M-CSF and prostratin induced Mregs promote immune tolerance in transplanted mice through Arg-1 pathway.

OBJECTIVE: Regulatory macrophages (Mregs) are a group of heterogeneous macrophages. These cells could induce immunosuppressive effects through the expression of immune regulatory molecules and cytokines. METHODS: The differentiation of Mregs was induced by treating bone marrow cells with M-CSF and prostratin in vitro. The cell-phenotypes and immunosuppressive function were determined by flow cytometry. Rt-PCR was employed to assess the mechanisms of Mregs. Skin grafted mouse model was used for in vivo validation. RESULTS: Mregs induced by M-CSF + prostratin had a strong inhibitory effect on T cell proliferation and cytokines production. The phenotype of induced bone marrow cells changed towards Mregs. These Mregs could induce the differentiation of Tregs in vivo. Arg-1 expression in these cells were significantly upregulated. Inhibition of arginase (Arg) or arginine supplement significantly reversed the immunosuppressive function. In mice skin-grafted models, adoptive transfer of these Mregs significantly prolonged allograft survival. In mice models, Arg-1 expression significantly elevated on skin grafts cells and Tregs increased in graft tissues. CONCLUSIONS: We successfully developed a Mregs-inducing protocol with the combination of M-CSF and prostratin in vitro. M-CSF + prostratin induced Mregs prevented mice skin graft rejection through upregulating the expression Arg-1.

The Yin and Yang of Type 1 Regulatory T Cells: From Discovery to Clinical Application.

Regulatory T cells are essential players of peripheral tolerance and suppression of inflammatory immune responses. Type 1 regulatory T (Tr1) cells are FoxP3- regulatory T cells induced in the periphery under tolerogenic conditions. Tr1 cells are identified as LAG3+CD49b+ mature CD4+ T cells that promote peripheral tolerance through secretion of IL-10 and TGF-ß in addition to exerting perforin- and granzyme B-mediated cytotoxicity against myeloid cells. After the initial challenges of isolation were overcome by surface marker identification, ex vivo expansion of antigen-specific Tr1 cells in the presence of tolerogenic dendritic cells (DCs) and IL-10 paved the way for their use in clinical trials. With one Tr1-enriched cell therapy product already in a Phase I clinical trial in the context of allogeneic hematopoietic stem cell transplantation (allo-HSCT), Tr1 cell therapy demonstrates promising results so far in terms of efficacy and safety. In the current review, we identify developments in phenotypic and molecular characterization of Tr1 cells and discuss the potential of engineered Tr1-like cells for clinical applications of Tr1 cell therapies. More than 3 decades after their initial discovery, Tr1 cell therapy is now being used to prevent graft versus host disease (GvHD) in allo-HSCT and will be an alternative to immunosuppression to promote graft tolerance in solid organ transplantation in the near future.

Berberine Prolongs Mouse Heart Allograft Survival by Activating T Cell Apoptosis via the Mitochondrial Pathway.

Berberine, which is a traditional Chinese medicine can inhibit tumorigenesis by inducing tumor cell apoptosis. However, the immunoregulatory of effects berberine on T cells remains poorly understood. Here, we first examined whether berberine can prolong allograft survival by regulating the recruitment and function of T cells. Using a major histocompatibility complex complete mismatch mouse heterotopic cardiac transplantation model, we found that the administration of moderate doses (5 mg/kg) of berberine significantly prolonged heart allograft survival to 19 days and elicited no obvious berberine-related toxicity. Compared to that with normal saline treatment, berberine treatment decreased alloreactive T cells in recipient splenocytes and lymph node cells. It also inhibited the activation, proliferation, and function of alloreactive T cells. Most importantly, berberine treatment protected myocardial cells by decreasing CD4+ and CD8+ T cell infiltration and by inhibiting T cell function in allografts. In vivo and in vitro assays revealed that berberine treatment eliminated alloreactive T lymphocytes via the mitochondrial apoptosis pathway, which was validated by transcriptome sequencing. Taken together, we demonstrated that berberine prolongs allograft survival by inducing apoptosis of alloreactive T cells. Thus, our study provides more evidence supporting the potential use of berberine in translational medicine.

Suppressive effects of vitamin C-treated induced-regulatory T cells on heart allograft rejection under vitamin C-deficient or -sufficient conditions.

Foxp3 stability of vitamin C-treated induced-regulatory T cells (V-iTregs) is superior to that of conventional iTregs (C-iTregs). However, the role of V-iTregs in allograft rejection under vitamin C-deficient conditions, such as those seen in humans, remains unclear. We aimed to elucidate the role of vitamin C treatment on generation and maintenance of iTregs from gulo knockout (Gulo-KO) mice as well as wild type (WT) mice, and in vitro and in vivo suppressive effects of V-iTregs on heart allograft rejection in either Gulo-KO or WT recipient mice. Conversion efficiency of iTregs was similar between C- and V-iTregs in both WT and Gulo-KO mice. V-iTregs from WT or Gulo-KO mice showed better in vitro Foxp3 stability than C-iTregs, although there was no difference between WT V-iTregs and Gulo-KO V-iTregs. Furthermore, V-iTregs from WT or Gulo-KO mice suppressed in vitro T cell proliferation better than C-iTregs. Heterotrophic heart transplantation from BALB/c mice to WT or vitamin C-deficient Gulo-KO C57BL/6J mice was performed following adoptive transfer of C- or V-iTregs. V-iTregs as well as C-iTregs prolonged heart allograft survival in WT and Gulo-KO mice. However, there was no difference between the C- and V-iTreg groups. Supplementation of low- or high-dose vitamin C did not induce significant changes in heart allograft survival in Gulo-KO recipients that had received V-iTregs. In conclusion, V-iTregs do not exert better suppressive effects on heart allograft survival than C-iTregs in either WT or vitamin C-deficient recipients.

JAK3 inhibitor-based immunosuppression in allogeneic islet transplantation in cynomolgus monkeys.

Islet transplantation is efficacious to prevent severe hypoglycemia and glycemic liability of selected patients of type 1 diabetes. However, since calcineurin inhibitor (CNI) causes ß-cell and nephrotoxicity, alternative drug(s) with similar potency and safety profile to CNI will be highly desirable. Here we tested whether JAK3 inhibitor, tofacitinib could be used instead of tacrolimus in CIT07 immunosuppression regimen in cynomolgus nonhuman primate (NHP) model. Five independent streptozotocin (STZ)-induced diabetic monkeys were transplanted with MHC-mismatched allogeneic islets and three animals were further re-transplanted upon insufficient glycemic control or early islet graft rejection. After islet transplantation, blood glucose levels were quickly stabilized and maximal islet graft survival as measured by serum C-peptide concentration was >330, 98, >134, 31, or 22 days, respectively, after transplantation (median survival day; 98 days). Cellular and humoral immune responses were efficiently suppressed by JAK3 inhibitor-based immunosuppression during the follow-up periods. Although intermittent increases of the genome copy number of cynomolgus cytomegalovirus (CMV) were detected by quantitative real-time PCR analyses, serious infections or posttransplant lymphoproliferative disease (PTLD) was not found in all animals. Taken together, we have shown that JAK3 inhibitor could be used in replacement of tacrolimus in a highly translatable NHP islet transplantation model and these results suggest that JAK3 inhibitor will be potentially incorporated in human allogeneic islet transplantation.

Fluoroquinolones for the treatment of latent Mycobacterium tuberculosis infection in liver transplantation.

Solid organ transplantation (SOT) is the best treatment option for end-stage organ disease. Newer immunosuppressive agents have reduced the incidence of graft rejection but have increased the risk of infection, particularly due to the reactivation of latent infections due to opportunistic agents such as Mycobacterium tuberculosis. Active tuberculosis (TB) after SOT is a significant cause of morbidity and mortality. Most cases of posttransplant TB are secondary to reactivation of latent tuberculosis infection (LTBI) due to the effects of long-term immunosuppressive therapy. Risk minimization strategies have been developed to diagnose LTBI and initiate treatment prior to transplantation. Isoniazid with vitamin B6 supplementation is the treatment of choice. However, liver transplantation (LT) candidates and recipients have an increased risk of isoniazid-induced liver toxicity, leading to lower treatment completion rates than in other SOT populations. Fluoroquinolones (FQs) exhibit good in vitro antimycobacterial activity and a lower risk of drug-induced liver injury than isoniazid. In the present review, we highlight the disease burden posed by posttransplant TB and summarize the emerging clinical evidence supporting the use of FQs for the treatment of LTBI in LT recipients and candidates.

Amino acid and lipid profiles following pig-to-primate liver xenotransplantation.

As outcomes in clinical liver transplantation steadily improve, demand continues to exceed supply, leading to a substantial disparity in organ availability. The translation of porcine liver xenotransplantation (LXT) into a clinical reality aims to address this dilemma. Our laboratory has previously established an applicable model of α-1,3-galactosyltransferase knockout (GalT-KO) pig-to-primate LXT with continuous human coagulation factor infusion and costimulation blockade. This report aims to further investigate the post-LXT lipid and amino acid metabolism profile in our longest surviving recipients (25 and 29 days). Experimental samples and control samples, consisting of pre-transplant porcine and baboon serum and plasma, were analyzed for standard lipid profiles and for amino acid levels. Lipid profiles of LXT recipients remained stable following xenotransplantation compared to donor porcine baseline levels. Amino acid concentrations also remained similar to baseline controls, with the exception of a 3-fold increase in l-ornithine and more than a 10-fold decrease in l-arginine post-transplant when compared to both porcine and baboon baseline levels. The observed changes in l-arginine are consistent with prior studies investigating the effects of graft preservation injury following liver transplantation. These results indicate that the porcine liver can maintain most biochemical profiles stably post-operatively in baboons and suggest that arginine supplementation post-LXT may potentially be useful for further prolongation of xenograft survival.

Local interventions for actinic keratosis in organ transplant recipients: a systematic review.

BACKGROUND: Actinic keratosis (AK) in organ transplant recipients (OTRs) has a high risk of progressing to invasive squamous cell carcinoma of the skin. Thus, early and consequent treatment of AKs is warranted in OTRs. OBJECTIVES: To summarize the current evidence for nonsystemic treatments of AKs in OTRs. METHODS: We performed a systematic literature search in MEDLINE, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL) and hand-searched pertinent trial registers up to 22 August 2018. Randomized controlled trials (RCTs) evaluating nonsystemic interventions for AKs in OTRs were included. The risk of bias was estimated using the Cochrane Risk of Bias Tool. RESULTS: Of 663 records initially identified, eight RCTs with 242 OTRs were included in a qualitative synthesis. Most studies evaluated methyl aminolaevulinate photodynamic therapy (MAL-PDT), followed by ablative fractional laser (AFXL) and diclofenac sodium 3% in hyaluronic acid, imiquimod 5% cream and 5-fluorouracil 5% cream (5-FU). MAL-PDT showed the highest rates of participant complete clearance (40-76·4%), followed by imiquimod (27·5-62·1%), diclofenac (41%) and 5-FU (11%). Similar results were observed for lesion-specific clearance rates. Treatment with AFXL alone revealed low lesion clearance (5-31%). Local skin reactions were most intense in participants treated with a combination of AFXL and daylight MAL-PDT. There were no therapy-related transplant rejections or worsening of graft function in any trial. The overall risk of bias was high. CONCLUSIONS: Limited evidence is available for the treatment of AKs in OTRs. MAL-PDT is currently the best-studied intervention. Lesion-specific regimens may not be sufficient to achieve disease control. Field-directed regimens are preferable in this high-risk population.

Mechanism of Nucleoside Triphosphate Diphosphohydrolase-1-Associated Imbalance in Adenosine Diphosphate Degradation, B-Cell Activation, and Related Injury During Acute Antibody-Mediated Rejection.

OBJECTIVE: The objective of this study was to investigate the effect of nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) during acute antibody-mediated rejection (AMR). METHODS: NTPDase1 overexpression, NTPDase1 knockout, and wild-type nude mice skin graft models were used to induce acute AMR. NTPDase1 expression in B cells, NTPDase1 messenger RNA expression in skin grafts, extracellular adenosine diphosphate (ADP) concentration, B-cell volume and surface antigens expression, average platelet transport rate, and ultrastructure and apoptosis of skin graft cells were investigated. RESULTS: During acute AMR in nude mice, higher NTPDase1 expression caused lower extracellular ADP concentration, smaller increase in B-cell volume, and major histocompatibility complex II surface antigen expression, suggesting a negative correlation between them; higher NTPDase1 expression also caused slower average platelet transport rate and less severe skin graft injury, suggesting a negative correlation between them. Pretreatment with high-dose exogenous NTPDase1 inhibited platelet activation and protected skin grafts, but it resulted in prolonged bleeding time (by 51.4%) and prolonged coagulation time (by 44.1%). CONCLUSION: An NTPDase1-associated imbalance in extracellular ADP degradation may contribute to B-cell activation, platelet activation, and more severe skin graft injury in nude mice. Pretreatment with high-dose exogenous NTPDase1 effectively protected skin grafts in nude mice at 1 week, but it increased the risk of bleeding.

A membrane-type surfactant protein D (SP-D) suppresses macrophage-mediated cytotoxicity in swine endothelial cells.

OBJECTIVE: Surfactant protein D (SP-D), which is secreted mainly in the lung, is an oligometric C type lectin that promotes phagocytosis by binding to carbohydrates on microbial surfaces. SP-D can also bind SIRPα, leading to a decrease in cytokine production by monocytes/macrophages. In the present study, we examined the possibility that SP-D suppresses macrophage-mediated xenogeneic cytotoxicity, by creating a membrane-type SP-D. METHODS: The cDNA for the carbohydrate recognition domain (CRD) of human SP-D was switched to that of a membrane-type protein, collectin placenta 1 (CL-P1), with a Flag-tag. The cDNA of CD47 was prepared as a control. The suppressive function of the membrane-type protein of the hybrid molecule, CL-SP-D, to monocytes/macrophages was then studied and the results compared with that for CD47. RESULTS: The expression of Flag-tagged CL-SP-D on the transfected SECs and the SIRPα on monocyte-like cells, THP-1 cells, was confirmed by FACS using anti-Flag Ab and anti-CD172a, respectively. The molecular size of the hybrid protein was next assessed by western blot. While significant cytotoxicity against SEC was induced in differentiated THP-1 cells, CL-SP-D significantly reduced THP-1-mediated cytotoxicity. In addition, phosphorylated SHP-1 was clearly detected in SEC/CL-SP-D in western blots. Moreover, IL-10 production was upregulated and IL-1ß production was suppressed in the case of THP-1 and SEC/CL-SP-D, compared with naïve SEC. Next, the cytotoxicity caused by the in vitro generated macrophage was assessed under the same conditions as were used for THP-1. CL-SP-D also showed the significant down-regulation on the macrophage. In addition, changes in IL-10 production by the macrophage confirmed the results. CONCLUSIONS: These findings indicate that the membrane-type SP-D serve as an effective therapeutic strategy for inhibiting macrophage-mediated xenograft rejection in xenotransplantation.

Comprehensive assessment for serum treatment for single antigen test for detection of HLA antibodies.

The single antigen test is widely used in the field of transplantation to determine the specificity of HLA antibodies. It will be beneficial to standardize the procedure of the single antigen test among HLA laboratories. It is not uncommon that single antigen testing on native sera fails to detect antibodies with very high concentrations. It has been shown that cleavage products of activated complement components may mask strongly binding antibodies in single antigen testing. To overcome inhibition by the activated complement products, sera are pretreated with ethylenediaminetetraacetic acid (EDTA), dithiothreitol (DTT), or heat inactivation before single antigen testing. However, no studies have been published to systemically compare the impact of these treatments on single antigen testing. The aim of this study is to understand the different effects these treatments may have on single antigen test results. We found that mean fluorescence intensity (MFI) obtained from sera treated with EDTA and heat inactivation were nearly identical, while DTT treatment was less potent to remove the inhibition. In addition, sera dilution did not further increase MFI of antibodies after EDTA treatment. Our results provide guidance to choose a pretreatment reagent for single antigen testing, and to compare studies obtained from laboratories using different treatments.

Adjuvanted (AS03) A/H1N1 2009 Pandemic Influenza Vaccines and Solid Organ Transplant Rejection: Systematic Signal Evaluation and Lessons Learnt.

INTRODUCTION: We investigated a signal of solid organ transplant (SOT) rejection after immunisation with (AS03) A/H1N1 2009 pandemic influenza vaccines. METHODS: Potential immunological mechanisms were reviewed and quantitative analyses were conducted. The feasibility of pharmacoepidemiological studies was explored. RESULTS: Overall results, including data from a pharmacoepidemiological study, support the safety of adjuvanted (AS03) pandemic influenza vaccination in SOT recipients. The regulatory commitment to evaluate the signal through a stepwise investigation was closed in 2014. CONCLUSION: Lessons learned highlight the importance of investigating plausible biological mechanisms between vaccines and potentially associated adverse outcomes, and the importance of selecting appropriate study settings and designs for safety signal investigations.

The ligands of translocator protein inhibit human Th1 responses and the rejection of murine skin allografts.

The translocator protein (TSPO) ligands affected inflammatory and immune responses. However, the exact effects of TSPO ligands on Th1 responses in vitro and in vivo are still unclear. In the present study, we found that TSPO ligands, FGIN1-27 and Ro5-4864, suppressed the cytokine production in a dose-dependent manner by purified human CD4+ T-cells from peripheral blood mononuclear cells (PBMCs) after stimulation. TSPO ligands inhibited the production of interferon γ (IFN-γ) by memory CD4+ T-cells and the differentiation of naïve CD4+ T-cells into Th1 cells via suppressing the activity of the corresponding transcription factors as indicated by reduced expression of T-bet and down-regulation of STAT1, STAT4 and STAT5 phosphorylation. TSPO ligands suppressed cell proliferation and activation of CD4+ T-cells by the inhibition of TCR signal transduction including membrane proteins: Zap, Lck, Src; cytoplasm proteins: Plcγ1, Slp-76, ERK, JNK and the nucleoproteins: c-Jun and c-Fos. In addition, FGIN1-27 inhibited mixed lymphocyte reactions by human or murine cells. After the transplantation of allogeneic murine skin, injection of FGIN1-27 into mice prevented graft rejection by inhibition of cell infiltration and IFN-γ production. Taken together, our data suggest that TSPO ligands inhibit Th1 cell responses and might be novel therapeutic medicine for the treatment of autoimmune diseases and prevention of transplant rejection.

Toward Clinical use of the IgG Specific Enzymes IdeS and EndoS against Antibody-Mediated Diseases.

The endoglycosidase EndoS and the protease IdeS from the human pathogen Streptococcus pyogenes are immunomodulating enzymes hydrolyzing human IgG. IdeS cleaves IgG in the lower hinge region, while EndoS hydrolyzes the conserved N-linked glycan in the Fc region. Both enzymes are remarkably specific for human IgG that after hydrolysis loses most of its effector functions, such as binding to leukocytes and complement activation, all contributing to bacterial evasion of adaptive immunity. However, taken out of their infectious context, we and others have shown that IdeS and EndoS can alleviate autoimmune disease in a number of animal models of antibody-mediated disorders. In this chapter, we will briefly describe the discovery and characterization of these unique enzymes, present the findings from a number of animal models of autoimmunity where the enzymes have been tested, and outline the ongoing clinical testing of IdeS. Furthermore, we will discuss the rationale for further development of IdeS and EndoS into novel pharmaceuticals against diseases where IgG antibodies contribute to the pathology, including, but not restricted to, chronic and acute autoimmunity, transplant rejection, and antidrug antibody reactions.

Renal xenotransplantation: experimental progress and clinical prospects.

There are >100,000 patients waiting for kidney transplants in the United States and a vast need worldwide. Xenotransplantation, in the form of the transplantation of kidneys from genetically engineered pigs, offers the possibility of overcoming the chronic shortage of deceased and living human donors. These genetic manipulations can take the form of (i) knockout of pig genes that are responsible for the expression of antigens against which the primate (human or nonhuman primate) has natural "preformed" antibodies that bind and initiate complement-mediated destruction or (ii) the insertion of human transgenes that provide protection against the human complement, coagulation, or inflammatory responses. Between 1989 and 2015, pig kidney graft survival in nonhuman primates increased from 23 days to almost 10 months. There appear to be no clinically significant physiological incompatibilities in renal function between pigs and primates. The organ-source pigs will be housed in a biosecure environment, and thus the risk of transferring an exogenous potentially pathogenic microorganism will be less than that after allotransplantation. Although the risk associated with porcine endogenous retroviruses is considered small, techniques are now available whereby they could potentially be excluded from the pig. The US Food and Drug Administration suggests that xenotransplantation should be restricted to "patients with serious or life-threatening diseases for whom adequately safe and effective alternative therapies are not available." These might include those with (i) a high degree of allosensitization to human leukocyte antigens or (ii) rapid recurrence of primary disease in previous allografts. The potential psychosocial, regulatory, and legal aspects of clinical xenotransplantation are briefly discussed.

EDTA Treatment of Serum Unmasks Complement-Mediated Prozone Inhibition in Human Leukocyte Antigen Antibody Testing.

OBJECTIVES: Luminex-based single-antigen bead human leukocyte antigen (HLA) antibody testing is widely used to define HLA antibodies for transplant compatibility. False-negative results can occur with complement-mediated prozone inhibition. This study assessed the effect of EDTA on the assay background reactivity and fluctuations in antibody mean fluorescent intensity. METHODS: Serum specimens were retrospectively tested using Luminex-based single-antigen beads with and without EDTA. Treated and untreated serum samples were compared by two measures: changes in background reactivity and changes in HLA antibody strength after EDTA treatment. RESULTS: Ten pretransplant and 48 posttransplant specimens were identified: lung (22), heart (10), kidney (21), heart/lung (two), pancreas (one), small bowel (one), and liver (one). After EDTA treatment, weak antibodies (below 2,000 mean florescent intensity) demonstrated the largest fluctuations. Newly identified HLA antibodies were seen in 16% (8/49) of class I and 26% (15/57) of class II beads. EDTA treatment did not result in false-negative reactions compared with untreated serum. CONCLUSIONS: EDTA serum pretreatment mitigated complement-mediated prozone inhibition and improved accurate HLA antibody detection. The background reactivity and the false-negative rate of the assay appear unchanged.

Tracing Donor-MHC Class II Reactive B cells in Mouse Cardiac Transplantation: Delayed CTLA4-Ig Treatment Prevents Memory Alloreactive B-Cell Generation.

BACKGROUND: The dual role of B cells as drivers and suppressors of the immune responses have underscored the need to trace the fate of B cells recognizing donor major histocompatibility complex class I and class II after allograft transplantation. METHODS: In this study, we used donor class II tetramers to trace the fate of I-E-specific B cells after immunization with BALB/c spleen cells or cardiac transplantation, in naive or sensitized C57BL/6 recipients. We combined this approach with genetic lineage tracing of memory B cells in activation-induced cytidine deaminase regulated Cre transgenic mice crossed to the ROSA26-enhanced yellow fluorescent protein reporter mice to track endogenous I-E-specific memory B cell generation. RESULTS: Immunization with BALB/c splenocytes or heart transplantation induced an expansion and differentiation of I-E-specific B cells into germinal center B cells, whereas BALB/c heart transplantation into sensitized recipients induced the preferential differentiation into antibody-secreting cells. A 10.8-fold increase in the frequency of I-E-specific memory B cells was observed by day 42 postimmunization. Treatment with CTLA4-Ig starting on day 0 or day 7 postimmunization abrogated I-E-specific memory B cell generation and sensitized humoral responses, but not if treatment commenced on day 14. CONCLUSIONS: The majority of donor-specific memory B cells are generated between days 7 and 14 postimmunization, thus revealing a flexible timeframe whereby delayed CTLA4-Ig administration can inhibit sensitization and the generation of memory graft-reactive B cells.

Clinically Significant Drug Interaction Between Clotrimazole and Tacrolimus in Pancreas Transplant Recipients and Associated Risk of Allograft Rejection.

STUDY OBJECTIVE: To examine the clinical significance of clotrimazole troche discontinuation on tacrolimus trough levels and risk of allograft rejection after pancreas transplantation. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENTS: Sixty-five pancreas transplant recipients (simultaneous pancreas-kidney transplants [39 patients], pancreas after kidney transplants [4 patients], and pancreas transplant alone [22 patients]) who were discharged after transplantation receiving a maintenance immunosuppressive regimen of tacrolimus, mycophenolate, and prednisone, and a clotrimazole troche to prevent oral mucosal candidiasis; per protocol, the clotrimazole troche was discontinued at 3 months after transplantation. MEASUREMENTS AND MAIN RESULTS: Patients were followed for 1 year after transplantation. The primary outcome measure was the difference in tacrolimus trough level before and after discontinuation of the clotrimazole troche. The secondary outcome measure was the difference in tacrolimus trough level when patients were stratified by the cohort that had a documented rejection episode 3-12 months after transplantation (rejection group) and the cohort that did not experience a rejection episode (no-rejection group). The incidence of rejection was evaluated in relation to mean tacrolimus trough concentrations above or below a protocol-defined level of significance (6 ng/ml). For the primary outcome, the mean tacrolimus trough level before discontinuation of the clotrimazole troche was significantly higher than the mean trough level after discontinuation (mean ± SD 9.6 ± 3.0 ng/ml vs 7.1 ± 2.6 ng/ml, p = 0.000003). For the secondary outcome, the mean tacrolimus trough level difference before and after clotrimazole troche discontinuation remained significant in both the no-rejection group (9.5 ± 3.0 ng/ml vs 7.4 ± 2.4 ng/ml, p = 0.00007) and rejection group (10.9 ± 3.3 ng/ml vs 4.1 ± 2.5 ng/ml, p = 0.0008). Between groups, the mean tacrolimus serum trough level after clotrimazole troche discontinuation was lower in the rejection group (4.1 ± 2.5 ng/ml) than that in the no-rejection group (7.4 ± 2.4 ng/ml; p = 0.005). The mean tacrolimus trough level difference between before and after discontinuation was greater in the rejection group (6.8 ± 1.5 ng/ml) versus the no-rejection group (2.1 ± 3.8 ng/ml, p = 0.009). Tacrolimus trough levels below 6 ng/ml (19 patients) after clotrimazole troche discontinuation were associated with an increased incidence of rejection episodes within 3-12 months after transplantation (odds ratio 12, 95% confidence interval 1.24-115.91, p = 0.032) versus trough levels of 6 ng/ml or higher (46 patients). CONCLUSION: Clotrimazole troche discontinuation at 3 months after transplantation may cause significant tacrolimus trough level reductions. In addition, when trough levels are below 6 ng/ml, these fluctuations may contribute to the occurrence of allograft rejection.

Parathyroid Allotransplant With a New Technique: A Prospective Clinical Trial.

OBJECTIVES: Parathyroid allotransplant is a valuable alternative in treating permanent hypoparathyroidism. However, it is a difficult process that requires several trained staff and advanced laboratory equipment, which makes the costs high. Here, we identify a new parathyroid allotransplant technique. MATERIALS AND METHODS: After obtaining informed consent from patients, parathyroid cell suspensions obtained from 4 donors who had undergone a subtotal parathyroidectomy owing to chronic renal failure were transplanted in 10 patients with permanent hypoparathyroidism after short-term cell cultivation. Prednisolone were used as immunosuppressant for the first 10 days and discontinued thereafter. RESULTS: Allograft function was observed in 7 patients (70%) at a mean follow-up of 12 months. Daily oral calcium and vitamin D supplementations discontinued totally in 7 patients. No major or minor complication was observed. CONCLUSIONS: Our technique is simple, fast, and has a low cost, with a 70% success rate at a mean follow-up of 12 months. It requires few staff, minimal equipment, and short-term immunosuppressant use for maintenance. The technical developments of parathyroid allotransplant, as mentioned in this study, may be important in treating permanent hypoparathyroidism.