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Introduction: Patients undergoing on-pump cardiac surgery are at an increased risk of acute kidney injury. QPI-1002, a small interfering ribonucleic acid, is under clinical development for the prevention of acute kidney injury. The safety, tolerability, and pharmacokinetics of QPI-1002 was evaluated in this first-in-man, Phase 1 study of a small, interfering ribonucleic acid in patients at risk of acute kidney injury after on-pump cardiac surgery., Methods: In this phase 1 randomized, placebo-controlled dose-escalation study, a single i.v. dose of QPI-1002 was administered in subjects undergoing on-pump cardiac surgery. Subjects received placebo ( n  = 4), or QPI-1002 in increasing doses of 0.5 mg/kg ( n  = 3), 1.5 mg/kg ( n  = 3), 5 mg/kg ( n  = 3), and 10 mg/kg ( n  = 3)., Results: A total of 16 subjects were enrolled in the study. The average maximum concentration and area under the curve from the time of dosing to the last measurable concentration of QPI-1002 were generally dose proportional, indicating that exposure increased with increasing dose. The average mean residence time (mean residence time to the last measurable concentration) was 10 to 13 minutes in all 4 drug-dosing cohorts. Adverse events occurred at a similar rate in all study groups. Of the total 109 reported adverse events, the events were distributed as 26 in the placebo group and 21, 19, 24, and 19 in the QPI-1002 0.5, 1.5, 5.0, and 10.0 mg/kg groups, respectively. Eight of the 16 subjects experienced at least 1 serious adverse event: 4 (100%) in the placebo group and 4 (33.3%) in the combined QPI-1002 cohorts., Discussion: QPI-1002 was rapidly eliminated from plasma. QPI-1002 was safe and well tolerated across all dose groups. Overall, no dose-limiting toxicities or safety signals were observed in the study. Further development of QPI-1002 for prophylaxis of acute kidney injury is warranted.

In this review, we present (1) the scientific basis for the use of high-dose immunosuppression followed by autologous peripheral blood hematopoietic stem cell transplantation for newly diagnosed type 1 diabetes (T1D); (2) an update of the clinical and laboratory outcome of 20 patients transplanted at the University Hospital of the Ribeirão Preto Medical School, University of São Paulo, Brazil, and followed up to January/2008, including 4 relapses among 19 patients without previous ketoacidosis; (3) a commentary on criticisms to our article that appeared in four articles from the scientific literature; and (4) a discussion of the prospectives for cellular therapy for T1D.

Context: Type 1 diabetes mellitus (DM) results from a cell-mediated autoimmune attack against pancreatic beta cells. Previous animal and clinical studies suggest that moderate immunosuppression in newly diagnosed type 1 DM can prevent further loss of insulin production and can reduce insulin needs., Objective: To determine the safety and metabolic effects of high-dose immunosuppression followed by autologous nonmyeloablative hematopoietic stem cell transplantation (AHST) in newly diagnosed type 1 DM., Design, Setting, and Participants: A prospective phase 1/2 study of 15 patients with type 1 DM (aged 14-31 years) diagnosed within the previous 6 weeks by clinical findings and hyperglycemia and confirmed with positive antibodies against glutamic acid decarboxylase. Enrollment was November 2003-July 2006 with observation until February 2007 at the Bone Marrow Transplantation Unit of the School of Medicine of Ribeirão Preto, Ribeirão Preto, Brazil. Patients with previous diabetic ketoacidosis were excluded after the first patient with diabetic ketoacidosis failed to benefit from AHST. Hematopoietic stem cells were mobilized with cyclophosphamide (2.0 g/m2) and granulocyte colony-stimulating factor (10 microg/kg per day) and then collected from peripheral blood by leukapheresis and cryopreserved. The cells were injected intravenously after conditioning with cyclophosphamide (200 mg/kg) and rabbit antithymocyte globulin (4.5 mg/kg)., Main Outcome Measures: Morbidity and mortality from transplantation and temporal changes in exogenous insulin requirements (daily dose and duration of usage). Secondary end points: serum levels of hemoglobin A1c, C-peptide levels during the mixed-meal tolerance test, and anti-glutamic acid decarboxylase antibody titers measured before and at different times following AHST., Results: During a 7- to 36-month follow-up (mean 18.8), 14 patients became insulin-free (1 for 35 months, 4 for at least 21 months, 7 for at least 6 months; and 2 with late response were insulin-free for 1 and 5 months, respectively). Among those, 1 patient resumed insulin use 1 year after AHST. At 6 months after AHST, mean total area under the C-peptide response curve was significantly greater than the pretreatment values, and at 12 and 24 months it did not change. Anti-glutamic acid decarboxylase antibody levels decreased after 6 months and stabilized at 12 and 24 months. Serum levels of hemoglobin A(1c) were maintained at less than 7% in 13 of 14 patients. The only acute severe adverse effect was culture-negative bilateral pneumonia in 1 patient and late endocrine dysfunction (hypothyroidism or hypogonadism) in 2 others. There was no mortality., Conclusions: High-dose immunosuppression and AHST were performed with acceptable toxicity in a small number of patients with newly diagnosed type 1 DM. With AHST, beta cell function was increased in all but 1 patient and induced prolonged insulin independence in the majority of the patients.

A novel bioequivalence testing approach was used to determine intrasubject variability and switchability of two ciclosporin formulations, SangCya (test) and Neoral (reference). Twenty healthy volunteers were enrolled into a single-dose, randomized, open-label, 4-period, 2-sequence study with a crossover replicate design. Subject-by-formulation interaction variances were compared using a mixed effects linear model. Intrasubject variability for ln AUC(0-infinity) and ln C(max) of SangCya and Neoral were not significantly different. The 95% confidence intervals of the intrasubject variability of AUC(0-infinity) (0.94) and C(max) (1.28) as determined using the bootstrap nonparametric percentile method (n = 2,000) were below the individual bioequivalence limit estimated at 2.25. We concluded equivalent intrasubject variability of ciclosporin pharmacokinetics and switchability between SangCya and Neoral.

Background: Recently, peptides derived from the heavy chain of HLA-B2702 have been shown to modulate immune responses. In this study, we examined the use of these peptides for immunosuppression in a pig to mouse islet xenograft model., Methods: Purified porcine islets were transplanted in autoimmune (non-obese diabetic) and non-autoimmune (streptozotocin-injected CBA or C57/Bl6) diabetic mice. Various dosing regimens of HLA-derived peptides with and without antilymphocyte therapy were administered to recipient mice. Graft rejection was determined by daily serum glucose determinations, and, at selected time points, grafts were removed to demonstrate function and provide immunohistochemical examination., Results: HLA-derived peptides were demonstrated to prolong graft survival in both pretransplant and posttransplant treatment regimens. This effect was increased with concomitant antilymphocyte therapy., Conclusions: Further elucidation of the mechanism of action of these immunomodulatory peptides may help in the development of novel immunosuppressive protocols.

Post-transplantation lymphoproliferative disorders (PTLD) are a clinicopathologically heterogeneous group of lymphoid proliferations. The majority are of B-cell origin and associated with Epstein-Barr virus (EBV) infection. In contrast, the development of T-cell PTLD is much less common and EBV does not appear to be involved in pathogenesis. In this report we describe three patients who developed large granular lymphocyte (LGL) leukaemia after renal transplantation. These patients had clonal expansion of CD3+, CD8+, CD57+, CD56- LGL. We were unable to detect CMV antigen or find evidence for EBV or human T-cell leukaemia/lymphoma virus genome in the LGL from these patients. These data show that LGL leukaemia should be included as one of the types of T-cell proliferations which can occur post transplant.

Background: Treatment of fetal pancreas (FP) isografts with insulin-like growth factor-I greatly improves the rate of conversion to euglycemia in diabetic rats. Complete knowledge of other factors that may facilitate the engraftment and function of FP in vivo is still embryonic. Augmenter of liver regeneration (ALR) is a newly described polypeptide growth factor found in weanling rat livers. ALR has trophic effects on regenerating liver. We studied the effects of in situ administration of this agent on FP isografts in rats., Methods: Streptozotocin-diabetic Lewis rats (blood glucose > 300 mg/dl) received 16 FP isografts transplanted intramuscularly. ALR was delivered from day 1 through day 14, in doses of 40 or 400 ng/kg/d. Animals were followed for 3 months with serial weights and blood glucose monitoring. These animals were compared with those treated with vehicle alone., Results: Of the group treated with ALR at 40 ng/kg/day for 14 days, 89% (eight of nine) were euglycemic (P=0.0003). Of the group treated with ALR at 400 ng/kg/day for 14 days, 88% (seven of eight) were euglycemic (P=0.0007). Of the group treated with vehicle alone, none of the six were euglycemic. Euglycemia is defined here as glucose < 200 mg/dl for 3 days. Pathology of the intramuscular transplant site showed patches of islet tissue embedded in fat. These patches demonstrated insulin immunoreactivity., Conclusions: Diabetes was reversed in a significantly greater proportion of FP + ALR-treated recipients than those animals treated with vehicle alone. Local delivery of growth factors may be used as an adjunct to FP transplantation to improve the rate of success. This in situ model may be useful to further evaluate other soluble factors.

We report a case of adenovirus infection of the renal allograft in a combined kidney/pancreas transplant recipient. The clinical presentation was renal allograft failure, which eventually reversed. The pancreatic graft function remained stable. A renal biopsy showed massive tubular necrosis associated with a prominent granulomatous reaction. The process had a striking regional distribution within the kidney with the injury and inflammation limited to the outer medulla. Adenovirus type 11 was isolated from renal tissue by culture, and adenovirus was demonstrated by immunofluorescence and electron microscopy in the kidney biopsy. Immunosuppression may result in unusual patterns of response to infectious agents. This case demonstrated tropism of the adenovirus to only selected tubules within the kidney, with sparing of other organ function including, specifically, the pancreas allograft. The differential diagnosis of a granulomatous reaction in the transplant kidney must be expanded to include viral infection, in particular, adenovirus.

Previous reports from other investigators demonstrate prolongation of allogeneic heart graft survival and decrease in CTL responses in rats treated with a small synthetic peptide corresponding to residues 75-84 of the human HLA-B7-01 molecule (Allotrap 07R). We wished to determine the efficacy of these peptides in the highly immunogenic ACI > LEW and LEW > ACI small bowel transplant models. Animals were divided into treatment groups: I, none; II, Allotrap (20 mg/kg/day on Days 0-4); III, cyclosporine (CsA; 10 mg/kg/day on Days 0-4); IV, Allotrap + CsA (as in groups II and III); V, Allotrap (40 mg/kg/day every other day on Days -19 to 4); VI, Allotrap + CsA (as in groups III and V); VII, Allotrap + CsA (as in groups III and V, with Allotrap administered intragraft Days 0-4). The animals were sacrificed at the time of graft rejection (defined by dusky, necrotic stoma and increased stomal output). Peripheral blood, spleen, native bowel, and allograft intraepithelial and lamina propria lymphocytes were harvested and mixed lymphocyte culture (MLC) reactivity against self, donor, and third-party splenocytes was assessed. Statistical analysis was performed by ANOVA with Dunnett's t for multiple comparisons against a control as a post hoc test. We found a very slight, but significant prolongation of graft survival in with treatment protocol V for both strain combinations. In addition, MLC response of splenocytes to donor antigen was decreased with combined CsA and Allotrap, but not with Allotrap alone. We conclude that Allotrap decreases response to alloantigens, and slightly, but significantly prolongs graft survival in the hihgly immunogenic small bowel transplant model.

Transplantation of fetal pancreas (FP) is a potential treatment for diabetes mellitus. FP has remarkable proliferative capacity and may be induced to expand sufficiently to provide a functional beta cell mass in adult recipients. We have demonstrated that local delivery of recombinant insulin-like growth factor-I (IGF-I) onto FP isografts is sufficient to reverse streptozotocin-induced diabetes in animals receiving as few as 4 fetal pancreata. In this current study we investigated other regimens of IGF-I delivery in an attempt to define whether its effects on FP required local delivery or whether other, more clinically feasible, forms of treatment would suffice. In our model, diabetic Lewis rats received isografts of 16 FP into the anterior thigh intramuscular (IM) site. In the group of FP recipients treated with vehicle alone, no animals converted to euglycemia (0/8). When the IM site was pretreated locally with 14 days of continuous IGF-I administration (69 micrograms/kg per day) prior to FP transplantation, 100% of the recipients (10/10) became euglycemic with a mean interval from transplant to euglycemia of 35 +/- 15 days (P < 0.001 when compared to vehicle alone). No significant advantage over the vehicle alone group was gained either when the FP tissue was cultured for 48 hr in the presence of IGF-I (100 micrograms/ml) and then implanted (27% conversion to euglycemia, 3/11) or when FP isografts were treated with continuous subcutaneous delivery of IGF-I (69 micrograms/kg per day over 14 days) distant from the transplant site (0% conversion to euglycemia, 0/6). IGF-I increased the rate of conversion to euglycemia either when delivered locally to FP isografts or when delivered to the transplant bed prior to transplantation. This suggests an active role of the IGF-I-treated transplant bed in the success of FP transplantation.

Portal venous (PV) injection of alloantigen can result in tolerance. We have previously reported that this effect is abrogated by pretreatment with gadolinium (Gd), an element known to inhibit Kupffer cell phagocytosis. To further elucidate the role of Kupffer cells (KC) in PV tolerance, the present study examined the ability of KC to present alloantigen in vitro to syngeneic responder lymphocytes after in vivo PV administration of alloantigen with or without pretreatment with Gd. Wistar Furth (WF) rats were pretreated 24 hr prior to KC harvest with a PV injection of 1 x 10(7) allogeneic Lewis (LEW) rat lymphocytes (KC-L) or saline (KC-N). Another group received Gd intravenously 24 h prior to the PV injection of LEW cells (KC-L + Gd). KC were isolated from the WF rats using collagenase digestion and Percoll (90% pure by morphologic criteria and by monoclonal antibodies KU-1 and ED-2). Responder WF lymphocytes were cocultured with media alone, or with KC as prepared above, for 72 hr. KC-L demonstrated significant stimulation of the WF responders (P = 0.02 vs KC-N). Gd abrogated this stimulation (P = 0.04, KC-L vs KC-L + Gd) but not by nonspecific inhibition of the cocultures (KC-N vs KC-L + Gd, P > 0.05, no difference). This study demonstrates that KC can effectively present PV alloantigen for the activation of naive syngeneic T lymphocytes, thereby further supporting the hypothesis that KC play an integral role in the induction of PV tolerance by presentation of antigen to responder T cells.

The rat has been used as a model to study the significance of graft and host interactions in small bowel transplantation (SBTX). A mouse model of SBTX would allow investigators to apply the knowledge of the well-defined genetics in the mouse to this field of study. Therefore, we have developed a mouse model of heterotopic SBTX using syngeneic C57BL6/J mice. Animals were anesthetized with a combination of ketamine and xylazine. Donor animals underwent midline laparotomy, with isolation of a segment of bowel as an isograft for transplantation to a recipient animal. The bowel was flushed in situ prior to removal of the graft with a Carrel patch of aorta and portal vein. The recipient animal underwent midline laparotomy and preparation of its infrarenal aorta and inferior vena cava for end-to-side anastomosis of the graft with 10-0 nylon. After vascular reperfusion of the graft the ends of the isografted bowel were brought out as stomata. Successful grafts were later assessed for viability by laparotomy or histological examination at the time of sacrifice. Areas of technical difficulty in this model and issues that might improve the experimental results are discussed. This model should allow investigators to apply the well-defined genetics of the mouse to probe the challenging field of intestinal transplantation.