Robert J. Corry

Primarily vascularized allografts of hearts in mice. The role of H-2D, H-2K, and non-H-2 antigens in rejection.

Mouse hearts were transplanted heterotopically as primarily vascularized grafts. Donors and recipients were selected to provide combinations in which there was histoincompatibility with respect to antigens whose specificities are determined by genes at the H-2D region only (B10.BR → B6AF1), at the H-2K region only (B10.D2 → B6AF1), at loci other than H-2 (129 → B/10); and at H-2D, H-2K, and non-H-2 loci (A → (129 X B/10)F1). In all of these combinations there were acute episodes of rejection as indicated by sharp declines in palpable impulse. Return of cardiac impulse was commonly observed after this initial decline but was short lived except in the case of B10.BR grafts in B6AF1 hosts. In that combination all of the grafted hearts showed at least partial recovery and long-term survival. Hearts appear to be more vulnerable than kidneys but less vulnerable than skin to allograft reactions. In the combinationss studied there was a close relationship between the survival times of allografts of hearts and skin. Both types of grafts underwent relatively early and acute rejection in situations involving only non-H-2 differences and they had similar degrees of prolongation in survival time when placed on mice treated with antiserum specifically reactive with graft antigens. Differential survival of allografts of various kinds is ascribed to both differences in the intensity of the immune responses that are provoked and differences in sensitivity to attack by immune substances.

Tolerogenic immunosuppression for organ transplantation

BACKGROUND Insight into the mechanisms of organ engraftment and acquired tolerance has made it possible to facilitate these mechanisms, by tailoring the timing and dosage of immunosuppression in accordance with two therapeutic principles: recipient pretreatment, and minimum use of post-transplant immunosuppression. We aimed to apply these principles in recipients of renal and extrarenal organ transplants. METHODS 82 patients awaiting kidney, liver, pancreas, or intestinal transplantation were pretreated with about 5 mg/kg of a broadly reacting rabbit antithymocyte globulin during several hours. Post-transplant immunosuppression was restricted to tacrolimus unless additional drugs were needed to treat breakthrough rejection. After 4 months, patients on tacrolimus monotherapy were considered for dose-spacing to every other day or longer intervals. FINDINGS We frequently saw evidence of immune activation in graft biopsy samples, but unless this was associated with graft dysfunction or serious immune destruction, treatment usually was not intensified. Immunosuppression-related morbidity was virtually eliminated. 78 (95%) of 82 patients survived at 1 year and at 13-18 months. Graft survival was 73 (89%) of 82 at 1 year and 72 (88%) of 82 at 13-18 months. Of the 72 recipients with surviving grafts, 43 are on spaced doses of tacrolimus monotherapy: every other day (n=6), three times per week (11), twice per week (15), or once per week (11). INTERPRETATION The striking ability to wean immunosuppression in these recipients indicates variable induction of tolerance. The simple therapeutic principles are neither drug-specific nor organ-specific. Systematic application of these principles should allow improvements in quality of life and long-term survival after organ transplantation.

Oxygen free radical induced damage in kidneys subjected to warm ischemia and reperfusion. Protective effect of superoxide dismutase.

Superoxide anion free radical (O2-.) has been implicated in the pathogenesis of tissue injury consequent to ischemia/reperfusion in several different organs, including heart and bowel. Superoxide dismutase (SOD), an enzyme free radical scavenger specific for O2-., has been used successfully to protect these organs from structural damage during reoxygenation of ischemic tissue. It has been suggested that the catalytic action of xanthine oxidase in injured tissue is an important source of O2-. during reoxygenation. In order to evaluate the potential of SOD to protect against kidney damage resulting from transient ischemia followed by reperfusion with oxygenated blood, a model of warm renal ischemia was studied. LBNF1 rats underwent right nephrectomy and occlusion of the left renal artery for 45 minutes. Survival in the group of ischemic untreated rats (N = 30) was 56% at 7 days and serum creatinine was greatly elevated (p less than 0.01) in rats remaining alive over the full 7-day period. In strong contrast to these results, all of the animals treated with SOD before reperfusion (N = 18) were alive after 7 days similar to sham operated control rats (N = 8). Serum creatinine in the SOD treated rats was significantly elevated only to postoperative day 3 and thereafter returned to normal. Rats treated with inactive SOD (N = 4) or SOD before ischemia (N = 4) had decreased survival rates compared to ischemic untreated animals and prolonged elevation of serum creatinine. When the ischemia time was extended to 60 minutes, only 19% of the untreated animals (N = 16) survived at 7 days whereas nearly 60% of the SOD-treated animals survived (N = 19). Serum creatinine was greatly elevated during the full 7-day observation period in all surviving rats in the untreated ischemic group, whereas serum creatinine returned to normal (p less than 0.05) after 4 days in the surviving rats treated with SOD. To test whether the action of xanthine oxidase contributed to the kidney damage after reoxygenation, 45 min. ischemic rat kidneys were treated with allopurinol. All of the animals treated with allopurinol (N = 12) were alive at 7 days. Serum creatinine values returned to normal after the episode of ischemia and reperfusion but more slowly than after SOD treatment. Histologic evaluation of kidney tissue taken from animals after ischemia alone showed extensive renal tubular damage, which was essentially absent in kidneys from SOD-treated animals.(ABSTRACT TRUNCATED AT 400 WORDS)

Increased frequency of posttransplant lymphomas in patients treated with cyclosporine, azathioprine, and prednisone

We have documented seven B cell lymphomas over a six-month period in 132 (5.3%) kidney and heart allograft recipients immunosuppressed with cyclosporine, azathioprine, and prednisone (triple therapy). This is a significant increase (P less than 0.0001) over the number of such tumors seen by us previously. Only 2 lymphomas had occurred in 669 cadaver and 29 living-related kidney allografts treated with azathioprine and prednisone alone (0.3%). In 160 cadaver kidney recipients treated with cyclosporine and prednisone there have been no lymphomas. Similarly in 14 living-related kidney recipients who were transplanted since the introduction of triple therapy for cadaver grafts, but continued to receive only azathioprine and prednisone, no lymphomas occurred. There seemed to be a clear relationship between this increase and the use of triple therapy. This led us to examine other possible contributing factors. A case control study has not shown any other factor that differs in patients in whom lymphomas developed. We have only been able to demonstrate Epstein Barr virus nuclear antigen in the cells of one tumor. Four of these 7 tumors were monoclonal, one polyclonal, and two indeterminate. All patients had their immunosuppression withdrawn and six received intravenous acyclovir. Three patients have shown some response but four patients died. Triple therapy is being used by many centers to reduce the level of cyclosporine toxicity. We wish to sound a note of caution that this may result in an increased incidence of posttransplant lymphomas.

Logistics and Technique for Procurement of Intestinal, Pancreatic, and Hepatic Grafts From the Same Donor

ObjectiveTo assess a technique for simultaneous recovery of the intestine, pancreas, and liver from the same donor. Summary Background DataWith the more frequent use of pancreatic and intestinal transplantation, a procurement procedure is needed that permits retrieval of both organs as well as the liver from the same cadaveric donor for transplantation to different recipients. It is believed by many procurement officers and surgeons, however, that this objective is not technically feasible. MethodsA technique for simultaneous recovery of the intestine, pancreas, and liver was used in 13 multiorgan cadaver donors during a 26-month period, with transplantation of the organs to 33 recipients. The intestine was removed from 11 donors separately and in continuity with the pancreas in the other 2. Six additional pancreases were excised and transplanted separately. Thirteen livers were retrieved, one of which was discarded because of steahorrhea. Ten of the remaining 12 livers were transplanted intact; the other 2 were split in situ and used as reduced-size hepatic allografts in four recipients. ResultsNone of the 11 intestinal, 6 pancreatic, 2 intestinal–pancreatic, or 14 whole or partial liver allografts sustained serious ischemic injury or were lost as a result of technical complications. One liver recipient died 25 months after surgery of recurrent C virus hepatitis. The other 32 recipients had adequate allograft function with a mean follow-up of 8 months. ConclusionIt was possible using the described technique to retrieve intestine, pancreas, and liver allografts safely from the same donor and to transplant these organs to different recipients.

Technique of simultaneous renal pancreatoduodenal transplantation with urinary drainage of pancreatic secretion

There are many advantages to transplanting the pancreas in the right iliac fossa and draining the pancreatic exocrine secretions into the bladder. This technique has been performed successfully in nine patients and the details have been discussed herein.

An Analysis of Early Renal Transplant Protocol Biopsies - the High Incidence of Subclinical Tubulitis

To investigate the possibility that we have been underestimating the true incidence of acute rejection, we began to perform protocol biopsies after kidney transplantation. This analysis looks at the one‐week biopsies. Between March 1 and October 1, 1999, 100 adult patients undergoing cadaveric kidney or kidney/pancreas transplantation, or living donor kidney transplantation, underwent 277 biopsies. We focused on the subset of biopsies in patients without delayed graft function (DGF) and with stable or improving renal function, who underwent a biopsy 8.2 ± 2.6 d (range 3–18 d) after transplantation (n = 28). Six (21%) patients with no DGF and with stable or improving renal function had borderline histopathology, and 7 (25%) had acute tubulitis on the one‐week biopsy. Of the 277 kidney biopsies, there was one (0.4%) serious hemorrhagic complication, in a patient receiving low molecular weight heparin; she ultimately recovered and has normal renal function. Her biopsy showed Banff 1B tubulitis. In patients with stable or improving renal allograft function early after transplantation, subclinical tubulitis may be present in a substantial number of patients. This suggests that the true incidence of rejection may be higher than is clinically appreciated.

Results of pancreas transplantation after steroid withdrawal under tacrolimus immunosuppression

PURPOSE The results of steroid withdrawal in pancreas transplant recipients under tacrolimus immunosuppression were analyzed. METHODS From July 4, 1994 until April 30, 1998, 147 pancreas transplantations were performed in 141 patients, including 126 simultaneous pancreas-kidney transplantations, 13 pancreas after kidney transplantation, and 8 pancreas transplantations alone. Baseline immunosuppression consisted of tacrolimus and steroids without antilymphocyte induction. Twenty-three patients were excluded from analysis because of early graft loss in 17 cases, retransplantation in 5 cases, and simultaneous pancreas-kidney transplantation after heart transplantation in 1 patient. RESULTS With a mean follow-up of 2.8+/-1.1 years (range 1.0 to 4.8 years), complete steroid withdrawal was achieved in 58 (47%) patients with a mean time to steroid withdrawal of 15.2+/-8 months (range 4 to 40 months after transplantation). Of the entire cohort of 141 patients, overall 1-, 2-, and 4-year patient survival rates were 98%, 95.5%, and 86%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 83%, 80%, and 71% (pancreas) and 95%, 91%, and 84% (kidney), respectively. Of the 124 patients analyzed for steroid withdrawal, 1-, 2-, and 4-year patient survival rates were 98%, 97%, and 92%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 98%, 91.5%, 83% (pancreas) and 97%, 95%, and 91% (kidney). Patient, pancreas, and kidney survival rates at 1 year were 100%, 100%, and 98% (off steroids) versus 97%, 91%, and 96% (on steroids, all NS) and at 4 years were 100%, 94%, and 95% (off steroids) versus 78%, 68%, and 85% (on steroids, P = 0.01, 0.002, and NS, respectively). The cumulative risk of rejection at the time of follow-up was 76% for patients on steroids versus 74% for patients off steroids (P = NS). Seven patients originally tapered off steroids were treated for subsequent rejection episodes, which were all steroid sensitive, and two of these seven patients are currently off steroids. Thirteen patients received antilymphocyte therapy for steroid-resistant rejection, five of whom are now off steroids. Tacrolimus trough levels were 9.3+/-2.4 ng/ml (off steroids) and 9.7+/-4.3 (on steroids, P = NS). Mean fasting glucose levels were 98+/-34 mg/dl (off steroids) and 110+/-41 mg/dl (on steroids, P = NS). Mean glycosylated hemoglobin levels were 5.2+/-0.9% (off steroids) and 6.2+/-2.1% (on steroids, P = 0.02), and mean serum creatinine levels were 1.4+/-0.8 mg/dl (off steroids) and 1.7+/-1.0 mg/dl (on steroids, P = 0.02). CONCLUSION These data show for the first time that steroid withdrawal can be safely accomplished in pancreas transplant recipients maintained on tacrolimus-based immunosuppression. Steroid withdrawal is associated with excellent patient and graft survival with no increase in the cumulative risk of rejection.

LONG-TERM RESULTS OF PANCREAS TRANSPLANTATION UNDER TACROLIMUS IMMUNOSUPPRESSION

Background The long-term safety and efficacy of tacrolimus in pancreas transplantation has not yet been demonstrated. The observation of prolonged pancreatic graft function under tacrolimus would indicate that any potential islet toxicity is short-lived and clinically insignificant. We report herein the results of pancreas transplantation in patients receiving primary tacrolimus immunosuppression for a minimum of 2 years. Methods. From July 4, 1994 until April 18, 1996, 60 patients received either simultaneous pancreas-kidney transplant (n=55), pancreas transplant only (n=4), or pancreas after kidney transplantation (n=1). Baseline immunosuppression consisted of tacrolimus and steroids without antilymphocyte induction. Azathioprine was used as a third agent in 51 patients and mycophenolate mofetil in 9. Rejection episodes within the first 6 months occurred in 48 (80%) patients and were treated with high-dose corticosteroids. Antilymphocyte antibody was required in eight (13%) patients with steroid-resistant rejection. Results. With a mean follow-up of 35.1±5.9 months (range: 24.3-45.7 months), 6-month and 1-, 2-, and 33-year graft survival is 88%, 82%, 80%, and 80% (pancreas) and 98%, 96%, 93%, and 91% (kidney), respectively. Six-month and 1-, 2-, and 3-year patient survival is 100%, 98%, 98%, and 96.5%. Mean fasting glucose is 91.6±13.8 mg/dl, and mean glycosylated hemoglobin is 5.1±0.7% (normal range: 4.3-6.1%). Mean tacrolimus dose is 6.5±2.6 mg/day and mean prednisone dose 2.0±2.9 mg/day at follow-up. Complete steroid withdrawal was possible in 31 (65%) of the 48 patients with functioning pancreases. Conclusions. These data show for the first time that tacrolimus is a safe and effective long-term primary agent in pancreas transplantation and provides excellent long-term islet function without evidence of toxicity while permitting steroid withdrawal in the majority of patients.

Combined simultaneous kidney/bone marrow transplantation.

On the basis of observations in patients with long-term (28-30 years) renal allograft survival, all of whom had evidence of systemic microchimerism, we began a program of combined simultaneous kidney/bone marrow transplantation. Between 12/14/92, and 10/31/94, 36 kidney transplant recipients received 3-5 x 10(8) unmodified bone marrow cells/kg; 6 patients also received pancreatic islets, and 7 patients also received a pancreas. The mean recipient age was 39.0 +/- 10.8 years, and the mean donor age was 31.8 +/- 16.1 years; the mean cold ischemia time was 23.0 +/- 9.1 hr. Twenty control patients received kidneys alone, mainly because of refusal by the donor family to consent to vertebral body recovery; 3 of these patients also received a pancreas. The mean recipient age was 47.9 +/- 11.7 years, and the mean donor age was 41.5 +/- 17.9 years; the mean cold ischemia time was 28.6 +/- 6.2 hr. All patients received tacrolimus-based therapy, without radiation, cytoreduction, or induction antilymphocyte preparations. Blood was drawn prior to and at regular intervals after transplantation for detection of chimerism and for immunologic studies. With a mean follow-up of 11.1 +/- 5.8 months, all 36 study patients are alive, and 33 (92%) have functioning allografts with a mean serum creatinine of 1.9 +/- 1.2 mg/dl and a BUN of 26 +/- 9 mg/dl. Graft vs. host disease was not seen in any patient. The incidence of rejection was 72%; 11% of the patients required OKT3 or ATG for steroid-resistant rejection. The incidence of CMV was 14%, and that of delayed graft function was 17%. A total of 18 (90%) control patients are alive, and 17 (85%) have functioning allografts, with a mean serum creatinine of 2.1 +/- 1.3 mg/dl, and a BUN of 30 +/- 13 mg/dl. The incidence of rejection was 60%, and 10% required OKT3 or ATG. CMV was seen in 15%, and delayed graft function in 20% (P = NS). In the study patients, chimerism was detected in the peripheral blood of 30 of 31 (97%) evaluable patients by either PCR or flow cytometry. In the control patients, chimerism was seen in 9 of 14 (64%) evaluable patients (P < .02). Decreasing donor-specific responsiveness was seen in 6/29 (21%) evaluable study, and 4/14 (29%) evaluable control patients (P = NS). We conclude that combined kidney/bone marrow transplantation is associated with acceptable patient and graft survival, augmentation of chimerism, and no change in the early events after transplantation.