S. Takaya

Liver, kidney, and thoracic organ transplantation under FK 506

The new immunosuppressive drug FK 506 was used from the outset with low doses of prednisone to treat 120 recipients of primary liver grafts and 20 more patients undergoing liver retransplantation. The patient survival rate after 2 to 8 months in the primary liver transplantation series is 93.3%, with original graft survival of 87.5%. Of the 20 patients in the hepatic retransplant series, 17 (85%) are living. Almost all of the surviving patients have good liver function. In addition 11 hearts, 2 double lungs, and a heart-lung have been transplanted under FK 506, with survival of all 14 patients. With all of the organ systems so far tested, including the kidney (which has been reported elsewhere), rejection usually has been controlled without additional drugs and with lower average steroid doses than in the past. Nephrotoxicity has been observed, but not to an alarming degree, and there has been a notable absence of hypertension. There is a suggestion that serum cholesterol may be lowered by FK 506, but this is unproved. Although the adverse reactions of FK 506 and the immunosuppressive mechanisms resemble those of cyclosporine, our preliminary observations suggest that FK 506 may have a more advantageous therapeutic index.

The adverse impact on liver transplantation of using positive cytotoxic crossmatch donors

Because of the liver grafts ability to resist cytotoxic antibody-mediated rejection, it has become dogma that the conventional transplant crossmatch used to avoid hyperacute rejection of other organs is irrelevant to the liver. We examined this hypothesis in a consecutive series of adult primary liver recipients treated with FK506 and low-dose steroids. Twenty-five of 231 (10.8%) patients received a liver from a cytotoxic-positive crossmatch donor (more than 50% of donor T lymphocytes were killed by dithiothreitol-pretreated recipient serum). The outcome was compared with that of 50 negative crossmatch patients who had their transplantations just before and after the crossmatch positive cases. The one-year graft and patient survivals were 56% and 68%, for positive and 82% and 86% for negative crossmatch patients (P = 0.004, P = 0.03, respectively). The difference between patient and first graft survival was accounted for by retransplantation, which was 4 times more frequent in the positive-crossmatch cases. Histologically, failed allografts obtained at the time of retransplantation revealed a spectrum of pathologic findings related to vascular injury. This study showed a higher difficulty of intraoperative blood product management, a degraded prognosis, and a poorer average quality of ultimate graft function when liver transplantation was performed against positive cytotoxic crossmatches. In such patients for whom crossmatch-negative donors may never be found because of the broad extent and intensity of sensitization, special therapeutic strategies perioperatively must be evolved if results are to improve.

Conversion of liver allograft recipients from cyclosporine to FK506 immunosuppressive therapy : a clinicopathologic study of 96 patients

The effect of conversion from cyclosporine-steroid immunosuppression to the new agent FK506 was studied in 96 liver allograft recipients who were experiencing graft dysfunction or cyclosporine toxicity. Patients were stratified according to the cause of graft dysfunction that ultimately led to conversion to FK506. Response to FK506 introduction was monitored pathologically and biochemically. The outcome of a switch from CsA to FK506 was highly favorable in patients experiencing acute and the early stages of chronic rejection, despite optimal conventional therapy. Patients with later stages of chronic rejection did not respond to conversion to FK506 and most eventually lost their liver grafts in this process. Patients in whom we had difficulty separating chronic rejection from chronic persistent or low-grade chronic active hepatitis were mostly unaffected by conversion to FK506. Active hepatitis was a poor indication for conversion, because most of the patients experienced graft failure or died from liver failure. As a group, there was no statistically significant change in renal function 180 days after conversion to FK506. These findings expand the experience with FK506 in human liver allograft recipients.

The effect of graft function on FK506 plasma levels, dosages, and renal function, with particular reference to the liver

Plasma FK506 was studied in 49 liver, 13 heart, 3 double-lung or heart-lung, and 21 kidney recipients. The levels were correlated with the drug doses used, kidney function, and liver function. In all verieties of recipients, there was an early rise in the FK506 plasma levels that occurred at the time of intravenous administration of the drug. At the same time or shortly after, there were increases in serum creatinine that were transitory except in liver recipients with continuing suboptimal graft function. The quality of hepatic function dominated all aspects of FK506 management in the liver recipients. Those who received well-functioning grafts could be given about the same drug doses as recipients of kidneys and the thoracic organs. Liver recipients with defective grafts had astronomical rises in plasma FK506, a high incidence of renal failure, and probably increased neurotoxicity. In kidney transplant recipients, the FK506 plasma levels and doses were essentially the same in patients with prompt versus delayed renal function. These studies have highlighted the necessity, first of close pharmacologic monitoring of patients who are given FK506 in the presence of abnormal liver function, and second, of using smaller intravenous induction doses than in past practice.

Liver transplantation in positive cytotoxic crossmatch cases using FK506, high-dose steroids, and prostaglandin E1.

Although the liver is resistant. to antibody-mediated rejection (1), a significant adverse effect has been reported of its transplantation into recipients with preformed cytotoxic antibodies (2). We report here a strategy that appears to convert the prognosis in such potentially disadvantaged patients to essentially the same if not better than that in conventionally treated crossmatch-negative recipients. The crossmatch status was determined with recipient sera treated with dithiothreitol (DTT) (3). Four cohorts of adult liver recipients were studied. In all, intravenous FK506 was started with doses of 0.075 to 0.15 mg/kg/day, and converted to oral dosing after resumption of diet. Treatment was guided by plasma FK506 levels (target approximately 1 ng/ml), toxicity (primarily renal), the clinical status of the patient, and the quality of postoperative liver function (4). The 4 study groups (Table 1) differed in the cytotoxic crossmatch state (negative in group 1 only), the use of prostaglandin E1 (group 4 only), and the prophylactic use of methylprednisolone (MP). Low-dose MP was with 20 mg/day starting on the day of transplantation (most of group 1 and all of group 2). High-dose MP was with 1 g i.v. during operation, followed by a “burst” with 200 mg the first day and daily decreases of 40 mg until 20 mg/day was reached on the 6th day if the course was uneventful (groups 3 and 4). In group 4, i.v. PGE1 (Prostin VR) was started after completion of the operation with 0.2 µg/kg/hr and gradually increased to 0.6 µg/kg/hr if tolerated without cardiovascular instability. One of the 14 patients in group 4 had transient hypotension. There were no other side effects of PGE1 which was stopped without weaning when the patients resumed diet after 5–7 days. TABLE 1 T lymphocytotoxic crossmatch state The crossmatch positive cases in groups 2–4 were consecutive, with no omissions. The incidences of hepatic malignancy, high UNOS urgency scores (50–78% III or IV), and cytotoxic titers > 1:8 were similar in the cytotoxic groups 2–4. Females were disproportionately represented in all of the crossmatch-positive groups compared with crossmatch-negative controls. In the crossmatch-positive cases, the outcome was remarkably different according to treatment (Table 1). With high-dose steroid therapy (group 3), the unacceptably high early and delayed graft loss seen with low-dose steroid therapy (group 2) was reduced by two-thirds. Graft loss was reduced further if PGE1 was added to the high-dose steroid regimen (group 4). The only death in the 14 patients of group 4 was caused by a biliary leak and subhepatic infection in a patient whose native gall bladder had empyema. The favorable course of the group 4 recipients relative even to group 3 and especially group 2 patients was reflected by an improvement in the perioperative renal function (Fig. 1), and superior postoperative liver function (Fig. 2). FIGURE 1 First-week FK506 doses and plasma concentrations and serum creatinine (Cr) in crossmatch-positive liver recipients (groups 2, 3, 4). (Cr)—group 2 vs. 3 P<0.0001, 2 vs. 4 P<0.0001, 3 vs. 4 = P = 0.007. FK506 dose—2 vs. 3 ... FIGURE 2 Serum total bilirubin (1st month) and serum GOT levels (2 weeks) in crossmatch-positive liver recipients. Bilirubin in first week—group 2 vs. 3 P = 0.007, 2 vs. 4 P<0.01, 3 vs. 4 P=0.36. SGOT in first week—group 2 vs. 3 P=0.36, ... The superior renal function in the liver recipients of group 4 was noteworthy. It is possible the PGE1 specifically protects the kidneys from FK506 nephrotoxicity by a mechanism similar to that described by Makowka et al. (5) for cyclosporine. However, protection of the liver graft from antibody-mediated rejection and consequent avoidance of prerenal complications may have been a significant or even more important factor. The pathogenesis of hyperacute rejection of kidney grafts, and the much slower manifestations of antibody-mediated rejection seen in liver grafts are not fully understood (6). Whatever the mechanisms, it has been known since the earliest work of Dempster (7) that intense vasoconstriction occurs of the graft microvasculature (8). PGE1 treatment added to FK506 and high doses of steroids could have ameliorated this consequence, aside from its inherent immunosuppressive (9) and cytoprotective (10) qualities. Amelioration by PGE1 of humoral rejection has not been reported clinically, but there have been clues of its potential value in xenograft transplant models that have heterospecific antibody barriers, including cat-to-dog (11), hamster-to-rat (12), and pig-to-dog (13). High-dose prednisone in conjunction with FK506 but without PGE1 also was effective. The steroid mitigation of humoral rejection presumably was by different pathways although both glucocorticoids and PGE suppress cytokines (14, 15). Accurate delineation of these drug actions and interactions will be of the greatest interest in providing clues for other therapeutic improvements. At a practical level, the experience reported herein indicates not only the feasibility but also the surprising ease with which the liver can be transplanted to sensitized recipients. If optimum therapy is given, a policy of excluding patients with widely reacting cytotoxic antibodies from candidacy for liver transplantation would seem unwarranted. The results in the high-dose steroid-PGE1 group 4 were at least as good as in the cases with negative crossmatches. Whether all liver transplantations, including those with crossmatch-negative donors should be given this treatment deserves consideration. PGE1 already has been used in this way in cyclosporine-based drug cocktails for crossmatch-negative kidney transplantation (16). There were no obvious artifacts that would undermine these conclusions, such as the use in later cases of a different titer cutoff for a positive-crossmatch reading. About the same percentage of titers greater than 1:8 were in groups 2–4, but the highest positive titer was not measured systematically at the time of the case accrual. In 6 subsequent patients who were given the optimal recommended treatment and who had titers equal to or greater than 1:256, only 1 had a humoral rejection. This was a female patient with a titer of 1:1024 who required retransplantation 2 days after primary graft nonfunction, using a crossmatch-positive donor liver (titer 1:2) on the second occasion. She is well 4 months later. The influence of titers, different sensitization schedules, and the nature of the antibody upon humoral rejection of the liver in rats has been described elsewhere.4 These experimental studies, combined with our clinical experience herein reported, have led to our present policy of not delaying urgently needed liver transplantation in order to search for a more appropriately crossmatched donor.

Proteasome inhibitor MG-132 enhances the expression of interleukin-6 in human umbilical vein endothelial cells: Involvement of MAP/ERK kinase

Interleukin‐6 (IL‐6) is a multifunctional cytokine that plays an important role in inflammatory reactions. We have addressed the possible regulation of IL‐6 expression by the ubiquitin‐protease system in human umbilical vein endothelial cells. Cultured endothelial cells were treated with MG‐132, a protease inhibitor, and the levels of IL‐6 mRNA and protein were measured by reverse transcription‐PCR and ELISA. MG‐132 increased the expression of IL‐6 mRNA and protein; and this effect was abolished by the pretreatment of the cells with U0126, an inhibitor of MAP or ERK kinases (MEK1/2). MG‐132 treatment was also found to enhance the level of phosphorylated MEK1/2. Treatment of the cells with actinomycin D inhibited IL‐6 expression in response to MG‐132, suggesting the transcriptional upregulation of IL‐6 under proteasomal inhibition. We conclude that a protease inhibitor MG‐132 upregulates IL‐6 expression in vascular endothelial cells, at least in part, through the activation of MEK1/2.

Increased Bile Duct Complications and/or Chronic Rejection in Crossmatch Positive Human Liver Allografts

Bile duct complications continue to be a significant cause of bile morbidity after orthotopic liver transplantation, with an incidence of 7% to 34% of patients. 1,2 Bile of duct obstruction, usually due to strictures, biliary leakage, and/or cholangitis, accounts for the majority of these complications. In contrast, although low incidence of chronic rejection has been reported under FK 506-based immunosuppression in early trials of liver transplantation, 3 chronic rejection after liver transplantation occurs in only 5% to 9% of cases, and it remains one of the most common causes of graft loss. 4,5 There have been many conflicting recent reports concerning a relationship between the bile duct-related complications or ductopenic chronic rejection and a positive crossmatch. 6–8 . We investigated the outcome of liver grafts from positive crossmatch donors, focusing on biliary complications and ductopenic chronic rejection, and we compared the results to a consecutive negative cross-match control group at the same time.

The relationship of systemic hemodynamics and oxygen consumption to early allograft failure after liver transplantation

The early postoperative hemodynamic data of 88 patients who underwent primary liver transplantation between July 1989 and October 1990 at the University Health Center of Pittsburgh were analyzed to establish the relationship of systemic hemodynamics and oxygen consumption to perioperative allograft function. The 15 patients whose allografts failed within the 1 st month following transplantation were designated as group 1, while 73 patients who retained adequate graft function constituted group 2. Although the cardiac index and oxygen delivery did not differ significantly between the groups, group 1 consistently demonstrated a lower mean arterial pressure, oxygen consumption, arteriovenous oxygen content difference, and arterial ketone body ratio. The etiology of reduced oxygen consumption in group 1 patients is speculative, but the data support the notion that oxygen consumption is a useful, predictive indicator for liver allograft function after transplantation.

Replacement of the Canine Inferior Vena Cava with a Seeded Graft

Abstract The patency and microscopic findings of gelatin-coated Dacron grafts seeded with endothelial cells and implanted into the inferior vena cava of dogs was evaluated. A total of 25 mongrel dogs were divided into four experimental groups according to whether or not an antiplatelet agent was administered and a seeded or nonseeded graft was implanted. In the groups not given antiplatelet therapy that were implanted with a nonseeded graft, occlusion of the graft occurred soon after surgery. In contrast, in the majority of animals implanted with a seeded graft and given antiplatelet therapy, graft patency was evident for up to 4 weeks postoperatively. In the latter animals, scanning electron microscopy 4 weeks after surgery showed the formation of confluent endothelial-like cells within 5 mm from the anastomosis, as well as insular endothelial-like cells in the central part of the graft. The simple centrifugal seeding method enables endothelial-like cells to adhere to grafts, suggesting that it may be useful in venous replacement.

Mycotic Inferior Mesenteric Aneurysm Penetrating to Duodenum: Observation of the Formative Course

症例は64歳, 女性. 腰痛, 発熱で発症し, 腹部CT上, 腎動脈下大動脈および下腸間膜動脈起始部の周囲 の低吸収域と, 肝門部の肝膿瘍を認めた. 入院当初より感染性動脈瘤を疑っていたが, 確診は得られず, 抗 生剤の投与を開始した. 炎症所見の消退と解熱がみられたが, 第12病 日に吐血 し, ショック状態となった. 緊急CTを 施行 したところ, 腹部大動脈周囲低吸収域は拡大 し, 下腸間膜動脈根部に最大径16mmの 拡 張 ・瘤化が認められた. 感染性動脈瘤切迫破裂の診断のもと, 緊急手術を施行 した. 腹部大動脈周囲には壊 死組織 と血塊からなる6cmの 腫瘤を認め, 腫瘤は十二指腸水平脚に接 していた. 大動脈内腔には潰瘍形成 を認め, 十二指腸へ穿通 していた. 腹部大動脈を腎動脈下大動脈と大動脈末端で縫合閉鎖し, 左腋窩-大腿 動脈バイパスをおいた. 開放 した腹部大動脈と十二指腸の間には大網を充填 した. 大動脈周囲壊死組織の培 養検査では, Klebsiella pneumoniae が検出され, 抗生剤の投与を継続 した. 術後経過は良好で, 術後46 日目に退院した. 感染性動脈瘤の十二指腸穿通例は死亡率も高 く予後不良であり, 早期診断, 治療開始が最 も肝要と考えられる. 感染初期から感染性動脈瘤形成および十二指腸穿通までの経時的経過を観察 し, 緊急 手術により救命しえたので報告する. 日心外会誌33巻4号=287-290(2004)