The effect of Share 35 on biliary complications: An interrupted time series analysis.

The purpose of the Share 35 allocation policy was to improve liver transplant waitlist mortality, targeting high MELD waitlisted patients. However, policy changes may also have unintended consequences that must be balanced with the primary desired outcome. We performed an interrupted time series assessing the impact of Share 35 on biliary complications in a select national liver transplant population using the Vizient CDB/RM database. Liver transplants that occurred between October 2012 and September 2015 were included. There was a significant change in the incident-rate of biliary complications between Pre-Share 35 (n = 3018) and Post-Share 35 (n = 9984) cohorts over time (P = .023, r2  = .44). As a control, a subanalysis was performed throughout the same time period in Region 9 transplant centers, where a broad sharing agreement had previously been implemented. In the subanalysis, there was no change in the incident-rate of biliary complications between the two time periods. Length of stay and mean direct cost demonstrated a change after implementation of Share 35, although they did not meet statistical difference. While the target of improved waitlist mortality is of utmost importance for the equitable allocation of organs, unintended consequences of policy changes should be studied for a full assessment of a policy's impact.

The Current State of Liver Transplantation in the United States: Perspective From American Society of Transplant Surgeons (ASTS) Scientific Studies Committee and Endorsed by ASTS Council.

This article is a review of the salient points and a future prospective based on the 2014 Organ Procurement and Transplantation Network (OPTN)/Scientific Registry of Transplant Recipients (SRTR) liver donation and transplantation data report recently published by the American Journal of Transplantation. Emphasis of our commentary and interpretation is placed on data relating to waitlist dynamics, organ utilization rates, the impact of recent advances in the treatment of hepatitis C, and the increases in end-stage renal disease among liver transplant candidates. Finally, we share our vision on potential areas of innovation that are likely to significantly improve the field of liver transplantation in the near future.

Improving transplant patient safety through pharmacist discharge medication reconciliation.

Greater than 50% of medication errors are estimated to occur during transitions of care, and solid-organ transplant recipients are at an increased risk for errors due to significant changes in their medication regimen following transplantation. This prospective, observational study with a historical control group was conducted to evaluate the discharge process for transplant recipients and determine if transplant pharmacist involvement would improve safety. During the prospective period, a total of 191 errors were made on discharge medication reconciliations (n = 64, mean rate 3.0 per patient); however, pharmacists prevented 119 of these errors (1.9 errors per patient). In the retrospective period, none of the 430 errors identified were prevented at the time of discharge (n = 128, p < 0.0001). The 72 errors not prevented at the time of discharge in the prospective cohort were identified by the pharmacist at the patient's first clinic visit (1.1 errors per patient). In the historical cohort, all 430 errors made at discharge persisted until at least the time of the first clinic visit (3.4 errors per patient, p < 0.0001). This study demonstrates that transplant recipients are at a high risk for medication errors and that transplant pharmacist involvement leads to improved safety through the significant reduction of medication errors.

Renal function at two years in liver transplant patients receiving everolimus: results of a randomized, multicenter study.

In a 24-month prospective, randomized, multicenter, open-label study, de novo liver transplant patients were randomized at 30 days to everolimus (EVR) + Reduced tacrolimus (TAC; n = 245), TAC Control (n = 243) or TAC Elimination (n = 231). Randomization to TAC Elimination was stopped prematurely due to a significantly higher rate of treated biopsy-proven acute rejection (tBPAR). The incidence of the primary efficacy endpoint, composite efficacy failure rate of tBPAR, graft loss or death postrandomization was similar with EVR + Reduced TAC (10.3%) or TAC Control (12.5%) at month 24 (difference -2.2%, 97.5% confidence interval [CI] -8.8%, 4.4%). BPAR was less frequent in the EVR + Reduced TAC group (6.1% vs. 13.3% in TAC Control, p = 0.010). Adjusted change in estimated glomerular filtration rate (eGFR) from randomization to month 24 was superior with EVR + Reduced TAC versus TAC Control: difference 6.7 mL/min/1.73 m(2) (97.5% CI 1.9, 11.4 mL/min/1.73 m(2), p = 0.002). Among patients who remained on treatment, mean (SD) eGFR at month 24 was 77.6 (26.5) mL/min/1.73 m(2) in the EVR + Reduced TAC group and 66.1 (19.3) mL/min/1.73 m(2) in the TAC Control group (p < 0.001). Study medication was discontinued due to adverse events in 28.6% of EVR + Reduced TAC and 18.2% of TAC Control patients. Early introduction of everolimus with reduced-exposure tacrolimus at 1 month after liver transplantation provided a significant and clinically relevant benefit for renal function at 2 years posttransplant.

Everolimus with reduced tacrolimus improves renal function in de novo liver transplant recipients: a randomized controlled trial.

In a prospective, multicenter, open-label study, de novo liver transplant patients were randomized at day 30±5 to (i) everolimus initiation with tacrolimus elimination (TAC Elimination) (ii) everolimus initiation with reduced-exposure tacrolimus (EVR+Reduced TAC) or (iii) standard-exposure tacrolimus (TAC Control). Randomization to TAC Elimination was terminated prematurely due to a higher rate of treated biopsy-proven acute rejection (tBPAR). EVR+Reduced TAC was noninferior to TAC Control for the primary efficacy endpoint (tBPAR, graft loss or death at 12 months posttransplantation): 6.7% versus 9.7% (-3.0%; 95% CI -8.7, 2.6%; p<0.001 for noninferiority [12% margin]). tBPAR occurred in 2.9% of EVR+Reduced TAC patients versus 7.0% of TAC Controls (p = 0.035). The change in adjusted estimated GFR from randomization to month 12 was superior with EVR+Reduced TAC versus TAC Control (difference 8.50 mL/min/1.73 m(2) , 97.5% CI 3.74, 13.27 mL/min/1.73 m(2) , p<0.001 for superiority). Drug discontinuation for adverse events occurred in 25.7% of EVR+Reduced TAC and 14.1% of TAC Controls (relative risk 1.82, 95% CI 1.25, 2.66). Relative risk of serious infections between the EVR+Reduced TAC group versus TAC Controls was 1.76 (95% CI 1.03, 3.00). Everolimus facilitates early tacrolimus minimization with comparable efficacy and superior renal function, compared to a standard tacrolimus exposure regimen 12 months after liver transplantation.

A critical analysis of racial difference with mycophenolate mofetil (MMF) dosing, clinical outcomes and adverse effects in pediatric kidney transplant patients.

There is paucity in the data examining the differences in mycophenolate mofetil (MMF) dosing and outcomes among pediatric kidney transplant recipients (PKTX) between races. The aims of this study were as follows (i) to assess whether higher doses of MMF are being utilized in African American (AA) PKTX (ii) to determine whether there is a correlation between MMF dose and outcomes between races, and (iii) to assess the adverse effects of MMF between races. This study analyzed 109 PKTX who received MMF between 7/99 and 5/08. Demographics were similar between groups. Fewer AAs received kidneys from living donors (18% vs. 44%), spent more time on dialysis (1.0 vs. 0.5 yr), and had more human leukocyte antigen mismatches (4 vs. 3). MMF doses among AA patients were higher throughout the study, with statistical differences at week 4, month 3, and month 18. AA patients had significantly higher acute rejection rates and trended toward poorer graft survival; infections, adverse events from MMF and post-transplant lymphoproliferative disease tended to be lower in the AA patients. AA PKTX received higher MMF doses within the first three yr post-transplant compared to their non-AA counterparts, yet demonstrate significantly more acute rejection episodes. Importantly, MMF caused fewer adverse events in AA patients, despite these patients receiving higher doses.

Combining ALT/AST Values with Surgical APGAR Score Improves Prediction of Major Complications after Hepatectomy.

Hepatectomy is a complex procedure with high morbidity and mortality. Early prediction/prevention of major complications is highly valuable for patient care. Surgical APGAR score (SAS) has been validated to predict post-surgical complications (PCs). We aimed to define a simple complications classification following hepatectomy based on a therapy-oriented severity Clavien-Dindo classification (CDC). 119 patients undergoing liver resection were included. PCs were determined at follow-up based on CDC. Clinicopathological factors were used to calculate SAS. A receiver-operator characteristic (ROC) curve analysis estimated the predictive value of SAS for PCs. Circulating markers levels of liver injury were analyzed as critical elements on PCs. SAS (P=0.008), estimated blood-loss (P=0.018) and operation time (P=0.0008) were associated with PCs. SAS was reduced in patients with (+) compared to those without (-) complications (6.64±1.84 vs 5.70±1.79, P=0.0079). The area-under-the-curve was 0.646 by ROC, indicating an acceptable discrimination with 65% possibility to distinguish (-) and (+) groups (P=0.004). Best cutoff value for SAS was ≤6/≥7, at which sensitivity and specificity were maximal. ALT/ASL levels were significantly different within the group with 9-10 SAS points (P=0.01 and 0.02). In conclusion, SAS provides accurate risk stratification for major PCs after hepatectomy, and might help improving the overall patient outcome.

Anti-CD2 receptor and anti-CD2 ligand (CD48) antibodies synergize to prolong allograft survival.

Indefinite graft survival was obtained with murine cardiac allografts using the combined administration of monoclonal antibodies (mAbs) directed against the receptor ligand pair CD2-CD48. Although each antibody could prolong graft survival when given alone, neither resulted in the indefinite graft survival seen with the combination. Combined mAb administration is associated with inhibition of T cell priming and help and subsequent cytotoxic T lymphocyte generation. This indicates that the interaction between CD2 and its ligand is important for antigen priming and recognition, and combined mAbs may prove to be a useful therapeutic regimen for transplantation.

The use of drotrecogin alfa (activated) in solid organ transplant patients: a case series.

BACKGROUND: Drotrecogin alfa (activated) (DAA), a recombinant human activated protein C, is indicated for the reduction of mortality in patients with severe sepsis who have a high risk of death. In the initial trial, DAA demonstrated a significant reduction in mortality at 28 days for patients treated with DAA in comparison with standard supportive treatment (placebo). However, solid organ transplant recipients were excluded from the study. Transplant recipients are at an increased risk for sepsis and there is minimal literature describing the safety and efficacy of DAA in the transplant population. METHODS: Thirteen solid organ transplant recipients who received DAA between November 2001 and January 2004 were included in this case series. Patients were prospectively identified and data collection occurred concurrently and by retrospective chart review. All patients met the DAA use criteria based on the institutional standard protocol. RESULTS: We report the outcomes of the 13 adult transplant patients who received a total of 14 courses of DAA for severe sepsis. At the time of DAA initiation, all patients required mechanical ventilation, 86% necessitated vasopressor support, and had a median of 3 dysfunctional organs. The median Acute Physiology and Chronic Health Evaluation (APACHE) II score at initiation was 30. Overall, hemodynamic stability and APACHE II score improved at the end of DAA infusion. Causes of early discontinuation were bleeding (57%), scheduled procedure (14%), increased international normalized ratio (14%), and death (14%). In-hospital, 28-day, and 1-year mortality was 69%, 62%, and 83%, respectively. CONCLUSION: DAA appears to be safe with appropriate monitoring. However, transplant recipients had a higher incidence of bleeding events leading to early discontinuation of DAA. Efficacy is difficult to assess without an appropriate control group for comparison.

C-Jun N-terminal kinase 2 promotes graft injury via the mitochondrial permeability transition after mouse liver transplantation.

The c-Jun N-terminal kinase (JNK) pathway enhances graft injury after liver transplantation (LT). We hypothesized that the JNK2 isoform promotes graft injury via the mitochondrial permeability transition (MPT). Livers of C57BL/6J (wild-type, WT) and JNK2 knockout (KO) mice were transplanted into WT recipients after 30 h of cold storage in UW solution. Injury after implantation was assessed by serum ALT, histological necrosis, TUNEL, Caspase 3 activity, 30-day survival, and cytochrome c and 4-hydroxynonenal immunostaining. Multiphoton microscopy after LT monitored mitochondrial membrane potential in vivo. After LT, ALT increased three times more in WT compared to KO (p < 0.05). Necrosis and TUNEL were more than two times greater in WT than KO (p < 0.05). Immunostaining showed a >80% decrease of mitochondrial cytochrome c release in KO compared to WT (p < 0.01). Lipid peroxidation was similarly decreased. Every KO graft but one survived longer than all WT grafts (p < 0.05, Kaplan-Meier). After LT, depolarization of mitochondria occurred in 73% of WT hepatocytes, which decreased to 28% in KO (p < 0.05). In conclusion, donor JNK2 promotes injury after mouse LT via the MPT. MPT inhibition using specific JNK2 inhibitors may be useful in protecting grafts against adverse outcomes from ischemia/reperfusion injury.

Long-term efficacy of induction therapy with anti-interleukin-2 receptor antibodies or thymoglobulin compared with no induction therapy in renal transplantation.

BACKGROUND: Although the utility of antibody induction therapy has been demonstrated in clinical trials, the ideal regimen to use based on patient risk factors has not been fully elucidated. The objectives of this study were to determine the impact of either anti-interleukin-2 receptor antibodies (IL-2RA) or thymoglobulin induction therapies versus no induction therapy on acute rejection rates and on 3-year graft survival rates. METHODS: This retrospective analysis compared 3 patient groups-those who did not receive induction, those who received IL-2RA induction, and those who received thymoglobulin induction. RESULTS: Three hundred eleven patients were included in this study. Patients were well matched for demographic and immunologic characteristics in the noninduced and IL-2RA induction therapy groups; the thymoglobulin induction group included significantly higher risk patients. The acute rejection rates were significantly lower in the IL-2RA and thymoglobulin groups when compared with the no induction therapy group (28% vs 15% vs 41%, respectively; P = .001), which was confirmed with multivariate analysis. The 3-year graft loss rates (no induction 21% vs IL2-RA induction 19% vs thymoglobulin induction 25%; P > .50) and creatinine concentrations (no induction 1.8 +/- 0.7, IL-2RA induction 2.0 +/- 1.0, and thymoglobulin induction 1.9 +/- 1.2; P = .47) were similar between all groups. CONCLUSION: The use of induction therapy significantly reduces the incidence of acute rejection. The use of thymoglobulin induction equalizes 3-year graft survival rates in high-risk patients to those seen in low-risk patients receiving either no induction or IL-2RA induction.

Can family attributes explain the racial disparity in living kidney donation?

BACKGROUND: Living donation is a safe, effective treatment for patients with end-stage renal disease (ESRD), yet rates of live kidney donation remain low. Potential transplant recipients may be more inclined to ask a family member for a living donation if they feel familial closeness. METHODS: The FACES II and the Living Organ Donor Survey were administered to patients attending pretransplant education to assess individual perceptions of family structure and willingness to request a living kidney donation from a family member. RESULTS: A total of 328 potential transplant recipients were included in the study: 200 (61%) African American and 128 (39%) Caucasian. Approximately half were willing to ask for a living donation. Individual's perception of family cohesion, adaptability, and type as measured by FACES II showed most families were mid-range with optimal cohesion and adaptability. Family cohesion and adaptability showed no association with being willing to request a live donation, but those single/never married were only half as likely to ask for donation (odds Ratio [OR] 0.51; 95% confidence interval [CI] 0.31-0.86, P = .01). Lower education (beta = -0.49) and unmarried status (beta = -0.31) predicted a lower cohesion score. CONCLUSION: Family type, cohesion, and adaptability showed no differences across race and was not related to the potential recipient's willingness to ask for a live donation. Although responses by race did not differ, an important finding showed that only half of ESRD patients are willing to ask for a live organ donation, and those patients that were single/never married were less likely to ask for a living donation. Research surrounding this reluctance is warranted.

Clinical outcomes and costs associated with in-hospital biliary complications after liver transplantation: a cross-sectional analysis.

INTRODUCTION: In-hospital biliary complications (BCs) after liver transplantation (LT) are reported in up to 20 % of patients and contribute to poor outcomes and increased costs. Existing single-center outcome and cost analyses studies are limited in scope. METHODS: This is a cross-sectional analysis of national data involving 7,967 patients transplanted between 2011 and 2012 with the primary aim of determining the association between BCs and clinical outcomes and costs. Age, race, diagnosis, and severity of illness are associated with the development of BCs. RESULTS: BCs develop in 14.6 % of LT recipients and have substantial implications for perioperative outcomes, including length of hospital and ICU stay (27.9 vs 19.6 mean days, p < 0.001 and 12.0 vs 8.3 mean days, p < 0.001, respectively), in-hospital morbidity (39 vs 27 %, p < 0.001), 30-day readmissions (14.8 vs 11.2 %, p < 0.001), and in-hospital mortality (5.8 vs 4.0 %, p < 0.001). BCs contributed to a mean increase in in-hospital costs of $36,212 (p < 0.001), due to increases in accommodations ($9,539, p < 0.001), surgical services ($3,988, p < 0.001), and pharmacy services ($8,445, p < 0.001). DISCUSSION: BCs are a predominant etiology for in-hospital morbidity and mortality, while contributing significantly to the high cost of LT. Efforts should be focused on understanding salient and modifiable risk factors, while developing innovative strategies to reduce BCs.

Production of multiple murine CD2 receptor constructs using the baculovirus expression vector and a rapid dot-blot assay.

The baculovirus expression system was used to produce three different constructs of the murine cell surface adhesion receptor CD2. One construct coded for a single, N-terminal, Ig-fold domain. It was inefficiently secreted and therefore primarily intracellular. The second construct coded for both extracellular, N-terminal Ig-fold domains. This was efficiently secreted into culture supernatant. The third construct coded for the full-length transmembrane molecule which localized to the cell surface. All constructs were monomers of predicted MWr and were appropriately glycosylated. They retained epitopic specificity as demonstrated by binding to mAbs, and adhesion function as demonstrated by a rosetting assay.

Prolongation of allograft and xenograft survival in mice by anti-CD2 monoclonal antibodies.

Anti-CD2 monoclonal antibodies (mAb) were used to influence graft survival in two transplantation models. Xenogeneic rat islets were transplanted intraportally into mice. Anti-CD2 mAb prolonged xenograft survival and was synergistic with UVB irradiation in prolonging survival. Anti-CD2 mAb was also more potent than an anti-CD4 mAb in this model. Allogeneic cardiac grafts were transplanted across an entire H-2 difference and anti-CD2 mAb prolonged allograft survival in a dose-dependent fashion. Kinetic experiments revealed that anti-CD2 mAb was most potent when administered at the time of allografting. A delay in administration of mAb markedly reduced its immunosuppressive effects. Furthermore, additional doses of mAb given after the initial doses provided no increased immunosuppression and anti-CD2 mAbs did not delay rejection of second-set allografts. These findings support the notion that anti-CD2 mAbs interfere with afferent immunity and that CD2 is most important during the initial steps of an immune response. Investigation of the effect of anti-CD2 mAb on cellular immune functions demonstrated, in agreement with previous results, that it caused antigenic down-modulation of CD2 with relative sparing of CD3, CD4, and CD8 cell surface expression. Concomitantly the MLR, CTL, and NK responses were suppressed.

Anti-CD2 and anti-CD3 monoclonal antibodies synergize to prolong allograft survival with decreased side effects.

Anti-CD3 monoclonal antibody suppresses immunity and prolongs allograft survival; however, it induces T cell activation and overproduction of soluble factors that result in a deleterious cytokine syndrome. Anti-CD2 mAb also prolongs allograft survival, by suppression of mature and precursor CD4 and CD8 T cells and NK cells, without an associated cytokine release. Because of the close physical and functional association of CD2 and CD3 on the T cell surface, we tested whether alpha CD2 mAb in combination with alpha CD3 mAb could act synergistically to prolong allograft survival, and whether the combination would affect the alpha CD3-associated cytokine syndrome. C57BL/6 (H-2b) hearts were transplanted to CBA (H-2k) recipients in a heterotopic nonvascularized model. Recipients received alpha CD2 (12-15) or alpha CD3 (145-2C11) mAb i.v. alone or in combination. Lymphocytes from treated animals were also analyzed by fluorescent flow cytometry and stimulated in vitro and assessed for proliferation and lymphokine production. Anti-CD2 and alpha CD3 each prolong allograft survival (mean survival time 22.4 +/- 1.0 and 27.4 +/- 3.3 days, respectively vs. 14.0 +/- 0.6 for control mAb, P < 0.001 for both vs. control). Combinations of mAbs show a more complicated interaction. Very low doses (1 microgram) of alpha CD2 and alpha CD3, which have no effect when given alone, are synergistic (16.5 +/- 1.3 days, P < 0.02). A high dose of alpha CD2 (100 micrograms), which is immunosuppressive, is additive with a moderate dose of alpha CD3 (10 micrograms), which is immunostimulatory. The two mAbs are again synergistic when a high dose of alpha CD2 (100 micrograms) is combined with a high dose of alpha CD3 (1 mg) (> 51.5 +/- 23.0 days, P < 0.001). Furthermore, high-dose alpha CD2 administered 48 h prior to high-dose alpha CD3 was a more effective combination for prolonging allograft survival than both antibodies administered simultaneously (67.1 +/- 10 vs. 35.8 +/- 0.7 days, P < 0.05). Anti-CD2 also diminishes the alpha CD3-associated cytokine syndrome, and prior in vivo treatment with alpha CD2 decreases the subsequent in vitro proliferative response to alpha CD3 and the alpha CD3-stimulated production of IL-2 and IL-4. Flow cytometry demonstrates that in general these mAbs do not deplete but leave T cell populations intact with altered receptor expression. These results show that the combination of alpha CD2 and alpha CD3 mAbs prolongs cardiac allograft survival in a synergistic fashion while decreasing the side effects of alpha CD3 mAb alone.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-CD2 monoclonal antibodies synergize with FK506 but not with cyclosporine or rapamycin to induce tolerance.

CsA, FK506, and rapamycin prolong allograft survival; however, each has significant associated side effects at therapeutic doses. Anti-CD2 mAbs also prolong survival but without toxicity. We tested whether alpha CD2 mAbs in combination with subtherapeutic immunosuppression could prolong allograft survival in a synergistic fashion. C57BL/6 (H-2b) mouse hearts were transplanted to CBA (H-2k) mice in a heterotopic, non-vascularized cardiac allograft model. Recipients received immunosuppressants intraperitoneally for 14 days and/or alpha CD2 mAb intravenously for 2 days starting at the time of grafting. Survival was determined by electrocardiogram monitoring. Anti-CD2 alone prolonged survival to 22.4 +/- 1.0 days versus 13.4 +/- 0.5 days for untreated controls (P < 0.05), while low dose FK506 minimally prolonged survival to 16.7 +/- 0.7 days (P < 0.057). However, FK506 plus alpha CD2 resulted in synergistic prolongation of graft survival to 28.0 +/- 2.1 days. Several doses of CsA and rapamycin in combination with alpha CD2 did not prolong survival over alpha CD2 administered alone. A 60-day course of low dose FK506 plus alpha CD2 resulted in indefinite graft survival (> 165 days). These animals were tolerant since they accepted a second donor-specific graft. CTL and MLR activity in long-term recipients were normal to both donor-specific and third party alloantigen. The combination of alpha CD2 with low dose FK506 is synergistic in prolonging cardiac allograft survival, while combinations with CsA and rapamycin are not. Continuous administration of low dose FK506 plus alpha CD2 results in a state of tolerance. This suggests that FK506 acts at a different locus in allograft immunity compared with the other immunosuppressants and this may be related to the alternative CD2 T cell activation pathway.

T-cell alterations in cardiac allograft recipients after B7 (CD80 and CD86) blockade.

BACKGROUND: T-cell activation requires engagement of the T cell receptor with the antigen-MHC and simultaneous ligation of the coreceptor CD28. CD28 binds both the CD80 (B7-1) and CD86 (B7-2) ligands on antigen-presenting cells. The functional role of these costimulatory pathways in transplantation is not completely understood. We tested the hypothesis that in vivo blockade of the CD28 pathway via the anti-CD80 and anti-CD86 monoclonal antibodies (mAbs) would prolong allograft survival. METHODS: Neonatal C57BL/6J (H2b) hearts were transplanted to CBA/J (H2k) recipients in a heterotopic nonvascularized model, with anti-CD80 and/or anti-CD86 mAbs being administered intravenously at the time of allografting (day 0) and on the following day (day 1). RESULTS: Anti-CD80 mAb (29.8+/-1.5 days) and anti-CD86 mAb (30.8+/-0.5 days) alone significantly prolonged allograft survival compared with the isotype control (10.7+/-0.4 days, P < 0.01, Wilcoxon rank sum). The concurrent (days 0 and 1) and sequential administration of anti-CD86 mAb on days 0 and 1 plus anti-CD80 mAb on days 2 and 3 prolonged allograft survival to >80 days. Simultaneous administration of anti-CD80 and anti-CD86 mAbs significantly suppressed donor-specific cytotoxic T lymphocyte responses to alloantigen. Anti-CD86 mAb suppressed intragraft interleukin (IL)-4, IL-10, IL-12 p40, and IL-15 mRNA expression. CONCLUSIONS: Anti-CD80 and/or anti-CD86 mAbs are potent immunosuppressants in prolonging allograft survival. Combined blockade of the B7 (CD80 and CD86) ligands seems to be the most effective in prolonging allograft survival and suppressing donor-specific allogeneic cytotoxic T lymphocyte responses. In vivo blockade of CD86, in comparison to CD80, had the greatest immunosuppressive effect on day 7 intragraft cytokines, suggesting its role on early allogeneic immune responses.