Alemtuzumab induction and tacrolimus monotherapy in pancreas transplantation: One- and two-year outcomes

BACKGROUND. Alemtuzumab (Campath-1H) induction with tacrolimus monotherapy has been shown to provide effective immunosuppression for kidney, liver, lung, and small bowel transplantation. This drug combination was evaluated in pancreas transplant recipients. METHODS. Sixty consecutive pancreas transplants (30 simultaneous pancreas-kidney, 20 pancreas after kidney, and 10 pancreas alone) were carried out under this protocol between July 2003 to January 2005. The mean follow-up was 22 months (range 17-33). RESULTS. One-year patient, pancreas, and kidney allograft survival were 95%, 93%, and 90%, respectively. With 22 months follow-up, patient, pancreas, and kidney survival were 94%, 89%, and 87%, respectively. The rejection rate was 30% (18/60), with four patients (7%) experiencing steroid-resistant rejection. Major infection occurred in three (5%) patients resulting in two (3.3%) deaths from disseminated histoplasmosis and a herpes virus infection. One patient with cryptococcal meningitis was successfully treated. Seven (11.7%) patients experienced cytomegalovirus infection, all of whom responded to treatment with ganciclovir. One (1.7%) case of polymorphic posttransplant lymphoproliferative disease was seen, which regressed with a temporary discontinuation of tacrolimus and high-dose ganciclovir. The mean serum creatinine of the 30 simultaneous pancreas-kidney transplants at one year posttransplant was 1.37±0.33 mg/ml. The preexisting creatinine in pancreas after kidney transplants was not adversely affected by this immunosuppressive protocol. CONCLUSION. A single dose of perioperative alemtuzumab followed by daily tacrolimus monotherapy provides effective immunosuppression for pancreas transplantation, but the optimal use of this drug combination is not yet clear. © 2006 Lippincott Williams & Wilkins, Inc

Neuroprotective activity of a new erythropoietin formulation with increased penetration in the central nervous system

Apart from its hematopoietic effect, erythropoietin (EPO) is a molecule with high neuroprotective potential. However, its prolonged application may cause serious adverse effects due to the erythropoiesis stimulation. Therefore, an EPO derivative with neuroprotective properties but low hematopoietic activity, designated as neuropoietin (rhNEPO), was developed in our lab using an alternative purification process of the recombinant human erythropoietic counterpart (rhEPO) produced in CHO cells [1]. The in vitro cytoprotective activity of rhNEPO on neural phenotype cells and its brain uptake from blood are herein analyzed.Fil: Etcheverrigaray, Marina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; ArgentinaFil: Ceaglio, Natalia Analia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; ArgentinaFil: Mattio, Mónica Cristina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; ArgentinaFil: Roggero, Marcos Enrique. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; ArgentinaFil: Amadeo, Ignacio. Zelltek S. A.; ArgentinaFil: Forno, Angela Guillermina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; ArgentinaFil: Perotti, Norma Maria. Zelltek S. A.; ArgentinaFil: Kratje, Ricardo Bertoldo. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Cultivos Celulares; Argentin

Alemtuzumab preconditioning with tacrolimus monotherapy - The impact of serial monitoring for donor-specific antibody

BACKGROUND. Antibody preconditioning with tacrolimus monotherapy has allowed many renal allograft recipients to be maintained on spaced weaning. METHODS. Of 279 renal allograft recipients transplanted between March 2003 and December 2004, 222 (80%) had spaced weaning (i.e., reduction of tacrolimus monotherapy dosing to every other day, three times a week, twice a week, or once a week) attempted. Routine monitoring for donor-specific antibody (DSA) was begun in September 2004. Mean follow-up is 34±6.5 months after transplantation and 26±8.1 months after the initiation of spaced weaning. RESULTS. One hundred and twenty-two (44%) patients remained on spaced weaning. One- and 2-year actual patient/graft survival was 99%/99%, and 97%/96%. Fifty-six (20%) patients experienced acute rejection after initiation of spaced weaning. One- and 2-year actual patient/graft survival was 100%/98%, and 94%/78%. Forty-two (15%) patients with stable renal function had spaced weaning stopped because of the development of DSA, which disappeared in 17 (40%). One- and 2-year actual patient and graft survival was 100% and 100%. CONCLUSION. Adult renal transplant recipients who are able to be maintained on spaced weaning have excellent outcomes. Patients with stable renal function who have reversal of weaning because of the development of DSA also have excellent outcomes. Routine monitoring for DSA may allow patients to avoid late rejection after spaced weaning. © 2008 Lippincott Williams & Wilkins, Inc

Functional Capacity of Shiga-Toxin Promoter Sequences in Eukaryotic Cells

Shiga toxins (Stx) are the main virulence factors in enterohemorrhagic Escherichia coli (EHEC) infections, causing diarrhea and hemolytic uremic syndrome (HUS). The genes encoding for Shiga toxin-2 (Stx2) are located in a bacteriophage. The toxin is formed by a single A subunit and five B subunits, each of which has its own promoter sequence. We have previously reported the expression of the B subunit within the eukaryotic environment, probably driven by their own promoter. The aim of this work was to evaluate the ability of the eukaryotic machinery to recognize stx2 sequences as eukaryotic-like promoters. Vero cells were transfected with a plasmid encoding Stx2 under its own promoter. The cytotoxic effect on these cells was similar to that observed upon incubation with purified Stx2. In addition, we showed that Stx2 expression in Stx2-insensitive BHK eukaryotic cells induced drastic morphological and cytoskeletal changes. In order to directly evaluate the capacity of the wild promoter sequences of the A and B subunits to drive protein expression in mammalian cells, GFP was cloned under eukaryotic-like putative promoter sequences. GFP expression was observed in 293T cells transfected with these constructions. These results show a novel and alternative way to synthesize Stx2 that could contribute to the global understanding of EHEC infections with immediate impact on the development of treatments or vaccines against HUSFil: Bentancor, Leticia Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Bilen, Marcos Fabian. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mejias, María Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Fernández Brando, Romina Jimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Panek, Cecilia Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Ramos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Fernández, Gabriela Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Isturiz, Martín Amadeo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Ghiringhelli, Pablo Daniel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Palermo, Marina Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentin

Cold heparinized lactated ringers with procaine (HeLP) preservation fluid in 266 living donor kidney transplantations

Since the 1960s simple inexpensive cold lactated Ringers with additives has been used for short-term cold preservation of kidneys from living donors. We performed 266 living donor kidney transplantations from January 22, 2003 to October 30, 2006. Donor allografts were recovered laparoscopically and flushed with cold heparin, lactated Ringer's and procaine (HeLP) solution. Warm and cold ischemic times were typically <45 min and <90 min, respectively. The mean follow up was 21.6±12.2 months. There was no delayed graft function. Actuarial 1-year patient and graft survival were 98.6% and 98.1%, respectively. The creatinine at 1 year was 1.46±0.51 mg/dL. The cumulative incidences of acute cellular rejection at 6, 12, 18, and 24 months were 3.0%, 7.1%, 10.2%, and 11.7%. There were no identifiable side effects attributed to the HeLP solution. This study documents the effectiveness of cold HeLP as a flushing and short-term preservation fluid for living donor kidney transplantation with excellent results and significant cost benefit because of its low cost. © 2007 Lippincott Williams & Wilkins, Inc

Antilymphoid antibody preconditioning and tacrolimus monotherapy for pediatric kidney transplantation

Objective: Heavy post-transplant immunosuppression may contribute to long-term immunosuppression dependence by subverting tolerogenic mechanisms; thus, we sought to determine if this undesirable consequence could be mitigated by pretransplant lymphoid depletion and minimalistic post-transplant monotherapy. Study design: Lymphoid depletion in 17 unselected pediatric recipients of live (n = 14) or deceased donor kidneys (n = 3) was accomplished with antithymocyte globulin (ATG) (n = 8) or alemtuzumab (n = 9). Tacrolimus was begun post-transplantation with subsequent lengthening of intervals between doses (spaced weaning). Maintenance immunosuppression, morbidity, graft function, and patient/graft survival were collated. Results: Steroids were added temporarily to treat rejection in two patients (both ATG subgroup) or to treat hemolytic anemia in two others. After 16 to 31 months (mean 22), patient and graft survival was 100% and 94%, respectively. The only graft loss was in a nonweaned noncompliant recipient. In the other 16, serum creatinine was 0.85 ± 0.35 mg/dL and creatinine clearance was 90.8 ± 22.1 mL/1.73 m2. All 16 patients are on monotherapy (15 tacrolimus, one sirolimus), and 14 receive every other day or 3 times per week doses. There were no wound or other infections. Two patients developed insulin-dependent diabetes. Conclusion: The strategy of lymphoid depletion and minimum post-transplant immunosuppression appears safe and effective for pediatric kidney recipients. © 2006 Elsevier Inc. All rights reserved

Tuning intermolecular charge transfer in donor-acceptor two-dimensional crystals on metal surfaces

Organic charge transfer (CT) compounds display a wide range of exotic electronic properties (charge-density wave stabilization, Peierls transitions, etc.) depending on the amount of charge transferred from the donor (D) to the acceptor (A) species. A complete exploration of the complex electronic phase diagrams for such compounds would thus require methods to systematically tune the amount of charge exchanged in the CT process. This has proven however challenging in the past: chemical functionalization of the constituent molecules can also affect the packing of the molecular units in the crystal, whereas changing D:A stoichiometry is often not possible in the bulk. Interestingly, it was recently found that multiple stoichiometries can actually be achieved by codeposition of different amounts of D and A molecules on metal surfaces. The question, however, of whether CT processes between D and A molecules can be tuned with the D:A ratio in such mixtures has not yet been studied, and it is no trivial matter, since competing CT processes between the metal surface and the organic adsorbates might hinder interadsorbate charge transfer. Here we demonstrate that the CT process from the organic donor tetrathiafulvalene (TTF) to the acceptor tetracyanoquino-p-dimethane (TCNQ) can be tuned with exquisite accuracy (∼0.1 e) by controlling the stoichiometry of D:A cocrystals deposited on Ag(111). This control opens new avenues to explore the complex phase diagrams of organic CT compounds and to tailor their electronic properties.The authors acknowledge financial support from the Spanish Ministry for Economy and Competitiveness (Grants FIS2012-33011, FIS2015-67367-C2-1-P, FIS2013-42002-R, FIS2016-77889-R, CTQ2013-43698-P, CTQ2016-76061-P), the regional government of Comunidad de Madrid (Grants S2009/MAT1726 and S2013/MIT-3007), Universidad Autónoma de Madrid (UAM/48) and IMDEA Nanoscience. L.F. acknowledges financial support from MIUR (PRIN-2010BNZ3F2, Project DESCARTES), S.D.-T. acknowledges the ‘“Ramón y Cajal”’ program of the MINECO (RYC-2010-07019), and the María de Maeztu Programme for Units of Excellence in R&D of the MINECO (MDM-2014-0377)