An assessment of donor-to-recipient transmission patterns of human cytomegalovirus by analysis of viral genomic variants.

BACKGROUND: We studied human cytomegalovirus (CMV) donor-to-recipient transmission patterns in organ transplantation by analyzing genomic variants on the basis of CMV glycoprotein B (gB) genotyping. METHODS: Organ transplant recipients were included in the study if they had CMV viremia, if they had received an organ from a CMV-seropositive donor, and if there was at least 1 other recipient of an organ from the same donor who developed CMV viremia. Genotypes (gB1-4) were determined by real-time polymerase chain reaction. RESULTS: Forty-seven recipients of organs from 21 donors developed CMV viremia. Twenty-three recipients had a pretransplant donor/recipient (D/R) CMV serostatus of D(+)/R(+), and 24 had a serostatus of D(+)/R(-). The prevalences of genotypes in recipients were as follows: for gB1, 51% (n = 24); for gB2, 19% (n = 9); for gB3, 9% (n = 4); for gB4, 0% (n = 0); and for mixed infection, 21% (n = 10). Recipients of an organ from a common donor had infection with CMV of the same gB genotype in 12 (57%) of 21 instances. Concordance between genotypes was higher among seronegative (i.e., D(+)/R(-)) recipients than among seropositive (D(+)/R(+)) recipients, although discordances resulting from the transmission of multiple strains were seen. In seropositive recipients, transmission of multiple strains from the donor could not be differentiated from reactivation of a recipient's own strains. CONCLUSION: Our analysis of strain concordance among recipients of organs from common donors showed that transmission of CMV has complex dynamic patterns. In seropositive recipients, transmission or reactivation of multiple CMV strains is possible.

Granular layer in the periplasmic space of gram-positive bacteria and fine structures of Enterococcus gallinarum and Streptococcus gordonii septa revealed by cryo-electron microscopy of vitreous sections.

High-resolution structural information on optimally preserved bacterial cells can be obtained with cryo-electron microscopy of vitreous sections. With the help of this technique, the existence of a periplasmic space between the plasma membrane and the thick peptidoglycan layer of the gram-positive bacteria Bacillus subtilis and Staphylococcus aureus was recently shown. This raises questions about the mode of polymerization of peptidoglycan. In the present study, we report the structure of the cell envelope of three gram-positive bacteria (B. subtilis, Streptococcus gordonii, and Enterococcus gallinarum). In the three cases, a previously undescribed granular layer adjacent to the plasma membrane is found in the periplasmic space. In order to better understand how nascent peptidoglycan is incorporated into the mature peptidoglycan, we investigated cellular regions known to represent the sites of cell wall production. Each of these sites possesses a specific structure. We propose a hypothetic model of peptidoglycan polymerization that accommodates these differences: peptidoglycan precursors could be exported from the cytoplasm to the periplasmic space, where they could diffuse until they would interact with the interface between the granular layer and the thick peptidoglycan layer. They could then polymerize with mature peptidoglycan. We report cytoplasmic structures at the E. gallinarum septum that could be interpreted as cytoskeletal elements driving cell division (FtsZ ring). Although immunoelectron microscopy and fluorescence microscopy studies have demonstrated the septal and cytoplasmic localization of FtsZ, direct visualization of in situ FtsZ filaments has not been obtained in any electron microscopy study of fixed and dehydrated bacteria.

Hypomorphic mutation in the site-1 protease Mbtps1 endows resistance to persistent viral infection in a cell-specific manner.

The prototypic arenavirus lymphocytic choriomeningitis virus (LCMV), which naturally persists in rodents, represents a model for HIV, HBV, and HCV. Cleavage of the viral glycoprotein precursor by membrane-bound transcription factor peptidase, site 1 (Mbtps1 or site-1 protease), is crucial for the life cycle of arenaviruses and therefore represents a potential target for therapy. Recently, we reported a viable hypomorphic allele of Mbtps1 (woodrat) encoding a protease with diminished enzymatic activity. Using the woodrat allele, we examine the role of Mbtps1 during persistent LCMV infection. Surprisingly, Mbtps1 inhibition limits persistent but not acute viral infection and is associated with an organ/cell type-specific decrease in viral titers. Analysis of bone marrow-derived dendritic cells from woodrat mice supports their specific role in resolving persistent viral infection. These results support in vivo targeting of Mbtps1 in the treatment of arenavirus infections and demonstrate a critical role for dendritic cells in persistent viral infections.

Marked increase in the secretion of a fully antigenic recombinant carcinoembryonic antigen obtained by deletion of its hydrophobic tail.

Carcinoembryonic antigen (CEA) is a well-known tumor marker, consisting of a single heavily glycosylated polypeptide chain (mol. wt 200 kD), bound to the cell surface by a phosphatidylinositol-glycan anchor. The hydrophobic domain, encoded by the 3' end of the open reading frame of the CEA gene is not present in the mature protein. This domain is assumed to play an important role in the targeting and attachment of CEA to the cell surface. To verify this hypothesis, a recombinant CEA cDNA lacking the 78 b.p. of the 3' region, encoding the 26 a.a. hydrophobic domain, was prepared in a Rc/CMV expression vector containing a neomycin resistance gene. The construct was transfected by the calcium phosphate technique into CEA-negative human and rat colon carcinoma cell lines. Geneticin-resistant transfectants were screened for the presence of CEA in the supernatant and positive clones were isolated. As determined by ELISA, up to 13 micrograms of recombinant CEA per 10(6) cells was secreted within 72 hr by the human transfected cells and about 1 microgram by the rat cells. For comparison, two human carcinoma cell lines, CO112 and LS174T, selected for high CEA expression, shed about 45 and 128 ng per 10(6) cells within 72 hr, respectively. Western blot analysis showed that the size of the recombinant CEA secreted by the transfected human cells is identical to that of reference CEA purified from human colon carcinomas metastases (about 200 kD). The recombinant CEA synthesized by the transfected rat carcinoma cells has a smaller size (about 144 kD, possibly due to incomplete glycosylation), as has already been observed for CEA produced by rat colon carcinoma cells transfected with full-length CEA cDNA. The 100-fold increase in secretion of rCEA encoded by truncated CEA cDNA transfected in human cells confirms the essential role of this domain in the targeting and anchoring of the glycoprotein. These results suggest a new approach for the in vitro production of large amounts of CEA needed in research laboratories and for immunoassay kits.

MsrR contributes to cell surface characteristics and virulence in Staphylococcus aureus.

MsrR, a factor contributing to methicillin resistance in Staphylococcus aureus, belongs to the LytR-CpsA-Psr family of cell envelope-associated proteins. Deletion of msrR increased cell size and aggregation, and altered envelope properties, leading to a temporary reduction in cell surface hydrophobicity, diminished colony-spreading ability, and an increased susceptibility to Congo red. The reduced phosphorus content of purified cell walls of the msrR mutant suggested a reduction in wall teichoic acids, which may explain some of the observed phenotypes. Microarray analysis of the msrR deletion mutant revealed only minor changes in the global transcriptome, suggesting that MsrR has structural rather than regulatory functions. Importantly, virulence of the msrR mutant was decreased in a nematode-killing assay as well as in rat experimental endocarditis. MsrR is therefore likely to play a role in cell envelope maintenance, cell separation, and pathogenicity of S. aureus.

MOBP-specific cellular immune responses are weaker than MOG-specific cellular immune responses in patients with multiple sclerosis and healthy subjects.

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). Myelin oligodendrocyte glycoprotein (MOG) and myelin oligodendrocyte basic protein (MOBP) were both shown to be highly encephalitogenic in animal models of MS. In contrast, the association of MOG- and MOBP-specific humoral or cellular immune responses and MS in humans is far less established. In this study, we sought to analyse MOG- and MOBP-specific T-cell responses in a large cohort of patients with various stages of the disease. Patients with other neurological diseases and healthy subjects were enrolled to serve as control study subjects. We determined the proliferation and the secretion of IFN-γ secretion in our cohort. We found that MOG-specific T-cell responses were higher and more frequent as compared to MOBP-specific ones. However, both MS patients and control study subjects had similar myelin-specific T-cell responses at the periphery, thus calling for more precise studies at CNS level.

Lentiviral Vector Tropism In Degenerating Retinas

Introduction: In normal mice, lentiviral vector (LV) shows a great efficiency to infect the RPE cells, but transduces retinal neurons more efficiently during development. Here, we investigated the tropism of LV in the degenerating retina of mice, knowing that the retina structure changes during degeneration. We postulated that the viral transduction would be increased by the alteration of the interphotoreceptor matrix (IPM). We tested two different LV-pseudotypes using the VSVG and the Mokola envelopes. Methods: Subretinal injections were performed in wild-type (C57/Bl6) and rhodopsin knockout (Rho-/-) mice. We injected LV-VSVG-EFS-GFPII into 3.3-4.9 month old mice and LV-VSVG-Rho-GFP into 1-1.4 month old mice to target the photoreceptors (PR). LV-MOK-CMV-GFP was injected into 2.4-3.3 months old mice. We sacrificed the animals one week post injection, used immunohistochemistry to identify the transduced cells, and investigated the OLM integrity. Results: Using LV-VSVG-EFS-GFPII into 3.3-4.9 months mice, we observed significant retinal and RPE transduction in Rho-/- mice. However, the retinas showed transduction mainly at the injection's site. We mostly observed GFP+ cells having a Müller cell morphology. Using LV-MOK-CMV-GFP into 2.4-3.3 months mice, we evidenced the same pattern of viral infection, but with more Müller cells targeted by the virus. Using LV-VSVG-Rho-GFP into 1-1.4 month old mice, we don't note any difference between Rho-/- and wild-type mice for transduced cells. The IPM stained with ZO1 appears irregular into the 4.9 months old Rho-/- mice; for the youngest mice (Rho-/- and C57/Bl6), there is no modification of the IPM. Conclusion: The degeneration improves retinal cells transduction due to the alteration of the IPM in old Rho-/- mice. Müller cells seem (by morphological evidences) to be the principal cells expressing the transgene. The LV with Mokola envelope can transduce Müller cells in a degenerating retina with an intact IPM. In 1 month old mice, the degeneration doesn't enhance the transduction in rod PR probably because the IPM is not yet altered. The possibility to target photoreceptors at a later stage of the degeneration is under investigation.

Loco-regional administration of anticancer agents : isolated lung perfusion with doxorubicin hypoxic abdominal stop-flow perfusion with gemcitabine

SUMMARY Regional drug delivery is an approach designed to improve the selectivity of anticancer chemotherapy. The advantage of regional treatments lies in increasing the drug concentration in the affected organ, while the rest of the organism is spared, thus improving efficacy and limiting treatment toxicity. The goal of this thesis was to assess the distribution throughout the body and the disposition (pharmacokinetics) of two anticancer agents, doxorubicin and gemcitabine, administered by two different regional administration modalities: isolated lung perfusion (ILP) for pulmonary metastases from soft tissue sarcomas and abdominal stop-flow hypoxic perfusion for advanced pancreatic cancers, respectively. For this purpose, two high-performance liquid chromatography methods were developed and validated. The first enabled the determination of doxorubicin in four different biological matrices: serum, reconstituted effluent, tissues with low levels of doxorubicin and tissues with high levels of doxorubicin. The second allows the analysis of gemcitabine and its principal metabolite dFdU in plasma. The administration of doxorubicin by ILP was studied in three preclinical studies (one on pigs and two on rats). It was first shown that, regardless of the administration mode, doxorubicin was not homogeneously distributed throughout the lung and that some regions remained out of reach. Secondly, it was demonstrated that doxorubicin did not adequately reach the tumours despite very high levels found in the lung. Finally, an attempt to enhance the doxorubicin tumoural uptake by pharmacologic modulation using two P-glycoprotein inhibitors, cyclosporin and valspodar, was unsuccessful. The last part of this work involves the administration of gemcitabine by abdominal stop-flow as a part of a phase I clinical trial in patients with advanced pancreatic disease or resistant malignant ascites. The study has demonstrated that the regional exposure to gemcitabine was increased while the exposure of the entire organism was similar to standard intravenous administrations. From a toxicological perspective, the procedure was rather well tolerated. However, even if no clinical response is expected from a phase I study, no hints of clinical responses were unfortunately observed. In conclusion, even if loco-regional therapies may afford the pharmacological advantage of increasing anticancer drug levels at the tumour site, further studies of these investigational treatment modalities are warranted to ascertain whether they can provide a significant improvement of the cancer therapy for patients, in terms of treatment tolerability, improved responses and survival rates. RÉSUMÉ L'administration locorégionale d'agents anticancéreux est une approche destinée à augmenter la sélectivité du traitement. L'avantage des traitements régionaux repose sur le fait que la concentration du médicament cytostatique est augmentée dans l'organe où est localisée la tumeur, alors que le reste de l'organisme est épargné, améliorant ainsi en théorie l'efficacité du traitement et en limitant sa toxicité. Le but de ce travail de thèse avait pour objectif de préciser, la pharmacocinétique au sein de l'organisme de deux agents anticancéreux, la doxorubicine et la gemcitabine, administrés par deux types de perfusions loco-régionales: la perfusion isolée du poumon (ILP) pour les métastases pulmonaires de sarcomes des tissus mous, et la perfusion hypoxique (stop-flow) abdominale pour les cancers avancés du pancréas. Dans cette optique, deux méthodes de chromatographie liquide à haute performance ont été développées et validées. La première permet le dosage de la doxorubicine dans quatre milieux biologiques: le sérum, l'effluent reconstitué, ainsi que des tissus contenant des concentrations faibles et élevées en doxorubicine. La seconde méthode permet le dosage dans le plasma de la gemcitabine et de son principal métabolite, le dFdU. L'administration de doxorubicine par ILP a été étudiée dans trois études précliniques (une chez le porc et deux chez le rat). Il a été montré, dans un premier temps, que la doxorubicine n'était pas distribuée de façon homogène au sein du poumon, quel que soit son mode d'administration. Dans un deuxième temps, il a été démontré que le médicament n'atteignait pas les tumeurs de façon adéquate, malgré des concentrations très élevées au sein du tissu pulmonaire. Finalement, une tentative d'augmenter la pénétration tumorale de la doxorubicine par une modulation pharmacologique de la P-glycoprotéine en utilisant la cyclosporine et le valspodar n'a pas abouti. La dernière partie de ce travail concernait l'administration de gemcitabine par stop-flow abdominal dans le cadre d'une étude clinique de phase I menée auprès de patients atteints de cancers avancés du pancréas ou d'ascites malignes réfractaires. Cette étude a démontré que l'exposition régionale à la gemcitabine était augmentée, alors que l'exposition de l'organisme était similaire à une administration de dose standard par voie intraveineuse. D'un point de vue toxicologique la procédure fut relativement bien tolérée. Cependant, même s'il n'est pas attendu de réponses cliniques dans une étude de phase I, aucun signe de réponse au traitement n'a pu être malheureusement observé. En conclusion, même si les thérapies loco-régionales présentent -en théorie- l'avantage pharmacologique d'augmenter les taux du médicaments anticancéreux sur le site de la tumeur, d'autres études précliniques et cliniques sont nécessaires pour démontrer que ces nouvelles modalités de traitement, de nature investigationelle à présent, apportent une réelle amélioration pour la prise en charge des patients cancéreux, en terme de tolérance au traitement et de l'augmentation des taux de réponses et de survie.

Off-axis low coherence interferometry contouring

In this article we present a method to achieve tri-dimensional contouring of macroscopic objects. A modified reference wave speckle interferometer is used in conjunction with a source of reduced coherence. The depth signal is given by the envelope of the interference signal, directly determined by the coherence length of the source. Fringes are detected in the interferogram obtained by a single shot and are detected by means of adequate filtering. With the approach based on off-axis configuration, a contour line can be extracted from a single acquisition, thus allowing to use the system in harsh environment. (C) 2009 Elsevier B.V. All rights reserved.

Differentiation of postmitotic neuroblasts into substance P-immunoreactive sensory neurons in dissociated cultures of chick dorsal root ganglion.

Counts performed on dissociated cell cultures of E10 chick embryo dorsal root ganglia (DRG) showed after 4-6 days of culture a pronounced decline of the neuronal population in neuron-enriched cultures and a net gain in the number of ganglion cells in mixed DRG cell cultures (containing both neurons and nonneuronal cells). In the latter case, the increase in the number of neurons was found to depend on NGF and to average 119% in defined medium or 129% in horse serum-supplemented medium after 6 days of culture. The lack of [3H]thymidine incorporation into the neuronal population indicated that the newly formed ganglion cells were not generated by proliferation. On the contrary, the differentiation of postmitotic neuroblasts present in the nonneuronal cell compartment was supported by sequential microphotographs of selected fields taken every hour for 48-55 hr after 3 days of culture. Apparently nonneuronal flat dark cells exhibited morphological changes and gradually evolved into neuronal ovoid and refringent cell bodies with expanding neurites. The ultrastructural organization of these evolving cells corresponded to that of primitive or intermediate neuroblasts. The neuronal nature of these rounding up cell bodies was indeed confirmed by the progressive expression of various neuronal cell markers (150 and 200-kDa neurofilament triplets, neuron specific enolase, and D2/N-CAM). Besides a constant lack of immunoreactivity for tyrosine hydroxylase, somatostatin, parvalbumin, and calbindin-D 28K and a lack of cytoenzymatic activity for carbonic anhydrase, all the newly produced neurons expressed three main phenotypic characteristics: a small cell body, a strong immunoreactivity to MAG, and substance P. Hence, ganglion cells newly differentiated in culture would meet characteristics ascribed to small B sensory neurons and more specifically to a subpopulation of ganglion cells containing substance P-immunoreactive material.

A new factor stimulating peptidoglycan hydrolysis to separate daughter cells in Caulobacter crescentus.

Cell division in Gram-negative bacteria involves the co-ordinated invagination of the three cell envelope layers to form two new daughter cell poles. This complex process starts with the polymerization of the tubulin-like protein FtsZ into a Z-ring at mid-cell, which drives cytokinesis and recruits numerous other proteins to the division site. These proteins are involved in Z-ring constriction, inner- and outer-membrane invagination, peptidoglycan remodelling and daughter cell separation. Three papers in this issue of Molecular Microbiology, from the teams of Lucy Shapiro, Martin Thanbichler and Christine Jacobs-Wagner, describe a novel protein, called DipM for Division Involved Protein with LysM domains, that is required for cell division in Caulobacter crescentus. DipM localizes to the mid-cell during cell division, where it is necessary for the hydrolysis of the septal peptidoglycan to remodel the cell wall. Loss of DipM results in severe defects in cell envelope constriction, which is deleterious under fast-growth conditions. State-of-the-art microscopy experiments reveal that the peptidoglycan is thicker and that the cell wall is incorrectly organized in DipM-depleted cells compared with wild-type cells, demonstrating that DipM is essential for reorganizing the cell wall at the division site, for envelope invagination and cell separation in Caulobacter.

Immune responses to JC virus in patients with multiple sclerosis treated with natalizumab: a cross-sectional and longitudinal study.

BACKGROUND: Natalizumab is used to prevent relapses and progression of disability in patients with multiple sclerosis but has been associated with progressive multifocal leukoencephalopathy (PML). We aimed to better understand the associations between JC virus, which causes PML, and natalizumab treatment. METHODS: We prospectively assessed patients with multiple sclerosis who started treatment with natalizumab. Blood and urine samples were tested for the presence of JC virus DNA with quantitative real-time PCR before treatment and at regular intervals after treatment onset for up to 18 months. At the same timepoints, by use of proliferation and enzyme-linked immunospot assays, the cellular immune responses against JC virus, Epstein-Barr virus, cytomegalovirus, myelin oligodendrocyte glycoprotein, and myelin oligodendrocyte basic protein (MOBP) were assessed. Humoral immune response specific to JC virus was assessed with an enzyme immunoassay. The same experiments were done on blood samples from patients with multiple sclerosis before and 10 months after the start of interferon beta treatment. FINDINGS: We assessed 24 patients with multiple sclerosis who received natalizumab and 16 who received interferon beta. In patients treated with natalizumab, JC virus DNA was not detected in the blood at any timepoint. However, JC virus DNA was present in the urine of six patients and in most of these patients the concentrations of JC virus DNA were stable over time. Compared with pretreatment values, the cellular immune response was increased to cytomegalovirus at 6 months, to JC virus at 1, 9, and 12 months, and to Epstein-Barr virus and MOBP at 12 months. Humoral responses remained stable. There were no increases in cellular immune responses specific to the viruses or myelin proteins in the 16 patients treated with interferon beta. INTERPRETATION: Natalizumab increases cellular immune responses specific to viruses and myelin proteins in the peripheral blood after 1 year, without evidence of viral reactivation. FUNDING: Swiss National Foundation, Swiss Society for Multiple Sclerosis, and Biogen Dompé.

CYP3A5 and ABCB1 genes and hypertension.

Hypertension is the first single modifiable cause of disease burden worldwide. Genes encoding proteins that are involved in the metabolism (CYP3A5) and transport (ABCB1) of drugs and hormones might contribute to blood pressure control in humans. Indeed, recent data have suggested that CYP3A5 and ABCB1 gene polymorphisms are associated with blood pressure in the rat as well as in humans. Interestingly, the effects of these genes on blood pressure appear to be modified by dietary salt intake. This review summarizes what is known regarding the relationships of the ABCB1 and CYP3A5 genes with blood pressure, and discusses the potential underlying mechanisms of the association. If the role of these genes in blood pressure control is confirmed in other populations and other ethnic groups, these findings would point toward a new pathway for blood pressure control in humans.

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The pharmacokinetic profile of imatinib has been assessed in healthy subjects and in population studies among thousands of patients with CML or GIST. Imatinib is rapidly and extensively absorbed from the GI tract, reaching a peak plasma concentration (Cmax) within 1-4 h following administration. Imatinib bioavailability is high (98%) and independent of food intake. Imatinib undergoes rapid and extensive distribution into tissues, with minimal penetration into the central nervous system. In the circulation, it is approximately 95% bound to plasma proteins, principally α1-acid glycoprotein (AGP) and albumin. Imatinib undergoes metabolism in the liver via the cytochrome P450 enzyme system (CYP), with CYP3A4 being the main isoenzyme involved. The N-desmethyl metabolite CGP74588 is the major circulating active metabolite. The typical elimination half-life for imatinib is approximately 14-22 h. Imatinib is characterized by large inter-individual pharmacokinetic variability, which reflects in a wide spread of concentrations observed under standard dosage. Besides adherence, several factors have been shown to influence this variability, especially demographic characteristics (sex, age, body weight and disease diagnosis), blood count characteristics, enzyme activity (mainly CYP3A4), drug interactions, activity of efflux transporters and plasma levels of AGP. Additionally, recent retrospective studies have shown that drug exposure, reflected in either the area under the concentration-time curve (AUC) or more conveniently the trough level (Cmin), correlates with treatment outcomes. Increased toxicity has been associated with high plasma levels, and impaired clinical efficacy with low plasma levels. While no upper concentration limit has been formally established, a lower limit for imatinib Cmin of about 1000 ng/mL has been proposed repeatedly for improving outcomes in CML and GIST patients. Imatinib is licensed for use in chronic phase CML and GIST at a fixed dose of 400 mg once daily (600 mg in some other indications) despite substantial pharmacokinetic variability caused by both genetic and acquired factors. The dose can be modified on an individual basis in cases of insufficient response or substantial toxic effects. Imatinib would, however, meet traditional criteria for a therapeutic drug monitoring (TDM) program: long-term therapy, measurability, high inter-individual but restricted intra-individual variability, limited pharmacokinetic predictability, effect of drug interactions, consistent association between concentration and response, suggested therapeutic threshold, reversibility of effect and absence of early markers of efficacy and toxic effects. Large-scale, evidence-based assessments of drug concentration monitoring are therefore still warranted for the personalization of imatinib treatment.

Dendritic cell-specific antigen delivery by coronavirus vaccine vectors induces long-lasting protective antiviral and antitumor immunity.

Efficient vaccination against infectious agents and tumors depends on specific antigen targeting to dendritic cells (DCs). We report here that biosafe coronavirus-based vaccine vectors facilitate delivery of multiple antigens and immunostimulatory cytokines to professional antigen-presenting cells in vitro and in vivo. Vaccine vectors based on heavily attenuated murine coronavirus genomes were generated to express epitopes from the lymphocytic choriomeningitis virus glycoprotein, or human Melan-A, in combination with the immunostimulatory cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). These vectors selectively targeted DCs in vitro and in vivo resulting in vector-mediated antigen expression and efficient maturation of DCs. Single application of only low vector doses elicited strong and long-lasting cytotoxic T-cell responses, providing protective antiviral and antitumor immunity. Furthermore, human DCs transduced with Melan-A-recombinant human coronavirus 229E efficiently activated tumor-specific CD8(+) T cells. Taken together, this novel vaccine platform is well suited to deliver antigens and immunostimulatory cytokines to DCs and to initiate and maintain protective immunity.