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This study reports a significant association between pretransplant serum IgG reactivity to apoptotic cells and late kidney allograft loss. See editorial by Chong and Kaplan on page 1477.

The authors evaluate the long‐term results of HLA‐mismatched kidney transplantation without maintenance immunosuppression in 10 subjects following combined kidney and bone marrow transplantation in comparison with 21 immunologically similar living donor kidney recipients who were treated with conventional immunosuppression.

The authors show that antibody‐mediated rejection is accompanied by the development of serum polyreactive antibodies that bind apoptotic cells and activate complement, potentially triggering C4d deposition in damaged graft tissues.

Antibody rejection is often accompanied by nondonor HLA specific antibodies (NDSA) and self‐reactive antibodies that develop alongside donor‐specific antibodies (DSA). To determine the source of these antibodies, we immortalized 107 B‐cell clones from a kidney transplant recipient with humoral rejection. Two of these clones reacted to HLA class I or MICA. Both clones were also reactive to self‐antigens and a lysate of a kidney cell line, hence revealing a pattern of polyreactivity. Monoclonality was verified by the identification of a single rearranged immunoglobulin heavy chain variable region (VH) sequence for each clone. By tracking their unique CDR3 sequence, we found that one such polyreactive clone was highly expanded in the patient blood, representing ∼0.2% of circulating B cells. The VH sequence of this clone showed evidence of somatic mutations that were consistent with its memory phenotype and its expansion. Lastly, the reactivity of the expanded polyreactive B‐cell clone was found in the patient serum at time of rejection. In conclusion, we provide here proof of principle at the clonal level that human antibodies can cross‐react to HLA and self. Our findings strongly suggest that polyreactive antibodies contribute to DSA, NDSA as well as autoantibodies, in transplant recipients.

An idiopathic capillary leak syndrome (‘engraftment syndrome’) often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10–16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68+MPO+mononuclear cells and CD3+CD8+T cells, the latter with a high proliferative index (Ki67+). B cells (CD20+) and CD4+T cells were not detectable, and NK cells were rare. XY FISH showed that CD45+cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti‐rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2–4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.

An idiopathic capillary leak syndrome (‘engraftment syndrome’) often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10–16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68+MPO+mononuclear cells and CD3+CD8+T cells, the latter with a high proliferative index (Ki67+). B cells (CD20+) and CD4+T cells were not detectable, and NK cells were rare. XY FISH showed that CD45+cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti-rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2–4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.

Five patients with end-stage kidney disease received combined kidney and bone marrow transplants from HLA haploidentical donors following nonmyeloablative conditioning to induce renal allograft tolerance. Immunosuppressive therapy was successfully discontinued in four patients with subsequent follow-up of 3 to more than 6 years. This allograft acceptance was accompanied by specific T-cell unresponsiveness to donor antigens. However, two of these four patients showed evidence of de novoantibodies reactive to donor antigens between 1 and 2 years posttransplant. These humoral responses were characterized by the presence of donor HLA-specific antibodies in the serum with or without the deposition of the complement molecule C4d in the graft. Immunofluorescence staining, ELISA assays and antibody profiling using protein microarrays demonstrated the co-development of auto- and alloantibodies in these two patients. These responses were preceded by elevated serum BAFF levels and coincided with B-cell reconstitution as revealed by a high frequency of transitional B cells in the periphery. To date, these B cell responses have not been associated with evidence of humoral rejection and their clinical significance is still unclear. Overall, our findings showed the development of B-cell allo- and autoimmunity in patients with T-cell tolerance to the donor graft.

Six patients with renal failure due to multiple myeloma (MM) received simultaneous kidney and bone marrow transplantation (BMT) from HLA-identical sibling donors following nonmyeloablative conditioning, including cyclophosphamide (CP), peritransplant antithymocyte globulin and thymic irradiation. Cyclosporine (CyA) was given for approximately 2 months posttransplant, followed by donor leukocyte infusions. All six patients accepted their kidney grafts long-term. Three patients lost detectable chimerism but accepted their kidney grafts off immunosuppression for 1.3 to >7 years. One such patient had strong antidonor cytotoxic T lymphocyte (CTL) responses in association with marrow rejection. Two patients achieved full donor chimerism, but resumed immunosuppression to treat graft-versus-host disease. Only one patient experienced rejection following CyA withdrawal. He responded to immunosuppression, which was later successfully withdrawn. The rejection episode was associated with antidonor Th reactivity. Patients showed CTL unresponsiveness to cultured donor renal tubular epithelial cells. Initially recovering T cells were memory cells and were enriched for CD4+CD25+ cells. Three patients are in sustained complete remissions of MM, despite loss of chimerism in two. Combined kidney/BMT with nonmyeloablative conditioning can achieve renal allograft tolerance and excellent myeloma responses, even in the presence of donor marrow rejection and antidonor alloresponses in vitro.

The recent availability of pigs homozygous for 1,3-galactosyltransferase gene knockout, and improved immunosuppressive regimens that prevent an elicited antibody response, are expected to contribute to significantly increased survival of pig organs transplanted into primates, bringing clinical trials of xenotransplantation closer. Patients highly sensitized to human leukocyte antigens, who may be precluded from obtaining a human donor organ, would be one group that might benefit from xenotransplantation. However, there have been few studies on whether there is cross-reactivity of anti-human leukocyte antigen antibodies with pig antigens. What data there are suggest that such cross-reactivity exists and that this may be detrimental to the outcome after transplantation of a pig organ. Neither is it known whether sensitization after a pig xenograft would preclude subsequent allotransplantation, although the data available suggest that this will not be the case. Further investigation on allo- and xenoantibody cross-reactivity is required.

NAD+‐modified carbon paste electrodes were anodically or cathodically pretreated. The influence of the electrode composition on the catalytic response for NADH oxidation after these pretreatments has been investigated. Potentiodynamic cycling for activation allows to reaching high catalytic response even with the paraffin‐richest electrode composition, which is the best configuration from a practical viewpoint. The results are in good agreement with a qualitative model for the carbon paste electrode that assumes the existence of surface sites in contact with the aqueous media and pasting liquid. Cathodic pretreatment also gives easier oxidation of NADH although this pretreatment did not produce the enhanced catalytic response as the percentage of pasting liquid increases.

Theeffect of long-term pharmacologic immunosuppression (PI) on anti-Gal1–3Gal (∝Gal) antibody (Ab) levels has not been determined previously in humans. In this study, we measured ∝Gal Ab levels by ELISA in 14 healthy volunteers (controls) and in 70 patients with grafts (kidney, heart, liver) who had received different combinations of PI (including cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, and steroids) for >3 months. There was great variation in Gal IgM (<80-fold) and IgG (<160-fold). There was no difference in Gal IgM or Gal IgG between any one group and any other. In kidney patients with either high (mean 68) or low (mean 6) panel-reactive alloantibodies, there was no difference in ∝Gal Ab level or serum cytotoxicity to pig cells. In vitro immunoadsorption of ∝Gal Ab from the serum did not change panel-reactive alloantibody positivity. Therapy with OKT3, a mouse product that might stimulate ∝Gal Ab production, led to no significant change in patient Ab levels. We conclude that long-term (>3 months) PI does not reduce ∝Gal Ab levels sufficiently to be of clinical value in xenotransplantation.

Zinc and indium were deposited from sulphate and chloride electrolytes onto aluminium electrodes under potentiostatic conditions. The role of the anion, pH, cation concentration, cathodic potential and agitation were investigated. The deposit morphology and composition were studied by SEM and EDX. Potentiodynamic and galvanostatic techniques were also applied for product characterization. Once a critical amount of Zn was deposited preferred In deposition began without agitation. But under rotation or at low cathodic potentials Zn2+ discharge became the prevalent reaction. The results support the earlier hypothesis of the preferential adsorption of Zn ions [1].

The present work is concerned with the study of the activation mechanism of Al in alloys produced by indium. The electrochemical behaviour of aluminium in NaCl solutions containing In 3+ ions and the dissolution of Al-In and In-Al alloys were studied using potentiostatic, galvanostatic and potentiodynamic techniques, complemented by SEM. It was concluded that the aluminium activation is obtained only when indium comes into a true metallic contact with aluminium within an active pit and in the presence of chloride ions. Polarization curves for dissolution of Al-In and In-Al alloys were compared. The results suggest that the initial step in the dissolution mechanism of the Al-In alloy can be interpreted through chloride ion adsorption on a surface In-Al alloy. This adsorption occurs at more electronegative potentials than that of pure aluminium, thus avoiding repassivation.

This work deals with the study of the cathodic and active behaviour of aluminium in acid chloride solutions containing indium and zinc ions. The cathodic behaviour was studied using potentiostatic and potentiodynamic techniques, complemented by SEM and EDX. During cathodization, preferential adsorption of zinc ions occurs, compared to that of H+ and In3+ ions. Once a critical amount of zinc is deposited, preferred indium deposition begins. The synergistic interaction between zinc and indium ions and aluminium leads to its activation in chloride media. This can be explained by displacement reactions that produce an indium accumulation and preferential zinc dissolution. This situation produces a new interface, quasi-free of Zn but rich in In, which favours Cl− ion adsorption at more negative potentials than aluminium, leading to its activation.

The kinetics of the potentiostatic electroreduction of different anodic layers produced on cadmium in Na2S containing alkaline solutions has been studied at 25°C. Two types of anodic layer were used: (i) layers produced in the potential range of CdS and Cd(OH)2 stability, and (ii) layers predominantly composed of CdS. The electroreduction kinetics for both layers can be explained reasonably well throughout the nucleation and growth processes under diffusion control.

The kinetics of the potentiostatic electroreduction of cadmium oxide layers on polycrystalline cadmium electrodes have been investigated in 0.01–1.0m NaOH solutions. The study was undertaken to determine the influence of passive film formation conditions on the electroreduction process of the anodically produced hydrous cadmium hydroxide-oxide layers. By properly adjusting the electroreduction conditions the cathodic potentiostatic current transients can be satisfactorily described by a nucleation and growth mechanism involving the participation of soluble Cd(II) and passivating anodic species. Experimental data were analysed by the application of non linear least squares fit routines. From the parametric identification procedure coherent potential dependencies of the corresponding fitting parameters as well as reasonable values of the physicochemical constants included in the reaction model, have been obtained. In this way it is possible to correlate kinetic data of the electroreduction process of the anodic oxide layers to make a discrimination between the different mechanistic contributions to this complex reaction involving several steps.

Abstract: Among the patients that might potentially benefit from the availability of xenografts are those in kidney failure who demonstrate high levels of antibody reactivity to panels of typing lymphocytes. Such individuals with high PRA (panel reactive antibody) are unlikely to receive a renal allograft because they are highly sensitized to the vast majority of potential donors. In addition, all humans have demonstrable levels of natural antibodies reactive to distantly related species such as the pig. If there were a correlation between PRA and levels of natural antibodies, then such patients would also be at greater risk for hyperacute rejection of xenografts. We have therefore examined, in a blinded fashion, the porcine lymphocyte reactivity of sera from PRA positive donors. Subsets of the 105 sera tested were grouped by PRA level and analyzed for levels of natural antibodies detectable by a complement‐dependent cytotoxicity assay on porcine lymphocytes. There was no significant difference in the range of titers of natural antibodies between subsets. Thus, there was no demonstrable correlation between levels of PRA and levels of natural antibodies to porcine lymphocytes.

Depolarization of the hydrogen evolution reaction on high purity polycrystalline cadmium electrodes in alkaline media (12?pH?14 and 5?T?55°C) produced by cathodization in the range of potential comprised between the Cd/Cd(OH)2 electrode potential and the net HER potential under solution stirring conditions has been studied. The depolarization effect depends on the perturbing potential programme and it is little affected by the alkaline cation in solution. Results are discussed in terms of three concurrent reactions, namely the electrochemical formation of Cd(OH)2 and soluble Cd(OH)3-, the HER and the electrocrystallization of cadmium renewing the fresh active sites for the HER, SEM micrographs of activated cadmium electrodes reveal a heterogeneous surface topography of the new cadmium layers.

Summary: A technique for the isolation of human intrahepatic bile ductular epithelium, and the establishment of primary cultures using a serum- and growth-factor-supplemented medium combined with a connective tissue substrata is described. Initial cell isolates and monolayer cultures display phenotypic characteristics of biliary epithelial cells (low molecular weight prekeratin positive; albumin, alphafetoprotein, and Factor VIII-related antigen negative). Ultrastructural features of the cultured cells show cell polarization with surface microvilli, numerous interepithelial junctional complexes and cytoplasmic intermediate prekeratin filaments.

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During anodization of Cd in a solution of low Na2S content, a complex cadmium oxide hydroxide and CdS layer is formed, whereas at high Na2S concentration, a CdS layer in the thickness range of a few monolayers is formed.

Different voltammetric methods have been used to investigate the anodization of Cd in NaOH solutions (0.01‐1 M, 25 °C), which is observed to produce a hydrous cadmium hydroxide‐cadmium oxide layer and soluble Cd species.