Impact of Steroids on Natural Killer Cells Against Cytotoxicity and Hepatitis C Virus Replication.

BACKGROUND: Natural killer (NK) cells play important roles in killing tumor and virus-infected cells. Immunosuppression used after organ transplantation is thought to increase the risk of tumor recurrence and viral infections. However, the effect of immunosuppressive drugs on NK cells has not yet been clearly established. Therefore, we examined the effect of immunosuppression on NK cells. METHODS: NK cells were cultured for 7 days in the presence of interleukin-2 (100 U/mL) with or without the following immunosuppressive drugs: tacrolimus, cyclosporine A, corticosteroid (methylprednisolone [MP]), mycophenolate mofetil, and rapamycin. The effect of the drugs on NK cell activation was tested on the basis of the following: NK cell phenotype, NK cell proliferation, cytotoxicity against K562 cells, cytokine production by NK cells, and anti-hepatitis C virus (HCV) activity with HCV genomic replicon cells. RESULTS: NK cells showed relatively robust functions in the presence of tacrolimus and cyclosporine A. Mycophenolate mofetil and rapamycin significantly prevented only NK cell proliferation (P < .05). In contrast, MP significantly inhibited the proliferation, cytotoxicity, and anti-HCV effect (10.9%, 18.5%, and 1.9%, respectively) of NK cells. Furthermore, MP specifically inhibited the expression of NK cell activation markers and the production of interferon-γ (P < .05). CONCLUSIONS: Corticosteroids have distinct effects on NK cells, which may have important implications for NK cell function in cytotoxicity and HCV effect after transplantation.

Pilot Randomized Trial of Tacrolimus/Everolimus vs Tacrolimus/Enteric-Coated Mycophenolate Sodium in Adult, Primary Kidney Transplant Recipients at a Single Center.

BACKGROUND: Recent studies suggest that the combination of tacrolimus (TAC) and everolimus (EVL) could become a viable option for use as standard maintenance immunosuppression in non-highly sensitized kidney transplant recipients. METHODS: We conducted a single-center, open-label, randomized pilot trial comparing two maintenance immunosuppression regimens in non-highly sensitized, adult, primary kidney transplant recipients: (TAC/EVL, Group A) vs our standard maintenance regimen of TAC plus enteric-coated mycophenolate mofetil (TAC/EC-MPS, Group B). In both treatment arms, dual induction therapy consisting of anti-thymocyte globulin (Thymoglobulin) and basiliximab was given. Early corticosteroid withdrawal (by 7-10 days posttransplantation) was also planned in both arms. There were 30 study participants, 15 per treatment arm. Results during the first 12 months posttransplantation are reported here. RESULTS: Between 1 month and 12 months posttransplantation, mean TAC trough levels ranged between 5 and 8 ng/mL in both arms. Mean trough EVL level in Group A ranged between 4 and 6 ng/mL, and mean EC-MPS dose in Group B ranged from 1440 mg at 1 month to 945 mg at 12 months. One patient in Group A vs three patients in Group B experienced a first biopsy-proven acute rejection during the first 12 months posttransplantation (P = .32). Four patients in each group experienced biopsy-proven chronic allograft injury (interstitial fibrosis/tubular atrophy) (P = .99). There was a slight trend toward more favorable renal function in Group A at months 1-3 posttransplantation (P = .06, .10, and .18 for estimated glomerular filtration rate, respectively). No graft failures or deaths were observed in either group during the first 12 months posttransplantation. Four patients in each group developed an infection during the first 12 months posttransplantation. Two patients in Group A developed new-onset diabetes after transplant during the 12-month follow-up period, vs no patients in Group B (P = .13). CONCLUSION: TAC/EVL may be a viable alternative to TAC/EC-MPS for use as standard maintenance immunosuppression in non-highly sensitized kidney transplant recipients and should be given further consideration.

Eculizumab Salvage Therapy for Antibody-Mediated Rejection in a Desensitization-Resistant Intestinal Re-Transplant Patient.

The presence of elevated calculated panel reactive antibody (cPRA) and anti-HLA donor specific antibodies (DSA) are high risk factors for acute antibody-mediated rejection (AAMR) in intestinal transplantation that may lead to graft loss. Eculizumab has been used for the treatment of AAMR in kidney transplantation of sensitized patients that do not respond to other treatment. Here, we report a case where eculizumab was used to treat AAMR in a desensitization-resistant intestinal re-transplant patient. A male patient lost his intestinal graft to AAMR 8.14 years after his primary transplant. He received a second intestinal graft that had to be explanted a month later due to refractory AAMR. The patient remained highly sensitized despite multiple treatments. He received a multivisceral graft and presented with severe AAMR on day 3 posttransplantation. The AAMR was successfully treated with eculizumab. The patient presently maintains an elevated cPRA level above 90% but his DSAs have decreased from 18 000 MFI (mean fluorescent intensity) to below the positive cut-off value of 3000 MFI and remains rejection free with a 2-year follow-up since his multivisceral transplant. Eculizumab offers an alternative to treat AAMR in intestinal transplantation in desensitization-resistant patients.

Uterus transplantation model in sheep with heterotopic whole graft and aorta and cava anastomoses.

Uterine transplantation in the sheep model has been described as a partial or whole orthotopic graft from a living donor with vascular anastomoses. As an alternative to surrogate pregnancy or adoption uterus transplantation might be indicated for cases of infertility of uterine origin. The main complications might be rejection and thrombosis. The objective of this work was to develop a model of whole uterus transplantation that was applicable to the human setting, using grafts obtained from brain-dead donors, and suitable for immunologic and viability follow-up with a reduced risk of thrombosis. Two donors and 1 recipient were operated. The first graft was used for an anatomic study; the second was used for transplantation. The donor operation consisted of an en bloc harvest of the uterus, adnexa, and proximal vagina with the distal aorta and cava. After harvest the donor sheep was humanely killed. In the recipient ewe, heterotopic implantation was performed in the lower abdomen. An End-to-side anastomoses of aorta and cava were performed below the recipient's renal vessels. A cutaneous vaginal stoma was performed in the right lower quadrant. The recipient ewe was humanely killed for an autopsy study. The anatomy of uterine veins of the ewe differs from the human. The uterine and ovarian veins join, forming the utero-ovarian vein, which drains at the confluence of the common iliac to the cava. En bloc harvesting allows for rapid graft preparation, with vascular cuffs easily anastomosed with a low risk of thrombosis. The vaginal stoma seems appropriate to facilitate follow-up and graft biopsy. This approach can be a suitable experimental model applicable to humans using grafts from brain-dead donors.

Comparative analysis of T-cell depletion method for clinical immunotherapy-anti-hepatitis c effects of natural killer cells via interferon-γ production.

Liver transplantation (LT) is a life-saving treatment for liver cirrhosis patients with hepatocellular carcinoma (HCC). However, 10%-20% HCC recurrence rate after LT is due to the immunosuppression inducing tumor growth. We recently reported a novel immunotherapy with donor liver natural killer (NK) cells to prevent HCC and hepatitis C virus (HCV) recurrence after LT. In this cell processing procedure, Muromonab-CD3 (Orthoclone OKT3, an anti-CD3 antibody) was added to the culture medium to deplete CD3(+) T cells to prevent graft-versus-host disease. However, the manufacture of OKT3 was discontinued in 2010, when other treatments with similar efficacy and fewer side effects became available. In this study, we examined alternative reagents for T-cell depletion-MACS GMP CD3 pure (GMP CD3), antithymocyte globulin, and alemtuzumab-for NK cell immunotherapy in the allogeneic setting. We observed that GMP CD3 showed exactly the same effects on liver mononuclear cells as OKT3, including activation of NK cells and depletion of T cells. Interestingly, binding of T-cell depletion antibodies to NK cells led to an anti-HCV effect via interferon-γ production. These results with the use of in vitro culture systems suggested that antibodies which produce T-cell depletion affected NK cell function.

Preclinical report on allogeneic uterus transplantation in non-human primates.

STUDY QUESTION: Is it possible to perform allogeneic uterus transplantation (UTx) with a donation from a live donor in a non-human primate species and what immunosuppression is needed to prevent rejection? SUMMARY ANSWER: Allogeneic UTx in the baboon is a donor- and recipient-safe surgical procedure; immunosuppression with induction therapy and a triple protocol should be used. WHAT IS KNOWN ALREADY: UTx may become a treatment for absolute uterine factor infertility. Autologous UTx models have been developed in non-human primates with reports on long-term survival of the uterine grafts. STUDY DESIGN, SIZEAND DURATION: This experimental study included 18 female baboons as uterus donors and 18 female baboons as uterus recipients. The follow-up time was 5-8 weeks. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Uterus retrieval was performed with extended hysterectomy including bilateral uterine and internal iliac arteries and ovarian veins. After UTx, with vascular anastomoses unilateral to the internal iliac artery and the external iliac vein, the uterus recipients received one of the following: no immunosuppression (n = 4); monotherapy (oral slow release tacrolimus) (n = 4) or induction therapy (antithymocyte globulin) followed by triple therapy (tacrolimus, mycophenolate, corticosteroids; n = 10). Surgical parameters, survival, immunosuppression and rejection patterns were evaluated. MAIN RESULTS AND THE ROLE OF CHANCE: The durations of uterus retrieval and recipient surgery were around 3 and 3.5 h, respectively. The total ischemic time was around 3 h. All the recipients and the donors survived the surgery. All the recipients presented rejection to some extent within the first weeks following UTx. In one recipient, the uterus was of normal appearance at the end of the study period. In spite of occasional high (>60 ng/ml) blood levels of tacrolimus, there was no evidence of nephrotoxicity. LIMITATIONS AND REASONS FOR CAUTION: This initial non-human primate allogeneic UTx study indicates that further research is needed to optimize immunosuppression protocols in order to avoid uterine rejection. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest that allogeneic UTx in primate species is feasible but continued work on this issue is needed. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the Swedish Research Council, ALF University of Gothenburg, Hjalmar Svensson Foundation and by Jane and Dan Olsson Research Foundation. The authors do not have any competing interest.

Citrulline level is a potent indicator of acute rejection in the long term following pediatric intestinal/multivisceral transplantation.

Citrulline has been advocated as a marker for acute cellular rejection (ACR) in intestinal transplantation; however, its significance as a forewarning in the long-term follow-up remains unknown. This study aimed to investigate the association between citrulline levels and the grading of ACR to establish a cutoff point that accurately predicts ACR beyond 3 months posttransplant in the pediatric patient population. During a 16-year period (1995-2011), a total of 13 499 citrulline samples were prospectively collected from 111 consecutive pediatric intestinal/multivisceral transplant recipients: 2155 were obtained concurrently with intestinal biopsies. There were 185 ACR episodes observed among 74/111 (67%) patients (median follow-up: 4.4 years). Citrulline levels were inversely proportional to the severity of ACR. Negative predictive values for any type of ACR (cutoff, 20 µmol/L) and moderate/severe ACR (cutoff, 10 µmol/L) were 95% and 99%, respectively. When patients were divided according to graft size, diagnostic accuracy using the same cutoff was identical. Similarly, subgroup analysis by the timing of citrulline measurement prior to biopsy varying from 1 to 7 days demonstrated comparable results. Citrulline is a potent indicator as a danger signal for ACR, being an exclusionary, noninvasive biomarker with excellent negative predictive values in the long term after pediatric intestinal/multivisceral transplant.

MicroRNA signature of intestinal acute cellular rejection in formalin-fixed paraffin-embedded mucosal biopsies.

Despite continuous improvement of immunosuppression, small bowel transplantation (SBT) is plagued by a high incidence of acute cellular rejection (ACR) that is frequently intractable. Therefore, there is a need to uncover novel insights that will lead to strategies to achieve better control of ACR. We hypothesized that particular miRNAs provide critical regulation of the intragraft immune response. The aim of our study was to identify miRNAs involved in intestinal ACR. We examined 26 small intestinal mucosal biopsies (AR/NR group; 15/11) obtained from recipients after SBT or multivisceral transplantation. We investigated the expression of 384 mature human miRNAs and 280 mRNAs associated with immune, inflammation and apoptosis processes. We identified differentially expressed 28 miRNAs and 58 mRNAs that characterized intestinal ACR. We found a strong positive correlation between the intragraft expression levels of three miRNAs (miR-142-3p, miR-886-3p and miR-132) and 17 mRNAs including CTLA4 and GZMB. We visualized these miRNAs within cells expressing CD3 and CD14 proteins in explanted intestinal allografts with severe ACR. Our data suggested that miRNAs have a critical role in the activation of infiltrating cells during intestinal ACR. These differences in miRNA expression patterns can be used to identify novel biomarkers and therapeutic targets for immunosuppressive agents.

Split liver transplantation.

We analyzed the results of 55 patients who underwent split liver transplantation at our center between September 1996 and December 2008, 30 adults (54.5%) and 25 children (45.5%). Median follow-up was 12 years. Overall patient survival was 71%, adult 70% and pediatric 72%. Mean patient survival was 61.58 months, and mean graft survival was 44.35 months. Pediatric survival and pediatric graft survival after 1 and 5 years were 84% and 72% and 72% and 52.4%, respectively. Adult survival and adult graft survival after 1 and 5 years were 75% and 66.2% and 60.7% and 51.5%, respectively. Twelve patients required retransplantation, 6 for primary nonfunction, 3 for chronic rejection, and 3 for vascular complications. Blood groups of the recipient patients were: 34 O, 14 A, 7 B, and 0 AB. The use of split liver for adult and pediatric populations allows us to expand the cadaveric donor pool and has the potential to significantly reduce waiting list mortality, especially for certain blood groups.

Identifying the support needs of fathers affected by post-partum depression: a pilot study.

The purpose of this pilot study was to describe the experiences, support needs, resources, and barriers to support for fathers whose partners had post-partum depression (PPD) in preparation for a larger study. Qualitative methods and community-based research approaches were used in this exploratory/descriptive multi-site study, conducted in New Brunswick and Alberta. Telephone interviews were conducted with a total of 11 fathers in New Brunswick (n= 7) and Alberta (n= 4). Fathers experienced a number of depressive symptoms including: anxiety, lack of time and energy, irritability, feeling sad or down, changes in appetite, and thoughts of harm to self or baby. The most common barriers for fathers were lack of information regarding PPD resources and difficulty seeking support. This pilot study establishes the feasibility of the larger-scale exploration of fathers' experiences in supporting their spouses affected by PPD.

Association between panel reactive antibodies and acute small bowel rejection: analysis of a series of 324 intestinal transplants.

INTRODUCTION: Panel reactive antibodies (PRA) to class I and II HLA molecules have been associated with acute kidney graft rejection, but their role in small bowel transplantation has not been characterized. METHODS: Since 1994, 324 SBT, alone or as multivisceral transplantation (MVT), have been performed in 286 patients. Routine and surveillance biopsies were performed to rule out or confirm acute rejection (AR), and PRA quantification was performed at varying intervals. We obtained data from 110 patients and 651 PRA measurements. While AR grade (mild to severe, grades 1-3) was determined by histopathological analysis, the status of no AR was determined also by clinical data. When biopsy samples or PRA measurements were frequent around an AR episode within periods of 7 days, the highest value was used. RESULTS: A comparison could be made between 259 instances in which there was a PRA measurement and simultaneous rejection evaluation. Positive PRA showed association with AR (P < 0.001). The positive and negative predictive values were 44% and 79%, respectively. No correlation was found in the severity of rejection. CONCLUSION: The presence of increased levels of PRA is a risk factor of rejection in small bowel transplantation. Alloantibody-mediated injury to the graft contributes frequently to acute rejection of small bowel, and it is associated with cell-mediated immunity in variable proportion.

Citrulline evaluation in bowel transplantation.

INTRODUCTION: The purpose of this study was to evaluate the correlation of plasma citrulline and rejection episodes in intestinal transplantation. METHODS: From January 2007 until present, we performed citrulline assays on our small bowel patients. We investigated the correlation of these assays with the rejection status of the patients. The rejection status of the graft was defined based on graft biopsies. RESULTS: Of 5195 citrulline samples, average serum citrulline levels decreased significantly when the patients presented a rejection episode. We found the following: no rejection, 17.38 microm/L; mild rejection, 13.05 microm/L; moderate rejection, 7.98 microm/L; and severe rejection, 6.05 microm/L. Our current emphasis is to determine the predictive power of citrulline with other biomarkers versus as a separate and isolated measurement. CONCLUSIONS: In our study, citrulline levels correlated significantly with the rejection status of the graft. Serial follow-up of the patients using this assay may alert us to the possibility of increased alloreactivity and rejection episodes.

Gene expression profiling of MicroRNAs in small-bowel transplantation paraffin-embedded mucosal biopsy tissue.

BACKGROUND: The molecular mechanisms and regulation of immune-mediated rejection of organ allografts remains unclear. Recent studies have reported that small non-coding RNAs, microRNAs (miRNAs) play a critical role in the immune system via modulation of transcription and translation. PURPOSE: We hypothesized that particular miRNAs provide regulation of an ensuing intragraft immune effector response. The aim of our study was to detect miRNAs involved in acute cellular rejection (AR) in human small intestinal allografts. MATERIALS: We examined 12 small intestinal mucosal biopsies (AR, 7 cases, all grade 2 or 3) and non-rejecting (NR) allografts (5 cases, all grade 0) obtained from recipients after small bowel or multivisceral transplantation. RNA was isolated from the formalin-fixed paraffin-embedded (FFPE) biopsy samples and transcribed to cDNA. After preamplification we utilized a PCR based TaqMan Low Density Array (TLDA) containing 365 mature human miRNAs. Relative quantification was done based on pooled normal intestine using a comparative Ct method. RESULTS: We identified 62 miRNA upregulated genes in small bowels with ACR, and 35 were downregulated. Forty-two miRNA genes were upregulated in non-ACR small bowel biopsy samples (grade IND), and 45 were downregulated. The relative fold change ratio of ACR to non-ACR was calculated, and 50 upregulated and 8 downregulated miRNAs were detected as significant. Several interesting miRNAs will be evaluated further from this preliminary study. Our data suggests that intragraft miRNAs are potentially involved in the activation of a host alloimmune response to donor. These miRNAs may serve as targets for appropriate intervention and may be useful to monitor the allograft status.

Mycophenolate mofetil-related gastrointestinal mucosal injury in multivisceral transplantation.

Mycophenolate mofetil (MMF) has become an important and commonly used drug for maintenance immunosuppression therapy in recipients of all types of organ transplants. The drug is an antimetabolite that blocks the de novo pathway of purine synthesis. Although it selectively inhibits B- and T-lymphocyte proliferation, enterocytes are partially susceptible to MMF. One of the main limitations of this drug is gastrointestinal toxicity, with diarrhea the most frequently reported adverse effect. Most studies of MMF-associated gastrointestinal toxicity have been performed in patients with solid-organ transplants, although no data on changes related to MMF toxicity in bowel allografts have been published in the English literature. We evaluated mucosal intestinal biopsy tissue from patients with multivisceral transplants receiving MMF therapy. Our objective was to find morphologic changes that might be attributed to MMF toxicity, as well as changes that could differentiate MMF toxicity from acute rejection. Examination of the surface epithelium, lamina propria, and crypts in this small group of patients showed no specific changes that could be associated with MMF toxicity. Changes such as graft-vs-host disease or inflammatory bowel disease described in previous studies of solid-organ transplantation were not observed. Larger studies and the use of special stains and new markers might be necessary to characterize possible patterns of MMF toxicity and their differences from acute rejection.

Immediate antibody-mediated (hyperacute) rejection in small-bowel transplantation and relationship to cross-match status and donor-specific C4d-binding antibodies: case report.

BACKGROUND: The role of preformed donor-specific antibodies (DSAs) as a barrier to isolated intestinal transplantation (ITx) remains ambiguous; thus, a positive cross-match has not been a contraindication to ITx. OBJECTIVE: To report the case of a patient with Crohn's disease who underwent ITx and developed immediate antibody-mediated rejection on reperfusion of the allograft. METHODS: Percent reactive antibody testing was performed using pretransplantation serum samples and at transplantation using bead-based assays (Luminex, Luminex Corp, Austin, Tex) and flow cytometry solid-phase assays (FlowPRA single-antigen beads (One Lambda, Inc, Canoga Park, Calif). Serologic tests, flow cytometry cross-matching, and flow cytometry assays of C4d-binding serum antibodies were also performed. Histologic and immunofluorescent analysis of biopsy specimens was performed. RESULTS: HLA typing revealed no sharing of class I or II antigens between donor and recipient. Pretransplantation donor-specific antibodies (DSA) were present at transplantation. Cross-matching (performed during surgery) was positive for class I and II by serologic testing and flow cytometry. After reperfusion, the graft immediately developed severe ischemic injury and arteritis on mucosal biopsy specimens, with immunoglobulin deposition. The DSA C4d binding antibodies were also present. After intense immunosuppression and plasmapheresis, the graft and the biopsy histologic findings showed marked improvement (day 2). By day 7 posttransplantation, patient and graft status were stable. The patient has remained clinically stable for more than a year after transplantation. CONCLUSIONS: Pretransplant DSA in ITx can be a risk factor for immediate (hyperacute) but potentially reversible antibody-mediated rejection. Thus, pretransplantation DSA and cross-match results are critical components to be considered in patients awaiting or undergoing ITx.

The Miami experience with almost 100 multivisceral transplants.

We report our experience with 98 patients who received primary multivisceral transplantations. Three eras can be distinguished based on the evolution of technique, immunosuppression, and monitoring: August 1994 to December 1997 (first era); January 1998 to December 2000 (second era); and January 2001 to present (third era). Sixteen patients were transplanted during the first era, 18 during the second era, and 64 during the third era. Fifty-three patients are alive with a median follow-up of 37.5 months (range: 1 to 116 months). The leading cause of mortality was infection (n = 17), followed by rejection (n = 6). Seven patients required retransplantation and five of them subsequently died. The estimated 3-year survival was 25% +/- 11% for era 1; 44% +/- 12% for era 2; and 58% +/- 7% for era 3. Additionally, 45.3% (29/64) of patients in the third era never developed rejection versus 23.5% (8/34) of patients in the first two eras combined. The percentage of patients who developed a moderate or severe rejection was significantly less in the third era compared with the first two eras combined, 31.6% (20/64) versus 67.6% (23/34). A comparison of the hazard rate of developing severe rejection showed a protective effect of the multivisceral graft (P = .0001). In conclusion, multivisceral transplantation is indicated for patients with short bowel syndrome and extended abdominal catastrophies. Evolution in surgical techniques, immunosuppression, and monitoring have improved patient survival, which is now similar to that of other complex solid organ transplants.

International grading scheme for acute rejection in small bowel transplantation: implementation and experience at the University of Miami.

In 2003, an international collection of pathologists and clinicians proposed a unified grading system for acute cellular rejection in endoscopically derived small intestine allograft biopsies. This grading system was implemented at the University of Miami over the past 2 years and the results are presented herein. A total of 1136 small bowel allograft biopsies with sufficient tissue for analysis were obtained from 123 hospitalized, clinic, and referral patients. The overall most common diagnosis assessing all time periods was grade IND (40%), and grade 1 rejection or greater was present in 19% percent of biopsies. A suspected vascular component to the acute rejection as identified by specific mucosal vascular changes was present in 6% of cases. Clinical decision making was very consistent with different grades. Our experience has confirmed that this new grading system is reliable and identifies clinical subsets of patients that can receive different therapy. We recommend that this international grading system be implemented for acute cellular rejection in bowel allografts as a means to standardize pathological assessment of alloimmune-induced graft injury, which will allow comparisons between different centers and clinical trials.

Mucosal fibrosis in intestinal transplant biopsies correlates positively with the development of chronic rejection.

Endoscopic biopsies of intestinal allografts are limited to the superficial layers of the bowel. We investigated whether the presence of mucosal fibrosis in graft biopsies was indicative of chronic allograft rejection. We examined graft biopsies of 182 intestinal transplant recipients for the presence of mucosal fibrosis. Kaplan-Meier analysis showed that within 5 years posttransplantation 33% of intestinal transplant patients had graft biopsies positive for mucosal fibrosis. Although the presence of mucosal fibrosis did not affect patient or graft survival, patients with this lesion were at higher risk of developing chronic allograft enteropathy.

An association of lower serum citrulline levels within 30 days of acute rejection in patients following small intestine transplantation.

INTRODUCTION: In a prospective protocol we studied whether serum citrulline level within 30 days of an acute rejection was predictive of the episode. METHODS: An acute rejection episode was defined as the date of occurrence of any biopsy-proven rejection in which treatment was initiated until two successive biopsies showed no further rejection. We compared the mean citrulline level based on values determined within 30 days of the start of an acute rejection episode with the mean citrulline level measured on the same patient during a rejection-free period. Serum citrulline measurements were available immediately prior to the occurrence of rejection for 22 patients who experienced 37 episodes. RESULTS: For the 12 episodes of mild rejection, the mean serum citrulline level +/- SE (standard error) was 15.0 + 2.3 micromol/L prior to rejection and 18.8 +/- 2.4 micromol/L during the rejection-free periods. A paired t test of the mean differences was not significant (P = 17). For the 25 episodes of moderate or severe rejection, the mean serum citrulline level was 12.4 +/- 1.1 micromol/L before rejection and 18.8 +/- 2.0 micromol/L during the rejection-free periods. A paired t test of the mean difference was statistically significant (P = .002). CONCLUSIONS: Although further study of citrulline as a marker for the early detection of acute rejection episodes is needed, our hope is that its use will help to prevent some of these early episodes from evolving into full-blown moderate or severe grades of rejection.

Intestinal transplantation with alemtuzumab (Campath-1H) induction for adult patients.

BACKGROUND: Alemtuzumab (Campath-1H [C1H]) is a humanized monoclonal antibody directed against the CD 52 antigen that is present on the surface of T cells, B cells, natural killer cells and monocytes. We studied its application in intestinal transplantation. METHODS: This is a retrospective review of adult patients who underwent intestinal transplantation between December 1994 and May 2005. Group 1: non-C1H group (n = 39); group 2: C1H group (n = 37). C1H was administered as an induction immunosuppression in four doses (0.3 mg/kg), or in two doses (30 mg/kg). Tacrolimus levels were maintained at low level (5-10 ng/dL). No maintenance steroids were given. RESULTS: One-year survival of group 1 and group 2 patients were 57% and 70%, respectively. This difference is not statistically significant. Of 37 patients in group 2, 21 are alive. The incidence of rejection was lower in group 2 (P < .005). Average current tacrolimus level is 6.97 +/- 3.98 ng/dL. Seventeen patients (81%) are steroid free, and 15 (71%) are maintained solely on tacrolimus. There was no graft versus host disease in group 2. CONCLUSIONS: Our preliminary data suggest that C1H can provide effective immunosuppression for intestinal transplantation. Incidence of rejection was less with this regimen using low maintenance tacrolimus and minimal steroids.