Clinical Signs Of Rejection Research Articles

(345) - Allosensitized Cardiac Transplant Recipients Treated with CD38-Antibody Daratumumab Show Histomorphologic Signs of PAMR in Biopsies without Clinical Signs of Rejection

(345) - Allosensitized Cardiac Transplant Recipients Treated with CD38-Antibody Daratumumab Show Histomorphologic Signs of PAMR in Biopsies without Clinical Signs of Rejection

Correlation between facial vascularized composite allotransplantation rejection and laboratory markers: Insights from a retrospective study of eight patients

The field of facial vascularized composite allotransplantation (fVCA) is still new and a limited number of patients have undergone the procedure. This has led to a lack of understanding about the impact of fVCA rejection on standard laboratory markers (e.g., CBC, BMP, CRP) for the acute management of these patients. It is not clear if rejection elicits a systemic inflammatory response that influences common inflammatory markers such as WBC and CRP. A comprehensive understanding of changes in these markers could help in the management of fVCA patients in the acute setting. The medical records of 8 fVCA patients with a total of 9 transplants were reviewed retrospectively, and data on standard laboratory values (CBC, BMP, LFTs, CRP) and vital signs were extracted. To examine the relationship between laboratory values and rejection status, linear mixed models were used to analyze the data, taking into account their longitudinal nature (repeated measures). A statistically significant relationship was found between the Banff grade of rejection and the relative number of basophils in the patient's blood during rejection (p=0.005). In addition, in patients with clinical signs of rejection (e.g., facial erythema, edema) and skin biopsy showing Banff ≥II, CRP was found to be significantly elevated (p=0.03). The WBC count remained stable during rejection, and the relative number of neutrophils was lower at the time of rejection, indicating possible consumption at the site of rejection. During fVCA rejection, most standard laboratory parameters and vital signs appear to be stable. However, the levels of CRP and basophils were elevated during rejection, while the neutrophil count was lower. Leukocytosis can likely be used as a marker of microbial infection in fVCA patients, as WBC does not seem to increase at the time of allograft rejection.

P2A.07: Mucosal T-cell kinetic in the early phases of rat model of allogenic small bowel transplantationMucosal T-cell kinetic in the early phases of rat model of allogenic small bowel transplantation

Introduction: Intestinal transplantation (IT) faces many challenges, among them, the necessity to early detect and treat rejection processes. Improving our understanding on the dynamics of allogenic response will be useful to bring candidate targets to these aims. The objective of our study was to determine the kinetics of mucosal T-cells population in the early phase of small bowel rejection using a Heterotopic IT rat model. We made emphasis in phenotypical, activation and exhaustion markers for the early detection of the rejection phenomena. Methods: Allogeneic heterotopic small bowel IT (n=5) was performed following standard procedure. Brown Norway animals were used as donors and Lewis as recipients. Rats did not receive any immune suppressor treatment. Rejection was monitored by clinical scoring and hematoxylin-eosin staining of intestinal grafts (Gf). T-cells from the peripheral blood (PB) and small bowel mucosa were assessed by flow cytometry. CD3, CD4, CD8, CD25, CD45, CD45RC, PD-1, FoxP3 and anti-Lewis MHC I expression was analyzed. Gf samples were taken at day 0, 3 and 7 post-operative (POD). Results: No clinical signs of rejection or significant histological changes were observed at day 3. At this time, in PB 7.9 % ± 0,7 of T cells were from the donor, meanwhile in the Gf 42,7% ± 4,6 of T-cells were recipient cells. We observed a significant increase of CD3+CD4+CD25+, CD3+CD4+CD45RC+ and CD3+CD8+CD45RC+ % in comparison with basal levels (PB:p<0,05;Gf:p<0,01). CD3+CD4+CD25+FoxP3+ cells were also increased in the Gf. At day 7 animals present significant weight loss and histological features compatible with mild to moderate cellular rejection. Differently from day 3 POD, in PB we could not detect donor T-cells. In the Gf 70% ± 7 of T-cells were from the recipient. CD3+CD4+CD45RC+ and CD3+CD8+CD45RC+ % were significantly higher than at day 3 POD (PB p<0,001;Gf:p<0,01). We detected increased levels of CD3+CD4+PD-1+ and CD3+CD8+PD-1+ cells in the Gf in comparison to basal levels(p<0,01). No differences in CD25 expression was observed between day 3 and 7. Conclusion: T-cell replacement in the Gf mucosa is a very fast process and CD25 expression in both PB and the Gf is an early event that precede the histological changes and should be analyzed as a potential biomarker. Considering that T-cells expressing CD45RC have been described as key players in the Gf rejection processes, our results also suggest they could be a relevant target to treat/prevent ACR.

Effects of esomeprazole and pantoprazole on renal function in stable kidney transplantation recipients: A randomized clinical trial.

Renal allograft survival requires the administration of multiple immunosuppressive drugs. This strategy may lead to gastric complications that necessitate gastro-protective medications, notably, proton pump inhibitors (PPIs). This study aimed to compare the effects of pantoprazole and esomeprazole on renal function in stable renal transplant recipients. A prospective, parallel, open-label clinical trial was performed with forty-seven adult renal transplant recipients receiving immunosuppressive therapy with cyclosporine (CSA) doses adjusted to attain trough concentrations of 100-150 µg/L, mycophenolate mofetil (MMF) at 750 mg q12 hr and prednisolone at 5 mg daily at Nasser Institute, Cairo, Egypt. The enrolled participants were randomized into two groups, which received either esomeprazole or pantoprazole at the same dose (40 mg once daily). Renal function was measured at baseline and monthly for 6 months. The study was conducted between January-September 2016. Main outcome measures clinical signs of rejection reflected by renal function decline, assessed by elevated levels of serum creatinine. The mean serum creatinine level was significantly lower in the sixth month than at baseline in esomeprazole group (p 0.004); interestingly there was a continuous decrease of serum creatinine levels in esomeprazole group and nearly constant values in pantoprazole group. There was no significant difference in serum creatinine levels between the two groups. From this study, it could be concluded that esomeprazole may be preferred over pantoprazole in renal transplant recipients because it decreased serum creatinine which is one of the markers of chronic allograft rejection in stable renal transplantation recipients.

Effect of Native Spleen Preservation in an Experimental Model of Modified Multivisceral Transplantation

Introduction Native spleen is usually removed in patients undergoing modified multivisceral transplantation (MMVT) increasing the risk of sepsis and graft-versus-host disease (GVHD). On the other hand, it has been reported that spleen preservation also increases the risk of allograft rejection. The mechanisms of theses effects including mixed chimerism level are poorly understood. Based on a novel experimental model of MMVT that triggers GVHD, we hypothesized that native spleen preservation attenuate GVHD after MMVT. Methods Isolated heterotopic intestinal transplantation (IT) or heterotopic MMVT from Lewis (LEW) to Brown Norway (BN) rats was performed. IT graft consisted in 80% of the small bowel, and MMVT graft consisted of the distal half of the stomach, duodenum, pancreas, spleen and the small bowel of the donor. The native spleen was removed (MVM-S) in half of the MMVT recipients (N=5), while the remaining preserved their own spleen (MVM+SP) (N=5). After MMVT or IT, the mixed hematopoietic chimerism was determined in peripheral blood samples by flow cytometry using strain-specific HLA antibodies and clinical signs of GVHD such as skin rash were evaluated. Results All animals in the group MVM-S presented clinical signs compatible with GVHD such as skin rash, weight loss, and diarrhea, among others, between 7 and 10 days after transplantation. Skin rash was particularly remarkable in the ears, snout and periocular area. Clinical signs of GVHD were less frequent in MVM-S and IT animals (100% vs 40% and 40%, p<0.05) Flow cytometry found that mixed chimerism was significantly higher in the MVM-S group, compared to the MVM+SP group (percentage donor’s lymphocytes in peripheral blood at 3 and 7 post-transplant days (PTD): 36,6% (30-53%) and 9,4% (3-18%) vs 23,6% (19-26%) and 20,5 (18-25,5%) respectively; p<0.05) (Figure 1). The level of chimerism gradually decreased as clinical signs of rejection appeared.Conclusion Allogeneic heterotopic MMVT in the strain combination L-BN yielded a higher rate of GVHD compared to IT. Native spleen preservation in MMVT recipients attenuated the occurrence of GVHD and reduced the level of chimerism compared to recipients that underwent spleen removal during the transplant. Further experimental studies are warranted to clarify the mechanisms of the spleen immune effects over GVHD, chimerism and rejection; however, the results shown in this work strongly support the importance of this organ in the field of intestinal transplantation.

THE EXPERIENCE OF PEDIATRIC HEART TRANSPLANTATION ON NORTH-WEST OF RUSSIAN FEDERATION

Aim:to estimate early and long-term outcomes in recipients under 18 years old who have been heart transplanted in Almazov National Medical Research Centre.Materials and methods. From April 2011 to September 2017 we performed 5 heart transplantations (HTx) in recipients under 18 years old (female) old) from adults donors. The median of age were 15 years (range 10–16 years), LVEF prior HTx – 17% (10–33%). Causes of heart failure were dilated cardiomyopathy (n = 2), non-compacted myocardium (n = 1), arrhythmogenic ventricular dysplasia (n = 1) and Ebstein’s anomaly (n = 1). They spent in HT waiting list 76 days (12–684 days). One patient underwent biventricular assist device Berlin Heart EXCOR implantation (days on support – 250) as a «bridge» to transplant. Due to coronary angiography (CAG) results 1 patient underwent HTx and CABG simultaneously. All recipients treated by triple-drug therapy (steroids, calcineurin inhibitors, mycophenolate mofetil), induction (thymoglobulin – n = 4, basiliximab – n = 1). We evaluated retrospectively laboratory-instrumental investigations and frequency of complications after HTx.Results.The median of survival after HT was 35,93 months (4,4–73,7 months), all of them are alive. Patients spent in ICU 12 days (4–18 days), but one – 18 days due to posterior reversible encephalopathy syndrome (PRES), tacrolimus was switched to cyclosporine. They required inotropic support during 3 days (3–8 days). In 1 yr after HT TTE results got to normal values, the same as VO2peak signifi cantly improved. According to EMB (n = 48) results there were no clinical signs of rejection, acute cellular rejection (R2) was diagnosed in 12,5% cases. In long-term follow-up there was no signifi cant post transplant complications and comorbidities.Conclusion.Pediatric heart transplantation is an effective treatment of terminal CHF. There was no signifi cant clinical rejection under combined immunosuppressive regimens. All patients recovered and went back to normal life. Physical capacity improved in all recipients.

P084 Post transplant DSA in a cohort of kidney recipients 8 to 16 years after transplantation

Aim We previously published a study (1998–2008) of 624 patients showing the association of pre-transplant DSA with poor kidney allograft survival. The aim of the current study was to assess development of post-transplant DSA in patients with well-functioning grafts >8 years after transplantation in comparison to patients with failed grafts. Methods HLA typing (A, B, C, DR, DQ) of recipients and donors was performed by standard serologic and/or DNA (SSP or SSO) methods. Anti-HLA antibody specificity was determined by single antigen beads (Lifecodes) on a Luminex platform. Though donors were not typed for DPB1 or DPA1 the de novo development of antibodies to DP alleles was presumed to be donor specific. Results Of 624 patients that were originally enrolled 131 were available for evaluation. 67 recipients had functioning kidney allografts 8 to 18 years after transplantation with >10 years follow up in 50% of these patients. The remaining 64 patients had graft failure (return to dialysis) with a median survival of 7.5 years. Of these patients, 44 (68%) had evidence of post-transplant DSA to HLA class 1 and/or class 2 as detected 0.1 to 5 years prior to graft failure. Most DSA positive recipients had antibodies to both Class 1 and 2 (32, 50%), whereas only 3 patients had DSA to Class 1 and only 9 patients had DSA to Class 2. Of patients with functioning grafts only 32% had evidence of DSA. In a new cohort transplanted in 2012–2015, that received identical induction and maintenance immunosuppression as the earlier cohort, similar DSA results were observed. Approximately, 33% of recipients with functioning kidney allografts had evidence of DSA whereas 65% of patients with failed grafts had DSA. In many cases, in both cohorts, the detection of a relatively low level of DSA occurred without concomitant clinical signs of rejection (e.g., a rise in creatinine). Conclusion As demonstrated in many studies of shorter duration the development of DSA was associated in this 18 year study with kidney allograft failure long after antibody has been detected and in the absence of standard clinical markers of rejection. Patients that exhibit persistent levels of DSA without clinical signs of rejection may benefit from enhanced immunosuppressive therapy to prevent damage to the kidney tubules and glomeruli that eventually lead to graft failure.

OR49: ASSESSMENT OF THE LUMINEX® SINGLE ANTIGEN AND C1q ASSAYS’ ABILITY TO CORRELATE DONOR SPECIFIC ANTIBODIES WITH KIDNEY TRANSPLANT REJECTION

Aim The association between donor specific antibodies (DSA) and renal transplant rejection has been generally established, but there are cases when a DSA is present without rejection. The Luminex® Single Antigen (SA) assay is the current standard for identifying Human Leukocyte Antigen (HLA) IgG antibody specificities and determining if they are donor specific. To improve the ability to discriminate between harmful and benign antibodies, the SA C1q assay was developed to detect antibodies that are capable of fixing complement. Our objective was to explore the detection capacity of the two assays and their correlation with kidney transplant rejection. Methods The study included 23 renal transplant recipients with transplant dysfunction. Patients in the study also had a biopsy with complement fixation, as exhibited by C4d deposition on >50% of the peritubular capillaries. Using sera from the time of the C4d + biopsy, the SA IgG assay and SA C1q assay were performed. Results Of the 23 study patients, all had DSA identified by the SA IgG assay: six with only Class I antibodies, three with only Class II antibodies, and 13 with both. Only 14 of the 23 patients had DSA detected by the C1q assay: six Class I only, seven Class II only, and one with both. The mean total of the DSAs was 12,353 by SA IgG and 18,843 by SA C1q. All but one of the patients with C1q + DSA had at least one IgG + DSA with MFI > 5000, whereas only two of the nine patients without a C1q + DSA had an IgG + DSA with MFI > 5000. Therefore, the C1q assay is relatively insensitive at lower MFI. Conclusion Complement fixation is dependent not only on the subclass of the antibody but also on the crosslinking of complement molecules. On a cell, multiple different antibodies together can additively reach the threshold for complement fixation. As shown in the data, the sensitivity of the C1q assay appears to be limited when renal damage is likely to have been caused by multiple weak antibodies in concert. Given that all of the patients studied had transplant dysfunction and signs of complement activation, these data suggest that the results of the SA C1q assay correlate poorly with clinical signs of rejection, whereas the standard SA IgG assay correlated in all 23 patients.

The Management of Antibody-Mediated Rejection in the First Presensitized Recipient of a Full-Face Allotransplant

We report on the management of the first full-face transplantation in a sensitized recipient with a positive preoperative crossmatch and subsequent antibody-mediated rejection (AMR). The recipient is a 45-year-old female who sustained extensive chemical burns, with residual poor function and high levels of circulating anti-HLA antibodies. With a clear immunosuppression plan and salvage options in place, a full-face allotransplant was performed using a crossmatch positive donor. Despite plasmapheresis alongside a standard induction regimen, clinical signs of rejection were noted on postoperative day 5 (POD5). Donor-specific antibody (DSA) titers rose with evidence of C4d deposits on biopsy. By POD19, biopsies showed Banff Grade III rejection. Combination therapy consisting of plasmapheresis, eculizumab, bortezomib and alemtuzumab decreased DSA levels, improved clinical exam, and by 6 months postop she had no histological signs of rejection. This case is the first to demonstrate evidence and management of AMR in face allotransplantation. Our findings lend support to the call for an update to the Banff classification of rejection in vascularized composite tissue allotransplantation (VCA) to include AMR, and for further studies to better classify the histology and mechanism of action of AMR in VCA.

A Four-Year Pathology Review of the Near Total Face Transplant

In December of 2008, our institution performed a near total face transplant. The patient was monitored for signs of rejection assessed by paired skin and mucosa biopsies. The results of histological review of 120 biopsies collected during the first 4 years posttransplant are discussed. All biopsies were stained with hematoxylin and eosin, periodic acid-Schiff, immunohistochemical and TUNEL assays and graded using the Banff 2007 classification. Grade III rejection was diagnosed clinically at weeks 45 and 66, posttransplant; week 45 was determined as folliculitis while the erythema episode at week 66 confirmed an acute rejection (AR) that required hospitalization. The mucosa frequently showed interface inflammation without clinical signs of rejection and was not present in skin biopsies. In all, 34 of the 45 mucosal biopsies (75%) showed these interface changes. Clinical symptoms concurred with skin pathology in two grade III rejections. The mucosa showed histologic signs of rejection more frequently, which may indicate: increased mucosal sensitivity to rejection, a different type or subtype of AR that is specific to the mucosa, or a nonspecific process such as a drug effect. With more data and world experience, the diagnosis of face transplant rejection will be better defined and the Banff classification enhanced.

Near-infrared lymphography as a minimally invasive modality for imaging lymphatic reconstitution in a rat orthotopic hind limb transplantation model

Wider application of vascularized composite allotransplantation (VCA) is limited by the need for chronic immunosuppression. Recent data suggest that the lymphatic system plays an important role in mediating rejection. This study used near-infrared (NIR) lymphography to describe lymphatic reconstitution in a rat VCA model. Syngeneic (Lewis-Lewis) and allogeneic (Brown Norway-Lewis) rat orthotopic hind limb transplants were performed without immunosuppression. Animals were imaged pre- and postoperatively using indocyanine green (ICG) lymphography. Images were collected using an NIR imaging system. Co-localization was achieved through use of an acrylic paint/hydrogen peroxide mixture. In all transplants, ICG first crossed graft suture lines on postoperative day (POD) 5. Clinical signs of rejection also appeared on POD 5 in allogeneic transplants, with most exhibiting Grade 3 rejection by POD 6. Injection of an acrylic paint/hydrogen peroxide mixture on POD 5 confirmed the existence of continuous lymphatic vessels crossing the suture line and draining into the inguinal lymph node. NIR lymphography is a minimally invasive imaging modality that can be used to study lymphatic vessels in a rat VCA model. In allogeneic transplants, lymphatic reconstitution correlated with clinical rejection. Lymphatic reconstitution may represent an early target for immunomodulation.

Effectiveness of Topical Immunosuppressants in Prevention and Treatment of Rejection in Face Allotransplantation

The use of topical immunosuppressants has been anecdotally reported for the treatment of rejection in vascularized composite allotransplantation. The aim of this study was to evaluate the effectiveness of topical tacrolimus and clobetasol in the prevention and treatment of rejection. Seventy-six hemiface allotransplants, between ACI (RT1) donors and Lewis (RT1) recipients, were performed in 11 groups and treated with topical tacrolimus or clobetasol, or in combination with systemic cyclosporine A and anti-αβ-T-cell receptor antibody for 1 week. Topical treatment increased the survival of the allograft in all groups. Best outcomes were obtained in the groups treated with systemic therapy and topical tacrolimus. Expression of proinflammatory cytokines interleukin 2, interferon γ, tumor necrosis factor α, and transforming growth factor β correlated with clinical signs of rejection and the final outcomes. Clobetasol application was associated with a marked depletion of lymphocytic populations, and dermal and epidermal atrophy. Both topical tacrolimus and clobetasol were effective in treating episodes of acute rejection, and the best outcomes were achieved when their application was initiated after systemic immunosuppression. Topical tacrolimus proved to be a preferable adjunct agent to the systemic therapy by preventing both the local and systemic complications.

Mirna Pattern Within the Bile as a Diagnostic Tool after Liver Transplantation

Aim: The international gold standard to detect acute rejection after liver transplantation (LTx) is liver biopsy, a procedure with considerable risks for the patient. In search for less invasive diagnostic tools, bile as a direct synthesis product of the transplanted liver may be analyzed in patients with external bile drain. microRNAs (miRNAs) are emerging as biomarkers for diagnosis and prediction of transplant rejection. The aim of our study was to analyze liver rejection-associated miRNAs in bile of LTx recipients and to evaluate their usability for detecting a transplant rejection. Material and methods: Patients (n=19) undergoing LTx with external bile drain were included in a prospective clinical study. Bile samples were collected at consecutive time points after LTx (postoperative days 1, 3, 5, 7) and when clinical signs of rejection were observed. We analyzed the level of the miRNAs 122, 194, 133a and 148a in bile samples and normalized the expression to total RNA. Bile samples of n=10 Patients with acute rejection and n=9 controls were used for PCR analysis. Results: Isolation of sufficient amounts of RNA from bile was possible and results were evaluable. miR-122, miR-194, and miR-148a were significantly up-regulated in the bile of patients with an episode of acute rejection, out of which miR-194 showed the strongest upregulation. MiR-133a was also upregulated, but the results were not significant. Conclusions: Bile analysis is a practicable tool to optimize diagnostics after liver transplantation, especially to distinguish between acute rejection and other tissue damage. Bile as a direct product can serve as diagnostic tool and might offer insight in regularly process during episodes of acute rejection.

Urinary proteomic shotgun approach for identification of potential acute rejection biomarkers in renal transplant recipients

BackgroundAcute rejection (AR) episodes in renal transplant recipients are suspected when plasma creatinine is elevated and other potential causes out ruled. Graft biopsies are however needed for definite diagnosis. Non-invasive AR-biomarkers is an unmet clinical need. The urinary proteome is an interesting source in the search for such a biomarker in this population.MethodsIn this proof of principle study, serial urine samples in the early post transplant phase from 6 patients with biopsy verified acute rejections and 6 age-matched controls without clinical signs of rejection were analyzed by shotgun proteomics.ResultsEleven proteins fulfilled predefined criteria for regulation in association with AR. They presented detectable regulation already several days before clinical suspicion of AR (increased plasma creatinine). The regulated proteins could be grouped by their biological function; proteins related to growth and proteins related to immune response. Growth-related proteins (IGFBP7, Vasorin, EGF and Galectin-3-binding protein) were significantly up-regulated in association with AR (P = 0.03) while proteins related to immune response (MASP2, C3, CD59, Ceruloplasmin, PiGR and CD74) tended to be up-regulated ( P = 0.13).ConclusionThe use of shotgun proteomics provides a robust and sensitive method for identification of potentially predictive urinary biomarkers of AR. Further validation of the current findings is needed to establish their potential clinical role with regards to clinical AR diagnosis.Trial registrationClinicalTrials.gov number NCT00139009

Osseointegração clínica-radiológica do compósito hidroxiapatita-lignina entre implante metálico e tecido ósseo em coelho

Para avaliar o compósito hidroxiapatita-lignina na osseointegração entre implante metálico e o tecido ósseo, foram utilizados 20 coelhos adultos, nos quais foi realizada uma falha óssea na face lateral proximal de ambas as tíbias. Na tíbia esquerda, introduziu-se, no canal medular, um pino intramedular de Schanz revestido com o compósito em sua parte rosqueada, após o preenchimento daquele com 1000mg do compósito. A falha cortical foi preenchida com o compósito. O mesmo foi feito na tíbia direita, porém sem a utilização do compósito, servindo como controle. A avaliação clínica baseou-se na deiscência, claudicação, sensibilidade dolorosa e circunferência tibial. Foram realizadas radiografias imediatamente após a cirurgia e aos oito, 30, 60, 90 e 120 dias do pós-operatório. A maioria dos animais apresentou evolução clínica normal. Nas radiografias do grupo tratado, houve decréscimo da radiopacidade no defeito e no espaço medular até tornar-se semelhante à do osso circunvizinho, quadro inverso ao do grupo-controle. Conclui-se que o compósito hidroxiapatita-lignina não mostrou indícios clínicos de rejeição e que o tecido visualizado na altura da falha óssea e ao redor do pino intramedular tinha radiopacidade semelhante à do osso circunvizinho, o que sugere que o material promoveu a integração com o tecido ósseo.

Repair of the lower and middle parts of the face by composite tissue allotransplantation in a patient with massive plexiform neurofibroma: a 1-year follow-up study

The risk to benefit ratio of face transplantation with a composite tissue allograft remains debatable, although this procedure is technically feasible. We report here a 1-year follow-up of a patient who underwent face transplantation with a composite tissue allograft. On Jan 21, 2007, a 29-year-old man with neurofibromatosis type 1 underwent resection of a massive plexiform neurofibroma diffusely infiltrating the middle and lower part of his face. The main goal was to restore both the cutaneous appearance and function of the face, including, in particular, control of orbicularis oculi and oris muscle contraction. The issues of immunosuppressive therapy, psychological outcome, and social reintergration were addressed, together with the monitoring of graft rejection by biopsies of the skin and mucosa. The initial postoperative course was uncomplicated. Two episodes of clinical rejection occurred on days 28 and 64. The second episode was associated with cytomegalovirus infection. Both episodes resolved favourably, with no further clinical signs of rejection, making the reduction of immunosuppressive treatment possible. A year after surgery, the functional outcome was very good, with successful sensory and motor reinnervation in the transplanted territory. Psychological recovery was excellent, with complete social reintegration. This case demonstrates the feasibility of surgically removing a large part of the face and replacing it with a composite tissue allograft. This facial repair procedure, which seems to have a satisfactory risk to benefit ratio, could be offered in rare and selected cases.

Detection of early renal transplant rejection by minimally-invasive monitoring of impedance variability

Background Allograft rejection that occurs after renal transplants is identified by surveillance biopsies or by abnormal laboratory and/or hemodynamic data. The latter are insensitive markers of rejection that may not appear until significant histologic damage has already occurred. Therefore, a sensitive and specific non-invasive method of detecting early rejection of transplanted solid organs is needed. Method A single canine renal allograft was implanted followed by bilateral nephrectomy. Bipolar pacing electrodes were implanted at each end of the transplanted kidney. A second set of electrodes was implanted in the liver, which served as a non-rejecting normal organ. Electrodes were connected to an implantable sensor placed in the subcutaneous tissue. Electrical tissue impedance levels were telemetrically downloaded daily. The clinical status of the transplanted organ was monitored by following the blood urea nitrogen and serum creatinine levels, urine output, and clinical appearance. After tissue impedance levels had stabilized, all immunosuppressants were abruptly discontinued. Clinical signs of rejection were then observed after a few days. Results Rejection was accompanied by changes in electrical impedance of the implanted organ. These changes, when observed, occurred 1–5 days before clinical signs of rejection appeared. Conclusion Analyses of these data suggest that development of a minimally-invasive high-confidence sensor of early rejection of solid organ transplants is feasible.

Thrombin Activatable Fibrinolysis Inhibitor in Hypertensive Kidney Transplant Recipients

Kidney transplant recipients are prone to hypertension, dyslipidemia, and cardiovascular death. Hypertension is associated with hemostatic abnormalities. Thrombin activatable fibrinolysis inhibitor (TAFI) is a glycoprotein that links coagulation and fibrinolysis. The purpose of this study was to assess TAFI concentrations in renal transplant recipients in relation to blood pressure. Additionally, we evaluated thrombin activity (thrombin-antithrombin complex [TAT], prothrombin fragments 1+2 [F1+2]), thrombomodulin (TM), and the degree of plasmin generation (plasmin-antiplasmin complex [PAP]) using commercially available kits. The studies were performed on 86 renal allograft recipients (48 women, 38 men) at age range 26 to 73 years. The immunosuppressive regimen consisted of cyclosporine (CsA), prednisone, and azathioprine (n = 58) or mycophenolate mofetil (MMF; n = 28). All patients maintained sufficient and stable graft function, showing no clinical signs of rejection. In patients with hypertension (n = 68), we observed significantly higher concentrations of TAFI and of markers of thrombin generation (F1+2, TAT), and of thrombomodulin with significantly prolonged euglobulin clot lysis time (ECLT), which reflects overall fibrinolytic activity and lower fibrinolytic activity index (FAI). Both groups did not differ with respect to age, creatinine clearance, body mass index, time after transplantation, albumin, fibrinogen, and PAP. Diastolic blood pressure correlated significantly with TAFI concentrations, uric acid, and prednisone dose, whereas systolic blood pressure correlated with urea, uric acid, creatinine clearance, and MCV. Elevated TAFI concentrations and enhanced thrombin generation in hypertensive kidney transplant recipients may contribute to the hypofibrinolysis and progressive atherosclerosis in this population. Blood pressure was related to kidney function, maintenance prednisone dose, and TAFI concentration.

Anti-TNF-Alpha Therapy for Acute Rejection in Intestinal Transplantation

Introduction We present our experience with infliximab rescue therapy for steroid- and OKT3-resistant rejection after intestinal transplantation (ITx). Methods Twelve ITx and one multivisceral transplant recipients were immunosuppressed with tacrolimus, rapamycin, daclizumab, steroids ( n = 10) or tacrolimus, campath, and steroids ( n = 3). Results In two patients, severe acute rejection did not resolve despite steroid bolus therapy plus 5 to 10 days of OKT3 treatment. Signs of moderate rejection persisted in the distal portions of the grafts. Treatment with infliximab, a chimeric anti-TNF-alpha antibody (four infusions of 3 mg/kg body weight), induced a complete remission of histological and clinical signs of rejection. Two further patients with steroid-resistant rejection received two courses of infliximab (3 mg/kg body weight) as antirejection therapy. All rejection episodes resolved completely. Conclusions Infliximab effectively treats steroid and OKT3 resistant acute rejection episodes of intestinal transplantations.

Effect of immunosuppression on survival of allograft limbal stem cells.

To examine whether the application of immunosuppression enhances the survival of limbal allograft stem cells. Wistar (allograft) or Fischer 344 (isograft) rat limbal tissue was transplanted into superior lamellar excision sites in Fischer 344 rats. Allograft-recipient rats received an immunosuppressive agent or vehicle for 8 weeks. Graft-recipient rats were examined by slit-lamp microscopy for clinical signs of rejection, and some recipients were killed for immunohistochemical analysis during rejection. One month from the time of transplantation, other (five in each group) recipients received daily injections of 5-bromo-2-deoxyuridine (BrdU) at a dose of 5 mg/100 g for 2 weeks, followed by a 1-month BrdU-free period before death. After the rats were killed, limbal allograft eyes were removed for BrdU staining to identify label-retaining cells. The labeling index of transplanted limbal basal epithelial cells was determined. In nonimmunosuppressed allograft recipients, clinical rejection occurred between days 5 and 10 after transplantation (median, 7 days). In contrast, rejection was suppressed for more than 60 days (median value) when the immunosuppressive was administered. Numerous MHC class II(+), CD4(+), and CD8(+) T cells were identified with acute rejection. Immunosuppressive-treated allografts had significantly less inflammation compared with untreated controls. Furthermore, immunosuppressive-treated allografts showed more label-retaining basal cells in transplanted limbal epithelium compared with untreated allograft controls ( P < 0.01). The survival of limbal allograft stem cells can be improved by immunosuppression. The limbal allograft procedure described here provides a useful model for evaluating a suitable alternative means of sustaining the survival of corneal stem cells.