protocols. This liver transplants is produced by often led to severe toxicity, excessive immuno- Figure 1 R.Y. Calne, The Liver Transplant Patient and The Tribute the donor organ. Second, there suppression, infection and a deterioration of to the Compassion and Skill of the Intensive Care Nurse. Oil on is well-recorded trafficking of clinical results. Our observation of liver toler- canvas, 4 × 3 ft. Commissioned by Goran Klintmalm of the Liver cells between the liver graft ance in the pig with the spontaneous resolution Institute in Dallas. and recipient, particularly of of immunological rejection suggested to us that passenger leukocytes and espe- any approach toward achieving the goal of of rejection. Some rat liver transplants behaved cially Kupffer cells, and it has been suggested immunological tolerance would require active in a manner similar to those in pigs, with rejec- that these play an important part in the relative engagement of the immune system of the recip- tion and then spontaneous recovery. Reports of lack of rejection of liver allografts, producing ient with donor tissue. Excessive immunosup- these experiments provoked the Lancet to write ‘microchimerism’, which may have a specific pression might prevent this engagement and a leading article entitled “Strange English Pigs”7. immunosuppressive effect10. prevent tolerance. We hypothesized that a win- However, the phenomenon was not limited to Despite the failure to provide a complete dow of opportunity for immunological engage- the origin of the pigs and was repeated in other picture to explain the phenomenon, the obser- ment, or ‘WOFIE’, might be an essential step in laboratories8. vations above confirmed the immunologically the development of tolerance; so, in the clinic, In the clinic, the hurdle of performing liver privileged status of the liver transplant experi- efforts should be made to use immunosuppres- transplant in an exceedingly sick patient was mentally and in the clinic. sion at the lowest level that would permit graft difficult to overcome, and there were many In 1967, Starzl recommenced liver trans- acceptance. The pendulum has now swung failures. But when success was achieved, pre- plantation. Shortly after that, I performed the toward minimalization of immunosuppres- vention of rejection seemed to be easier to first liver transplant in Europe in 1968. I was sion, and we have been particularly impressed accomplish than in cases of kidney and heart given strong scientific support by Moore, who with the use of the powerful antilymphocyte transplantation. In the largest clinical series happened to be visiting Cambridge and who monoclonal antibody Campath-1H, devel- in Denver, some of the patients initiated an also scrubbed in at the operation as my first oped by Waldmann’s group in Cambridge, important experiment without telling their assistant, something for which I was extremely given as an induction treatment followed by doctors and deliberately stopped taking immu- grateful11. This was the beginning of our pro- a low-maintenance immunosuppression regi- nosuppressive drugs because they disliked the gram of liver transplantation in Cambridge, men. It has been slow to be adopted, but this side effects. This noncompliance is a common which linked up with Roger Williams’s hepatol- so-called “prope”14 or almost-tolerance has phenomenon in recipients of all grafts, par- ogy unit in King’s College Hospital in London. resulted in excellent quality of life for most ticularly teenagers and especially girls. Years patients; more than 80% of our patients had later, these patients, who had become ‘opera- Immunosuppression never had steroid treatment at any stage (ste- tionally tolerant’, were studied and seemed to An important watershed moment in the roids, used extensively as immunosuppressive have accepted their without serious pen- management of all organ transplants was the maintenance drugs, can have unpleasant and alties. Coincidentally, some patients with viral introduction of cyclosporine, developed in dangerous side effects)15.

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being abducted and their organs removed by criminal gangs, leaving the unwilling donor without a kidney or even dead. There have also been questions raised as to whether all patients who might benefit from an organ deserve to get a graft, for example, those suffering from alco- holic disease or self-induced drug abuse. There have been serious concerns regarding the qual- ity of the organs that are offered, as well as about the age and health of the donor and recipient. The transplant community is rightly con- cerned with these ethical matters, and even if they cannot all be overcome, defining and dis- cussing the moral dilemmas that may arise in organ transplantation is a move toward improv- ing the ethical background in which transplants are performed. Organ transplants have intro- duced new ethical worries for the community, but the organ donor—whether a live volunteer or a donor after death—is the true hero of organ transplantation (Fig. 2).

COMPETING FINANCIAL INTERESTS The author declares no competing financial interests. Figure 2 R.Y. Calne, Tribute to the Organ Donor—The Real Hero of Transplantation, 2000. Bronze, approximately 18 in. One of a series of 12 castings. 1. Billingham, R.E., Brent, L. & Medawar, P.B. Actively acquired tolerance of foreign cells. Nature 172, 603– 606 (1953). Ethical issues has precipitated worrying ethical matters, since 2. Murray, J.E., Merrill, J.P. & Harrison, J.H. Renal The shortage of organ donors has put enormous removal of half a liver from an adult is a major homotransplantation in identical twins. Surg. Forum 6, 432–436 (1955). pressure on health resources by patients and procedure with a significant morbidity and 3. Calne, R.Y. The rejection of renal homografts. Inhibition doctors. The introduction of a new and suc- mortality. In one report, for example, five liver in dogs by using 6-mercaptopurine. Lancet 275, 417– cessful treatment may be regarded as a therapy 16 418 (1960). donors themselves developed liver failure . 4. Calne, R.Y. Inhibition of the rejection of renal homo- that should be available for all in need, but this Four died and one was successfully treated by grafts in dogs by purine analogues. Transplant. Bull. is impossible for organ transplants. Fostering becoming a liver transplant recipient. 28, 65–81 (1961). 5. Starzl, T.E. et al. Homotransplantation of the liver in the culture of charity and compassion in organ So, organ transplantation has led to an humans. Surg. Gynecol. Obstet. 117, 659–676 (1963). donation is probably the most important unprecedented break with traditional medical 6. Calne, R.Y. et al. Induction of immunological toler- approach to improving the number of organ ethics, in that under certain carefully defined ance by porcine liver allografts. Nature 223, 472–476 (1969). transplants. conditions a normal healthy individual may be 7. Anonymous. Strange english pigs. Lancet 294, 940– In Spain, the development of an outstand- harmed. Within a family, for a parent to donate 941 (1969). ingly successful cadaveric pro- a kidney or part of a liver to a child is not dis- 8. Benseler, V. et al. The liver: a special case in trans- plantation tolerance. Semin. Liver Dis. 27, 194–213 gram has been admired and emulated by some puted, and this acceptance is usually extended (2007). countries. It involves an ‘opt-out’ law on organ to sibling-to-sibling donation and donation 9. Mazariegos, G.V. et al. Risks and benefits of wean- donation and the presence of medically quali- from other family members, including spouses. ing immunosuppression in liver transplant recipients: long-term follow-up. Transplant. Proc. 29, 1174–1177 fied coordinators in all hospitals in Spain. There is, however, a danger in any operation, (1997). An opt-out law does seem to confer advan- and not only liver but even kidney donors have 10. Starzl, T.E. et al. Cell migration, chimerism and graft acceptance. Lancet 339, 1579–1582 (1992). tages, as it permits the removal of organs after died. With liver donors, the risks are much 11. Calne, R.Y. et al. Cyclosporin A initially as the only death provided no objection has been made by greater, especially in adult-to-adult donation, immunosuppressant in 34 recipients of cadaveric the patient in his or her lifetime and that the and the concept of informed consent can be organs: 32 kidneys, 2 pancreases, and 2 livers. Lancet 314, 1033–1036 (1979). views of grieving relatives are not over-ridden. difficult to grasp for all concerned. 12. Calne, R.Y. & Williams, R. Liver transplantation in In Singapore, the introduction of an opt-out law The gift of an organ is really a ‘gift of life’, and man. Observations on technique and organization in was followed by a tenfold increase in the num- something as valuable as a life-saving organ is five cases. BMJ 4, 535–540 (1968). 13. Calne, R.Y. et al. Rapamycin for immunosuppression ber of deceased organ donations. far more important to a suffering patient than in organ allografting. Lancet 334, 227 (1989). However, in most countries, it is not possible wealth or power. To obtain an organ when a 14. Calne, R.Y. et al. H. Prope tolerance, perioperative cam- path IH, and low-dose cyclosporin monotherapy in renal to obtain enough cadaveric organ donors, and donor is not available puts stress on moral val- allograft recipients. Lancet 351, 1701–1702 (1998). living donors for liver grafting have been used, ues. A rich person may travel to a poor coun- 15. Calne, R.Y. & Watson, C.J.E. Some observations on especially in Japan from parents to children. try to pay for an organ from an impoverished prope tolerance. Curr. Opin. Organ Transplant. 16, 353–358 (2011). Gradually, the indications have been widened donor or from a criminal subjected to capital 16. Ringe, B. et al. Rescue of a living donor with liver trans- to adult-to-adult liver grafting, something that punishment. There have been cases of people plantation. Am. J. Transplant. 8, 1557–1561 (2008).

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