134 research outputs found

    Altered Neurocircuitry in the Dopamine Transporter Knockout Mouse Brain

    Get PDF
    The plasma membrane transporters for the monoamine neurotransmitters dopamine, serotonin, and norepinephrine modulate the dynamics of these monoamine neurotransmitters. Thus, activity of these transporters has significant consequences for monoamine activity throughout the brain and for a number of neurological and psychiatric disorders. Gene knockout (KO) mice that reduce or eliminate expression of each of these monoamine transporters have provided a wealth of new information about the function of these proteins at molecular, physiological and behavioral levels. In the present work we use the unique properties of magnetic resonance imaging (MRI) to probe the effects of altered dopaminergic dynamics on meso-scale neuronal circuitry and overall brain morphology, since changes at these levels of organization might help to account for some of the extensive pharmacological and behavioral differences observed in dopamine transporter (DAT) KO mice. Despite the smaller size of these animals, voxel-wise statistical comparison of high resolution structural MR images indicated little morphological change as a consequence of DAT KO. Likewise, proton magnetic resonance spectra recorded in the striatum indicated no significant changes in detectable metabolite concentrations between DAT KO and wild-type (WT) mice. In contrast, alterations in the circuitry from the prefrontal cortex to the mesocortical limbic system, an important brain component intimately tied to function of mesolimbic/mesocortical dopamine reward pathways, were revealed by manganese-enhanced MRI (MEMRI). Analysis of co-registered MEMRI images taken over the 26 hours after introduction of Mn^(2+) into the prefrontal cortex indicated that DAT KO mice have a truncated Mn^(2+) distribution within this circuitry with little accumulation beyond the thalamus or contralateral to the injection site. By contrast, WT littermates exhibit Mn^(2+) transport into more posterior midbrain nuclei and contralateral mesolimbic structures at 26 hr post-injection. Thus, DAT KO mice appear, at this level of anatomic resolution, to have preserved cortico-striatal-thalamic connectivity but diminished robustness of reward-modulating circuitry distal to the thalamus. This is in contradistinction to the state of this circuitry in serotonin transporter KO mice where we observed more robust connectivity in more posterior brain regions using methods identical to those employed here

    Ecobrick Sebagai Solusi Penanggulangan Sampah Non-Organik Rumah Tangga di Lingkungan Sayo Baru

    Get PDF
    Tujuan dari diadakannnya program kerja “Ecobrick” ini adalah untuk mengedukasi masyarakat bagaimana cara mengelola sampah di Lingkungan Sayo Baru. Permasalahan sampah (khususnya sampah anorganik) sampai saat ini menjadi masalah yang sangat krusial di masyarakat. Jika permasalahan terkait sampah di lingkungan tersebut tidak segera ditangani, maka banjir yang kerap kali terjadi di beberapa tempat di lingkungan Sayo Baru  tidak dapat teratasi, selain banjir sampah non organik yang berserakan juga mengurangi keindahan lingkungan Sayo Baru. Maka dari itu kami dari tim KKN Tematik Universitas Mataram mengajak masyarakat untuk lebih peduli lagi dalam hal bagaimana cara mengelola sampah non organik menjadi benda yang lebih bermanfaat. Dengan adanya program kerja ini, Mahasiswa KKN Tematik Universitas Mataram dapat membantu mengedukasi masyarakat tentang pentingnya mengelola sampah, mulai dari melakukan sosialisasi langsung di balai lingkungan dan pembagian brosur kepada masyarakat dan tentunya dapat mengurangi jumlah sampah harian di Lingkungan Sayo Baru, sehingga animo masyarakat untuk lebih peduli terhadap lingkungan dari sampah anorganik menjadi lebih tinggi. Adapun hasil dari kegiatan ini adalah terciptanya tempat sampah dari sampah non organik serta masyarakat sekitar merespon dengan baik karena mereka tidak bingung untuk membuang sampah rumahan yang ada

    Therapeutic DNA vaccine induces broad T cell responses in the gut and sustained protection from viral rebound and AIDS in SIV-infected rhesus macaques.

    Get PDF
    Immunotherapies that induce durable immune control of chronic HIV infection may eliminate the need for life-long dependence on drugs. We investigated a DNA vaccine formulated with a novel genetic adjuvant that stimulates immune responses in the blood and gut for the ability to improve therapy in rhesus macaques chronically infected with SIV. Using the SIV-macaque model for AIDS, we show that epidermal co-delivery of plasmids expressing SIV Gag, RT, Nef and Env, and the mucosal adjuvant, heat-labile E. coli enterotoxin (LT), during antiretroviral therapy (ART) induced a substantial 2-4-log fold reduction in mean virus burden in both the gut and blood when compared to unvaccinated controls and provided durable protection from viral rebound and disease progression after the drug was discontinued. This effect was associated with significant increases in IFN-γ T cell responses in both the blood and gut and SIV-specific CD8+ T cells with dual TNF-α and cytolytic effector functions in the blood. Importantly, a broader specificity in the T cell response seen in the gut, but not the blood, significantly correlated with a reduction in virus production in mucosal tissues and a lower virus burden in plasma. We conclude that immunizing with vaccines that induce immune responses in mucosal gut tissue could reduce residual viral reservoirs during drug therapy and improve long-term treatment of HIV infection in humans

    Envelope Determinants of Equine Lentiviral Vaccine Protection

    Get PDF
    Lentiviral envelope (Env) antigenic variation and associated immune evasion present major obstacles to vaccine development. The concept that Env is a critical determinant for vaccine efficacy is well accepted, however defined correlates of protection associated with Env variation have yet to be determined. We reported an attenuated equine infectious anemia virus (EIAV) vaccine study that directly examined the effect of lentiviral Env sequence variation on vaccine efficacy. The study identified a significant, inverse, linear correlation between vaccine efficacy and increasing divergence of the challenge virus Env gp90 protein compared to the vaccine virus gp90. The report demonstrated approximately 100% protection of immunized ponies from disease after challenge by virus with a homologous gp90 (EV0), and roughly 40% protection against challenge by virus (EV13) with a gp90 13% divergent from the vaccine strain. In the current study we examine whether the protection observed when challenging with the EV0 strain could be conferred to animals via chimeric challenge viruses between the EV0 and EV13 strains, allowing for mapping of protection to specific Env sequences. Viruses containing the EV13 proviral backbone and selected domains of the EV0 gp90 were constructed and in vitro and in vivo infectivity examined. Vaccine efficacy studies indicated that homology between the vaccine strain gp90 and the N-terminus of the challenge strain gp90 was capable of inducing immunity that resulted in significantly lower levels of post-challenge virus and significantly delayed the onset of disease. However, a homologous N-terminal region alone inserted in the EV13 backbone could not impart the 100% protection observed with the EV0 strain. Data presented here denote the complicated and potentially contradictory relationship between in vitro virulence and in vivo pathogenicity. The study highlights the importance of structural conformation for immunogens and emphasizes the need for antibody binding, not neutralizing, assays that correlate with vaccine protection. © 2013 Craigo et al

    Immunogenic Profiling in Mice of a HIV/AIDS Vaccine Candidate (MVA-B) Expressing Four HIV-1 Antigens and Potentiation by Specific Gene Deletions

    Get PDF
    BACKGROUND: The immune parameters of HIV/AIDS vaccine candidates that might be relevant in protection against HIV-1 infection are still undefined. The highly attenuated poxvirus strain MVA is one of the most promising vectors to be use as HIV-1 vaccine. We have previously described a recombinant MVA expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (referred as MVA-B), that induced HIV-1-specific immune responses in different animal models and gene signatures in human dendritic cells (DCs) with immunoregulatory function. METHODOLOGY/PRINCIPAL FINDINGS: In an effort to characterize in more detail the immunogenic profile of MVA-B and to improve its immunogenicity we have generated a new vector lacking two genes (A41L and B16R), known to counteract host immune responses by blocking the action of CC-chemokines and of interleukin 1beta, respectively (referred as MVA-B DeltaA41L/DeltaB16R). A DNA prime/MVA boost immunization protocol was used to compare the adaptive and memory HIV-1 specific immune responses induced in mice by the parental MVA-B and by the double deletion mutant MVA-B DeltaA41L/DeltaB16R. Flow cytometry analysis revealed that both vectors triggered HIV-1-specific CD4(+) and CD8(+) T cells, with the CD8(+) T-cell compartment responsible for >91.9% of the total HIV-1 responses in both immunization groups. However, MVA-B DeltaA41L/DeltaB16R enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4(+) and CD8(+) T-cell immune responses. HIV-1-specific CD4(+) T-cell responses were polyfunctional and preferentially Env-specific in both immunization groups. Significantly, while MVA-B induced preferentially Env-specific CD8(+) T-cell responses, MVA-B DeltaA41L/DeltaB16R induced more GPN-specific CD8(+) T-cell responses, with an enhanced polyfunctional pattern. Both vectors were capable of producing similar levels of antibodies against Env. CONCLUSIONS/SIGNIFICANCE: These findings revealed that MVA-B and MVA-B DeltaA41L/DeltaB16R induced in mice robust, polyfunctional and durable T-cell responses to HIV-1 antigens, but the double deletion mutant showed enhanced magnitude and quality of HIV-1 adaptive and memory responses. Our observations are relevant in the immune evaluation of MVA-B and on improvements of MVA vectors as HIV-1 vaccines

    DNA Encoding an HIV-1 Gag/Human Lysosome-Associated Membrane Protein-1 Chimera Elicits a Broad Cellular and Humoral Immune Response in Rhesus Macaques

    Get PDF
    Previous studies of HIV-1 p55Gag immunization of mice have demonstrated the usefulness of targeting antigens to the cellular compartment containing the major histocompatibility complex type II (MHC II) complex molecules by use of a DNA antigen formulation encoding Gag as a chimera with the mouse lysosome-associated membrane protein (mLAMP/gag). In the present study, we have analyzed the magnitude and breadth of Gag-specific T-lymphocyte and antibody responses elicited in Rhesus macaques after immunization with DNA encoding a human LAMP/gag (hLAMP/gag) chimera. ELISPOT analyses indicated that the average Gag-specific IFN-γ response elicited by the hLAMP/gag chimera was detectable after only two or three naked DNA immunizations in all five immunized macaques and reached an average of 1000 spot-forming cells (SFC)/10(6) PBMCs. High IFN-γ ELISPOT responses were detected in CD8(+)-depleted cells, indicating that CD4(+) T-cells play a major role in these responses. The T-cell responses of four of the macaques were also tested by use of ELISPOT to 12 overlapping 15-amino acids (aa) peptide pools containing ten peptides each, encompassing the complete Gag protein sequence. The two Mamu 08 immunized macaques responded to eight and twelve of the pools, the Mamu B01 to six, and the other macaque to five pools indicating that the hLAMP/gag DNA antigen formulation elicits a broad T-cell response against Gag. Additionally, there was a strong HIV-1-specific IgG response. The IgG antibody titers increased after each DNA injection, indicating a strong amnestic B-cell response, and were highly elevated in all the macaques after three immunizations. Moreover, the serum of each macaque recognized 13 of the 49 peptides of a 20-aa peptide library covering the complete Gag amino acid sequence. In addition, HIV-1-specific IgA antibodies were present in the plasma and external secretions, including nasal washes. These data support the findings of increased immunogenicity of genetic vaccines encoded as LAMP chimeras, including the response to DNA vaccines by non-human primates

    Immunization of mice with the nef gene from Human Immunodeficiency Virus type 1: Study of immunological memory and long-term toxicology

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The human immunodeficiency virus type 1 (HIV-1) regulatory protein, Nef, is an attractive vaccine target because it is involved in viral pathogenesis, is expressed early in the viral life cycle and harbors many T and B cell epitopes. Several clinical trials include gene-based vaccines encoding this protein. However, Nef has been shown to transform certain cell types <it>in vitro</it>. Based on these findings we performed a long-term toxicity and immunogenicity study of Nef, encoded either by Modified Vaccinia virus Ankara or by plasmid DNA. BALB/c mice were primed twice with either DNA or MVA encoding Nef and received a homologous or heterologous boost ten months later. In the meantime, the Nef-specific immune responses were monitored and at the time of sacrifice an extensive toxicological evaluation was performed, where presence of tumors and other pathological changes were assessed.</p> <p>Results</p> <p>The toxicological evaluation showed that immunization with MVAnef is safe and does not cause cellular transformation or other toxicity in somatic organs.</p> <p>Both DNAnef and MVAnef immunized animals developed potent Nef-specific cellular responses that declined to undetectable levels over time, and could readily be boosted after almost one year. This is of particular interest since it shows that plasmid DNA vaccine can also be used as a potent late booster of primed immune responses. We observed qualitative differences between the T cell responses induced by the two different vectors: DNA-encoded nef induced long-lasting CD8<sup>+ </sup>T cell memory responses, whereas MVA-encoded nef induced CD4<sup>+ </sup>T cell memory responses. In terms of the humoral immune responses, we show that two injections of MVAnef induce significant anti-Nef titers, while repeated injections of DNAnef do not. A single boost with MVAnef could enhance the antibody response following DNAnef prime to the same level as that observed in animals immunized repeatedly with MVAnef. We also demonstrate the possibility to boost HIV-1 Nef-specific immune responses using the MVAnef construct despite the presence of potent anti-vector immunity.</p> <p>Conclusion</p> <p>This study shows that the nef gene vectored by MVA does not induce malignancies or other adverse effects in mice. Further, we show that when the nef gene is delivered by plasmid or by a viral vector, it elicits potent and long-lasting immune responses and that these responses can be directed towards a CD4<sup>+ </sup>or a CD8<sup>+ </sup>T cell response depending on the choice of vector.</p

    Phase 1 Safety and Immunogenicity Evaluation of ADVAX, a Multigenic, DNA-Based Clade C/B' HIV-1 Candidate Vaccine

    Get PDF
    BACKGROUND: We conducted a Phase I dose escalation trial of ADVAX, a DNA-based candidate HIV-1 vaccine expressing Clade C/B' env, gag, pol, nef, and tat genes. Sequences were derived from a prevalent circulating recombinant form in Yunnan, China, an area of high HIV-1 incidence. The objective was to evaluate the safety and immunogenicity of ADVAX in human volunteers. METHODOLOGY/PRINCIPAL FINDINGS: ADVAX or placebo was administered intramuscularly at months 0, 1 and 3 to 45 healthy volunteers not at high risk for HIV-1. Three dosage levels [0.2 mg (low), 1.0 mg (mid), and 4.0 mg (high)] were tested. Twelve volunteers in each dosage group were assigned to receive ADVAX and three to receive placebo in a double-blind design. Subjects were followed for local and systemic reactogenicity, adverse events, and clinical laboratory parameters. Study follow up was 18 months. Humoral immunogenicity was evaluated by anti-gp120 binding ELISA. Cellular immunogenicity was assessed by a validated IFNgamma ELISpot assay and intracellular cytokine staining. ADVAX was safe and well-tolerated, with no vaccine-related serious adverse events. Local and systemic reactogenicity events were reported by 64% and 42% of vaccine recipients, respectively. The majority of events were mild. The IFNgamma ELISpot response rates to any HIV antigen were 0/9 (0%) in the placebo group, 3/12 (25%) in the low-dosage group, 4/12 (33%) in the mid-dosage group, and 2/12 (17%) in the high-dosage group. Overall, responses were generally transient and occurred to each gene product, although volunteers responded to single antigens only. Binding antibodies to gp120 were not detected in any volunteers, and HIV seroconversion did not occur. CONCLUSIONS/SIGNIFICANCE: ADVAX delivered intramuscularly is safe, well-tolerated, and elicits modest but transient cellular immune responses. TRIAL REGISTRATION: Clinicaltrials.gov NCT00249106.published_or_final_versio
    corecore