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Background. Laparoscopic donor nephrectomy (LDN) of the right kidney is performed with great reluctance because of the shorter renal vein and possible increased incidence of venous thrombosis. Methods. In this retrospective, clinical study, right LDN and left LDN were compared. Between December 1997 and May 2001, 101 LDN were performed. Seventy-three (72%) right LDN were compared with 28 (28%) left LDN for clinical characteristics, operative data, and graft function. Results. There were no significant differences between the two groups regarding conversion rate, complications, hospital stay, thrombosis, graft function, and graft survival. Operating time was significantly shorter in the right LDN group (218 vs. 280 min). Conclusion. In this study, right LDN was not associated with a higher number of complications, conversions, or incidence of venous thrombosis compared with the left LDN. Thus, reluctance toward right LDN is not justified, and therefore, right LDN should not be avoided.

Despite attempts to establish a situation of tolerance to an allograft, at present, kidney transplantation is inevitably associated with the use of immunosuppressive drugs and, consequently, an increased risk of infection [1,2]. Here we present a patient with a kidney transplant who developed a bacteraemia with Yersinia pseudotuberculosis 5 years after transplantation, which is a rare complication of Y.pseudotuberculosis infection and has been reported only once before in the context of kidney transplantation.

Imagine a Samaritan living kidney donor, who some time ago has anonymously donated one of his kidneys to a patient on top of the waiting list. He now contacts the transplantation centre once again, to donate part of his liver. The Centre, startled by this idea, refers him to the regular screening procedure for all Samaritan donations. It turns out that his wish is well-informed, voluntarily made and that he is competent to decide. We acknowledge that a donor's wish should not be followed in all cases, even though this wish is a clear expression of his own free will. However, a refusal must be based on sound moral reasons and it is less clear what reasons these might be. We outline the most common arguments for refusal, assess these arguments in terms of strengths and weaknesses, and show which arguments, if any at all, are most promising. We conclude, firstly, that we should only assess risks (which include motivations), not judge relationships, and secondly, that it is not a transplant centre's mission to carry out a donor's life project.

Objective We investigated the association between genetic polymorphisms in ABCB1 and SLCO1B and mycophenolic acid (MPA) pharmacokinetics, and MPA-related diarrhea and leukopenia in 338 kidney transplant recipients. Methods A total of 338 patients participating in an international, randomized-controlled clinical trial were genotyped for ABCB1 and SLCO1B. Patients were all treated with mycophenolate mofetil and either cyclosporine or tacrolimus. MPA-area under the curve (AUCs), MPA-glucuronide AUCs and acylglucuronide-AUCs were measured on days 3 and 10, and months 1, 3, 6, and 12 after kidney transplantation. Results The risk of developing diarrhea was 1.8-fold higher in patients cotreated with tacrolimus compared with patients cotreated with cyclosporine (95% confidence interval: 1.03-3.13; P = 0.038). ABCB1 and SLCO1B SNPs were not associated with dose-adjusted exposure to MPA, MPA-glucuronide, nor acylglucuronide-MPA nor with the incidence of diarrhea or leukopenia. Conclusion Genotyping for ABCB1 or SLCO1B pretransplantation is unlikely to be of clinical value for individualization of MPA therapy. Pharmacogenetics and Genomics 22: 399-407 (C) 2012 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Living donor kidney exchange has become an efficient solution for recipients with incompatible donors. Here we describe the fate of all patients that were enrolled in our program during 2004-2010.Data on registration, computerized matching, cross matching, and transplantations within or outside the program were collected.Between January 2004 and December 2010, 422 pairs were registered. To create new combinations a match procedure was run 28 times with a median input of 14 (7-22) new pairs and a median of 55 (16-92) participating pairs. Matches were found for 127/185 (69%) cross match-incompatible pairs and 91/237 (38%) ABO-incompatible pairs. 141 of the 218 matched pairs successfully donated and received kidneys in exchange. There were 77 transplants cancelled for medical or psychological reasons, and an alternative solution was found for 26 of these. So in total 167 (141 + 26) patients received a transplant. Of the remaining 51 cancelled transplants, 26 pairs dropped out, 22 patients found an alternative transplantation outside the program and 3 are still waiting. For the 204 unmatched couples, 46 are still in the program while 34 others dropped out, and 124 found an alternative living kidney donor. After 7 years, 39% of participants received a kidney within the exchange program, 35% were transplanted outside the program, 14% of the pairs were delisted and 12% are still waiting. Among the 146 patients who received a kidney outside the program, 47 were transplanted with a deceased donor kidney, 21 found another donor, 37 received an ABO-incompatible transplant and 41 were transplanted in a domino-paired procedure triggered by an non-directed donor.In the 7 years of our Living Donor Kidney Exchange Program 313/422 (74%) of the participating patients were transplanted. Approximately half of them (167/313, 53%) received a kidney through the exchange program, while 47 (15%) received a deceased donor kidney and 99 (32%) were transplanted through other living donation programs. The exchange program proved to be highly successful not only in its direct results but also indirectly by triggering alternative solutions.

Background: The risk of long-term chronic allograft nephropathy and graft loss after kidney transplantation is increased in patients with a high intrapatient variability of tacrolimus (Tac) clearance. Methods: To test whether this intrapatient variability is associated with an individual's CYP3A5 genotype, we measured the intrapatient variability in Tac clearance in a cohort of 208 kidney transplant recipients treated with Tac and mycophenolate mofetil. Results: Tac dose requirement was significantly higher in patients expressing CYP3A5. However, intraindividual variability of Tac clearance was not related to CYP3A5 genotype. Conclusions: Intraindividual variability in Tac clearance is not related to CYP3A5 genotype. Other factors, including patient adherence, may explain the variability in Tac clearance within an individual patient over time.

Background. Allo-human leukocyte antigen (HLA) reactivity by naturally acquired viral-specific memory T cells is common. However, the effect of successful vaccination on the alloreactive memory T-cell repertoire is unclear. We hypothesized that vaccination could specifically induce allo-HLA-reactive memory T cells. Methods. A varicella-zoster virus (VZV) immediate early 62 (IE62)-specific CD8 memory T-cell clone was single cell sorted from a VZV seronegative renal transplant candidate after response to live attenuated varicella vaccination. To analyze the allo-HLA reactivity, the VZV IE62-specific T-cell clone was tested against HLA-typed target cells and target cells transfected with HLA molecules, in both cytokine production and cytotoxicity assays. Results. The varicella vaccine-induced VZV IE62-specific T-cell clone specifically produced interferon-gamma when stimulated with HLA-B*55:01-expressing Epstein-Barr virus-transformed B cells and HLA-B*55:01-transfected K562 cells (single HLA antigen expressing cell line [SALs]) only. The clone also demonstrated specific cytolytic effector function against HLA-B*55:01 SALs and phytohemagglutinin blasts. Cytotoxicity assays using proximal tubular epithelial cell and human umbilical vein endothelial cell targets confirmed the kidney tissue specificity of the allo-HLA-B*55:01 reactivity, and the relevance of the cross-reactivity to clinical kidney transplantation. The results also suggest that molecular mimicry, and not bystander proliferation, is the mechanism underlying vaccine-induced alloreactivity. Conclusions. Varicella vaccination generated a de novo alloreactive kidney cell-specific cytolytic effector memory T cell in a patient awaiting renal transplantation. Vaccination-induced alloreactivity may have important clinical implications, especially for vaccine timing and recipient monitoring.

In the literature, varying terminology for living organ donation can be found. However, there seems to be a need for a new classification to avoid confusion. Therefore, we assessed existing terminology in the light of current living organ donation practices and suggest a more straightforward classification. We propose to concentrate on the degree of specificity with which donors identify intended recipients and to subsequently verify whether the donation to these recipients occurs directly or indirectly. According to this approach, one could distinguish between "specified" and "unspecified" donation. Within specified donation, a distinction can be made between "direct" and "indirect" donation.

Item does not contain fulltext BACKGROUND: Cardiovascular disease is both a major threat to the life expectancy of kidney transplant recipients and an important determinant of late allograft loss. Obesity is an important risk factor for cardiovascular disease. METHODS: We investigated the relation between both pretransplant and 1-year posttransplant body mass index (BMI) with patient and renal graft survival in a cohort of 1810 adult patients. Sixty-one percent of all patients were men; median age (interquartile range [IQR]) was 46 years (35-56 years); median (IQR) pretransplant BMI was 23.0 kg/m (20.8-25.6 kg/m); 1 year after transplantation, the median (IQR) BMI had increased 1.6 kg/m (0.3-3.2 kg/m) and median (IQR) follow-up time was 8.3 years (5.3-12.0 years). We categorized BMI as follows: less than or equal to 20, more than 20 to less than or equal to 25 (normal), more than 25 to less than or equal to 30, and more than 30 (obesity) kg/m. RESULTS: Using a Cox proportional hazards model, after adjustment for cardiovascular risk factors, the relative risks (95% confidence intervals) of death and death-censored graft failure during all follow-up for pretransplant obesity compared with normal BMI were 1.22 (0.86-1.74) and 1.34 (1.02-1.77), respectively; for obesity 1 year after transplantation compared with normal BMI, it was 1.39 (1.05-1.86) and 1.39 (1.10-1.74), respectively; and for change in BMI (per 5 kg/m increment) during the first year after transplantation, it was 1.23 (1.01-1.50) and 1.18 (1.01-1.38), respectively. CONCLUSIONS: One year posttransplant BMI and BMI increment are more strongly related to death and graft failure than pretransplant BMI among kidney transplant recipients. Patients with BMI more than 30 kg/m compared with a normal BMI have approximately 20% to 40% higher risk for death and graft failure.

In this article, an ethical analysis of an educational programme on renal replacement therapy options for patients and their social network is presented. The two main spearheads of this approach are: (1) offering an educational programme on all renal replacement therapy options ahead of treatment requirement and (2) a home-based approach involving the family and friends of the patient. Arguments are offered for the ethical justification of this approach by considering the viewpoint of the various stakeholders involved. Finally, reflecting on these ethical considerations, essential conditions for carrying out such a programme are outlined. The goal is to develop an ethically justified and responsible educational programme.

We analyzed the results of passive immunization against CMV in 146 heart transplant recipients. The 65 seronegative recipients were prophylactically treated with anti-CMV immunoglobulins during and after the operation. Twenty-nine of these 65 patients received a seropositive donor heart. CMV infection occurred in 21/65 seronegative and in 40/81 seropositive recipients (difference not significant). The incidence of CMV infection in seronegative recipients of a CMV-matched donor heart (3/34) was significantly lower than in seronegative recipients of a positive donor heart and lower than in seropositive recipients, but no significant difference in infection rate was found between the two latter groups (18/29 vs. 40/81). Although primary infection more frequently resulted in CMV disease than secondary infection (11/21 vs. 10/40) no difference in incidence of disease was noted between seronegative and seropositive patients (11/65 vs. 10/81), nor was there a difference in the severity of symptoms following primary or secondary infection. There was a higher incidence of CMV disease in all patients who received a heart from a seropositive donor versus a seronegative donor. However, after transplantation of a heart from a seropositive donor the incidence (27%) of CMV disease observed in our passively immunized seronegative patients was the same as in the patients with naturally acquired seropositivity. There was no difference in the prevalence of coronary artery disease between patients with and without CMV infection or disease. We conclude that using the current passive immunization scheme the occurrence of CMV infection and disease is largely dependent on the serostatus of the donor.

Several studies published in 2014 might facilitate improvements in the treatment and long-term care of renal transplant recipients. The potential risks of living kidney donation, the efficacy and safety of alemtuzumab-based induction therapy, and the treatment of chronic hepatitis E virus infection have been addressed.

The in vitro cytotoxic reactivity of allograft infiltrating cells cultured from endomyocardial biopsies was tested against endothelial cells (EC) isolated from the own donor heart. EC derived from pieces of atrium were found to be proper targets for graft infiltrating cytotoxic T cells from four patients. The specificity of this cytotoxicity was further analysed by cold target inhibition studies and blocking with anti-CD3, anti-CD4 or anti-CD8 monoclonal antibodies. The experiments revealed that, besides a clearly HLA directed recognition, a more heterogeneous, multispecific response can be found, which might be partially explained by the activity of EC specific T cell clones. We conclude that this system provides a valuable approach to investigate the reactivity of graft infiltrating cells against EC in relation to the clinical course of the transplantation.

The risk of urologic complications after kidney transplantation is 0% to 30%. We studied the impact of prophylactic stent placement during transplantation by assessing the necessity for a percutaneous nephrostomy (PCN) after living kidney transplantation. From January 2003 to December 2007, 342 living donor kidney transplantations were performed. Intra- and postoperative data were collected retrospectively from 285 patients with stent and 57 without. Baseline characteristics were not significantly different between groups, except for the number of previous transplantations: 31 (11%) patients with versus 16 (28%) without stent had a history of >1 transplantation (P < .001). From patients with PCN, 55 (87%) patients in the stented group received a PCN

Background. Non- adherence to the post-transplant regime is a common problem in kidney transplant patients and may lead to rejection or even graft failure. This study investigated attitudes towards the post-transplant regime of immunosuppressive medication among the ever growing population of elderly kidney recipients. Methods. Q methodology was used to explore attitude profiles. Participants (>65 years) were asked to rankorder opinion statements on issues associated with (non-)adherence. The rankings were subject to by-person factor analysis, and the resulting factors were interpreted and described as attitudes. Results. T wenty-six elderly renal transplant recipients participated in the study. All passed the Mini-Mental State Examination. Two attitude profiles were found: (i) satisfied andeasy-going (attitude A),and(ii) reservedandconcerned (attitude B). Elderly patients with attitude A want to enjoy the new life following their kidney transplant, are not very concerned about having to recommence dialysis, now and then even forget their regime, and do not really worry about it. Elderly patients with attitude B feel more insecure about their kidney transplant, are fairly concerned over issues like rejection or going back on dialysis, and try to adapt their way of life to the regime. One-third of these elderly patients forget their medication at least once a month, but there was no difference between attitude groups. Conclusions. At titudes about the post-transplant regime differ among elderly patients, implying different needs for assistance, monitoring an d risk of non-adherence to the regime. The proportion of elderly patients who forget their medication is considerable, but may be much higher among those with mild and severe cognitive limitations.

Living donor kidney exchange programs offer incompatible donor-recipient pairs the opportunity to be transplanted. To increase the number of these transplants, we examined in our actual donor-recipient couples how to reach the maximum number of matches by using different chain lengths. We performed 20 match procedures in which we constructed four different chain lengths: two, up to three, up to four and unlimited. The actual inflow and outflow of donor-recipient couples for each run were taken into consideration in this analysis. The total number of matched pairs increased from 148 pairs for only two-way exchanges to 168 for three-way exchanges. When a chain length of 4 was allowed five extra couples could be matched over a period of 5 years. Unlimited chain length did not significantly affect the results. The optimal chain length for living donor kidney exchange programs is 3. Longer chains with their inherent logistic burden do not lead to significantly more transplants.

Kidney transplantations with living related and unrelated donors are the optimal option for patients with end-stage renal disease. For patients with a willing--but blood-type or HLA incompatible donor--a living-donor kidney exchange program could be an opportunity. In Asia, the United States and Europe, kidney exchange programs were developed under different conditions, with different exchange algorithms, and with different match results. The easiest way to organize a living-donor kidney exchange program is to enlist national or regional cooperation, initiated by an independent organization that is already responsible for the allocation of deceased donor organs. For logistic reasons, the optimal maximum chain length should be three pairs. To optimize cross-match procedures a central laboratory is recommended. Anonymity between the matched pairs depends on the culture and logistics of the various countries. For incompatible donor-recipient pairs who have been unsuccessful in finding suitable matches in an exchange program, domino-paired kidney transplantations triggered by Good Samaritan donors is the next alternative. To expand transplantations with living donors, we advise integrating such a program into a national exchange program under supervision of an independent allocation authority. If no Good Samaritan donors are available, an unbalanced kidney paired-exchange program with compatible and incompatible pairs is another strategy that merits future development.

In a growing number of transplant centers worldwide, altruistic donors are accepted to anonymously donate a kidney to a stranger. An important hesitation to expand these transplantation programs is the fear of evoking psychological distress in the altruistic donor after donation. To what extent this fear is justified has not yet been systematically investigated. In this study, 24 altruistic donors were interviewed on average 2 years after donation. Lifetime mental health history, current psychological complaints, satisfaction with and impact of the donation on well-being, motives for donation, communication with recipient and donation experience were assessed. Altruistic donors report a considerable positive impact of donation on psychological well-being, whereas negative impact was limited. Satisfaction with donation was very high. Although a history of a psychiatric diagnosis was ascertained in almost half of the donors, psychological complaints before and after donation were comparable to national average norm scores. Motives for donation were genuine and the experience of donation generally conformed to their expectations. In conclusion, living kidney donation to a stranger does not appear to exacerbate psychological complaints. Moreover, altruistic donors report considerable satisfaction and personal benefit. The exceptional gift of altruistic donors can contribute toward solving the current organ shortage issue.

Mesenchymal stem cells (MSCs) inhibit the proliferation of allo-activated lymphocytes. This effect is primarily dependent on the secretion of anti-inflammatory factors by MSCs and is enhanced under inflammatory conditions. MSCs, however, also produce factors that can potentially activate resting immune cells. Full understanding of the behavior of MSCs under inflammatory and noninflammatory conditions is crucial when clinical application of MSCs is considered. Human adipose tissue-derived MSCs were cultured with nonactivated peripheral blood mononuclear cells (PBMCs) and the activation, proliferation, and function of PBMCs were examined. Seven days of coculture with autologous or allogeneic MSCs significantly increased the proliferation of PBMCs (3-fold). This effect was observed in both direct and transwell coculture systems. MSCs cocultured with PBMCs showed increased mRNA expression of the proinflammatory mediators interleukin-6 (IL-6), IL-8, tumor necrosis factor-a, the growth factors basic fibroblast growth factor and vascular endothelial growth factor-alpha, and the anti-inflammatory factor indoleamine 2,3-dioxygenase. After removal of MSCs, PBMCs showed a spectacular further increase in proliferation, with a maximum of 25-fold after 7 days. This increase in proliferation was not seen when PBMCs were kept in the presence of MSCs. The proliferating fraction of PBMCs largely consisted of CD4(+) T-cells with high CD25 expression and the proportion of CD127(neg)FoxP3(+) regulatory T-cells significantly increased from 5.0% to 8.5% of total CD4(+) T-cells. The expanded T-cells demonstrated normal responses to mitogen or alloantigen stimulation. The CD25(positive) fraction of these cells had immunosuppressive capacity. In conclusion, MSCs can stimulate the activation and proliferation of resting T-cells and generate regulatory T-cells. These findings are important when MSCs are applied in the clinic.

Contains fulltext : 88436.pdf (Publisher’s version ) (Open Access) BACKGROUND: Transplantation is the only treatment offering long-term benefit to patients with chronic kidney failure. Live donor nephrectomy is performed on healthy individuals who do not receive direct therapeutic benefit of the procedure themselves. In order to guarantee the donor's safety, it is important to optimise the surgical approach. Recently we demonstrated the benefit of laparoscopic nephrectomy experienced by the donor. However, this method is characterised by higher in hospital costs, longer operating times and it requires a well-trained surgeon. The hand-assisted retroperitoneoscopic technique may be an alternative to a complete laparoscopic, transperitoneal approach. The peritoneum remains intact and the risk of visceral injuries is reduced. Hand-assistance results in a faster procedure and a significantly reduced operating time. The feasibility of this method has been demonstrated recently, but as to date there are no data available advocating the use of one technique above the other. METHODS/DESIGN: The HARP-trial is a multi-centre randomised controlled, single-blind trial. The study compares the hand-assisted retroperitoneoscopic approach with standard laparoscopic donor nephrectomy. The objective is to determine the best approach for live donor nephrectomy to optimise donor's safety and comfort while reducing donation related costs. DISCUSSION: This study will contribute to the evidence on any benefits of hand-assisted retroperitoneoscopic versus standard laparoscopic donor nephrectomy. TRIAL REGISTRATION: Dutch Trial Register NTR1433.

Background. Rabbit antithymocyte globulins (rATGs) are known to convert CD4(+) CD25(-) FoxP3(-) T cells from healthy individuals to CD4(+) CD25(+) FoxP3(+) T cells. In this study, we investigated the effect of rATG on the induction of regulatory T cells (Tregs) from blood cells of patients with end-stage renal disease who are candidates for transplantation and rATG-induction therapy. The induced Tregs were analyzed and compared with naturally occurring CD4(+) CD25(+) FoxP3(+) T cells. Methods. The CD25(-) T cells of pretransplant patients (n = 7) and healthy controls (n = 4) were stimulated with rATG or control rabbit immunoglobulins for 24 hr. The phenotype of induced Tregs was examined by flow cytometry, and their function was studied in the conventional suppression assay. Further characterization was performed by mRNA analyses. Results. After 24 hr, the percentage of CD4(+) CD25(+) FoxP3(+) CD127(-/low) T cells and CD8(+) CD25(+) FoxP3(-) CD127(+) T cells became higher in the rATG-treated samples compared with the rabbit immunoglobulin-treated samples (P < 0.01). The rATG-induced CD25(+) T cells, whether CD4(+) or CD8(+) inhibited the allogeneic responses of CD25(-/dim) effector T cells as vigorously as natural CD25(+) T cells. However, the proportion of FoxP3(+) within the top 2% rATG-induced CD4(+) CD25(+) T-cells was lower than within the natural CD4(+) CD25(+) T-cells (11% +/- 2% vs. 95% +/- 5%, P < 0.01). The mRNA-expression levels of interleukin-27, interleukin-10, interferon-gamma, perforin, and granzyme B were markedly higher compared with natural CD25(+) T-cells (all P = 0.03), whereas CTLA4 (P = 0.03), transforming growth factor-beta (P = 0.02), and ROR gamma t (P = 0.04) were lower. Conclusion. rATG allows the induction of Tregs from patient peripheral blood mononuclear cell in vitro. In comparison with natural Tregs, the rATG-induced Tregs are phenotypically distinct but have similar regulatory activities. rATG may beneficially contribute to the mechanisms that control alloreactivity.

Contains fulltext : 87280.pdf (Publisher’s version ) (Closed access) Long-term physical and psychosocial effects of laparoscopic and open kidney donation are ill defined. We performed long-term follow-up of 100 live kidney donors, who had been randomly assigned to mini-incision open donor nephrectomy (MIDN) or laparoscopic donor nephrectomy (LDN). Data included blood pressure, glomerular filtration rate, quality of life (SF-36), fatigue (MFI-20) and graft survival. After median follow-up of 6 years clinical and laboratory data were available for 47 donors (94%) in both groups; quality of life data for 35 donors (70%) in the MIDN group, and 37 donors (74%) in the LDN group. After 6 years, mean estimated glomerular filtration rates did not significantly differ between MIDN (75 mL/min) and LDN (76 mL/min, p = 0.39). Most dimensions of the SF-36 and MFI-20 did not significantly differ between groups at long-term follow-up, and most scores had returned to baseline. Twelve percent of the donors reported persistent complaints, but no major complications requiring surgical intervention. Five-year death-censored graft survival was 90% for LDN, and 85% for MIDN (p = 0.50). Long-term outcome of live kidney donation is excellent from the perspective of both the donor and the recipient. 01 november 2010

Objective During an uncomplicated pregnancy the conceptus is a semiallogeneic entity in which rejection is prevented by suppression of the maternal immune system. We hypothesized that this suppression is disturbed in patients with preeclampsia and that a maternal immune response to fetal (foreign/paternal) antigens in the fetal-maternal interface may be responsible for local inflammation, with subsequent endothelial dysfunction and systemic disease. Study Design Blood samples were obtained from 14 women with preeclampsia (cases), 14 gestational-age and parity-matched women with uncomplicated pregnancies (controls), and their partners. We determined the partner-specific cytotoxic T-lymphocyte precursor frequency (CTLpf) and the CTLpf directed to unrelated partners with uncomplicated pregnancies. We measured the CTLpf in peripheral blood mononuclear cells (PBMCs) from cases and controls using limited-dilution assays. In addition, proliferation was tested in a mixed-lymphocyte culture (MLR). Results The partner-specific CTLpf was significantly higher in cases compared with controls (median, 183 [15-338] vs 67 [9-232] per million PBMCs, P = .02). In contrast, in women with uncomplicated pregnancies, the partner-specific CTLpf was down-regulated compared with the CTLpf directed to an unrelated partner who fathered uncomplicated pregnancies ( P = .02). No difference was found in partner-specific MLR response between cases and controls. Conclusion These results suggest that women with preeclampsia have a higher cytotoxic T-cell response to paternal antigens compared with pregnant controls. This insufficiently suppressed immune response may eventually lead to the development of preeclampsia.

This issue's cover image depicts in vitro cell-contact between adipose-derived stromal cells (ASC) and PBMC, taken from Quaedackers et al. (pp. 3436–3446). In this article, the authors explore the contact-dependent effect of mesenchymal stromal cells on immune cells, and demonstrate that ASC exert immunomodulatory effects by inhibiting both CD8+ and CD4+ T cell responses.

Mesenchymal stromal cells regulate immune cell function via the secretion of soluble factors. Cell membrane interactions between these cell types may play an additional role. Here, we demonstrate that subpopulations of allo-activated T cells are capable of binding to human adipose-derived stromal cells (ASC). The bound T-cell population contained CD8+ T cells and was enriched for CD4-CD8- T cells, whereas the proportion of CD4+ T cells was decreased compared with the non-bound T-cell population. Bound CD4+ T cells had high proliferative activity and increased CD25 and FoxP3 expression. However, they also expressed CD127, excluding regulatory T-cell function. In CD8+ T cells, IL-2 sensitivity, as determined by the analysis of phosphorylated STAT5, was lower in the presence of ASC and even lower in bound cells. In contrast, IL-2-induced phosphorylated STAT5 levels were higher in bound CD4+ T cells than in non-bound CD4+ T cells. Additionally, pro-proliferative TGF-beta signalling via endoglin and SMAD1/5/8 phosphorylation was detected in bound CD4+ T cells. Even after prolonged co-culture with ASC, the activated phenotype of bound CD4+ T cells persisted. In conclusion, these results demonstrate that the binding of lymphocytes to ASC represents an immunomodulatory mechanism in which CD8+ T cells are inhibited in their responsiveness to pro-inflammatory stimuli and reactive CD4+ T cells are depleted from the immune response.

The shortage of deceased donor kidneys for transplantation has resulted in the expansion of living donation programs. A number of possibilities have been explored, since it became clear that donors do not need to be genetically related to their recipients. Apart from classical direct donation, other options such as paired exchange, list exchange, altruistic donation and domino paired exchange programs have been implemented. In the Netherlands, patients who cannot be transplanted with their potential living donor because of ABO blood group incompatibility or a positive crossmatch, have the option to participate in a national paired kidney exchange program. The practical issues related to this program are described. The 5-years experience with the Dutch kidney exchange program is very positive as, so far, 42% of the recipients included have been transplanted. Recommendations are given for a successful implementation of a common kidney exchange program of different transplantation centers focusing on the advantage of a central histocompatibility laboratory.

To assess whether regulatory T cells are present in rejecting human cardiac allografts, we performed functional analyses of graft lymphocytes (GLs) expanded from endomyocardial biopsies (EMB; n = 5) with histological signs of acute cellular rejection. The GL cultures were tested for their proliferative capacity and regulatory activity on allogeneic-stimulated peripheral blood mononuclear cells (PBMC) of the patient (ratio PBMC:GLs = 5:1). Three of these GL cultures were hyporesponsive to donor antigens and suppressed the antidonor proliferative T-cell response of PBMC, but not the anti-third-party response. Interestingly, it was the CD8(+) GL subset of these cultures that inhibited the antidonor response (65-91% inhibition of the proportion of proliferating cells); the CD4(+) GLs of the expanded GL cultures were not suppressive. In conclusion, CD8(+) GLs expanded from rejecting human cardiac allografts can exhibit donor-specific immune regulatory activities in vitro. We suggest that during acute cellular rejection, GLs may not only consist of graft-destructing effector T cells, but also of cells of the CD8(+) type with the potential to specifically inhibit antidonor immune reactivity.

Background. The small molecule drug CP-690,550 inhibits Janus kinase 3 at nanomolar concentrations and has recently been shown to prevent allograft rejection in rodents and nonhuman primates. Methods. As part of a phase I clinical trial, we investigated the effect of CP-690,550 after 29 days of 30 mg twice daily treatment at the cellular level in eight kidney transplant patients by studying ex vivo phosphorylation of STAT5 (P-STAT5), the key substrate of JAK3. Results. As determined by quantitative fluorescent western blotting, interleukin-2-induced P-STAT5 in YT cells was reduced by a median of 73% (P

Background. Laparoscopic donor nephrectomy (LDN) has become the preferred procedure for live donor nephrectomy. Most transplant surgeons are reluctant toward right-sided LDN (R-LDN) fearing short vessels and renal vein thrombosis. Methods. In our institution, selection of the appropriate kidney for donation was based on the same criteria that traditionally governed open donor nephrectomy. All intraoperative and postoperative data were prospectively recorded. Results. One hundred fifty-nine R-LDNs (56%) and 124 left-sided LDNs (1-LDN, 44%) were performed. Demographics did not significantly differ. Complications occurred in 10 (6%) vs. 23 (19%) procedures (R-LDN vs. L-LDN, P=0.002), resulting in 2 and 11 conversions, respectively. Right-sided kidney donation was the only independent preventative factor for complications in multivariate analysis (P=0.008, Odds ratio 0.33). R-LDN was associated with shorter operation time (mean 202 vs. 247 min, P

Background. In the search for mechanisms that can induce and maintain transplant tolerance, donor-specific CD4(+)CD25(bright) (+)Foxp3(+) regulatory T cells have been frequently mentioned. However, it remains to be demonstrated, whether these cells are generated after clinical transplantation. Methods. We prospectively analyzed the phenotype and function of peripheral regulatory CD4(+)CD25(bright+) T cells of 79 patients before, 3, 6, and 12 months after kidney transplantation. The immune regulatory capacities of CD4(+)CD25(bright+) T cells were assessed by their depletion from peripheral blood mononuclear cells and in co-culture with CD25(neg/dim) responder T-cells in the mixed lymphocyte reactions. Results. In the first year after transplantation, the number and proportion of CD4(+)CD25(bright+) T cells significantly decreased (P

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Only a decade ago, human immunodeficiency virus (HIV)-seropositivity was considered an absolute contraindication for organ transplantation. With the currently available experience, it is no longer justified to deny HIV-positive patients access to transplantation. To the best of our knowledge, we here present the longest surviving HIV-positive patient after renal transplantation. The follow-up period after renal transplantation in this HIV-positive female is now 13 yr and she is in good general condition with excellent renal function. Throughout her post-transplant follow-up, we encountered a number of problems that are illustrative of the HIV-positive patient.

From 535 endomyocardial biopsies (87 heart transplant recipients) 283 cell cultures could be generated. All cultures tested contained T lymphocytes and in most cases CD4 was the predominant phenotype at any time posttransplant. A significantly higher proportion of CD8-dominated cultures was found among cultures from biopsies without myocytolysis. In the first 3 months post transplant 57% of cultures showed cytotoxicity against both class I and class II mismatched donor major histocompatibility complex (MHC) antigens, changing to an incidence of 33% at greater than 90 days. This proved to be due to a significant decrease in the number of cultures with human leukocyte antigen class II-directed cytotoxicity. This study shows that early after transplantation a heart transplant is infiltrated with activated donor-specific cytotoxic T cells which recognize a broad spectrum of mismatched donor MHC antigens, and that in time this spectrum becomes more restricted.

BACKGROUND.: Living donor kidney exchange is now performed in several countries. However, no information is available on the practical problems inherent to these programs. Here, we describe our experiences with 276 couples enrolled in the Dutch program. METHODS.: Our protocol consists of five steps: registration, computerized matching, crossmatching, donor acceptation, and transplantation. We prospectively collected data of each step of the procedure. RESULTS.: Of the 276 registered pairs we created 183 computer-matched combinations. However, 62 of 183 recipients proved to have a positive crossmatch with their new donor, which was not predicted by the screening results of the recipient centers. Alternative solutions were found for 39 couples, resulting in a total of 160 new combinations with negative crossmatches. Thereafter, because of 22 individual clinical problems, the exchange procedure had to be discontinued for 51 couples while only for 19 of them alternative solutions were found. At the end of day, 128 patients had received exchange kidneys, 55 were transplanted outside the program, 59 are still on the crossover waitlist, and 34 had left the program for medical or psychological reasons. CONCLUSION.: A living donor kidney exchange program is a dynamic process. Many clinical hurdles and barriers are encountered that for a large part were not foreseen but should be taken into account when programs are initiated based on computer simulations. Success is dependent on a flexible organization able to create alternative solutions when problems arise. Centralized allocation and crossmatch procedures are instrumental in this respect.

The role of CD4(+) CD25(bright) regulatory T cells (Treg) in controlling alloreactivity is established, but little is known whether antigen-specific Treg are induced in fully immunosuppressed kidney transplant patients.The frequency and function of CD25(bright) T cells of nine stable kidney transplant patients before and 0.5-2 yr after transplantation were measured. Patients received triple therapy consisting of cyclosporine, mycophenolate mofetil and prednisone. To investigate the influence of transplantation and immunosuppression on Treg function, we compared their suppressive capacities pre- and post-transplantation using mixed lymphocyte reactions and kept the CD25(-/dim) effector T-cell (Teff) population constant.After transplantation, the percentage of CD4(+) CD25(bright) T cells significantly decreased from 8.5% pre-transplant to 6.9% post-transplant (median, p = 0.05). However, the lower percentage of post-transplant CD4(+) CD25(bright) T cells was not associated with reduced, but rather improved suppressor function of these cells. The proliferative response of pre-transplant Teff to donor-antigens was more profoundly suppressed by post-transplant Treg than by pre-transplant Treg (pre-transplant 18% vs. post-transplant 55% median, p = 0.03) and was comparable against third party antigens at a CD25(bright):CD25(-/dim) ratio of 1:20.In immunosuppressed kidney transplant patients, the donor-directed suppressive capacity of CD4(+) CD25(bright) regulatory T cells improved, which may contribute to the development of donor-specific hyporesponsiveness against the graft.