Factors predicting kidney delayed graft function among recipients of simultaneous liver-kidney transplantation: A single-center experience.

BACKGROUND: Kidney delayed graft function (kDGF) remains a challenging problem following simultaneous liver and kidney transplantation (SLKT) with a reported incidence up to 40%. Given the scarcity of renal allografts, it is crucial to minimize the development of kDGF among SLKT recipients to improve patient and graft outcomes. We sought to assess the role of preoperative recipient and donor/graft factors on developing kDGF among recipients of SLKT. METHODS: A retrospective review of 194 patients who received SLKT in the period from January 2004 to March 2017 in a single center was performed to assess the effect of preoperative factors on the development of kDGF. RESULTS: Kidney delayed graft function was observed in 95 patients (49%). Multivariate analysis revealed that donor history of hypertension, cold static preservation of kidney grafts [versus using hypothermic pulsatile machine perfusion (HPMP)], donor final creatinine, physiologic MELD, and duration of delay of kidney transplantation after liver transplantation were significant independent predictors for kDGF. kDGF is associated with worse graft function and patient and graft survival. CONCLUSIONS: Kidney delayed graft function has detrimental effects on graft function and graft survival. Understanding the risks and combining careful perioperative patient management, proper recipient selection and donor matching, and graft preservation using HPMP would decrease kDGF among SLKT recipients.

Search for muon neutrino and antineutrino disappearance in MiniBooNE.

The MiniBooNE Collaboration reports a search for nu_{micro} and nu[over]_{micro} disappearance in the Deltam;{2} region of 0.5-40 eV;{2}. These measurements are important for constraining models with extra types of neutrinos, extra dimensions, and CPT violation. Fits to the shape of the nu_{micro} and nu[over]_{micro} energy spectra reveal no evidence for disappearance at the 90% confidence level (C.L.) in either mode. The test of nu[over]_{micro} disappearance probes a region below Deltam;{2} = 40 eV;{2} never explored before.

Measurement of the ratio of the numu charged-current single-pion production to quasielastic scattering with a 0.8 GeV neutrino beam on mineral oil.

Using high statistics samples of charged-current numu interactions, the MiniBooNE [corrected] Collaboration reports a measurement of the single-charged-pion production to quasielastic cross section ratio on mineral oil (CH2), both with and without corrections for hadron reinteractions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV

Measurement of numicro and nue events in an off-axis horn-focused neutrino beam.

We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3 degrees) with respect to the NuMI beam axis. Samples of charged-current quasielastic numicro and nue interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.

Unexplained excess of electronlike events from a 1-GeV neutrino beam.

The MiniBooNE Collaboration observes unexplained electronlike events in the reconstructed neutrino energy range from 200 to 475 MeV. With 6.46x10;{20} protons on target, 544 electronlike events are observed in this energy range, compared to an expectation of 415.2+/-43.4 events, corresponding to an excess of 128.8+/-20.4+/-38.3 events. The shape of the excess in several kinematic variables is consistent with being due to either nu_{e} and nu[over ]_{e} charged-current scattering or nu_{mu} neutral-current scattering with a photon in the final state. No significant excess of events is observed in the reconstructed neutrino energy range from 475 to 1250 MeV, where 408 events are observed compared to an expectation of 385.9+/-35.7 events.

Measurement of muon neutrino quasielastic scattering on carbon.

The observation of neutrino oscillations is clear evidence for physics beyond the standard model. To make precise measurements of this phenomenon, neutrino oscillation experiments, including MiniBooNE, require an accurate description of neutrino charged current quasielastic (CCQE) cross sections to predict signal samples. Using a high-statistics sample of nu_(mu) CCQE events, MiniBooNE finds that a simple Fermi gas model, with appropriate adjustments, accurately characterizes the CCQE events observed in a carbon-based detector. The extracted parameters include an effective axial mass, M_(A)(eff)=1.23+/-0.20 GeV, that describes the four-momentum dependence of the axial-vector form factor of the nucleon, and a Pauli-suppression parameter, kappa=1.019+/-0.011. Such a modified Fermi gas model may also be used by future accelerator-based experiments measuring neutrino oscillations on nuclear targets.

Search for electron neutrino appearance at the Delta m2 approximately 1 eV2 scale.

The MiniBooNE Collaboration reports first results of a search for nu e appearance in a nu mu beam. With two largely independent analyses, we observe no significant excess of events above the background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two-neutrino appearance-only oscillation model.

Comparison of IgE and IgG antibody-dependent cytotoxicity in vitro and in a SCID mouse xenograft model of ovarian carcinoma.

Allergic reactions are mediated by IgE antibodies bound to high-affinity receptors on mast cells in peripheral tissues and are characterized by their immediacy and hypersensitivity. These properties could also be advantageous in immunotherapy against cancer growth in peripheral tissues. We have constructed chimeric IgE and IgG1 antibodies with murine V regions and human C regions corresponding to the MOv18 monoclonal antibody against the human ovarian tumor-associated antigen, folate binding protein. The antibodies exhibited the expected binding affinities for antigen and Fc receptors, and effector activities with human basophils and platelets in vitro. The protective activities of MOv18-IgE and MOv18-IgG1 were compared in a SCID mouse xenograft model of ovarian carcinoma. The beneficial effects of MOv18-IgE were greater and of longer duration than those of MOv18-IgG1. Our results suggest that the allergic reaction could be harnessed for the suppression of ovarian tumors.

Short-term glucocorticoid administration decreases both hypothalamic and pituitary galanin synthesis in the adult male rat.

Galanin (GAL) is a peptide that has been implicated in the regulation of the growth axis. It is generally accepted that GAL can increase serum growth hormone (GH) levels, although the underlying mechanism for this increase is unknown. It is well known that long-term glucocorticoid treatment alters in vivo GH secretion, since there is a decrease in serum GH in response to stimuli. It has previously been shown in our laboratory that administration of GAL can overcome the effects of glucocorticoid administration on GH secretion. The aim of the present study was to determine the effects of long-term glucocorticoid administration on the regulation of hypothalamic and pituitary GAL mRNA levels. Adult male rats were treated for 72 hours with the synthetic glucocorticoid dexamethasone ([DEX] 40 microg/kg/d intraperitoneal injections). RNase protection assays were performed on both the hypothalamus and pituitary for the presence of GAL mRNA. As expected, DEX significantly decreased somatic growth, as evidenced by a decrease (50%) in the weight gain of glucocorticoid-treated versus control animals. It was also demonstrated that in both the hypothalamus and pituitary, glucocorticoid treatment reduced the level of GAL mRNA (to 11% and 6.5%, respectively) compared with the control condition. We conclude that the decrease in GAL mRNA may lead to a decrease in GAL secretion, which in turn may be involved in the glucocorticoid-induced inhibition of GH secretion.

Safety and immunogenicity of HIV-1 DNA constructs in chimpanzees.

A global effort to control the HIV epidemic is likely to rely heavily on immunization strategies. As our closest genetic relative, the chimpanzee provides the most important model for preclinical safety and immunogenicity studies. We have immunized adult, pregnant and infant chimpanzees with our plasmid vaccines. We have found these vaccines to be safe and well tolerated in all of these groups. The same vaccines have induced both humoral and cellular immunity in each instance.

First human trial of a DNA-based vaccine for treatment of human immunodeficiency virus type 1 infection: safety and host response.

A DNA-based vaccine containing human immunodeficiency virus type 1 (HIV-1) env and rev genes was tested for safety and host immune response in 15 asymptomatic HIV-infected patients who were not using antiviral drugs and who had CD4+ lymphocyte counts of > or = 500 per microliter of blood. Successive groups received three doses of vaccine (30, 100, or 300 microg) at 10-week intervals in a dose-escalation trial. Vaccine administration induced no local or systemic reactions, and no laboratory abnormalities were detected. Specifically, no patient developed anti-DNA antibody or muscle enzyme elevations. No consistent change occurred in CD4 or CD8 lymphocyte counts or in plasma HIV concentration. Antibody against gp120 increased in individual patients in the 100- and 300-/microg groups. Some increases were noted in cytotoxic T lymphocyte activity against gp160-bearing targets and in lymphocyte proliferative activity. The safety and potential immunogenicity of an HIV-directed DNA-based vaccine was demonstrated, a finding that should encourage further studies.

DNA vaccination as anti-human immunodeficiency virus immunotherapy in infected chimpanzees.

The role of the immune response in controlling human immunodeficiency virus type 1 (HIV-1) replication is controversial. Immunotherapeutic strategies that have the ability to broaden immune responses might play a role in slowing disease progression. DNA immunization was studied as immunotherapy in infected chimpanzees. Two HIV-1-infected chimpanzees were vaccinated with DNA plasmid vaccines, one with plasmid pCMN160, which expresses the envelope glycoprotein of HIV-1MN and rev, and the other with a control plasmid. The chimpanzee immunized with pCMN160 demonstrated enhanced humoral responses. Virus load was monitored. Virus load in the chimpanzee receiving pCMN160 decreased at week 20 and has remained at background levels. The control chimpanzee was subsequently vaccinated with pCMN160. After immunization, the antibody responses increased and, as in the first animal, the virus load decreased. These results indicate the potential of the immune response to have a direct impact on HIV-1 replication in chimpanzees.

Chimeric bispecific OC/TR monoclonal antibody mediates lysis of tumor cells expressing the folate-binding protein (MOv18) and displays decreased immunogenicity in patients.

The bispecific OC/TR monoclonal antibody (mAb) cross-links the CD3 molecule on T cells with the human folate-binding protein (FBP), which is highly expressed on nonmucinous ovarian carcinomas. Clinical trials of patients with ovarian carcinoma with the OC/TR mAb have shown some complete and partial responses. Most patients developed human anti-murine immunoglobulin antibodies (HAMA), which can inhibit OC/TR mAb-mediated lysis. We generated a chimeric version of the OC/TR mAb to decrease the immunogenicity of the OC/TR mAb and to allow more extended treatment schedules. Sp2/0 myeloma cells were transfected with chimeric heavy- and light-chain genes encoding the anti-CD3 mAb and the MOv18 mAb, respectively, which are reactive with FBP. The resulting cell line produced 80 micrograms/ml of total immunoglobulin G (IgG), of which 11.5% was the functionally active chimeric OC/TR mAb. Chimeric OC/TR F(ab')2 fragments mediated lysis of IGROV-1 ovarian carcinoma cells by human T cells at antibody concentrations of > or = 1 pg/ml. Specific lysis was still detectable at an effector-to-target cell ratio as low as 0.4. Two patients with ovarian carcinoma treated with F(ab')2 fragments of the murine OC/TR developed distinct HAMA titers, which were mainly anti-idiotypic and only partly directed against the murine antibody constant regions. However, of the two patients that were treated with the F(ab')2 fragments of the chimeric OC/TR mAb, only one developed a low transient HAMA response just above background level. In conclusion, the generation of chimeric OC/TR may allow more extended clinical studies of bispecific mAb-mediated immunotherapy of ovarian carcinoma.

Nucleic acid immunization of chimpanzees as a prophylactic/immunotherapeutic vaccination model for HIV-1: prelude to a clinical trial.

Vaccine development strategies have often utilized recombinant envelope glycoproteins which usually generate strong humoral immune responses but which do not generate strong cytotoxic T lymphocytes (CTL). A recent novel experimental vaccination approach involves the technology known as nucleic acid immunization in which DNA plasmids expressing a gene of interest is injected intramuscularly in experimental animals. These expressed proteins then are presented to the immune system with the subsequent development of strong antibody and cellular (particularly CTL) immune responses. These types of immune responses have been elicited in rodents as well as nonhuman primates including chimpanzees. Results from studies on nucleic acid immunization of HIV-1 infected chimpanzees with envelope glycoprotein expressing constructs indicated that this method was able to decrease substantially HIV-1 viral load in these chimpanzees. These data are useful for the development and implementation of human phase I clinical trials with HIV constructs expressing various genes from the HIV-1 genome.

Protection of chimpanzees from high-dose heterologous HIV-1 challenge by DNA vaccination.

Novel approaches for the generation of more effective vaccines for HIV-1 are of significant importance. In this report we analyze the immunogenicity and efficacy of an HIV-1 DNA vaccine encoding env, rev and gag/pol in a chimpanzee model system. The immunized animals developed specific cellular and humoral immune responses. Animals were challenged with a heterologous chimpanzee titered stock of HIV-1 SF2 virus and followed for 48 weeks after challenge. Polymerase chain reaction coupled with reverse transcription (RT-PCR) results indicated infection in the control animal, whereas those animals vaccinated with the DNA constructs were protected from the establishment of infection. These studies serve as an important benchmark for the use of DNA vaccine technology for the production of protective immune responses.

Generation of chimeric bispecific G250/anti-CD3 monoclonal antibody, a tool to combat renal cell carcinoma.

The monoclonal antibody (MAb) G250 binds to a tumour-associated antigen, expressed in renal cell carcinoma (RCC), which has been demonstrated to be a suitable target for antibody-mediated immunotherapy. A bispecific antibody having both G250 and anti-CD3 specificity can cross-link G250 antigen-expressing RCC target cells with T cells and can mediate lysis of such targets. Therapy studies with murine antibodies are limited by immune responses to the antibodies injected (HAMA response), which can be decreased by using chimeric antibodies. We generated a chimeric bispecific G250/anti CD3 MAb by transfecting chimeric genes of heavy and light chains for both the G250 MAb and the anti-CD3 MAb into a myeloma cell line. Cytotoxicity assays revealed that the chimeric bispecific MAb was capable of mediating lysis of RCC cell lines by cloned human CD8+T cells or by IL-2-stimulated peripheral blood lymphocytes (PBLs). Lysis mediated by the MAb was specific for target cells that expressed the G250 antigen and was effective at concentrations as low as 0.01 microgram ml-1. The chimeric bispecific G250/anti-CD3 MAb produced may be an effective adjuvant to the currently used IL-2-based therapy of advanced renal cell arcinoma.

In vivo protective anti-HIV immune responses in non-human primates through DNA immunization.

An effective immune response involves the specific recognition of and elimination of an infectious organism at multiple levels. In this context DNA immunization can present functional antigenic proteins to the host for recognition by all arms of the immune system, yet provides the opportunity to delete any genes of the infectious organism which code for antigens or pieces of antigens that may have deleterious effects. Our group has developed the use of nucleic acid immunization as a possible method of vaccination against Human immunodeficiency virus type 1 (HIV-1) [1,2,3,10,11,12]. Sera from non-human primates immunized with DNA vectors that express the envelope proteins from HIV-1 contain antibodies specific to the HIV-1 envelope. These sera also neutralize HIV-1 infection in vitro and inhibit cell to cell infection in tissue culture. Analysis of cellular responses is equally encouraging. T cell proliferation as well as cytotoxic T cell lysis of relevant env expressing target cells were observed. In addition, evidence that DNA vaccines are capable of inducing a protective response against live virus was demonstrated using a chimeric SIV/HIV (SHIV) challenge in vaccinated cynomologous macaques. We found that nucleic acid vaccination induced protection from challenge in one out of four immunized cynomolgus macaques and viral load was lower in the vaccinated group of animals versus the control group of animals. These data encouraged us to analyze this vaccination technique in chimpanzees, the most closely related animal species to man. We observed the induction of both cellular and humoral immune responses with a DNA vaccine in chimpanzees. These studies demonstrate the utility of this technology to induce relevant immune responses in primates which may ultimately lead to effective vaccines.

Facilitated DNA inoculation induces anti-HIV-1 immunity in vivo.

Vaccine design against HIV-1 is complicated both by the latent aspects of lentiviral infection and the diversity of the virus. The type of vaccine approach used is therefore likely to be critically important. In general, vaccination strategies have relied on the use of live attenuated material or inactivated/subunit preparations as specific immunogens. Each of these methodologies has advantages and disadvantages in terms of the elicitation of broad cellular and humoral immune responses. Although most success has been achieved with live attenuated vaccines, there is a conceptual safety concern associated with the use of these vaccines for the prevention of human infections. In contrast, subunit or killed vaccine preparations enjoy advantages in preparation and conceptual safety; however, their ability to elicit broad immunity is more limited. In theory, inoculation of a plasmid DNA that supports in vivo expression of proteins, and therefore presentation of the processed protein antigen to the immune system, could be used to combine the features of a subunit vaccine and a live attenuated vaccine. We have designed a strategy for intramuscular DNA inoculation to elicit humoral and cellular immune responses against expressed HIV antigens. Uptake and expression are significantly enhanced if DNA is administered in conjunction with the facilitating agent bupivacaine-HCl. Using this technique we have demonstrated functional cellular and humoral immune responses against the majority of HIV-1 encoded antigens in both rodents and non-human primates.

Apoptotic cell death induced by a mouse-human anti-APO-1 chimeric antibody leads to tumor regression.

The murine anti-APO-1 antibody (gamma 3, kappa) induces programmed cell death (apoptosis) following binding to the APO-1 antigen (m.w., 48 kDa) expressed, e.g., on activated or malignant lymphocytes. APO-1 expression on malignant cell lines and tissues suggested potential clinical utility supported by anti-APO-1-mediated tumor regression in a nude mouse model. A mouse-human anti-APO-1 chimeric antibody (gamma 3, kappa) with an affinity similar to that of the murine antibody was produced. Chimeric anti-APO-1 showed the same potential to inhibit growth of the SKW6.4 B-lymphoblastoid cell line as murine anti-APO-1. In addition, both the chimeric and murine anti-APO-1 antibodies were equally capable of mediating complete macroscopic tumor regression of a SKW6.4 xenotransplant in SCID mice by induction of apoptosis. Induction of apoptosis was the only mechanism for tumor regression because neither murine nor chimeric anti-APO-1 showed anti-tumor activity against solid H53 tumor (APO-1 antigen-positive, anti-APO-1-resistant) xenotransplants. Our results indicate that the chimeric anti-APO-1 antibody effectively induces apoptosis and suggest that chimeric anti-APO-1 should be evaluated for the treatment of malignant cells expressing the APO-1 antigen. However, chimeric anti-APO-I might only be used therapeutically when the antibody can be targeted specifically to tumor cells.