Showing papers in "Transplantation in 1993"

Risk factors for primary dysfunction after liver transplantation--a multivariate analysis.

Abstract: In a retrospective analysis on 323 orthotopic liver transplant procedures performed between July 1984 and October 1991 the incidence of two forms of primary dysfunction (PDF) of the liver: primary nonfunction (PNF), and initial poor function (IPF) were studied. The incidence of PDF was 22% (73/323) with 6% PNF (20/323) and 16% IPF (53/323), while 78% (250/323) had immediate function (IF). Occurrence of both IPF and PNF resulted in a higher graft failure rate (P 3 days), older donor age (> 49 years), extended preservation times (> 18 hr), and fatty changes in the donor liver biopsy, as well as reduced-size livers, younger recipient age, and renal insufficiency prior to OLTx, significantly affected the incidence of IPF and PNF. Multivariate analysis of potential risk factors showed that reduced-size liver (P = 0.0001), fatty changes on donor liver biopsy (P = 0.001), older donor age (P = 0.009), retransplantation (P = 0.01), renal insufficiency (P = 0.02), and prolonged cold ischemia times (P = 0.02) were independently associated with a higher incidence of IPF and PNF. No statistical correlation was found between PDF and etiology of ESLD, nutritional status of the recipient, UNOS status, and Child-Pugh classification in this study. We conclude that PNF and IPF are both separate clinical entities that have a significant effect on outcome after OLTx. Routine donor liver biopsies are recommended to decrease the rate of IPF and PNF. The combination of risk factors shown to be significant for PDF should be avoided--and, if that is not possible, the only variable that can be controlled, the preservation time, should be kept as short as possible.

Neutrophil infiltration as an important factor in liver ischemia and reperfusion injury. Modulating effects of FK506 and cyclosporine.

Abstract: To examine the role of neutrophils, their presence and the degree of infiltration, as important determinants of ischemia and reperfusion injury of the liver, male Sprague-Dawley rats were subjected to 60 and 90 min of total-liver ischemia. The presence of neutrophils, assessed by the measurement of liver tissue myeloperoxidase (MPO), and the degree of neutrophil liver infiltration, determined by the naphthol AS-D chloroacetate esterase technique, correlated well with animal survival and response to FK506 and cyclosporine administration. Lipid peroxidation, measured by the malondialdehyde (MDA) test in liver tissue, was another factor closely linked with liver function and survival. Pretreatment with FK506 (0.3 mg/kg) and CsA (5 mg/kg) was given at 4 hr and 1 hr before ischemia and at the time of reperfusion. Control ischemic animals showed increased neutrophil liver infiltration, high MPO and MDA liver levels, and diminished overall survival. FK506 and CsA-treated animals had better survival and diminished neutrophil liver infiltration, as well as MPO and MDA levels. The mechanism by which FK506 and CsA protected the animals from severe liver ischemic injury is unknown. Our data indicated that the presence and the degree of infiltration of neutrophils were important components of liver ischemia/reperfusion injury in the rat. So it is possible that one of the fundamental effects of the FK506 and CsA might be through the inhibition of the presence and infiltration of neutrophils in liver tissue.

Risk factors for chronic rejection in renal allograft recipients.

Abstract: Chronic rejection is a major barrier to long-term renal allograft survival. Cyclosporine, though effective at reducing graft loss to acute rejection, has had little impact on the incidence of chronic rejection. Between June 2, 1986 and January 22, 1991, 587 kidney-alone transplants (566 patients) were performed, and had been entered into our renal transplant database and had at least 1 year of follow-up: 103 with biopsy-proven chronic rejection (37 living-related donor, 66 cadaver) and 484 without chronic rejection (236 LRD 248 CAD). The 5-year patient survival was 84% for recipients with biopsy-proven chronic rejection vs. 89% without (P = .08). The 5-year graft survival was 31% for recipients with biopsy-proven chronic rejection vs. 81% without (P 50 years), gender, human leukocyte antigen matching, peak and transplant panel-reactive antibody, acute rejection episodes, infections (including cytomegalovirus, viral, and bacterial), donor age, and CsA dosage at 1 year ( or = 5 mg/kg). Logistic regression models were fit to the data using a forward stepwise selection procedure. In this analysis, risk factors included an acute rejection episode (P < .001), CsA dosage < 5 mg/kg/day at 1 year (P = .007), infection (P = .023), female gender (P = .042), and retransplant (P = .103). Individual analyses were done for CAD and LRD recipients. For both groups, important variables were acute rejection, infection, CsA dosage at 1 year, and age at transplant. In conclusion, acute rejection, CsA dosage < 5 mg/kg/day at 1 year, and infection are the major risk factors for the development of chronic rejection, suggesting that chronic rejection may be the result of inadequate immunosuppression (acute rejection episodes and low CsA dosage) or the production of inflammatory cytokines (infections).

Carbohydrate antigens of pig tissues reacting with human natural antibodies as potential targets for hyperacute vascular rejection in pig-to-man organ xenotransplantation.

Abstract: Pig tissues were screened by immunofluorescence with lectins, mAb, and human natural antibodies for the presence of carbohydrate antigens, which may be potential targets for hyperacute vascular rejection in pig to man xenotransplantation. The unfucosylated monomorph linear B-antigen was found at the surface of all porcine vascular endothelial cells. This pig linear-B antigen reacts strongly with the anti-alpha Gal isolectin B4 from Griffonia simplicifolia 1 and with human natural anti-alpha Gal antibodies specifically purified by affinity chromatography on synthetic oligosaccharides containing the terminal nonreducing alpha Gal1-->3 beta Gal-R disaccharide. This antigenic activity is destroyed by treatment of pig tissues with alpha-galactosidase. The localization of this linear-B epitope on vascular endothelium and its reactivity with natural human anti-alpha Gal antibodies suggest that it may play a major role in the hyperacute vascular rejection of pig to man organ xenografts. The lectin from Maackia amurensis reacting with alpha NeuAc2-->3 beta Gal1-->4GlcNAc/Glc was also positive on pig vascular endothelium, but we do not know yet whether there are human natural antibodies reacting with the carbohydrate recognized by this lectin. Epithelial cells of pig renal proximal convoluted tubules, respiratory epithelium, pancreatic ducts, and epidermis express the linear-B antigen, but they are less likely to trigger a hyperacute vascular rejection because they are not directly exposed to the blood. The genetically defined pig A+/A- system controls the expression of A and H antigens in pig epithelial cells from renal distal and collecting tubules, biliary ducts, pancreatic ducts, large bronchi, and digestive mucosa. The pig A antigen may trigger an immune response in human O or B recipients if they are transplanted with organs from A+ pigs, but the pig A antigen is probably not involved in the hyperacute vascular rejection of a xenograft because it is not expressed on vascular endothelium.

Early versus late acute renal allograft rejection: impact on chronic rejection.

Abstract: We studied the effect of acute renal allograft rejection and its timing on the development of chronic rejection and subsequent graft loss. Between January 1, 1987 and April 30, 1991, 424 patients at the University of Minnesota received a primary kidney transplant (minimum follow-up, 1 year). Patients were subdivided by donor source, presence or absence of acute rejection, and the timing of acute rejection onset (early, 60 days post-transplant). For living donor (LD) transplant recipients (n = 219), the incidence of chronic rejection is 0.8% in those who had no acute rejection (n = 130), 20% in those with acute rejection 60 days (n = 30) (P 60 days (n = 27) (P 1 acute rejection episode had significantly more chronic rejection than those with only 1 rejection (P 60 days (vs. < or = 60 days) have an increased incidence of chronic rejection.

Chimerism and donor-specific nonreactivity 27 to 29 years after kidney allotransplantation.

Abstract: Chimerism was demonstrated with immunocytochemical and/or polymerase chain reaction techniques in kidney allografts and in the native skin, lymph nodes, or blood of 5 of 5 patients who received continuously functioning renal transplants from 1 or 2 haplotype HLA mismatched consanguineous donors (4 parents, 1 aunt) 27–29 years ago. In the 4 cases where the kidney donor still was alive to provide stimulator lymphocytes for testing, these provoked no (n=2) or modest (n=2) MLR in contrast to vigorous MLR to third party lymphocytes. In all 4 cases, the donor cells failed to generate in vitro cytotoxic effector cells (cell-mediated lymphocytotoxicity). These findings are in accord with the hypothesis that cell migration, repopulation, and chimerism are seminal events that define graft acceptance and ultimately can lead to acquired donor-specific nonresponsiveness (tolerance).

Prolongation of cardiac xenograft survival by depletion of complement

Abstract: Complement (C) activation is thought to be critical for the hyperacute rejection of xenografts. We investigated the role of C in the rejection of discordant cardiac xenografts by studying outcome in recipients depleted of C, using a highly purified form of cobra venom factor (CVF) in both a small (guinea pig [GP]-to-rat) and large (pig-to-baboon) animal model. A single dose of 30 or 60 units CVF given i.v. to rats completely abrogated hemolytic C activity for up to 72 hr. The lack of hemolytic C activity correlated with nearly undetectable serum levels of C3. Doses of 30 U/kg daily or 60 U/kg every other day over a 7-day period sustained C depletion without morbidity or mortality

A phase I trial of immunosuppression with anti-ICAM-1 (CD54) mAb in renal allograft recipients.

Abstract: Several adhesion molecules contribute to the interaction between T cells and antigen presenting cells of target cells. Leukocyte function-associated molecule-1 (LFA-1[CD11a/CD18]) and intercellular adhesion molecule-1 (ICAM-1 [CD54]) are one such critical adhesive receptor-counter-receptor combination. The importance of ICBM-1 dependent adhesion in the rejection response was initially demonstrated in cynomolgus renal allograft recipients treated with the anti-ICAM-1 murine monoclonal antibody BIRR1. BIRR1 also appeared to limit ischemic damage in these animals. B Phase I clinical trial has subsequently been completed in 18 patients who received cadaver donor renal allografts at high risk for delayed graft function (prolonged preservation time, highly-sensitized recipient)

The effect of immunosuppression on pre-existing cancers.

Abstract: This study of 939 pre-existing malignancies that occurred in 913 renal transplant recipients showed that in 823 patients the tumors were treated prior to or at transplantation, in 78 after transplantation, at an unspecified time in 20, while 18 received no treatment. Of patients treated pretransplantation 185 (22%) developed recurrences posttransplantation. Low recurrence rates (0-10%) occurred with incidentally discovered renal tumors; lymphomas; and testicular, uterine cervical, and thyroid carcinomas. Intermediate recurrence rates (11-25%) occurred with carcinomas of the uterine body; Wilms' tumors; and carcinomas of the colon, prostate, and breast. High recurrence rates (> or = 26%) occurred with carcinomas of the bladder, sarcomas, malignant melanomas, symptomatic renal carcinomas, nonmelanomatous skin cancers, and myelomas. Overall 53% of 185 recurrences occurred in patients treated 0-24 months pretransplantation, 34% in patients treated 25-60 months pretransplantation, and 13% in patients treated > 60 months pretransplantation. Of 78 patients whose cancers were first treated after transplantation, 27% developed recurrences. However, 63% did not do so in follow-ups averaging 53 months. A two-year waiting period between treatment of cancer and transplantation is justified for most neoplasms except for incidentally discovered renal carcinomas, in situ carcinomas, and possibly focal neoplasms (a small single focus), low-grade bladder cancers, and basal cell skin cancers. In these cases no waiting period is necessary. On the other hand, a waiting period > 2 years is necessary for most malignant melanomas, breast carcinomas, and colorectal carcinomas. Conflicting data are presented as to whether immunosuppression affects growth of existing tumor cells but most of the evidence suggests acceleration of neoplastic growth.

A study of treatment compliance following kidney transplantation

Abstract: Kidney transplantation is a successful treatment for end-stage renal disease. We studied demographic and psychosocial variables that relate to compliance behaviors following renal transplant. One hundred and five renal allograft recipients, with a minimum of 18 months follow-up, were studied. A biographical questionnaire, the Center for Epidemiologic Studies Depression Scale, the Multidimensional Health Locus of Control Scale, and the Social Support Appraisals Questionnaire were used as measuring instruments. Specifically for this study, we designed a Health Belief Model Questionnaire, a Patient and Provider Relationship Questionnaire, a Compliance Self-Report Questionnaire, and a Self-Efficacy Questionnaire. Compliance was determined by cyclosporine whole blood levels > 30 ng/ml, maintenance of ideal body weight ( 20% of clinic visits. Discriminant function analysis distinguished patients who were compliant from those who were not. Males were more likely to be noncompliant with medication, whereas females were more likely to be noncompliant with diet. Noncompliance was also associated with increased numbers of prescribed medications, depression, black race, locus of control attributed to powerful others, unemployment, as well as the perceived amount of social and family support. Patients with failed grafts (n = 14) were more depressed (P < 0.05), perceived less benefit from the treatment regimen (P < 0.01), and had less confidence in their care providers (P < 0.05) than those recipients of successful grafts (n = 91). In conclusion, this study identifies a number of psychosocial and demographic variables that impact on patient compliance behaviors after renal transplant. Interventional strategies to obviate noncompliance will need to consider these heterogeneous variables in order to maximize long-term renal allograft survival.

The impact of acute rejection episodes on long-term graft function and outcome in 1347 primary renal transplants treated by 3 cyclosporine regimens.

Abstract: To characterize factors of importance for the occurrence of acute rejection as well as study the impact of these episodes on long-term renal survival and function, a total of 819 acute rejection episodes were studied in 951 primary cadaveric donor kidney recipients (CD) and in 396 primary living donor kidney recipients (LD). The patients were treated by three immunosuppressive schedules, namely, CsA given in a high dose, a medium dose, or a low dose. Additionally, all patients received PRED and patients in the low-dose group received AZA. The incidence of acute rejection was higher and occurred earlier after transplantation in the CsA medium dose and low dose groups than in the CsA high dose group (P < 0.05 and P < 0.01, respectively). Although the incidence of first acute rejection was similar in CD and LD patients, 59.1% vs. 60.6%, it was successfully reversed by antirejection treatment in a higher percentage in LD patients. The estimated graft half-life was shorter in patients who had acute rejection episodes than those who did not, 6.6 years vs. 12.5 years in CD patients (P < 0.0001). Renal function at 1-5 years after transplantation was stable, but significantly poorer in CD patients who had experienced acute rejection than in patients who had not, with the mean creatinine clearance rates in the ranges 45-47 vs. 54-60 ml/min in the other groups (P < 0.0001). In a stepwise Cox regression analysis in CD recipients, risk factors for acute rejection were CsA (low dose) treatment schedule, immunization as displayed by presence of panel-reactive antibodies and positive B cell cross-match, young recipient age, disease of diabetes mellitus, and HLA-DR mismatching. In LD recipients, the corresponding risk factors were treatment schedule, young recipient, HLA mismatching, and transplantation from parent to child. Thus, the study has demonstrated some factors of importance for acute rejection episodes in CsA-treated patients as well as showing the detrimental effect of these episodes on long-term graft survival and renal function. These results suggest that a primary aim of future treatment strategies should be to reduce the incidence of these episodes.

Rapamycin Inhibits Arterial Intimal Thickening Caused By Both Alloimmune And Mechanical Injury: Its Effect On Cellular, Growth Factor, And Cytokine Responses In Injured Vessels

Abstract: The effect of rapamycin (RPM) on the extent of arterial intimal thickening was determined in rat recipients of orthotopic femoral artery allografts or in rats that had undergone balloon catheter injury to carotid arteries. In untreated rats, neointima comprised approximately 50% of the arterial wall area in both models. Although treatment of allograft recipients for 40 days with 1.5 mg/kg/day RPM was ineffective, a dose of 6 mg/kg/day (days 0-7) followed by 3 mg/kg/day (days 8-39) reduced intimal thickening by 98% (P < 0.0001). The higher RPM dose reduced T cell and macrophage infiltration significantly and decreased the expression of IL-2 receptor, class II Ag, and mRNAs for growth factors and cytokines. Treatment with 1.5 mg/kg/day RPM (days 0-13) after balloon-catheter injury reduced intimal thickening by 45% (P = 0.0254) and substantially decreased macrophage infiltration and expression of class II Ag in the adventitia. Within the neointima, however, mRNAs for platelet-derived growth factor-alpha, basic fibroblast growth factor, and transforming growth factor-beta were still expressed. In summary, we have shown that RPM inhibits not only the vascular response to injury caused by allograft rejection, but also the response to balloon catheter injury. This new information is important to our understanding of: (1) the fundamental processes responsible for intimal thickening regardless of the cause of vascular injury, (2) mechanisms of action of RPM that explain its effects on the response to very different types of vascular injury, and (3) the potentially diverse therapeutic applications of drugs, like RPM, that inhibit the actions of both immune and nonimmune cytokines and growth factors.

Cytokines, adhesion molecules, and the pathogenesis of chronic rejection of rat renal allografts.

Abstract: Little is known of the host immune mechanisms responsible for initiation and progression of chronic rejection. We describe immunopathologic features associated with progressively deteriorating function of kidney allografts in the F344-to-Lewis rat strain combination, which differ at MHC and non-MHC loci. Initial rejection in untreated recipients was controlled by a brief course of CsA (5 mg/kg/day, for 10 days), resulting in > 80% of recipients surviving up to a year despite declining renal function. In contrast to controls (isografts placed in untreated or CsA-treated Lewis rats), allografts from 12-16 weeks post-Tx showed segmental or global glomerulosclerosis, increasing tubular atrophy, interstitial fibrosis, and intimal proliferation leading ultimately to vascular occlusion. By flow cytometry, IgM and IgG alloantibodies peaked at 2-4 weeks, with a gradual decline to baseline thereafter. Immunohistology showed early and progressive deposition of IgM, IgG, C3, and fibrin in vessel walls and glomeruli. In addition, by 12 weeks, extensive infiltration by activated (IL-2R+) macrophages and CD4+ T cells were noted in glomeruli and blood vessels, in conjunction with staining for the cytokines TNF-alpha, IL-1, and IL-6. The persistent and dense intraglomerular expression of IL-6 was of particular interest, given its potent mitogenic effects for mesangial cells in vitro, and suggests a role for this cytokine as a mediator of mesangial expansion, advanced glomerular injury, and glomerulosclerosis in chronic rejection. Parallel timing of IL-6 and TNF-alpha expression was shown in serum samples by ELISA and bioassays. In vitro binding studies showed increased binding of naive host lymphocytes to allograft versus isografts, correlating with upregulation (peaking at week 16) of intercellular adhesion molecule-1 expression by graft endothelium. We conclude that cytokine production and upregulation of adhesion molecules occurring as part of a cellular immune response may be as important to the etiology of chronic rejection as the hitherto widely emphasized antibody-mediated host responses.

Post-transplant lymphoproliferative disorder in renal allograft recipients. Clinical experience and risk factor analysis in a single center.

Abstract: Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized complication of solid organ transplantation. The University of Alberta Renal Transplant Program had not experienced a case of PTLD occurring in the early post-transplant period until March 1989. Since then, 4 patients have developed this complication. To identify the major risk factors for the recent appearance of PTLD, a retrospective analysis was carried out on 162 cadaveric renal transplants performed between July 1987 and December 1990. Four cases of polymorphic PTLD were seen. Two patients presented with fatal disseminated disease. Two others developed PTLD confined to the renal allograft; both are disease free at > 24 months of follow-up. Seventy-two (44.4%) of the cadaveric transplant recipients had received Minnesota antilymphocyte globulin (MALG) induction therapy during the study period. Twenty-four of these also received OKT3 for steroid-resistant rejection. Of the 4 patients with PTLD, 3 had received both MALG induction and OKT3; the remaining patient had received MALG induction only. The incidence of PTLD in the MALG/OKT3 group was 12.5%, which is significantly higher than that of patients receiving other immunosuppressive regimes (0.7%, P = 0.015). The incidence of PTLD was also significantly greater in the 13 patients at risk for primary EBV infection compared to the EBV seropositive patients (23.1 vs. 0.7%, P = 0.002). Only 2 seronegative patients received sequential MALG/OKT3; both developed PTLD. Thus, the population most at risk is that receiving potent antilymphocyte preparations in the setting of primary EBV infection. Allograft involvement with PTLD must be considered in the differential diagnosis of allograft dysfunction, as early diagnosis may permit the successful management of this complication.

The immunopathology of cardiac xenograft rejection in the guinea pig-to-rat model

Abstract: The mechanisms underlying rejection by rats of vascularized guinea pig xenografts have been controversial. The aim of this study was to define, using sequential immunopathologic analysis, the contributions of xenoreactive antibody, complement, and effector cells to the rejection of guinea pig cardiac xenografts by Lewis rats. In untreated recipients, hyperacute rejection of guinea pig cardiac xenografts occurred in 20 +/- 10.2 min and was characterized by focal endothelial deposition of IgM and by diffuse deposition of C3. IgG was not localized to endothelial surfaces, but was present in the same locations as albumin, suggesting that the accumulation of IgG might reflect nonspecific leakage of plasma proteins from blood vessels. No polymorphonuclear or monocytic infiltrate was observed. Depletion from rats of xenoreactive antibody to undetectable levels prolonged the survival of guinea pig cardiac xenografts, but did not prevent hyperacute rejection; the rejected xenografts contained deposits of C3 along the microvasculature but no deposits of IgM or IgG. No cellular infiltrate was observed. Depletion of complement with cobra venom factor prolonged the survival of xenografts up to 96 hr. Xenograft tissues from complement-depleted animals had diffuse deposits of IgM along the microvasculature, but no detectable deposits of C3 or IgG were noted. Graft tissues obtained at various times after transplantation into complement-depleted animals revealed cellular infiltrates consisting of granulocytes, monocytes, and lymphocytes, but few cells bearing an NK cell phenotype. Our findings are consistent with the concept that complement activation is essential for the hyperacute rejection of discordant xenografts, and that in this particular model complement activation can proceed without the involvement of antibody. However, our findings also suggest that xenoreactive antibody contributes to hyperacute rejection and, along with effector cells, contributes to the later rejection of a xenograft when hyperacute rejection has been averted. Finally, we show that when hyperacute rejection is avoided, a form of vascular rejection occurs in which certain of the pathologic features--i.e., interstitial hemorrhage, interstitial edema, and thrombosis--are very similar to those observed in hyperacute rejection. Whether this form of rejection is a delayed form of the process that leads to hyperacute rejection or a novel pathologic process of graft rejection has yet to be determined.

Hepatic microcirculatory changes after reperfusion in fatty and normal liver transplantation in the rat.

Abstract: The hepatic microcirculation in fatty and normal liver grafts in ACI rats was investigated using in vivo microscopy. Six groups were studied. They were: normal and fatty control livers (sham operated), 6-hr cold University of Wisconsin solution (UW)-preserved fatty and normal liver grafts (survival conditions, fatty and normal liver grafts), 18-hr cold UW-preserved fatty livers (nonsurvival conditions, fatty liver graft), and 24-hr cold UW-preserved normal livers (nonsurvival conditions, normal liver grafts). Fatty livers in all groups were found to have narrow and irregular sinusoids with blood cell adhesions to endothelial cells. The number of adhesions increased as the preservation time increased. Sinusoidal blood flow area decreased as the preservation time increased and was correlated with survival in both normal and fatty liver grafts. The phagocytic activity of Kupffer cells (corrected for flow) increased as the preservation time increased. The phagocytic Kupffer cell activity of the 18-hr preserved fatty liver group was greater than the activity of any other group. These features may cause liver cell death and contribute to primary graft nonfunction after transplantation of a fatty liver.

Cytomegalovirus infection--an etiological factor for rejection? A prospective study in 242 renal transplant patients.

Abstract: The study aimed at analyzing the role of CMV infection as a risk factor for rejection occurring after CMV infection because of the clinical consequences of the prevention of CMV infection that might lead to the decrease in rejection episodes. Two hundred forty-two consecutive renal transplant patients were prospectively checked for the occurrence of CMV infection. CMV infection was defined virologically by a positive viremia or/and a positive viruria or/and a seroconversion or/and a significant rise of the anti-CMV antibody titers. Viremia, viruria, and serology were performed weekly for the first month and then at day 90, day 180, and every 6 months, and moreover if clinical symptoms related to a viral infection occurred. Rejection episode was defined by a creatininemia rise of 25%, after cyclosporine nephrotoxicity and urological complications had been discarded, and by the response to the antirejection therapy, steroids, or OKT3 in case of steroid-resistant rejection. The outcome factor was rejection episode occurring from day 4 after the diagnosis of CMV infection. A patient undergoing "a rejection episode after CMV infection" could also be exposed to other potential confounding factors that can be considered as risk factors of rejection among our patients. Rejection occurring before CMV infection was the main factor because it was linked both to CMV infection itself and to "rejection after." Thus infected and noninfected patients were randomly paired off. To the noninfected patient of the pair was attributed the date of a fictitious CMV infection that was the date of the CMV infection of the infected member of the pair. Therefore, "rejection after" and "rejection before" were defined in infected and noninfected patients of the pair according to the time of onset of CMV infection of the infected member of the pair. The incidence of CMV infection was 65%, 157 of the 242 patients were infected, and 85 not infected. Thus 85 pairs of infected-noninfected patients were studied. The incidence of "rejection after" the diagnosis of CMV infection was significantly higher in the group of patients with CMV infection: 45% among infected (38/85) versus 10.60% among noninfected (9/85) (P < 0.0001). Among the 85 pairs, 48 pairs were concordant in which patient of the pair evinced the same outcome factor: 43 showed no rejection after, and 5 showed one.(ABSTRACT TRUNCATED AT 400 WORDS)

The greater vulnerability of bile duct cells to reoxygenation injury than to anoxia. Implications for the pathogenesis of biliary strictures after liver transplantation.

Abstract: The occurrence of biliary strictures in allografts following liver transplantation correlates with the duration of preservation time. The correlation between preservation time and biliary strictures suggests that anoxic or reperfusion injury of the bile duct epithelium causes stricture formation. However, the relative susceptibility of bile duct cells to anoxic or reoxygenation injury is unknown. Our aims were to determine the vulnerability of rat liver bile duct cells to anoxic and reoxygenation injury and to compare the results with hepatocytes. During anoxia, bile duct epithelial cells were significantly more resistant to cell killing than hepatocytes. Rates of cellular proteolysis were also 2.5-fold lower in bile duct cells than in hepatocytes during anoxia. In contrast to anoxia, reoxygenation of anoxic cells increased cell killing of bile duct cells but improved viability of hepatocytes. The rate of toxic oxygen species formation by bile duct cells was 5-fold greater than in hepatocytes during reoxygenation. In addition, basal levels of glutathione are lower in bile duct cells than in hepatocytes. These data suggest that bile duct cells are more susceptible to reoxygenation injury than to anoxia. These studies support the hypothesis that reoxygenation injury during liver preservation leads to bile duct injury during liver transplantation.

Cytomegalovirus pneumonia after bone marrow transplantation. Risk factors and response to therapy.

Abstract: Cytomegalovirus pneumonia complicated bone marrow transplantation in 75 (63 allogeneic and 12 autologous) of 1136 recipients (Kaplan-Meier incidence 8.8%). CMV pneumonia occurred more frequently in allogeneic (12.4%) than autologous recipients (3.3%). Increased risk for CMV pneumonia was observed in allogeneic recipients who were seropositive (relative risk = 2.9), older age (RR = 1.4 per decade), those conditioned with total-body irradiation (RR = 2.7), who received antithymocyte globulin (RR = 2.9) or T cell-depleted marrow (RR = 2.7) or who had CMV viruria (RR = 4.0) or viremia (RR = 5.9). Autologous recipients were also at increased risk if they were seropositive (RR = 6.1), or developed viruria (RR = 7.0) or viremia (RR = 15.4). Thirteen of 14 untreated patients died without improvement. Prognosis was poor in patients who were ventilator-dependent at initiation of therapy (median survival 17 days), with only 1 long-term survivor. In contrast, patients ventilator-independent at initiation of therapy with ganciclovir and immunoglobulin (n = 22) had a median survival of > 274 days, with 9 long-term survivors. Ganciclovir alone or acyclovir with immunoglobulin in ventilator-independent patients was less effective (median survivals 80 and 10 days, respectively). Overall, 10 of 75 patients were surviving 10-73 months (median 47) from diagnosis; 9 of these were ventilator-independent at initiation of therapy and received ganciclovir with immunoglobulin. CMV pneumonia was less common, but was severe in autologous recipients, with only 2 of 12 surviving. CMV pneumonia remains a prominent cause of death following BMT. Early therapy with ganciclovir and immunoglobulin before respiratory failure supervenes may improve survival.

Frozen section evaluation of donor livers before transplantation

Abstract: Frozen section examination was performed on 385 donor livers before transplantation. Exclusion criteria were applied to the donor livers examined to exclude potentially dysfunctional livers. The exclusion criteria included the following: severe macrovesicular steatosis, ischemic necrosis, prominent chronic portal inflammation, prominent periductular fibrosis, granulomatous inflammation, bridging fibrosis, and malignancy. Twenty-seven of the 385 donor livers examined were excluded before transplantation. The following histologic features were present in the excluded livers: severe steatosis (22), ischemic necrosis (2), portal inflammation (1), and periductular fibrosis (2). Steatosis was present in 51 of the 385 (13.25%) organs examined, including 22 of the donor organs excluded before transplantation. Twenty-nine livers with mild to moderate steatosis were implanted into size and blood type-matched recipients. Indicators of allograft function (prothrombin time and bilirubin) and damage (aspartate aminotransferase and alanine aminotransferase) were measured daily for the first 10 days after transplant. There was no statistically significant difference between the group of nonfat livers and donor livers containing mild steatosis. Statistically significant higher posttransplant serum alanine aminotransferase and prothrombin time levels were present in the patients with livers implanted with mild versus moderate steatosis. The 1-year survival rate for patients receiving fatty versus nonfatty donor livers was not statistically different (Kaplan-Meier, P = 0.592). No significant differences were found in the clinical and laboratory characteristics of donors whose organs were implanted compared with the clinical and laboratory characteristics of donors whose organs were excluded. The primary nonfunction rate after applying the exclusion criteria was 1.4%, which is a significant decrease compared with our primary nonfunction rate of 8.5% before using frozen section examination. Frozen section examination is useful in excluding donor organs which may become dysfunctional after transplantation.

Suppression of HLA-specific Alloantibodies by High-Dose Intravenous Immunoglobulins (IVIg). A Potential Tool for Transplantation of Immunized Patients

Abstract: Renal transplantation in patients presenting end-stage renal failure can be hampered by the presence of alloantibodies against HLA antigens. In 4 out of 5 patients with HLA-specific alloantibodies waiting for a renal allograft, treatment with high-dose i.v. Ig resulted in a prolonged suppression (over 3 months) of most of the panel-reactive anti-HLA antibodies (PRA). Intravenous polyclonal human Ig (IVIg) and F(ab')2 fragments from IVIg inhibited the binding of patients' plasma and IgG fractions to peripheral blood lymphocytes from normal donors as well as their cytotoxicity, suggesting that the in vivo effect of IVIg was mediated by the presence, in the IVIg preparation, of anti-idiotypes directed against idiotypes borne on the anti-HLA antibodies. Thus, treatment with IVIg can be a valuable tool toward the transplantation of immunized patients.

Factors influencing weight gain after renal transplantation.

Abstract: Weight gain following renal transplantation occurs frequently but has not been investigated quantitatively. A retrospective chart review of 115 adult renal transplant recipients was used to describe patterns of weight gain during the first 5 years after transplantation. Only 23 subjects (21%) were overweight before their transplant. Sixty-six subjects (57%) experienced a weight gain of greater than or equal to 10%, and 49 subjects (43%) were overweight according to Metropolitan relative weight criteria at 1 year after transplantation. There was an inverse correlation between advancing age and weight gain, with the youngest patients (18-29 years) having a 13.3% weight gain and the oldest patients (age greater than 50 years) having the lowest gain of 8.3% at 1 year (P = 0.047). Black recipients experienced a greater weight gain than whites during the first posttransplant year (14.6% vs. 9.0%; P = 0.043), and maintained or increased this difference over the 5-year period. Men and women experienced comparable weight gain during the first year (9.5% vs. 12.1%), but women continued to gain weight throughout the 5-year study (21.0% total weight gain). The men remained stable after the first year (10.8% total weight gain). Recipients who experienced at least a 10% weight gain also increased their serum cholesterol (mean 261 vs. 219) and triglyceride (mean 277 vs. 159) levels significantly, whereas those without weight gain did not. Weight gain did not correlate with cumulative steroid dose, donor source (living-related versus cadaver), rejection history, pre-existing obesity, the number of months on dialysis before transplantation, or posttransplant renal function. Posttransplant weight gain is related mainly to demographic factors, not to treatment factors associated with the transplant. The average weight gain during the first year after renal transplantation is approximately 10%. This increased weight, coupled with changes in lipid metabolism, may be significant in terms of altering risk from cardiovascular morbidity.

Variation in expression of endothelial adhesion molecules in pretransplant and transplanted kidneys : correlation with intragraft events

Abstract: Endothelial adhesion molecules are directly involved in the localization and migration of leukocytes from the circulation into tissues at sites of inflammation. We have compared the expression of PECAM-1 (CD31), ELAM-1, ICAM-1 (CD54), and VCAM-1 in pretransplant (n = 20) and needle-core biopsies from renal transplants obtained during different clinical circumstances (n = 42). PECAM-1 was consistently expressed on all endothelium in both pretransplant and transplant biopsies. In contrast, there was variation in endothelial expression of ELAM-1 and in proximal tubular expression of ICAM-1 and VCAM-1 between pretransplant biopsies. After transplantation induced expression of endothelial ELAM-1 and VCAM-1 and tubular induction of ICAM-1 and VCAM-1 was detected. Induced adhesion molecule expression was frequently associated with focal leukocyte infiltration, and there was a significantly higher level of CD45 and CD25 positive cell infiltration in biopsies with induced adhesion molecule expression. The induction of adhesion molecule expression is evidence of endothelial activation in these transplant biopsies. Comparison of adhesion molecule expression and HLA-class II antigen expression revealed that induced tubular class II antigens may be detected in the absence of induced adhesion molecule expression.

Induction of long-term specific tolerance to allografts in rats by therapy with an anti-CD3-like monoclonal antibody.

Abstract: Monoclonal antibodies to CD3 have been shown to activate T cells in vivo and in vitro but have also been shown to render T cells anergic in vitro. In this study G4.18, a mouse IgG3 mAb, was produced that appeared to recognize CD3 by its binding to all peripheral T cells, including a population not recognized by mAb to TCR-alpha/beta that was presumed to be TCR-gamma/delta cells. It precipitated molecules in the 24-26 kd region consistent with the CD3 complex as well as molecules approximately 45 and approximately 49 kd that corresponded to TCR alpha and beta chains and a 92-kd complex. Incubating T cells for 24 hr with saturating concentrations of G4.18 caused modulation of the TCR complex. In vitro, it activated T cells but only if prebound to plastic. In solution it inhibited MLC and CML, but not PHA or Con A activation. In vivo, G4.18 was not toxic even in high doses, and this was thought to be due to the inability of this mAb to activate T cells in vitro because the rat lacks Fc receptors for mouse IgG3. Therapy with G4.18 resulted in transient modulation of TCR/CD3 on T cells and depletion of these cells from blood. G4.18 had no depleting effects by lymph node or spleen cells but caused marked, transient thymic involution. Therapy with G4.18 also induced indefinite survival (> 100 days) of PVG (RTIc) heart grafts but not skin grafts in DA (RTIa) hosts. These hosts with long-surviving cardiac transplants, when grafted from PVG skin, accepted these grafts but rejected third-party skin in first-set. Thus G4.18 was shown to induce long-term specific tolerance to an organ allograft.

Hamster-to-rat heart and liver xenotransplantation with FK506 plus antiproliferative drugs.

Abstract: Heterotopic hamster hearts transplanted to unmodified LEW rats underwent humoral rejection in 3 days. Survival was prolonged to a median of 4 days with 2 mg/kg/day FK506. As monotherapy, 15 mg/kg/day cyclophosphamide greatly prolonged graft survival--far more than could be accomplished with RS-61443, brequinar (BQR), mizoribine, methotrexate, or deoxyspergualin. However, when FK506 treatment, which was ineffective alone, was combined with a short induction course (14 or 30 days) of subtherapeutic BQR, RS-61443, or cyclophosphamide, routine survival of heart xenografts was possible for as long as the daily FK506 was continued. In addition, a single large dose of 80 mg/kg cyclophosphamide 10 days preoperatively allowed routine cardiac xenograft survival under FK506. The ability of these antimetabolites to unmask the therapeutic potential of FK506 correlated, although imperfectly, with the prevention of rises of preformed heterospecific cytotoxic antibodies immediately postoperatively. As an adjunct to FK506, azathioprine was of marginal value, whereas mizoribine, methotrexate, and deoxyspergualin (DSPG) were of intermediate efficacy. After orthotopic hepatic xenotransplantation, the perioperative survival of the liver with its well-known resistance to antibodies was less dependent than the heart on the antimetabolite component of the combined drug therapy, but the unsatisfactory results with monotherapy of FK506, BQR, RS-61443, or cyclophosphamide were changed to routine success by combining continuous FK506 with a short course of any of the other drugs. Thus, by breaking down the antibody barrier to xenotransplantation with these so-called antiproliferative drugs, it has been possible with FK506 to transplant heart and liver xenografts with consistent long-term survival of healthy recipients.

Enzyme-linked immunoassay for anti-HLA antibodies--an alternative to panel studies by lymphocytotoxicity.

Abstract: In order to provide a simple and specific assay for the detection and quantitation of IgG and IgM anti-HLA antibodies in sera, HLA antigens purified from a pool of 240 random donor platelets were used to develop a solid-phase enzyme-linked immunoassay (EIA). The reference values for identifying the presence of IgG or IgM anti-HLA antibodies were determined by assaying sera from 39 healthy individuals without prior HLA alloimmunization. The assay was evaluated by studying sera from 122 patients who had been characterized previously for panel reactive antibodies by the lymphocytotoxicity assay (LCA). A significant linear correlation between two assays was noted (r = 0.8, P = 0.0001). Further analyses of the data demonstrated that the newly developed EIA has 100% specificity and 95.3% sensitivity as compared with the LCA. Additional studies revealed that patients whose PRA increased or decreased over time were in parallel with antibody levels measured by EIA. When the EIA was used to measure anti-HLA antibody titers, it was more sensitive than the LCA. Since the EIA is sensitive, specific, and technically less demanding, it should provide an useful alternative to reduce the number of the more laborious panel studies for monitoring anti-HLA antibody status in candidates for organ transplantation and recipients of blood transfusions.

Improved results of living-related liver transplantation with routine application in a pediatric program.

Abstract: Living related liver transplantation (LRT) was introduced as a response to the shortage of donor organs that has existed for small children. Results were promising in the initial experience, with a one-year patient survival of 80% and a graft survival of 76%. Since the completion of the protocol, LRT has been considered routinely in the management of children in our center. We present here our experience with 45 consecutive transplants in which LRT accounts for 40% of grafts with an overall patient survival of 90%. Between 4/91 and 4/92, 46 OLT were performed in 41 children. Median age was 2.7 years (3 months to 13 years) and weight was 10.4 kg (3.6-60 kg). Thirty-five were primary grafts, 10 were retransplants

Systemic and renal hemodynamic differences between fk506 and cyclosporine in liver transplant recipients

Abstract: Immunosuppression after transplantation is complicated by hypertension and nephrotoxicity, reflecting widespread vasoconstriction associated with CsA. FK506 is a novel alternative immunosuppressive agent, structurally unrelated to CsA. These studies compared systemic and renal vascular changes developing in the initial 4 weeks after liver transplantation in patients treated with FK506 (plus PRED) and CsA (plus PRED and AZA). We studied arterial pressure, cardiac index (pulsed doppler ultrasound), and systemic resistance index (SVRI) before and weekly after liver transplant in 32 patients treated with CsA (2 mg/kg initial dose plus PRED; median dose at week 4, 30 mg/day) and 14 patients treated with FK506 (0.15 mg/kg/day initial dose and PRED; mean week 4 dose, 12.5). Renal plasma flow and glomerular filtration rate (GFR) were measured by clearance of para-amino hippurate and 125-iothalamate. Renin activity, aldosterone, and urinary prostanoids were measured by RIA. Pretransplant pressures and hemodynamics reflected low SVRI and increased cardiac index typical of end-stage liver disease. After transplantation, SVRI and pressures rose in both groups, but after week 2, SVRI was lower in patients treated with FK506. This was associated with less prevalent clinical hypertension during the subsequent 4 months (4/14 FK506 (28%) vs. 25/32 (78%) CsA, P < 0.01). By contrast, renal blood flow and GFR fell in both treatment groups similarly, whereas renal vascular resistance rose. Urinary 6-keto-PG-F1-alpha was suppressed in all transplant recipients, but to a greater degree in FK506-treated patients. This value correlated directly to post-transplant GFR (r = 0.48, P < 0.001). These data indicate that FK506-based immunosuppression differs from CsA by inducing less systemic vasoconstriction and hypertension. Renal vasoconstrictive effects were at least as great as those seen with CsA, however, and indicate that nephrotoxicity will remain a common feature to both regimens.

Distribution of cell adhesion molecules (ICAM-1, VCAM-1, ELAM-1) in renal tissue during allograft rejection.

Abstract: The tissue distribution of cellular adhesion molecules (CAMs) was studied in specimens from 10 normal human kidneys and in 52 biopsies from kidney allografts with cell-mediated rejection. In addition to the vascular presence of ICAM-1, a common finding in normal kidneys, expression of ICAM-1 on tubular cells was observed in 22 graft biopsies. Compared with normal kidneys, where VCAM-1 was present on Bowman's capsules and few proximal tubular cells, a markedly enhanced expression of VCAM-1 in numerous tubuli (including distal tubular segments) was observed in 51 graft biopsies. In 41 graft specimens VCAM-1 appeared also in variable numbers of peritubular capillaries. Infiltrating leukocytes carrying VCAM-1 were observed in 7 grafts. ELAM-1 could not be found in normal kidneys but was restricted to some peritubular capillaries in 29 grafts. Comparable results were obtained with cultured renal tubular cells when stimulated by TNF-alpha. That the induced appearance of adhesion molecules was in fact related to actual cellular synthesis was demonstrated by Northern blot analysis. Thus, little ICAM-1 specific mRNA of 3.4-kb length could be detected in unstimulated cultured renal tubular cells, but hybridization was markedly increased after stimulation with TNF-alpha. A substantial amount of VCAM-1 specific mRNA of 3.2-kb length was present already in unstimulated renal tubular cells. Likewise, synthesis of VCAM-1 mRNA was enhanced by stimulation with TNF-alpha. TNF-stimulated endothelial cells also showed weak synthesis of VCAM-1 mRNA. The results provide further evidence that constitutive and inducible expression of cell adhesion molecules contributes to the process of allograft rejection.