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Sample records for hiv-1 poxvirus immunizations

  1. HIV/AIDS Vaccine Candidates Based on Replication-Competent Recombinant Poxvirus NYVAC-C-KC Expressing Trimeric gp140 and Gag-Derived Virus-Like Particles or Lacking the Viral Molecule B19 That Inhibits Type I Interferon Activate Relevant HIV-1-Specific B and T Cell Immune Functions in Nonhuman Primates.

    PubMed

    García-Arriaza, Juan; Perdiguero, Beatriz; Heeney, Jonathan L; Seaman, Michael S; Montefiori, David C; Yates, Nicole L; Tomaras, Georgia D; Ferrari, Guido; Foulds, Kathryn E; Roederer, Mario; Self, Steven G; Borate, Bhavesh; Gottardo, Raphael; Phogat, Sanjay; Tartaglia, Jim; Barnett, Susan W; Burke, Brian; Cristillo, Anthony D; Weiss, Deborah E; Lee, Carter; Kibler, Karen V; Jacobs, Bertram L; Wagner, Ralf; Ding, Song; Pantaleo, Giuseppe; Esteban, Mariano

    2017-05-01

    The nonreplicating attenuated poxvirus vector NYVAC expressing clade C(CN54) HIV-1 Env(gp120) and Gag-Pol-Nef antigens (NYVAC-C) showed limited immunogenicity in phase I clinical trials. To enhance the capacity of the NYVAC vector to trigger broad humoral responses and a more balanced activation of CD4(+) and CD8(+) T cells, here we compared the HIV-1-specific immunogenicity elicited in nonhuman primates immunized with two replicating NYVAC vectors that have been modified by the insertion of the K1L and C7L vaccinia virus host range genes and express the clade C(ZM96) trimeric HIV-1 gp140 protein or a Gag(ZM96)-Pol-Nef(CN54) polyprotein as Gag-derived virus-like particles (termed NYVAC-C-KC). Additionally, one NYVAC-C-KC vector was generated by deleting the viral gene B19R, an inhibitor of the type I interferon response (NYVAC-C-KC-ΔB19R). An immunization protocol mimicking that of the RV144 phase III clinical trial was used. Two groups of macaques received two doses of the corresponding NYVAC-C-KC vectors (weeks 0 and 4) and booster doses with NYVAC-C-KC vectors plus the clade C HIV-1 gp120 protein (weeks 12 and 24). The two replicating NYVAC-C-KC vectors induced enhanced and similar HIV-1-specific CD4(+) and CD8(+) T cell responses, similar levels of binding IgG antibodies, low levels of IgA antibodies, and high levels of antibody-dependent cellular cytotoxicity responses and HIV-1-neutralizing antibodies. Small differences within the NYVAC-C-KC-ΔB19R group were seen in the magnitude of CD4(+) and CD8(+) T cells, the induction of some cytokines, and the neutralization of some HIV-1 isolates. Thus, replication-competent NYVAC-C-KC vectors acquired relevant immunological properties as vaccine candidates against HIV/AIDS, and the viral B19 molecule exerts some control of immune functions.IMPORTANCE It is of special importance to find a safe and effective HIV/AIDS vaccine that can induce strong and broad T cell and humoral immune responses correlating with HIV-1

  2. Modulation of HIV-1 immunity by adjuvants

    PubMed Central

    Moody, M. Anthony

    2014-01-01

    Purpose of review To summarize the role of adjuvants in eliciting desirable antibody responses against HIV-1 with particular emphasis on both historical context and recent developments. Recent findings Increased understanding of the role of pattern recognition receptors such as Toll-like receptors in recruiting and directing the immune system has increased the variety of adjuvant formulations being tested in animal models and humans. Across all vaccine platforms, adjuvant formulations have been shown to enhance desirable immune responses such as higher antibody titers and increased functional activity. Although no vaccine formulation has yet succeeded in eliciting broad neutralizing antibodies against HIV-1, the ability of adjuvants to direct the immune response to immunogens suggests they will be critically important in any successful HIV-1 vaccine. Summary The parallel development of adjuvants along with better HIV-1 immunogens will be needed for a successful AIDS vaccine. Additional comparative testing will be required to determine the optimal adjuvant and immunogen regimen that can elicit antibody responses capable of blocking HIV-1 transmission. PMID:24670321

  3. A comparative analysis of HIV-specific mucosal/systemic T cell immunity and avidity following rDNA/rFPV and poxvirus-poxvirus prime boost immunisations.

    PubMed

    Ranasinghe, Charani; Eyers, Fiona; Stambas, John; Boyle, David B; Ramshaw, Ian A; Ramsay, Alistair J

    2011-04-05

    In this study we have firstly compared a range of recombinant DNA poxvirus prime-boost immunisation strategies and shown that combined intramuscular (i.m.) 2× DNA-HIV/intranasal (i.n.) 2× FPV-HIV prime-boost immunisation can generate high-level of HIV-specific systemic (spleen) and mucosal (genito-rectal nodes, vaginal tissues and lung tissues) T cell responses and HIV-1 p24 Gag-specific serum IgG1, IgG2a and mucosal IgG, SIgA responses in vaginal secretions in BALB/c mice. Data indicate that following rDNA priming, two rFPV booster immunisations were necessary to generate good antibody and mucosal T cell immunity. This data also revealed that mucosal uptake of recombinant fowl pox (rFPV) was far superior to plasmid DNA. To further evaluate CD8+ T cell immunity, i.m. 2× DNA-HIV/i.n. 1× FPV-HIV immunisation strategy was directly compared with single shot poxvirus/poxvirus, i.n. FPV-HIV/i.m. VV-HIV immunisation. Results indicate that the latter strategy was able to generate strong sustained HIV-specific CD8+ T cells with higher avidity, broader cytokine/chemokine profiles and better protection following influenza-K(d)Gag(197-205) challenge compared to rDNA poxvirus prime-boost strategy. Our findings further substantiate the importance of vector selection/combination, order and route of delivery when designing effective vaccines for HIV-1.

  4. Head-to-Head Comparison of Poxvirus NYVAC and ALVAC Vectors Expressing Identical HIV-1 Clade C Immunogens in Prime-Boost Combination with Env Protein in Nonhuman Primates

    PubMed Central

    García-Arriaza, Juan; Perdiguero, Beatriz; Heeney, Jonathan; Seaman, Michael; Montefiori, David C.; Labranche, Celia; Yates, Nicole L.; Shen, Xiaoying; Tomaras, Georgia D.; Ferrari, Guido; Foulds, Kathryn E.; McDermott, Adrian; Kao, Shing-Fen; Roederer, Mario; Hawkins, Natalie; Self, Steve; Yao, Jiansheng; Farrell, Patrick; Phogat, Sanjay; Tartaglia, Jim; Barnett, Susan W.; Burke, Brian; Cristillo, Anthony; Weiss, Deborah; Lee, Carter; Kibler, Karen; Jacobs, Bert; Asbach, Benedikt; Wagner, Ralf; Ding, Song; Pantaleo, Giuseppe

    2015-01-01

    ABSTRACT We compared the HIV-1-specific cellular and humoral immune responses elicited in rhesus macaques immunized with two poxvirus vectors (NYVAC and ALVAC) expressing the same HIV-1 antigens from clade C, Env gp140 as a trimeric cell-released protein and a Gag-Pol-Nef polyprotein as Gag-induced virus-like particles (VLPs) (referred to as NYVAC-C and ALVAC-C). The immunization protocol consisted of two doses of the corresponding poxvirus vector plus two doses of a combination of the poxvirus vector and a purified HIV-1 gp120 protein from clade C. This immunogenicity profile was also compared to that elicited by vaccine regimens consisting of two doses of the ALVAC vector expressing HIV-1 antigens from clades B/E (ALVAC-vCP1521) plus two doses of a combination of ALVAC-vCP1521 and HIV-1 gp120 protein from clades B/E (similar to the RV144 trial regimen) or clade C. The results showed that immunization of macaques with NYVAC-C stimulated at different times more potent HIV-1-specific CD4+ T-cell responses and induced a trend toward higher-magnitude HIV-1-specific CD8+ T-cell immune responses than did ALVAC-C. Furthermore, NYVAC-C induced a trend toward higher levels of binding IgG antibodies against clade C HIV-1 gp140, gp120, or murine leukemia virus (MuLV) gp70-scaffolded V1/V2 and toward best cross-clade-binding IgG responses against HIV-1 gp140 from clades A, B, and group M consensus, than did ALVAC-C. Of the linear binding IgG responses, most were directed against the V3 loop in all immunization groups. Additionally, NYVAC-C and ALVAC-C also induced similar levels of HIV-1-neutralizing antibodies and antibody-dependent cellular cytotoxicity (ADCC) responses. Interestingly, binding IgA antibody levels against HIV-1 gp120 or MuLV gp70-scaffolded V1/V2 were absent or very low in all immunization groups. Overall, these results provide a comprehensive survey of the immunogenicity of NYVAC versus ALVAC expressing HIV-1 antigens in nonhuman primates and indicate that

  5. HIV-1 Strategies of Immune Evasion

    NASA Astrophysics Data System (ADS)

    Castiglione, F.; Bernaschi, M.

    We simulate the progression of the HIV-1 infection in untreated host organisms. The phenotype features of the virus are represented by the replication rate, the probability of activating the transcription, the mutation rate and the capacity to stimulate an immune response (the so-called immunogenicity). It is very difficult to study in-vivo or in-vitro how these characteristics of the virus influence the evolution of the disease. Therefore we resorted to simulations based on a computer model validated in previous studies. We observe, by means of computer experiments, that the virus continuously evolves under the selective pressure of an immune response whose effectiveness downgrades along with the disease progression. The results of the simulations show that immunogenicity is the most important factor in determining the rate of disease progression but, by itself, it is not sufficient to drive the disease to a conclusion in all cases.

  6. Innate immune sensing of HIV-1 by dendritic cells.

    PubMed

    Luban, Jeremy

    2012-10-18

    HIV-1-specific antibodies and CD8(+) cytotoxic T cells are detected in most HIV-1-infected people, yet HIV-1 infection is not eradicated. Contributing to the failure to mount a sterilizing immune response may be the inability of antigen-presenting dendritic cells (DCs) to sense HIV-1 during acute infection, and thus the inability to effectively prime naive, HIV-1-specific T cells. Recent findings related to DC-expressed innate immune factors including SAMHD1, TREX1, and TRIM5 provide a molecular basis for understanding why DCs fail to adequately sense invasion by this deadly pathogen and suggest experimental approaches to improve T cell priming to HIV-1 in prophylactic vaccination protocols. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Immune reconstitution and vaccination outcome in HIV-1 infected children

    PubMed Central

    Cagigi, Alberto; Cotugno, Nicola; Giaquinto, Carlo; Nicolosi, Luciana; Bernardi, Stefania; Rossi, Paolo; Douagi, Iyadh; Palma, Paolo

    2012-01-01

    Current evidence on routine immunization of HIV-1 infected children point out the need for a special vaccine schedule in this population. However, optimal strategies for identifying individuals susceptible to infections, and then offering them sustained protection through appropriate immunization schedule, both in terms of timing and number of vaccine doses, still remain to be elucidated. Understanding the degree of immune recovery after HAART initiation is important in guiding administration of routine vaccination in HIV-1 infected children. Although quantitative measures (e.g., CD4+ T-cell counts and immunoglobulin levels) are frequently performed to evaluate immune parameters, these measures do not fully mirror functional immune recovery. Here, we will review the status of single mandatory and recommended vaccines for HIV-1 infected children in relation to immune recovery after HAART initiation with the aim of identifying new means to help design personalized vaccine schedules for this population. PMID:22906931

  8. Heterologous prime-boost-boost immunisation of Chinese cynomolgus macaques using DNA and recombinant poxvirus vectors expressing HIV-1 virus-like particles

    PubMed Central

    2011-01-01

    Background There is renewed interest in the development of poxvirus vector-based HIV vaccines due to the protective effect observed with repeated recombinant canarypox priming with gp120 boosting in the recent Thai placebo-controlled trial. This study sought to investigate whether a heterologous prime-boost-boost vaccine regimen in Chinese cynomolgus macaques with a DNA vaccine and recombinant poxviral vectors expressing HIV virus-like particles bearing envelopes derived from the most prevalent clades circulating in sub-Saharan Africa, focused the antibody response to shared neutralising epitopes. Methods Three Chinese cynomolgus macaques were immunised via intramuscular injections using a regimen composed of a prime with two DNA vaccines expressing clade A Env/clade B Gag followed by boosting with recombinant fowlpox virus expressing HIV-1 clade D Gag, Env and cholera toxin B subunit followed by the final boost with recombinant modified vaccinia virus Ankara expressing HIV-1 clade C Env, Gag and human complement protein C3d. We measured the macaque serum antibody responses by ELISA, enumerated T cell responses by IFN-γ ELISpot and assessed seroneutralisation of HIV-1 using the TZM-bl β-galactosidase assay with primary isolates of HIV-1. Results This study shows that large and complex synthetic DNA sequences can be successfully cloned in a single step into two poxvirus vectors: MVA and FPV and the recombinant poxviruses could be grown to high titres. The vaccine candidates showed appropriate expression of recombinant proteins with the formation of authentic HIV virus-like particles seen on transmission electron microscopy. In addition the b12 epitope was shown to be held in common by the vaccine candidates using confocal immunofluorescent microscopy. The vaccine candidates were safely administered to Chinese cynomolgus macaques which elicited modest T cell responses at the end of the study but only one out of the three macaques elicited an HIV-specific antibody

  9. HIV-1 vaccine antibody induction against a variable region of HIV-1: a possible link to protective immunity?

    PubMed

    Bauer, Gerhard

    2013-05-01

    Evaluation of: Liao H, Bonsignori M, Alam M et al. Vaccine induction of antibodies against a structurally heterogeneous site of immune pressure within HIV-1 envelope protein variable regions 1 and 2. Immunity 38, 176-186 (2013). In 2009, results from the Phase III HIV-1 vaccine clinical trial RV144 applying a prime/boost regimen with a canarypox vaccine vector ALVAC-HIV plus the AIDSVAX B/E subunit envelope vaccine conducted in Thailand were reported. The priming canarypox vector carried the HIV-1 vaccine genes gp120 linked to the transmembrane-anchoring portion of subtype B gp41, HIV-1 Gag and protease; the boosting vaccine was composed of clades B and E of HIV-1 gp120. A 31.2% vaccine efficacy could be seen in this trial, an encouraging result in HIV-1 vaccine research that had been previously plagued with little clinical efficacy. In this paper, results from tests of four monoclonal antibodies isolated from RV144 vaccinees are reported. The antibodies recognize a certain HIV-1 envelope residue (169), neutralize laboratory-adapted HIV-1 strains and mediate killing of CD4(+) cells infected with HIV-1 laboratory isolates. Crystal structure analysis suggests that the recognized HIV-1 envelope epitope can exist in different conformations. It is thought that the immune pressure elicited by the monoclonal antibodies targets a HIV-1 envelope region with variable sequence structure.

  10. HIV-1 evades innate immune recognition through specific cofactor recruitment

    NASA Astrophysics Data System (ADS)

    Rasaiyaah, Jane; Tan, Choon Ping; Fletcher, Adam J.; Price, Amanda J.; Blondeau, Caroline; Hilditch, Laura; Jacques, David A.; Selwood, David L.; James, Leo C.; Noursadeghi, Mahdad; Towers, Greg J.

    2013-11-01

    Human immunodeficiency virus (HIV)-1 is able to replicate in primary human macrophages without stimulating innate immunity despite reverse transcription of genomic RNA into double-stranded DNA, an activity that might be expected to trigger innate pattern recognition receptors. We reasoned that if correctly orchestrated HIV-1 uncoating and nuclear entry is important for evasion of innate sensors then manipulation of specific interactions between HIV-1 capsid and host factors that putatively regulate these processes should trigger pattern recognition receptors and stimulate type 1 interferon (IFN) secretion. Here we show that HIV-1 capsid mutants N74D and P90A, which are impaired for interaction with cofactors cleavage and polyadenylation specificity factor subunit 6 (CPSF6) and cyclophilins (Nup358 and CypA), respectively, cannot replicate in primary human monocyte-derived macrophages because they trigger innate sensors leading to nuclear translocation of NF-κB and IRF3, the production of soluble type 1 IFN and induction of an antiviral state. Depletion of CPSF6 with short hairpin RNA expression allows wild-type virus to trigger innate sensors and IFN production. In each case, suppressed replication is rescued by IFN-receptor blockade, demonstrating a role for IFN in restriction. IFN production is dependent on viral reverse transcription but not integration, indicating that a viral reverse transcription product comprises the HIV-1 pathogen-associated molecular pattern. Finally, we show that we can pharmacologically induce wild-type HIV-1 infection to stimulate IFN secretion and an antiviral state using a non-immunosuppressive cyclosporine analogue. We conclude that HIV-1 has evolved to use CPSF6 and cyclophilins to cloak its replication, allowing evasion of innate immune sensors and induction of a cell-autonomous innate immune response in primary human macrophages.

  11. Structure and immune recognition of trimeric prefusion HIV-1 Env

    PubMed Central

    Pancera, Marie; Zhou, Tongqing; Druz, Aliaksandr; Georgiev, Ivelin S.; Soto, Cinque; Gorman, Jason; Huang, Jinghe; Acharya, Priyamvada; Chuang, Gwo-Yu; Ofek, Gilad; Stewart-Jones, Guillaume B. E.; Stuckey, Jonathan; Bailer, Robert T.; Joyce, M. Gordon; Louder, Mark K.; Tumba, Nancy; Yang, Yongping; Zhang, Baoshan; Cohen, Myron S.; Haynes, Barton F.; Mascola, John R.; Morris, Lynn; Munro, James B.; Blanchard, Scott C.; Mothes, Walther; Connors, Mark; Kwong, Peter D.

    2015-01-01

    The HIV-1-envelope (Env) spike, comprising three gp120 and three gp41 subunits, is a conformational machine that facilitates HIV-1 entry by rearranging from a mature unliganded state, through receptor-bound intermediates, to a postfusion state. As the sole viral antigen on the HIV-1-virion surface, Env is both the target of neutralizing antibodies and a focus of vaccine efforts. Here we report the structure at 3.5-Å resolution for an HIV-1-Env trimer captured in a mature closed state by antibodies PGT122 and 35O22. This structure reveals the prefusion conformation of gp41, indicates rearrangements needed for fusion activation, and defines parameters of immune evasion and immune recognition. Prefusion gp41 encircles N- and C-terminal strands of gp120 with four helices that form a membrane-proximal collar, fastened by insertion of a fusion peptide-proximal methionine into a gp41-tryptophan clasp. Spike rearrangements required for entry likely involve opening the clasp and expelling the termini. N-linked glycosylation and sequence-variable regions cover the prefusion closed spike: we used chronic cohorts to map the prevalence and location of effective HIV-1-neutralizing responses, which were distinguished by their recognition of N-linked glycan and tolerance for epitope-sequence variation. PMID:25296255

  12. HIV-1 adaptation to NK cell mediated immune pressure

    PubMed Central

    Alter, Galit; Heckerman, David; Schneidewind, Arne; Fadda, Lena; Kadie, Carl M.; Carlson, Jonathan M.; Oniangue-Ndza, Cesar; Martin, Maureen; Li, Bin; Khakoo, Salim I.; Carrington, Mary; Allen, Todd M.; Altfeld, Marcus

    2011-01-01

    Natural Killer (NK) cells play an important role in the control of viral infections, recognizing virally infected cells through a variety of activating and inhibitory receptors1–3. Epidemiological and functional studies have recently suggested that NK cells can also contribute to the control of HIV-1 infection through recognition of virally infected cells by both activating and inhibitory Killer Immunoglobulin-like receptors (KIRs)4–7. However, it remains unknown whether NK cells can directly mediate antiviral immune pressure in vivo in humans. Here we describe KIR-associated amino acid polymorphisms in the HIV-1 sequence of chronically infected individuals on a population level. We show that these KIR-associated HIV-1 sequence polymorphisms can enhance the binding of inhibitory KIRs to HIV-1-infected CD4+ T cells, leading to reduced antiviral activity of KIR+ NK cells. These data demonstrate that KIR+ NK cells can place immunological pressure on HIV-1, and that the virus can evade such NK cell mediated immune pressure by selecting for sequence polymorphisms, as previously described for virus-specific T cells and neutralizing antibodies8. NK cells might therefore play a previously underappreciated role in contributing to viral evolution. PMID:21814282

  13. HIV-1 tuberculosis-associated immune reconstitution inflammatory syndrome.

    PubMed

    Lai, Rachel P J; Meintjes, Graeme; Wilkinson, Robert J

    2016-03-01

    Patients co-infected with HIV-1 and tuberculosis (TB) are at risk of developing TB-associated immune reconstitution inflammatory syndrome (TB-IRIS) following commencement of antiretroviral therapy (ART). TB-IRIS is characterized by transient but severe localized or systemic inflammatory reactions against Mycobacterium tuberculosis antigens. Here, we review the risk factors and clinical management of TB-IRIS, as well as the roles played by different aspects of the immune response in contributing to TB-IRIS pathogenesis.

  14. Recombinant Poxvirus and the Tumor Microenvironment: Oncolysis, Immune Regulation and Immunization

    PubMed Central

    Sharp, Daniel W.; Lattime, Edmund C.

    2016-01-01

    Oncolytic viruses (OVs) are being extensively studied for their potential roles in the development of cancer therapy regimens. In addition to their direct lytic effects, OVs can initiate and drive systemic antitumor immunity indirectly via release of tumor antigen, as well as by encoding and delivering immunostimulatory molecules. This combination makes them an effective platform for the development of immunotherapeutic strategies beyond their primary lytic function. Engineering the viruses to also express tumor-associated antigens (TAAs) allows them to simultaneously serve as therapeutic vaccines, targeting and amplifying an immune response to TAAs. Our group and others have shown that vaccinating intratumorally with a poxvirus that encodes TAAs, in addition to immune stimulatory molecules, can modulate the tumor microenvironment, overcome immune inhibitory pathways, and drive both local and systemic tumor specific immune responses. PMID:28191451

  15. Innate immune reconstitution with suppression of HIV-1

    PubMed Central

    Scully, Eileen P.; Garcia-Beltran, Wilfredo; Palmer, Christine D.; Musante, Chelsey; Rosenberg, Eric; Allen, Todd M.; Bosch, Ronald J.

    2016-01-01

    Progressive HIV-1 infection leads to both profound immune suppression and pathologic inflammation in the majority of infected individuals. While adaptive immune dysfunction, as evidenced by CD4+ T cell depletion and exhaustion, has been extensively studied, less is known about the functional capacity of innate immune cell populations in the context of HIV-1 infection. Given the broad susceptibility to opportunistic infections and the dysregulated inflammation observed in progressive disease, we hypothesized that there would be significant changes in the innate cellular responses. Using a cohort of patients with multiple samplings before and after antiretroviral therapy (ART) initiation, we demonstrated increased responses to innate immune stimuli following viral suppression, as measured by the production of inflammatory cytokines. Plasma viral load itself had the strongest association with this change in innate functional capacity. We further identified epigenetic modifications in the TNFA promoter locus in monocytes that are associated with viremia, suggesting a molecular mechanism for the observed changes in innate immune function following initiation of ART. These data indicate that suppression of HIV-1 viremia is associated with changes in innate cellular function that may in part determine the restoration of protective immune responses. PMID:27158667

  16. Infection with diverse immune-modulating poxviruses elicits different compositional shifts in the mouse gut microbiome

    PubMed Central

    Hernáez, Bruno; Rastrojo, Alberto; Alcamí, Antonio

    2017-01-01

    It is often not possible to demonstrate causality within the context of gut microbiota dysbiosis-linked diseases. Thus, we need a better understanding of the mechanisms whereby an altered host immunophysiology shapes its resident microbiota. In this regard, immune-modulating poxvirus strains and mutants could differentially alter gut mucosal immunity in the context of a natural immune response, providing a controlled natural in vivo setting to deepen our understanding of the immune determinants of microbiome composition. This study represents a proof-of-concept that the use of an existing collection of different immune-modulating poxviruses may represent an innovative tool in gut microbiome research. To this end, 16S rRNA amplicon sequencing and RNAseq transcriptome profiling were employed as proxies for microbiota composition and gut immunophysiological status in the analysis of caecal samples from control mice and mice infected with various poxvirus types. Our results show that different poxvirus species and mutants elicit different shifts in the mice mucosa-associated microbiota and, in some instances, significant concomitant shifts in gut transcriptome profiles, thus providing an initial validation to the proposed model. PMID:28282449

  17. A therapeutic HIV-1 vaccine enhances anti-HIV-1 immune responses in patients under highly active antiretroviral therapy.

    PubMed

    Tung, Frank Y; Tung, Jack K; Pallikkuth, Suresh; Pahwa, Savita; Fischl, Margaret A

    2016-04-27

    HIV-1 specific cellular immunity plays an important role in controlling viral replication. In this first-in-human therapeutic vaccination study, a replication-defective HIV-1 vaccine (HIVAX) was tested in HIV-1 infected participants undergoing highly active antiretroviral therapy (HAART) to enhance anti-HIV immunity (Clinicaltrials.gov, identifier NCT01428596). A010 was a randomized, placebo-controlled trial to evaluate the safety and the immunogenicity of a replication defective HIV-1 vaccine (HIVAX) given as a subcutaneous injection to HIV-1 infected participants who were receiving HAART with HIV-1 viral load <50 copies/ml and CD4 cell count >500 cells/mm(3). HIV-1 specific immune responses were monitored by INF-γ enzyme linked immunospot (Elispot) and intracellular cytokine staining (ICS) assay after vaccination. Following the randomized placebo-controlled vaccination phase, subjects who received HIVAX vaccine and who met eligibility underwent a 12-week analytical antiretroviral treatment interruption (ATI). Viral load was monitored throughout the study. HIVAX was well tolerated in trial participants. Transient grade 1 to 2 (mild to moderate) injection site reactions occurred in 8 of 10 vaccinated participants. HIVAX was immunogenic in all vaccinated participants. The functionality of T cells was significantly enhanced after vaccination. Median viral load (3.45 log10 copies/ml, range of 96-12,830 copies/ml) at the end of the 12-week treatment interruption in HIVAX vaccinated group was significantly lower than the pre-treatment levels. Three vaccinated participants extended ATI for up to 2 years with stable CD4 cells and low viral loads. HIVAX vaccine is generally safe, elicits strong anti-HIV-1 immune responses, and may play an important role in controlling viral load during treatment interruption in HIV-1 infected participants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Gut microbiota diversity predicts immune status in HIV-1 infection.

    PubMed

    Nowak, Piotr; Troseid, Marius; Avershina, Ekatarina; Barqasho, Babilonia; Neogi, Ujjwal; Holm, Kristian; Hov, Johannes R; Noyan, Kajsa; Vesterbacka, Jan; Svärd, Jenny; Rudi, Knut; Sönnerborg, Anders

    2015-11-28

    HIV-1 infection is characterized by altered intestinal barrier, gut microbiota dysbiosis, and systemic inflammation. We hypothesized that changes of the gut microbiota predict immune dysfunction and HIV-1 progression, and that antiretroviral therapy (ART) partially restores the microbiota composition. An observational study including 28 viremic patients, three elite controllers, and nine uninfected controls. Blood and stool samples were collected at baseline and for 19 individuals at follow-up (median 10 months) during ART. Microbiota composition was determined by 16S rRNA sequencing (Illumina MiSeq). Soluble markers of microbial translocation and monocyte activation were analyzed by Limulus Amebocyte Lysate assay or ELISA. Several alpha-diversity measures, including number of observed bacterial species and Shannon index, were significantly lower in viremic patients compared to controls. The alpha diversity correlated with CD4 T-cell counts and inversely with markers of microbial translocation and monocyte activation. In multivariate linear regression, for every age and sex-adjusted increase in the number of bacterial species, the CD4 T-cell count increased with 0.88 (95% confidence interval 0.35-1.41) cells/μl (P = 0.002). After introduction of ART, microbiota alterations persisted with further reduction in alpha diversity. The microbiota composition at the genus level was profoundly altered in viremic patients, both at baseline and after ART, with Prevotella reduced during ART (P < 0.007). Gut microbiota alterations are closely associated with immune dysfunction in HIV-1 patients, and these changes persist during short-term ART. Our data implicate that re-shaping the microbiota may be an adjuvant therapy in patients commencing successful ART.

  19. Induction of Heterologous Tier 2 HIV-1-Neutralizing and Cross-Reactive V1/V2-Specific Antibodies in Rabbits by Prime-Boost Immunization

    PubMed Central

    Townsley, Samantha; Mohamed, Zeinab; Guo, Wenjin; McKenna, Jennifer; Cleveland, Brad; LaBranche, Celia; Beaumont, David; Shen, Xiaoying; Yates, Nicole L.; Pinter, Abraham; Tomaras, Georgia D.; Ferrari, Guido; Montefiori, David C.

    2016-01-01

    ABSTRACT Poxvirus prime-protein boost used in the RV144 trial remains the only immunization strategy shown to elicit a modest level of protection against HIV-1 acquisition in humans. Although neutralizing antibodies (NAb) were generated, they were against sensitive viruses, not the more resistant “tier 2” isolates that dominate circulating strains. Instead, risk reduction correlated with antibodies recognizing epitopes in the V1/V2 region of HIV-1 envelope glycoprotein (Env). Here, we examined whether tier 2 virus NAb and V1/V2-specific non-NAb could be elicited by a poxvirus prime-gp120 boost strategy in a rabbit model. We studied two clade B Envs that differ in multiple parameters, including tissue origin, neutralization sensitivity, and presence of the N197 (N7) glycan that was previously shown to modulate the exposure of conserved epitopes on Env. We demonstrate that immunized rabbits generated cross-reactive neutralizing activities against >50% of the tier 2 global HIV-1 isolates tested. Some of these activities were directed against the CD4 binding site (CD4bs). These rabbits also generated antibodies that recognized protein scaffolds bearing V1/V2 sequences from diverse HIV-1 isolates and mediated antibody-dependent cellular cytotoxicity. However, there are subtle differences in the specificities and the response rates of V1/V2-specific antibodies between animals immunized with different Envs, with or without the N7 glycan. These findings demonstrate that antibody responses that have been correlated with protection against HIV-1 acquisition in humans can be elicited in a preclinical model by a poxvirus prime-gp120 boost strategy and that improvements may be achievable by optimizing the nature of the priming and boosting immunogens. IMPORTANCE The only vaccine approach shown to elicit any protective efficacy against HIV-1 acquisition is based on a poxvirus prime-protein boost regimen (RV144 Thai trial). Reduction of risk was associated with

  20. A Phase I Randomized Therapeutic MVA-B Vaccination Improves the Magnitude and Quality of the T Cell Immune Responses in HIV-1-Infected Subjects on HAART

    PubMed Central

    Gómez, Carmen Elena; Perdiguero, Beatriz; García-Arriaza, Juan; Cepeda, Victoria; Sánchez-Sorzano, Carlos Óscar; Mothe, Beatriz; Jiménez, José Luis; Muñoz-Fernández, María Ángeles; Gatell, Jose M.; López Bernaldo de Quirós, Juan Carlos; Brander, Christian; García, Felipe; Esteban, Mariano

    2015-01-01

    Trial Design Previous studies suggested that poxvirus-based vaccines might be instrumental in the therapeutic HIV field. A phase I clinical trial was conducted in HIV-1-infected patients on highly active antiretroviral therapy (HAART), with CD4 T cell counts above 450 cells/mm3 and undetectable viremia. Thirty participants were randomized (2:1) to receive either 3 intramuscular injections of MVA-B vaccine (coding for clade B HIV-1 Env, Gag, Pol and Nef antigens) or placebo, followed by interruption of HAART. Methods The magnitude, breadth, quality and phenotype of the HIV-1-specific T cell response were assayed by intracellular cytokine staining (ICS) in 22 volunteers pre- and post-vaccination. Results MVA-B vaccine induced newly detected HIV-1-specific CD4 T cell responses and expanded pre-existing responses (mostly against Gag, Pol and Nef antigens) that were high in magnitude, broadly directed and showed an enhanced polyfunctionality with a T effector memory (TEM) phenotype, while maintaining the magnitude and quality of the pre-existing HIV-1-specific CD8 T cell responses. In addition, vaccination also triggered preferential CD8+ T cell polyfunctional responses to the MVA vector antigens that increase in magnitude after two and three booster doses. Conclusion MVA-B vaccination represents a feasible strategy to improve T cell responses in individuals with pre-existing HIV-1-specific immunity. Trial Registration ClinicalTrials.gov NCT01571466 PMID:26544853

  1. Use of an In Vivo FTA Assay to Assess the Magnitude, Functional Avidity and Epitope Variant Cross-Reactivity of T Cell Responses Following HIV-1 Recombinant Poxvirus Vaccination

    PubMed Central

    Wijesundara, Danushka K.; Ranasinghe, Charani; Jackson, Ronald J.; Lidbury, Brett A.; Parish, Christopher R.; Quah, Benjamin J. C.

    2014-01-01

    Qualitative characteristics of cytotoxic CD8+ T cells (CTLs) are important in measuring the effectiveness of CTLs in controlling HIV-1 infections. Indeed, in recent studies patients who are naturally resistant to HIV-1 infections have been shown to possess CTLs that are of high functional avidity and have a high capacity to recognize HIV epitope variants, when compared to HIV-1 infection progressors. When developing efficacious vaccines, assays that can effectively measure CTL quality specifically in vivo are becoming increasingly important. Here we report the use of a recently developed high-throughput multi-parameter technique, known as the fluorescent target array (FTA) assay, to simultaneously measure CTL killing magnitude, functional avidity and epitope variant cross-reactivity in real time in vivo. In the current study we have applied the FTA assay as a screening tool to assess a large cohort of over 20 different HIV-1 poxvirus vaccination strategies in mice. This screen revealed that heterologous poxvirus prime-boost vaccination regimes (i.e., recombinant fowlpox (FPV)-HIV prime followed by a recombinant vaccinia virus (VV)-HIV booster) were the most effective in generating high quality CTL responses in vivo. In conclusion, we have demonstrated how the FTA assay can be utilized as a cost effective screening tool (by reducing the required number of animals by >100 fold), to evaluate a large range of HIV-1 vaccination strategies in terms of CTL avidity and variant cross-reactivity in an in vivo setting. PMID:25170620

  2. 4-1BB ligand enhances tumor-specific immunity of poxvirus vaccines

    PubMed Central

    Kudo-Saito, Chie; Hodge, James W.; Kwak, Heesun; Kim-Schulze, Seunghee; Schlom, Jeffrey; Kaufman, Howard L.

    2007-01-01

    Purpose Recombinant poxvirus vaccines have been explored as tumor vaccines. The immunogenicity of these vaccines can be enhanced by co-expressing costimulatory molecules and tumor-associated antigens. While the B7-CD28 interaction has been most comprehensively investigated, other costimulatory molecules utilize different signaling pathways and might provide further cooperation in T cell priming and survival. 4-1BB (CD137) is a TNF family member and is critical for activation and long-term maintenance of primed T-cells. This study was conducted to determine if a poxvirus expressing the ligand for 4-1BB (4-1BBL) could further improve the immune and therapeutic responses of a previously reported poxvirus vaccine expressing a triad of costimulatory molecules (B7.1, ICAM-1, and LFA-3). Experimental Design A recombinant vaccinia virus expressing 4-1BBL was generated and characterized in an in vitro infection system. This vaccine was then used alone or in combination with a vaccinia virus expressing CEA, B7.1, ICAM-1, and LFA-3 in CEA-transgenic mice bearing established MC38 tumors. Tumor growth and immune responses against CEA and other tumor-associated antigens were determined. The level of anti-apoptotic proteins in responding T cells was determined by flow cytometry on tetramer selected T cells. Results The combination of 4-1BBL with B7.1-based poxvirus vaccination resulted in significantly enhanced therapeutic effects against CEA-expressing tumors in a CEA transgenic mouse model. This was associated with an increased level of CEA-specific CD4+ and CD8+ T cell responses, induction of antigen spreading to p53 and gp70, increased accumulation of CEA-specific T cells in the tumor microenvironment, and increased expression of bcl-XL and bcl-2 in CD4+ and CD8+ T cells in vaccinated mice. Conclusion 4-1BBL cooperates with B7 in enhancing anti-tumor and immunologic responses using a recombinant poxvirus vaccine model. The inclusion of costimulatory molecules targeting

  3. Structural Conservation and Functional Diversity of the Poxvirus Immune Evasion (PIE) Domain Superfamily.

    PubMed

    Nelson, Christopher A; Epperson, Megan L; Singh, Sukrit; Elliott, Jabari I; Fremont, Daved H

    2015-08-28

    Poxviruses encode a broad array of proteins that serve to undermine host immune defenses. Structural analysis of four of these seemingly unrelated proteins revealed the recurrent use of a conserved beta-sandwich fold that has not been observed in any eukaryotic or prokaryotic protein. Herein we propose to call this unique structural scaffolding the PIE (Poxvirus Immune Evasion) domain. PIE domain containing proteins are abundant in chordopoxvirinae, with our analysis identifying 20 likely PIE subfamilies among 33 representative genomes spanning 7 genera. For example, cowpox strain Brighton Red appears to encode 10 different PIEs: vCCI, A41, C8, M2, T4 (CPVX203), and the SECRET proteins CrmB, CrmD, SCP-1, SCP-2, and SCP-3. Characterized PIE proteins all appear to be nonessential for virus replication, and all contain signal peptides for targeting to the secretory pathway. The PIE subfamilies differ primarily in the number, size, and location of structural embellishments to the beta-sandwich core that confer unique functional specificities. Reported ligands include chemokines, GM-CSF, IL-2, MHC class I, and glycosaminoglycans. We expect that the list of ligands and receptors engaged by the PIE domain will grow as we come to better understand how this versatile structural architecture can be tailored to manipulate host responses to infection.

  4. Structural Conservation and Functional Diversity of the Poxvirus Immune Evasion (PIE) Domain Superfamily

    PubMed Central

    Nelson, Christopher A.; Epperson, Megan L.; Singh, Sukrit; Elliott, Jabari I.; Fremont, Daved H.

    2015-01-01

    Poxviruses encode a broad array of proteins that serve to undermine host immune defenses. Structural analysis of four of these seemingly unrelated proteins revealed the recurrent use of a conserved beta-sandwich fold that has not been observed in any eukaryotic or prokaryotic protein. Herein we propose to call this unique structural scaffolding the PIE (Poxvirus Immune Evasion) domain. PIE domain containing proteins are abundant in chordopoxvirinae, with our analysis identifying 20 likely PIE subfamilies among 33 representative genomes spanning 7 genera. For example, cowpox strain Brighton Red appears to encode 10 different PIEs: vCCI, A41, C8, M2, T4 (CPVX203), and the SECRET proteins CrmB, CrmD, SCP-1, SCP-2, and SCP-3. Characterized PIE proteins all appear to be nonessential for virus replication, and all contain signal peptides for targeting to the secretory pathway. The PIE subfamilies differ primarily in the number, size, and location of structural embellishments to the beta-sandwich core that confer unique functional specificities. Reported ligands include chemokines, GM-CSF, IL-2, MHC class I, and glycosaminoglycans. We expect that the list of ligands and receptors engaged by the PIE domain will grow as we come to better understand how this versatile structural architecture can be tailored to manipulate host responses to infection. PMID:26343707

  5. Pandemic HIV-1 Vpu overcomes intrinsic herd immunity mediated by tetherin.

    PubMed

    Iwami, Shingo; Sato, Kei; Morita, Satoru; Inaba, Hisashi; Kobayashi, Tomoko; Takeuchi, Junko S; Kimura, Yuichi; Misawa, Naoko; Ren, Fengrong; Iwasa, Yoh; Aihara, Kazuyuki; Koyanagi, Yoshio

    2015-07-17

    Among the four groups of HIV-1 (M, N, O, and P), HIV-1M alone is pandemic and has rapidly expanded across the world. However, why HIV-1M has caused a devastating pandemic while the other groups remain contained is unclear. Interestingly, only HIV-1M Vpu, a viral protein, can robustly counteract human tetherin, which tethers budding virions. Therefore, we hypothesize that this property of HIV-1M Vpu facilitates human-to-human viral transmission. Adopting a multilayered experimental-mathematical approach, we demonstrate that HIV-1M Vpu confers a 2.38-fold increase in the prevalence of HIV-1 transmission. When Vpu activity is lost, protected human populations emerge (i.e., intrinsic herd immunity develops) through the anti-viral effect of tetherin. We also reveal that all Vpus of transmitted/founder HIV-1M viruses maintain anti-tetherin activity. These findings indicate that tetherin plays the role of a host restriction factor, providing 'intrinsic herd immunity', whereas Vpu has evolved in HIV-1M as a tetherin antagonist.

  6. Mosaic HIV-1 Vaccines Expand the Breadth and Depth of Cellular Immune Responses in Rhesus Monkeys

    PubMed Central

    Barouch, Dan H.; O'Brien, Kara L.; Simmons, Nathaniel L.; King, Sharon L.; Abbink, Peter; Maxfield, Lori F.; Sun, Ying-Hua; La Porte, Annalena; Riggs, Ambryice M.; Lynch, Diana M.; Clark, Sarah L.; Backus, Katherine; Perry, James R.; Seaman, Michael S.; Carville, Angela; Mansfield, Keith G.; Szinger, James J.; Fischer, Will; Muldoon, Mark; Korber, Bette

    2010-01-01

    The worldwide diversity of HIV-1 presents an unprecedented challenge for vaccine development 1-2. Antigens derived from natural HIV-1 sequences have elicited only limited breadth of cellular immune responses in nonhuman primate studies and clinical trials to date. Polyvalent “mosaic” antigens, in contrast, are designed to optimize cellular immunologic coverage of global HIV-1 sequence diversity 3. Here we show that mosaic HIV-1 Gag, Pol, and Env antigens expressed by recombinant, replication-incompetent adenovirus serotype 26 vectors markedly augmented both the breadth and depth without compromising the magnitude of antigen-specific T lymphocyte responses as compared with consensus or natural sequence HIV-1 antigens in rhesus monkeys. Polyvalent mosaic antigens therefore represent a promising strategy to expand cellular immunologic vaccine coverage for genetically diverse pathogens such as HIV-1. PMID:20173752

  7. Mosaic HIV-1 vaccines expand the breadth and depth of cellular immune responses in rhesus monkeys.

    PubMed

    Barouch, Dan H; O'Brien, Kara L; Simmons, Nathaniel L; King, Sharon L; Abbink, Peter; Maxfield, Lori F; Sun, Ying-Hua; La Porte, Annalena; Riggs, Ambryice M; Lynch, Diana M; Clark, Sarah L; Backus, Katherine; Perry, James R; Seaman, Michael S; Carville, Angela; Mansfield, Keith G; Szinger, James J; Fischer, Will; Muldoon, Mark; Korber, Bette

    2010-03-01

    The worldwide diversity of HIV-1 presents an unprecedented challenge for vaccine development. Antigens derived from natural HIV-1 sequences have elicited only a limited breadth of cellular immune responses in nonhuman primate studies and clinical trials to date. Polyvalent 'mosaic' antigens, in contrast, are designed to optimize cellular immunologic coverage of global HIV-1 sequence diversity. Here we show that mosaic HIV-1 Gag, Pol and Env antigens expressed by recombinant, replication-incompetent adenovirus serotype 26 vectors markedly augmented both the breadth and depth without compromising the magnitude of antigen-specific T lymphocyte responses as compared with consensus or natural sequence HIV-1 antigens in rhesus monkeys. Polyvalent mosaic antigens therefore represent a promising strategy to expand cellular immunologic vaccine coverage for genetically diverse pathogens such as HIV-1.

  8. Modulation of innate and adaptive cellular immunity relevant to HIV-1 vaccine design by seminal plasma.

    PubMed

    Selva, Kevin J; Kent, Stephen J; Parsons, Matthew S

    2017-01-28

    Mucosal exposure to HIV-1 infection generally occurs in the presence of semen. Immunomodulation by seminal plasma is well described in the reproductive biology literature. Little is known, however, about the impact of seminal plasma on innate and adaptive anti-HIV-1 cellular immunity. The study investigated the effects of seminal plasma on immune responses considered important for prophylactic HIV-1 vaccine development, namely innate and adaptive cellular immunity mediated by natural killer (NK) cells and T cells, respectively. The ability of seminal plasma to modulate direct, antibody-dependent and cytokine-stimulated NK cell activation was assessed utilizing intracellular cytokine staining. Direct and antibody-dependent cellular cytotoxicity was assessed using lactate dehydrogenase release assays. The effects of seminal plasma on T-cell activation upon stimulation with staphylococcus enterotoxin B or HIV-1 Gag peptides were assessed by intracellular cytokine staining. The impact of seminal plasma on redirected cytolysis mediated by T cells was measured using lactate dehydrogenase release assays. Both direct and antibody-dependent NK cell activation were dramatically impaired by the presence of either HIV-1-uninfected or HIV-1-infected seminal plasma in a dose-dependent manner. Additionally, seminal plasma suppressed both direct and antibody-dependent NK cell-mediated cytolysis, including anti-HIV-1 antibody-dependent cytolysis of gp120-pulsed CEM.NKr-CCR5 cells. Finally, seminal plasma attenuated both HIV-1 Gag-specific and staphylococcus enterotoxin B-induced CTL activation. Semen contains potent immunosuppressors of both NK cell and CD8 T-cell-mediated anti-HIV-1 immune responses. This could impede attempts to provide vaccine-induced immunity to HIV-1.

  9. Antiretroviral treatment effect on immune activation reduces cerebrospinal fluid HIV-1 infection.

    PubMed

    Sinclair, Elizabeth; Ronquillo, Rollie; Lollo, Nicole; Deeks, Steven G; Hunt, Peter; Yiannoutsos, Constantin T; Spudich, Serena; Price, Richard W

    2008-04-15

    To define the effect of antiretroviral therapy (ART) on activation of T cells in cerebrospinal fluid (CSF) and blood, and interactions of this activation with CSF HIV-1 RNA concentrations. Cross-sectional analysis of 14 HIV-negative subjects and 123 neuroasymptomatic HIV-1-infected subjects divided into 3 groups: not on ART (termed "offs"), on ART with plasma HIV-1 RNA >500 copies/mL ("failures"), and on ART with plasma HIV-1 RNA HIV-1, it maintained a coincident relation to CSF HIV-1 in both viremic groups. In addition to correlation with CSF HIV-1 concentrations, CD8 activation in blood and CSF correlated with CSF WBCs and CSF neopterin. Multivariate analysis confirmed the association of blood CD8 T-cell activation, along with plasma HIV-1 RNA and CSF neopterin, with CSF HIV-1 RNA levels. The similarity of CD8 T-cell activation in blood and CSF suggests these cells move from blood to CSF with only minor changes in CD38/HLA-DR expression. Differences in the relation of CD8 activation to HIV-1 concentrations in the blood and CSF in the 2 viremic groups suggest that changes in immune activation not only modulate CSF HIV-1 replication but also contribute to CSF treatment effects. The magnitude of systemic HIV-1 infection and intrathecal macrophage activation are also important determinants of CSF HIV-1 RNA levels.

  10. Pandemic HIV-1 Vpu overcomes intrinsic herd immunity mediated by tetherin

    PubMed Central

    Iwami, Shingo; Sato, Kei; Morita, Satoru; Inaba, Hisashi; Kobayashi, Tomoko; Takeuchi, Junko S.; Kimura, Yuichi; Misawa, Naoko; Ren, Fengrong; Iwasa, Yoh; Aihara, Kazuyuki; Koyanagi, Yoshio

    2015-01-01

    Among the four groups of HIV-1 (M, N, O, and P), HIV-1M alone is pandemic and has rapidly expanded across the world. However, why HIV-1M has caused a devastating pandemic while the other groups remain contained is unclear. Interestingly, only HIV-1M Vpu, a viral protein, can robustly counteract human tetherin, which tethers budding virions. Therefore, we hypothesize that this property of HIV-1M Vpu facilitates human-to-human viral transmission. Adopting a multilayered experimental-mathematical approach, we demonstrate that HIV-1M Vpu confers a 2.38-fold increase in the prevalence of HIV-1 transmission. When Vpu activity is lost, protected human populations emerge (i.e., intrinsic herd immunity develops) through the anti-viral effect of tetherin. We also reveal that all Vpus of transmitted/founder HIV-1M viruses maintain anti-tetherin activity. These findings indicate that tetherin plays the role of a host restriction factor, providing ‘intrinsic herd immunity’, whereas Vpu has evolved in HIV-1M as a tetherin antagonist. PMID:26184634

  11. Maternal plasma and breastmilk viral loads are associated with HIV-1-specific cellular immune responses among HIV-1-exposed, uninfected infants in Kenya

    PubMed Central

    Liu, A Y; Lohman-Payne, B; Chung, M H; Kiarie, J; Kinuthia, J; Slyker, J; Richardson, B; Lehman, D; Farquhar, C; John-Stewart, G

    2015-01-01

    Infants exposed to maternal HIV-1 provide an opportunity to assess correlates of HIV-1-specific interferon (IFN)-γ responses and may be informative in the development of HIV-1 vaccines. HIV-1-infected women with CD4 counts 200–500 cells/mm3 were randomized to short-course zidovudine/nevirapine (ZDV/NVP) or highly active anti-retroviral therapy (HAART) between 2003 and 2005. Maternal plasma and breastmilk HIV-1 RNA and DNA were quantified during the first 6–12 months postpartum. HIV-1 gag peptide-stimulated enzyme-linked immunospot (ELISPOT) assays were conducted in HIV-1-exposed, uninfected infants (EU), and correlates were determined using regression and generalized estimating equations. Among 47 EU infants, 21 (45%) had ≥1 positive ELISPOT result during follow-up. Infants had a median response magnitude of 177 HIV-1-specific spot-forming units (SFU)/106 peripheral blood mononuclear cells (PBMC) [interquartile range (IQR) = 117–287] directed against 2 (IQR = 1–3) gag peptide pools. The prevalence and magnitude of responses did not differ by maternal anti-retroviral (ARV) randomization arm. Maternal plasma HIV-1 RNA levels during pregnancy (P = 0·009) and breastmilk HIV-1 DNA levels at 1 month (P = 0·02) were associated with a higher magnitude of infant HIV-1-specific ELISPOT responses at 1 month postpartum. During follow-up, concurrent breastmilk HIV-1 RNA and DNA (cell-free virus and cell-associated virus, respectively) each were associated positively with magnitude of infant HIV-1-specific responses (P = 0·01). Our data demonstrate the importance of antigenic exposure on the induction of infant HIV-1-specific cellular immune responses in the absence of infection. PMID:25652232

  12. Immune reconstitution and vaccination outcome in HIV-1 infected children: present knowledge and future directions.

    PubMed

    Cagigi, Alberto; Cotugno, Nicola; Giaquinto, Carlo; Nicolosi, Luciana; Bernardi, Stefania; Rossi, Paolo; Douagi, Iyadh; Palma, Paolo

    2012-12-01

    Current evidence on routine immunization of HIV-1 infected children point out the need for a special vaccine schedule in this population. However, optimal strategies for identifying individuals susceptible to infections, and then offering them sustained protection through appropriate immunization schedule, both in terms of timing and number of vaccine doses, still remain to be elucidated. Understanding the degree of immune recovery after HAART initiation is important in guiding administration of routine vaccination in HIV-1 infected children. Although quantitative measures (e.g., CD4+ T-cell counts and immunoglobulin levels) are frequently performed to evaluate immune parameters, these measures do not fully mirror functional immune recovery. Here, we will review the status of single mandatory and recommended vaccines for HIV-1 infected children in relation to immune recovery after HAART initiation with the aim of identifying new means to help design personalized vaccine schedules for this population.

  13. Molecular clock of HIV-1 envelope genes under early immune selection

    DOE PAGES

    Park, Sung Yong; Love, Tanzy M. T.; Perelson, Alan S.; ...

    2016-06-01

    Here, the molecular clock hypothesis that genes or proteins evolve at a constant rate is a key tool to reveal phylogenetic relationships among species. Using the molecular clock, we can trace an infection back to transmission using HIV-1 sequences from a single time point. Whether or not a strict molecular clock applies to HIV-1’s early evolution in the presence of immune selection has not yet been fully examined.

  14. Molecular clock of HIV-1 envelope genes under early immune selection

    SciTech Connect

    Park, Sung Yong; Love, Tanzy M. T.; Perelson, Alan S.; Mack, Wendy J.; Lee, Ha Youn

    2016-06-01

    Here, the molecular clock hypothesis that genes or proteins evolve at a constant rate is a key tool to reveal phylogenetic relationships among species. Using the molecular clock, we can trace an infection back to transmission using HIV-1 sequences from a single time point. Whether or not a strict molecular clock applies to HIV-1’s early evolution in the presence of immune selection has not yet been fully examined.

  15. Immune evasion and counteraction of restriction factors by HIV-1 and other primate lentiviruses.

    PubMed

    Kirchhoff, Frank

    2010-07-22

    Retroviruses have evolved effective strategies to evade the host immune response, such as high variability and latent infection. In addition, primate lentiviruses, such as HIV-1, have acquired several "accessory" genes that antagonize antiviral host restriction factors and facilitate viral immune evasion, thereby allowing continuous and efficient viral replication despite apparently strong innate and acquired immune responses. Here, I summarize some of our current knowledge on the acquisition and function of the viral vif, vpr, vpu, and nef genes, with a particular focus on the evolution and specific properties of pandemic HIV-1 strains that may contribute to their efficient spread and high virulence. Copyright 2010 Elsevier Inc. All rights reserved.

  16. Enhanced Immune Activation Linked to Endotoxemia in HIV-1 Seronegative Men who have Sex with Men

    PubMed Central

    Palmer, Christine D.; Tomassilli, Julia; Sirignano, Michael; Tejeda, Marisol Romero; Arnold, Kelly B.; Che, Denise; Lauffenburger, Douglas A.; Jost, Stephanie; Allen, Todd; Mayer, Kenneth H.; Altfeld, Marcus

    2015-01-01

    Summary This study assessed cellular and soluble markers of immune activation in HIV-1-seronegative men who have sex with men (MSM). MSM immune profiles were characterized by increased expression of CD57 on T cells and endotoxemia. Endotoxin presence was linked to recent high-risk exposure and associated with elevated cytokine levels and decreased CD4/CD8 T cell ratios. Taken together, these data show elevated levels of inflammation linked to periods of endotoxemia resulting in a significantly different immune phenotype in a subset of MSM at high risk of HIV-1 acquisition. PMID:25003719

  17. Population-Level Immune-Mediated Adaptation in HIV-1 Polymerase during the North American Epidemic

    PubMed Central

    Kinloch, Natalie N.; MacMillan, Daniel R.; Le, Anh Q.; Cotton, Laura A.; Bangsberg, David R.; Buchbinder, Susan; Carrington, Mary; Fuchs, Jonathan; Harrigan, P. Richard; Koblin, Beryl; Kushel, Margot; Markowitz, Martin; Mayer, Kenneth; Milloy, M. J.; Schechter, Martin T.; Wagner, Theresa; Walker, Bruce D.; Carlson, Jonathan M.; Poon, Art F. Y.

    2015-01-01

    ABSTRACT Human leukocyte antigen (HLA) class I-associated polymorphisms in HIV-1 that persist upon transmission to HLA-mismatched hosts may spread in the population as the epidemic progresses. Transmission of HIV-1 sequences containing such adaptations may undermine cellular immune responses to the incoming virus in future hosts. Building upon previous work, we investigated the extent of HLA-associated polymorphism accumulation in HIV-1 polymerase (Pol) through comparative analysis of linked HIV-1/HLA class I genotypes sampled during historic (1979 to 1989; n = 338) and modern (2001 to 2011; n = 278) eras from across North America (Vancouver, BC, Canada; Boston, MA; New York, NY; and San Francisco, CA). Phylogenies inferred from historic and modern HIV-1 Pol sequences were star-like in shape, with an inferred most recent common ancestor (epidemic founder virus) sequence nearly identical to the modern North American subtype B consensus sequence. Nevertheless, modern HIV-1 Pol sequences exhibited roughly 2-fold-higher patristic (tip-to-tip) genetic distances than historic sequences, with HLA pressures likely driving ongoing diversification. Moreover, the frequencies of published HLA-associated polymorphisms in individuals lacking the selecting HLA class I allele was on average ∼2.5-fold higher in the modern than in the historic era, supporting their spread in circulation, though some remained stable in frequency during this time. Notably, polymorphisms restricted by protective HLA alleles appear to be spreading to a greater relative extent than others, though these increases are generally of modest absolute magnitude. However, despite evidence of polymorphism spread, North American hosts generally remain at relatively low risk of acquiring an HIV-1 polymerase sequence substantially preadapted to their HLA profiles, even in the present era. IMPORTANCE HLA class I-restricted cytotoxic T-lymphocyte (CTL) escape mutations in HIV-1 that persist upon transmission may

  18. Broadly Neutralizing Antibodies against HIV-1 As a Novel Aspect of the Immune Response.

    PubMed

    Shcherbakov, D N; Bakulina, A Y; Karpenko, L I; Ilyichev, A A

    2015-01-01

    The human immunodeficiency virus-1 (HIV-1) has the ability to evade the adaptive immune response due to high mutation rates. Soon after the discovery of HIV-1, it was originally proposed that neutralizing of antibodies to the virus occurs rarely or cannot be elicited at all. In the 1990s, there appeared reports that sera of select HIV-1-infected individuals contained antibodies capable of neutralizing different virus subtypes. Such antibodies were named broadly neutralizing antibodies (bNAbs). Since 2009, the development of new cell technologies has intensified research efforts directed at identifying new bNAbs with a neutralization potency of over 90% of primary HIV-1 isolates. These antibodies have unique characteristics which include high levels of somatic mutations and unusually long variable loops that penetrate through the glycan shield of HIV-1 Env to contact the protein surface. In this review, we will attempt to summarize the latest data on bNAbs against HIV-1 in terms of their interactions with the sites of vulnerability on HIV-1 glycoproteins.

  19. Broadly Neutralizing Antibodies against HIV-1 As a Novel Aspect of the Immune Response

    PubMed Central

    Shcherbakov, D. N.; Bakulina, A. Y.; Karpenko, L. I.; Ilyichev, A. A.

    2015-01-01

    The human immunodeficiency virus-1 (HIV-1) has the ability to evade the adaptive immune response due to high mutation rates. Soon after the discovery of HIV-1, it was originally proposed that neutralizing of antibodies to the virus occurs rarely or cannot be elicited at all. In the 1990s, there appeared reports that sera of select HIV-1-infected individuals contained antibodies capable of neutralizing different virus subtypes. Such antibodies were named broadly neutralizing antibodies (bNAbs). Since 2009, the development of new cell technologies has intensified research efforts directed at identifying new bNAbs with a neutralization potency of over 90% of primary HIV-1 isolates. These antibodies have unique characteristics which include high levels of somatic mutations and unusually long variable loops that penetrate through the glycan shield of HIV-1 Env to contact the protein surface. In this review, we will attempt to summarize the latest data on bNAbs against HIV-1 in terms of their interactions with the sites of vulnerability on HIV-1 glycoproteins. PMID:26798488

  20. Antiretroviral Treatment Effect on Immune Activation Reduces Cerebrospinal Fluid HIV-1 Infection

    PubMed Central

    Sinclair, Elizabeth; Ronquillo, Rollie; Lollo, Nicole; Deeks, Steven G.; Hunt, Peter; Yiannoutsos, Constantin T.; Spudich, Serena; Price, Richard W.

    2012-01-01

    Objective To define the effect of antiretroviral therapy (ART) on activation of T cells in cerebrospinal fluid (CSF) and blood, and interactions of this activation with CSF HIV-1 RNA concentrations. Design Cross-sectional analysis of 14 HIV-negative subjects and 123 neuroasymptomatic HIV-1–infected subjects divided into 3 groups: not on ART (termed “offs”), on ART with plasma HIV-1 RNA >500 copies/mL (“failures”), and on ART with plasma HIV-1 RNA ≤500 copies/mL (“successes”). T-cell activation was measured by coexpression of CD38 and human leukocyte antigen DR (HLA-DR). Other measurements included CSF neopterin and white blood cell (WBC) counts. Results CD8 T-cell activation in CSF and blood was highly correlated across all subjects and was highest in the offs, lower in the failures, and lower still in the successes. While CD8 activation was reduced in failures compared to offs across the range of plasma HIV-1, it maintained a coincident relation to CSF HIV-1 in both viremic groups. In addition to correlation with CSF HIV-1 concentrations, CD8 activation in blood and CSF correlated with CSF WBCs and CSF neopterin. Multivariate analysis confirmed the association of blood CD8 T-cell activation, along with plasma HIV-1 RNA and CSF neopterin, with CSF HIV-1 RNA levels. Conclusions The similarity of CD8 T-cell activation in blood and CSF suggests these cells move from blood to CSF with only minor changes in CD38/HLA-DR expression. Differences in the relation of CD8 activation to HIV-1 concentrations in the blood and CSF in the 2 viremic groups suggest that changes in immune activation not only modulate CSF HIV-1 replication but also contribute to CSF treatment effects. The magnitude of systemic HIV-1 infection and intrathecal macrophage activation are also important determinants of CSF HIV-1 RNA levels. PMID:18362693

  1. Reconstructing the temporal progression of HIV-1 immune response pathways

    PubMed Central

    Jain, Siddhartha; Arrais, Joel; Venkatachari, Narasimhan J.; Ayyavoo, Velpandi; Bar-Joseph, Ziv

    2016-01-01

    Motivation: Most methods for reconstructing response networks from high throughput data generate static models which cannot distinguish between early and late response stages. Results: We present TimePath, a new method that integrates time series and static datasets to reconstruct dynamic models of host response to stimulus. TimePath uses an Integer Programming formulation to select a subset of pathways that, together, explain the observed dynamic responses. Applying TimePath to study human response to HIV-1 led to accurate reconstruction of several known regulatory and signaling pathways and to novel mechanistic insights. We experimentally validated several of TimePaths’ predictions highlighting the usefulness of temporal models. Availability and Implementation: Data, Supplementary text and the TimePath software are available from http://sb.cs.cmu.edu/timepath Contact: zivbj@cs.cmu.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27307624

  2. Immune-Based Approaches to the Prevention of Mother-to-child-Transmission of HIV-1: Active and Passive Immunization

    PubMed Central

    Lohman-Payne, Barb; Slyker, Jennifer; Rowland-Jones, Sarah L.

    2010-01-01

    Synopsis Despite more than two decades of research, an effective vaccine that can prevent HIV-1 infection in populations exposed to the virus remains elusive. In the pursuit of an HIV-1 vaccine, does prevention of exposure to maternal HIV-1 in utero, at birth or in early life through breast-milk require special consideration? In this article we will review what is known about the immune mechanisms of susceptibility and resistance to mother-to-child transmission (MTCT) of HIV-1 and will summarise studies that have used passive or active immunisation strategies to interrupt -MTCT of HIV-1. We will also describe potentially modifiable infectious co-factors that may enhance transmission and/or disease progression (especially in the developing world). Ultimately an effective prophylactic vaccine against HIV-1 infection will need to be deployed as part of the Extended Programme of Immunisation (EPI) recommended by the World Health Organisation (WHO) for use in developing countries, so it is important to understand how the infant immune system responds to HIV-1 antigens, both in natural infection and presented by candidate vaccines. PMID:21078451

  3. IMMUNE ACTIVATION AND PAEDIATRIC HIV-1 DISEASE OUTCOME

    PubMed Central

    Roider, J; Muenchhoff, M; Goulder, PJR

    2016-01-01

    Purpose of review The paediatric HIV epidemic is changing. Over the past decade, new infections have substantially reduced whilst access to antiretroviral therapy (ART) has increased. Overall this success means that numbers of children living with HIV are climbing. In addition, the problems in adults of chronic inflammation resulting from persistent immune activation even following ART-mediated suppression of viral replication are magnified in children infected from birth. Recent findings Features of immune ontogeny favor low immune activation in early life, whilst specific aspects of paediatric HIV infection tend to increase it. A subset of ART-naïve non-progressing children exists in whom normal CD4 counts are maintained in the setting of persistent high viremia and yet in the context of low immune activation. This sooty mangabey-like phenotype contrasts with non-progressing adult infection characterized by the expression of protective HLA class I molecules and low viral load. The particular factors contributing to raised or lowered immune activation in paediatric infection, and that ultimately influence disease outcome, are discussed. Summary Novel strategies to circumvent the unwanted long-term consequences of HIV infection may be possible in children in whom natural immune ontogeny in early life militates against immune activation. Defining the mechanisms underlying low immune activation in natural HIV infection would have applications beyond paediatric HIV. PMID:26679413

  4. Proof-of-Principle for Immune Control of Global HIV-1 Reactivation In Vivo.

    PubMed

    Smith, Nicola M G; Mlcochova, Petra; Watters, Sarah A; Aasa-Chapman, Marlene M I; Rabin, Neil; Moore, Sally; Edwards, Simon G; Garson, Jeremy A; Grant, Paul R; Ferns, R Bridget; Kashuba, Angela; Mayor, Neema P; Schellekens, Jennifer; Marsh, Steven G E; McMichael, Andrew J; Perelson, Alan S; Pillay, Deenan; Goonetilleke, Nilu; Gupta, Ravindra K

    2015-07-01

    Emerging data relating to human immunodeficiency virus type 1 (HIV-1) cure suggest that vaccination to stimulate the host immune response, particularly cytotoxic cells, may be critical to clearing of reactivated HIV-1-infected cells. However, evidence for this approach in humans is lacking, and parameters required for a vaccine are unknown because opportunities to study HIV-1 reactivation are rare. We present observations from a HIV-1 elite controller, not treated with combination antiretroviral therapy, who experienced viral reactivation following treatment for myeloma with melphalan and autologous stem cell transplantation. Mathematical modeling was performed using a standard viral dynamic model. Enzyme-linked immunospot, intracellular cytokine staining, and tetramer staining were performed on peripheral blood mononuclear cells; in vitro CD8 T-cell-mediated control of virion production by autologous CD4 T cells was quantified; and neutralizing antibody titers were measured. Viral rebound was measured at 28,000 copies/mL on day 13 post-transplant before rapid decay to <50 copies/mL in 2 distinct phases with t1/2 of 0.71 days and 4.1 days. These kinetics were consistent with an expansion of cytotoxic effector cells and killing of productively infected CD4 T cells. Following transplantation, innate immune cells, including natural killer cells, recovered with virus rebound. However, most striking was the expansion of highly functional HIV-1-specific cytotoxic CD8 T cells, at numbers consistent with those applied in modeling, as virus control was regained. These observations provide evidence that the human immune response is capable of controlling coordinated global HIV-1 reactivation, remarkably with potency equivalent to combination antiretroviral therapy. These data will inform design of vaccines for use in HIV-1 curative interventions. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

  5. Proof-of-Principle for Immune Control of Global HIV-1 Reactivation In Vivo

    PubMed Central

    Smith, Nicola M. G.; Mlcochova, Petra; Watters, Sarah A.; Aasa-Chapman, Marlene M. I.; Rabin, Neil; Moore, Sally; Edwards, Simon G.; Garson, Jeremy A.; Grant, Paul R.; Ferns, R. Bridget; Kashuba, Angela; Mayor, Neema P.; Schellekens, Jennifer; Marsh, Steven G. E.; McMichael, Andrew J.; Perelson, Alan S.; Pillay, Deenan; Goonetilleke, Nilu; Gupta, Ravindra K.

    2015-01-01

    Background. Emerging data relating to human immunodeficiency virus type 1 (HIV-1) cure suggest that vaccination to stimulate the host immune response, particularly cytotoxic cells, may be critical to clearing of reactivated HIV-1–infected cells. However, evidence for this approach in humans is lacking, and parameters required for a vaccine are unknown because opportunities to study HIV-1 reactivation are rare. Methods. We present observations from a HIV-1 elite controller, not treated with combination antiretroviral therapy, who experienced viral reactivation following treatment for myeloma with melphalan and autologous stem cell transplantation. Mathematical modeling was performed using a standard viral dynamic model. Enzyme-linked immunospot, intracellular cytokine staining, and tetramer staining were performed on peripheral blood mononuclear cells; in vitro CD8 T-cell–mediated control of virion production by autologous CD4 T cells was quantified; and neutralizing antibody titers were measured. Results. Viral rebound was measured at 28 000 copies/mL on day 13 post-transplant before rapid decay to <50 copies/mL in 2 distinct phases with t1/2 of 0.71 days and 4.1 days. These kinetics were consistent with an expansion of cytotoxic effector cells and killing of productively infected CD4 T cells. Following transplantation, innate immune cells, including natural killer cells, recovered with virus rebound. However, most striking was the expansion of highly functional HIV-1–specific cytotoxic CD8 T cells, at numbers consistent with those applied in modeling, as virus control was regained. Conclusions. These observations provide evidence that the human immune response is capable of controlling coordinated global HIV-1 reactivation, remarkably with potency equivalent to combination antiretroviral therapy. These data will inform design of vaccines for use in HIV-1 curative interventions. PMID:25778749

  6. Neutralizing antibodies to HIV-1 induced by immunization

    PubMed Central

    McCoy, Laura E.

    2013-01-01

    Most neutralizing antibodies act at the earliest steps of viral infection and block interaction of the virus with cellular receptors to prevent entry into host cells. The inability to induce neutralizing antibodies to HIV has been a major obstacle to HIV vaccine research since the early days of the epidemic. However, in the past three years, the definition of a neutralizing antibody against HIV has been revolutionized by the isolation of extremely broad and potent neutralizing antibodies from HIV-infected individuals. Considerable hurdles remain for inducing neutralizing antibodies to a protective level after immunization. Meanwhile, novel technologies to bypass the induction of antibodies are being explored to provide prophylactic antibody-based interventions. This review addresses the challenge of inducing HIV neutralizing antibodies upon immunization and considers notable recent advances in the field. A greater understanding of the successes and failures for inducing a neutralizing response upon immunization is required to accelerate the development of an effective HIV vaccine. PMID:23401570

  7. Structure and immune recognition of trimeric pre-fusion HIV-1 Env

    SciTech Connect

    Pancera, Marie; Zhou, Tongqing; Druz, Aliaksandr; Georgiev, Ivelin S.; Soto, Cinque; Gorman, Jason; Huang, Jinghe; Acharya, Priyamvada; Chuang, Gwo-Yu; Ofek, Gilad; Stewart-Jones, Guillaume B. E.; Stuckey, Jonathan; Bailer, Robert T.; Joyce, M. Gordon; Louder, Mark K.; Tumba, Nancy; Yang, Yongping; Zhang, Baoshan; Cohen, Myron S.; Haynes, Barton F.; Morris, Lynn; Munro, James B.; Blanchard, Scott C.; Mothes, Walther; Connors, Mark; Kwong, Peter D.

    2014-10-08

    The human immunodeficiency virus type 1 (HIV-1) envelope (Env) spike, comprising three gp120 and three gp41 subunits, is a conformational machine that facilitates HIV-1 entry by rearranging from a mature unliganded state, through receptor-bound intermediates, to a post-fusion state. As the sole viral antigen on the HIV-1 virion surface, Env is both the target of neutralizing antibodies and a focus of vaccine efforts. Here we report the structure at 3.5 Å resolution for an HIV-1 Env trimer captured in a mature closed state by antibodies PGT122 and 35O22. This structure reveals the pre-fusion conformation of gp41, indicates rearrangements needed for fusion activation, and defines parameters of immune evasion and immune recognition. Pre-fusion gp41 encircles amino- and carboxy-terminal strands of gp120 with four helices that form a membrane-proximal collar, fastened by insertion of a fusion peptide-proximal methionine into a gp41-tryptophan clasp. Spike rearrangements required for entry involve opening the clasp and expelling the termini. In conclusion, N-linked glycosylation and sequence-variable regions cover the pre-fusion closed spike; we used chronic cohorts to map the prevalence and location of effective HIV-1-neutralizing responses, which were distinguished by their recognition of N-linked glycan and tolerance for epitope-sequence variation.

  8. Structure and immune recognition of trimeric pre-fusion HIV-1 Env

    DOE PAGES

    Pancera, Marie; Zhou, Tongqing; Druz, Aliaksandr; ...

    2014-10-08

    The human immunodeficiency virus type 1 (HIV-1) envelope (Env) spike, comprising three gp120 and three gp41 subunits, is a conformational machine that facilitates HIV-1 entry by rearranging from a mature unliganded state, through receptor-bound intermediates, to a post-fusion state. As the sole viral antigen on the HIV-1 virion surface, Env is both the target of neutralizing antibodies and a focus of vaccine efforts. Here we report the structure at 3.5 Å resolution for an HIV-1 Env trimer captured in a mature closed state by antibodies PGT122 and 35O22. This structure reveals the pre-fusion conformation of gp41, indicates rearrangements needed formore » fusion activation, and defines parameters of immune evasion and immune recognition. Pre-fusion gp41 encircles amino- and carboxy-terminal strands of gp120 with four helices that form a membrane-proximal collar, fastened by insertion of a fusion peptide-proximal methionine into a gp41-tryptophan clasp. Spike rearrangements required for entry involve opening the clasp and expelling the termini. In conclusion, N-linked glycosylation and sequence-variable regions cover the pre-fusion closed spike; we used chronic cohorts to map the prevalence and location of effective HIV-1-neutralizing responses, which were distinguished by their recognition of N-linked glycan and tolerance for epitope-sequence variation.« less

  9. The impact of inflammation and immune activation on B cell differentiation during HIV-1 infection.

    PubMed

    Ruffin, Nicolas; Thang, Pham Hong; Rethi, Bence; Nilsson, Anna; Chiodi, Francesca

    2011-01-01

    One important pathogenic feature of human immunodeficiency virus (HIV)-1 infection is chronic immune activation and impaired survival of T and B cells. A decline of resting memory B cells was reported to occur in both children and adults infected with HIV-1; these cells are responsible for maintaining an adequate serological response to antigens previously encountered in life through natural infection or vaccination. Further understanding of the mechanisms leading to impaired B cell differentiation and germinal center reaction might be essential to design new HIV vaccines and therapies that could improve humoral immune responses in HIV-1 infected individuals. In the present article we summarize the literature and present our view on critical mechanisms of B cell development impaired during HIV-1 infection. We also discuss the impact of microbial translocation, a driving force for persistent inflammation during HIV-1 infection, on survival of terminally differentiated B cells and how the altered expression of cytokines/chemokines pivotal for communication between T and B cells in lymphoid tissues may impair formation of memory B cells.

  10. The Impact of Inflammation and Immune Activation on B Cell Differentiation during HIV-1 Infection

    PubMed Central

    Ruffin, Nicolas; Thang, Pham Hong; Rethi, Bence; Nilsson, Anna; Chiodi, Francesca

    2012-01-01

    One important pathogenic feature of human immunodeficiency virus (HIV)-1 infection is chronic immune activation and impaired survival of T and B cells. A decline of resting memory B cells was reported to occur in both children and adults infected with HIV-1; these cells are responsible for maintaining an adequate serological response to antigens previously encountered in life through natural infection or vaccination. Further understanding of the mechanisms leading to impaired B cell differentiation and germinal center reaction might be essential to design new HIV vaccines and therapies that could improve humoral immune responses in HIV-1 infected individuals. In the present article we summarize the literature and present our view on critical mechanisms of B cell development impaired during HIV-1 infection. We also discuss the impact of microbial translocation, a driving force for persistent inflammation during HIV-1 infection, on survival of terminally differentiated B cells and how the altered expression of cytokines/chemokines pivotal for communication between T and B cells in lymphoid tissues may impair formation of memory B cells. PMID:22566879

  11. The Effect of Chloroquine on Immune Activation and Interferon Signatures Associated with HIV-1.

    PubMed

    Jacobson, Jeffrey M; Bosinger, Steven E; Kang, Minhee; Belaunzaran-Zamudio, Pablo; Matining, Roy M; Wilson, Cara C; Flexner, Charles; Clagett, Brian; Plants, Jill; Read, Sarah; Purdue, Lynette; Myers, Laurie; Boone, Linda; Tebas, Pablo; Kumar, Princy; Clifford, David; Douek, Daniel; Silvestri, Guido; Landay, Alan L; Lederman, Michael M

    2016-07-01

    Immune activation associated with HIV-1 infection contributes to morbidity and mortality. We studied whether chloroquine, through Toll-like receptor (TLR) antagonist properties, could reduce immune activation thought to be driven by TLR ligands, such as gut-derived bacterial elements and HIV-1 RNAs. AIDS Clinical Trials Group A5258 was a randomized, double-blind, placebo-controlled study in 33 HIV-1-infected participants off antiretroviral therapy (ART) and 37 participants on ART. Study participants in each cohort were randomized 1:1 to receive chloroquine 250 mg orally for the first 12 weeks then cross over to placebo for 12 weeks or placebo first and then chloroquine. Combining the periods of chloroquine use in both arms of the on-ART cohort yielded a modest reduction in the proportions of CD8 T cells co-expressing CD38 and DR (median decrease = 3.0%, p = .003). The effect on immune activation in the off-ART cohort was likely confounded by increased plasma HIV-1 RNA during chloroquine administration (median 0.29 log10 increase, p < .001). Transcriptional analyses in the off-ART cohort showed decreased expression of interferon-stimulated genes in 5 of 10 chloroquine-treated participants and modest decreases in CD38 and CCR5 RNAs in all chloroquine-treated participants. Chloroquine modestly reduced immune activation in ART-treated HIV-infected participants. Clinical Trials Registry Number: NCT00819390.

  12. Mucosal Vaccination Overcomes the Barrier to Recombinant Vaccinia Immunization Caused by Preexisting Poxvirus Immunity

    NASA Astrophysics Data System (ADS)

    Belyakov, Igor M.; Moss, Bernard; Strober, Warren; Berzofsky, Jay A.

    1999-04-01

    Overcoming preexisting immunity to vaccinia virus in the adult population is a key requirement for development of otherwise potent recombinant vaccinia vaccines. Based on our observation that s.c. immunization with vaccinia induces cellular and antibody immunity to vaccinia only in systemic lymphoid tissue and not in mucosal sites, we hypothesized that the mucosal immune system remains naive to vaccinia and therefore amenable to immunization with recombinant vaccinia vectors despite earlier vaccinia exposure. We show that mucosal immunization of vaccinia-immune BALB/c mice with recombinant vaccinia expressing HIV gp160 induced specific serum antibody and strong HIV-specific cytotoxic T lymphocyte responses. These responses occurred not only in mucosal but also in systemic lymphoid tissue, whereas systemic immunization was ineffective under these circumstances. In this context, intrarectal immunization was more effective than intranasal immunization. Boosting with a second dose of recombinant vaccinia was also more effective via the mucosal route. The systemic HIV-specific cytotoxic T lymphocyte response was enhanced by coadministration of IL-12 at the mucosal site. These results also demonstrate the independent compartmentalization of the mucosal versus systemic immune systems and the asymmetric trafficking of lymphocytes between them. This approach to circumvent previous vaccinia immunity may be useful for induction of protective immunity against infectious diseases and cancer in the sizable populations with preexisting immunity to vaccinia from smallpox vaccination.

  13. Advancing Toward HIV-1 Vaccine Efficacy through the Intersections of Immune Correlates

    PubMed Central

    Tomaras, Georgia D.; Haynes, Barton F.

    2013-01-01

    Interrogating immune correlates of infection risk for efficacious and non-efficacious HIV-1 vaccine clinical trials have provided hypotheses regarding the mechanisms of induction of protective immunity to HIV-1. To date, there have been six HIV-1 vaccine efficacy trials (VAX003, Vaxgen, Inc., San Francisco, CA, USA), VAX004 (Vaxgen, Inc.), HIV-1 Vaccine Trials Network (HVTN) 502 (Step), HVTN 503 (Phambili), RV144 (sponsored by the U.S. Military HIV Research Program, MHRP) and HVTN 505). Cellular, humoral, host genetic and virus sieve analyses of these human clinical trials each can provide information that may point to potentially protective mechanisms for vaccine-induced immunity. Critical to staying on the path toward development of an efficacious vaccine is utilizing information from previous human and non-human primate studies in concert with new discoveries of basic HIV-1 host-virus interactions. One way that past discoveries from correlate analyses can lead to novel inventions or new pathways toward vaccine efficacy is to examine the intersections where different components of the correlate analyses overlap (e.g., virus sieve analysis combined with humoral correlates) that can point to mechanistic hypotheses. Additionally, differences in durability among vaccine-induced T- and B-cell responses indicate that time post-vaccination is an important variable. Thus, understanding the nature of protective responses, the degree to which such responses have, or have not, as yet, been induced by previous vaccine trials and the design of strategies to induce durable T- and B-cell responses are critical to the development of a protective HIV-1 vaccine. PMID:24932411

  14. Molecular clock of HIV-1 envelope genes under early immune selection.

    PubMed

    Park, Sung Yong; Love, Tanzy M T; Perelson, Alan S; Mack, Wendy J; Lee, Ha Youn

    2016-06-01

    The molecular clock hypothesis that genes or proteins evolve at a constant rate is a key tool to reveal phylogenetic relationships among species. Using the molecular clock, we can trace an infection back to transmission using HIV-1 sequences from a single time point. Whether or not a strict molecular clock applies to HIV-1's early evolution in the presence of immune selection has not yet been fully examined. We identified molecular clock signatures from 1587 previously published HIV-1 full envelope gene sequences obtained since acute infection in 15 subjects. Each subject's sequence diversity linearly increased during the first 150 days post infection, with rates ranging from [Formula: see text] to [Formula: see text] with a mean of [Formula: see text] per base per day. The rate of diversification for 12 out of the 15 subjects was comparable to the neutral evolution rate. While temporal diversification was consistent with evolution patterns in the absence of selection, mutations from the founder virus were highly clustered on statistically identified selection sites, which diversified more than 65 times faster than non-selection sites. By mathematically quantifying deviations from the molecular clock under various selection scenarios, we demonstrate that the deviation from a constant clock becomes negligible as multiple escape lineages emerge. The most recent common ancestor of a virus pair from distinct escape lineages is most likely the transmitted founder virus, indicating that HIV-1 molecular dating is feasible even after the founder viruses are no longer detectable. The ability of HIV-1 to escape from immune surveillance in many different directions is the driving force of molecular clock persistence. This finding advances our understanding of the robustness of HIV-1's molecular clock under immune selection, implying the potential for molecular dating.

  15. Modulation of Innate Immunity by Copolymer-1 Leads to Neuroprotection in Murine HIV-1 Encephalitis

    PubMed Central

    Gorantla, Santhi; Liu, Jianuo; Wang, Tong; Holguin, Adelina; Sneller, Hannah M; Dou, Huanyu; Kipnis, Jonathan; Poluektova, Larisa; Gendelman, Howard E

    2009-01-01

    Virus-infected and immune competent mononuclear phagocytes (MP; perivascular macrophages and microglia) drive the neuropathogenesis of human immunodeficiency virus type one (HIV-1) infection. Modulation of the MP phenotype from neurodestructive to neuroprotective underlies adjunctive therapeutic strategies for human disease. We reasoned that, as Copolymer-1 (Cop-1) can induce neuroprotective activities in a number of neuroinflammatory and neurodegenerative disorders, it could directly modulate HIV-1 infected MP neurotoxic activities. We now demonstrate that, in laboratory assays, Cop-1-stimulated virus-infected human monocyte-derived macrophages protect against neuronal injury and elicit anti-retroviral activities. Severe combined immune deficient (SCID) mice were stereotactically injected with HIV-1 infected human monocyte-derived macrophages, into the basal ganglia, to induce HIV-1 encephalitis (HIVE). Cop-1 was administered subcutaneously for 7 days. In HIVE mice Cop-1 treatment led to anti-inflammatory and neuroprotective responses. Reduced micro- and astro- gliosis, and conserved NeuN/MAP-2 levels were observed in virus affected brain regions in Cop-1-treated mice. These were linked to interleukin-10 and brain-derived neurotrophic factor expression and downregulation of inducible nitric oxide synthase. The data, taken together, demonstrate that Cop-1 can modulate innate immunity and, as such, improve disease outcomes in an animal model of HIVE. PMID:18046731

  16. Immune responses to the smallpox vaccine given in combination with ST-246, a small-molecule inhibitor of poxvirus dissemination.

    PubMed

    Grosenbach, Douglas W; Jordan, Robert; King, David S; Berhanu, Aklile; Warren, Travis K; Kirkwood-Watts, Dana L; Tyavanagimatt, Shanthakumar; Tan, Ying; Wilson, Rebecca L; Jones, Kevin F; Hruby, Dennis E

    2008-02-13

    The re-emerging threat of smallpox and the emerging threat of monkeypox highlight the need for effective poxvirus countermeasures. Currently approved smallpox vaccines have unacceptable safety profiles and, consequently, the general populace is no longer vaccinated, leading to an increasingly susceptible population. ST-246, a small-molecule inhibitor of poxvirus dissemination, has been demonstrated in various animal models to be safe and effective in preventing poxviral disease. This suggests that it may also be used to improve the safety of the traditional smallpox vaccine provided that it does not inhibit vaccine-induced protective immunity. In this study, we compared the immune responses elicited by the smallpox vaccine alone or in combination with ST-246 in mice. Normal lesion formation following dermal scarification with the attenuated New York City Board of Health strain (Dryvax), commonly referred to as a vaccine "take", was not inhibited although severe lesions and systemic disease due to vaccination with the virulent Western Reserve (VV-WR) strain were prevented. The vaccine given with ST-246 did not affect cellular immune responses or neutralizing antibody titers although anti-vaccinia ELISA titers were slightly reduced. Vaccination in combination with ST-246 provided equivalent short- and long-term protection against lethal intranasal challenge with VV-WR when compared to vaccine alone. These results suggest that ST-246 does not compromise protective immunity elicited by the vaccine and provide the basis for future studies examining the efficacy of ST-246 in preventing or treating adverse events due to vaccination.

  17. Population-Level Immune-Mediated Adaptation in HIV-1 Polymerase during the North American Epidemic.

    PubMed

    Kinloch, Natalie N; MacMillan, Daniel R; Le, Anh Q; Cotton, Laura A; Bangsberg, David R; Buchbinder, Susan; Carrington, Mary; Fuchs, Jonathan; Harrigan, P Richard; Koblin, Beryl; Kushel, Margot; Markowitz, Martin; Mayer, Kenneth; Milloy, M J; Schechter, Martin T; Wagner, Theresa; Walker, Bruce D; Carlson, Jonathan M; Poon, Art F Y; Brumme, Zabrina L

    2015-11-11

    Human leukocyte antigen (HLA) class I-associated polymorphisms in HIV-1 that persist upon transmission to HLA-mismatched hosts may spread in the population as the epidemic progresses. Transmission of HIV-1 sequences containing such adaptations may undermine cellular immune responses to the incoming virus in future hosts. Building upon previous work, we investigated the extent of HLA-associated polymorphism accumulation in HIV-1 polymerase (Pol) through comparative analysis of linked HIV-1/HLA class I genotypes sampled during historic (1979 to 1989; n = 338) and modern (2001 to 2011; n = 278) eras from across North America (Vancouver, BC, Canada; Boston, MA; New York, NY; and San Francisco, CA). Phylogenies inferred from historic and modern HIV-1 Pol sequences were star-like in shape, with an inferred most recent common ancestor (epidemic founder virus) sequence nearly identical to the modern North American subtype B consensus sequence. Nevertheless, modern HIV-1 Pol sequences exhibited roughly 2-fold-higher patristic (tip-to-tip) genetic distances than historic sequences, with HLA pressures likely driving ongoing diversification. Moreover, the frequencies of published HLA-associated polymorphisms in individuals lacking the selecting HLA class I allele was on average ∼2.5-fold higher in the modern than in the historic era, supporting their spread in circulation, though some remained stable in frequency during this time. Notably, polymorphisms restricted by protective HLA alleles appear to be spreading to a greater relative extent than others, though these increases are generally of modest absolute magnitude. However, despite evidence of polymorphism spread, North American hosts generally remain at relatively low risk of acquiring an HIV-1 polymerase sequence substantially preadapted to their HLA profiles, even in the present era. HLA class I-restricted cytotoxic T-lymphocyte (CTL) escape mutations in HIV-1 that persist upon transmission may accumulate in

  18. Humoral Immune Pressure Selects for HIV-1 CXC-chemokine Receptor 4-using Variants.

    PubMed

    Lin, Nina; Gonzalez, Oscar A; Registre, Ludy; Becerril, Carlos; Etemad, Behzad; Lu, Hong; Wu, Xueling; Lockman, Shahin; Essex, Myron; Moyo, Sikhulile; Kuritzkes, Daniel R; Sagar, Manish

    2016-06-01

    Although both C-C chemokine receptor 5 (CCR5)- and CXC chemokine receptor 4 (CXCR4)-using HIV-1 strains cause AIDS, the emergence of CXCR4-utilizing variants is associated with an accelerated decline in CD4+ T cells. It remains uncertain if CXCR4-using viruses hasten disease or if these variants only emerge after profound immunological damage. We show that exclusively CXCR4- as compared to cocirculating CCR5-utilizing variants are less sensitive to neutralization by both contemporaneous autologous plasma and plasma pools from individuals that harbor only CCR5-using HIV-1. The CXCR4-utilizing variants, however, do not have a global antigenic change because they remain equivalently susceptible to antibodies that do not target coreceptor binding domains. Studies with envelope V3 loop directed antibodies and chimeric envelopes suggest that the neutralization susceptibility differences are potentially influenced by the V3 loop. In vitro passage of a neutralization sensitive CCR5-using virus in the presence of autologous plasma and activated CD4+ T cells led to the emergence of a CXCR4-utilizing virus in 1 of 3 cases. These results suggest that in some but not necessarily all HIV-1 infected individuals humoral immune pressure against the autologous virus selects for CXCR4-using variants, which potentially accelerates disease progression. Our observations have implications for using antibodies for HIV-1 immune therapy.

  19. HIV-1 VACCINES. Diversion of HIV-1 vaccine-induced immunity by gp41-microbiota cross-reactive antibodies.

    PubMed

    Williams, Wilton B; Liao, Hua-Xin; Moody, M Anthony; Kepler, Thomas B; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly E; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, M Juliana; Mascola, John R; Koup, Richard A; Corey, Lawrence; Nabel, Gary J; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S; Baden, Lindsey R; Tomaras, Georgia D; Haynes, Barton F

    2015-08-14

    An HIV-1 DNA prime vaccine, with a recombinant adenovirus type 5 (rAd5) boost, failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than to gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells responded to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies were non-neutralizing and frequently polyreactive with host and environmental antigens, including intestinal microbiota (IM). Next-generation sequencing of an immunoglobulin heavy chain variable region repertoire before vaccination revealed an Env-IM cross-reactive Ab that was clonally related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy. Copyright © 2015, American Association for the Advancement of Science.

  20. Vaccines that stimulate T cell immunity to HIV-1: the next step.

    PubMed

    McMichael, Andrew J; Koff, Wayne C

    2014-04-01

    The search for a vaccine against human immunodeficiency virus type 1 (HIV-1) has many hurdles to overcome. Ideally, the stimulation of both broadly neutralizing antibodies and cell-mediated immune responses remains the best option, but no candidate in clinical trials at present has elicited such antibodies, and efficacy trials have not demonstrated any benefit for vaccines designed to stimulate immune responses of CD8(+) T cells. Findings obtained with the simian immunodeficiency virus (SIV) monkey model have provided new evidence that stimulating effective CD8(+) T cell immunity could provide protection, and in this Perspective we explore the path forward for optimizing such responses in humans.

  1. Targeting HIV-1 Env gp140 to LOX-1 Elicits Immune Responses in Rhesus Macaques.

    PubMed

    Zurawski, Gerard; Zurawski, Sandra; Flamar, Anne-Laure; Richert, Laura; Wagner, Ralf; Tomaras, Georgia D; Montefiori, David C; Roederer, Mario; Ferrari, Guido; Lacabaratz, Christine; Bonnabau, Henri; Klucar, Peter; Wang, Zhiqing; Foulds, Kathryn E; Kao, Shing-Fen; Yates, Nicole L; LaBranche, Celia; Jacobs, Bertram L; Kibler, Karen; Asbach, Benedikt; Kliche, Alexander; Salazar, Andres; Reed, Steve; Self, Steve; Gottardo, Raphael; Galmin, Lindsey; Weiss, Deborah; Cristillo, Anthony; Thiebaut, Rodolphe; Pantaleo, Giuseppe; Levy, Yves

    2016-01-01

    Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1.

  2. Targeting HIV-1 Env gp140 to LOX-1 Elicits Immune Responses in Rhesus Macaques

    PubMed Central

    Zurawski, Sandra; Flamar, Anne-Laure; Richert, Laura; Wagner, Ralf; Tomaras, Georgia D.; Montefiori, David C.; Roederer, Mario; Ferrari, Guido; Lacabaratz, Christine; Bonnabau, Henri; Klucar, Peter; Wang, Zhiqing; Foulds, Kathryn E.; Kao, Shing-Fen; Yates, Nicole L.; LaBranche, Celia; Jacobs, Bertram L.; Kibler, Karen; Asbach, Benedikt; Kliche, Alexander; Salazar, Andres; Reed, Steve; Self, Steve; Gottardo, Raphael; Galmin, Lindsey; Weiss, Deborah; Cristillo, Anthony; Thiebaut, Rodolphe; Pantaleo, Giuseppe; Levy, Yves

    2016-01-01

    Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1. PMID:27077384

  3. HIV-1 Negative Female Sex Workers Sustain High Cervical IFNε, Low Immune Activation and Low Expression of HIV-1 Required Host Genes

    PubMed Central

    Abdulhaqq, Shaheed A.; Zorrilla, Carmen; Kang, Guobin; Yin, Xiangfan; Tamayo, Vivian; Seaton, Kelly E.; Joseph, Jocelin; Garced, Sheyla; Tomaras, Georgia D.; Linn, Kristin A.; Foulkes, Andrea S.; Azzoni, Livio; VerMilyea, Matthew; Coutifaris, Christos; Kossenkov, Andrew V.; Showe, Louise; Kraiselburd, Edmundo N.; Li, Qingsheng; Montaner, Luis J.

    2015-01-01

    Sex workers within high HIV endemic areas are often a target population where anti-HIV prophylactic strategies are tested. We hypothesize that in women with high levels of genital exposure to semen changes in cervicovaginal mucosal and/or systemic immune activation will contribute to a decreased susceptibility to HIV-1 infection. To address this question, we assessed sexual activity, immune activation status (in peripheral blood), as well as cellular infiltrates and gene expression in ectocervical mucosa biopsies in female sex workers [FSW] (n=50), as compared to control women [CG] (n=32). FSW had low to absent HIV-1 specific immune responses with significantly lower CD38 expression on circulating CD4+ or CD8+ T-Cells (both: p<0.001) together with lower cervical gene expression of genes associated with leukocyte homing and chemotaxis. FSW also had increased levels of Interferon-ε gene and protein expression in the cervical epithelium together with reduced expression of genes associated with HIV-1 integration and replication. A correlative relationship between semen exposure and elevated type-1 IFN expression in FSW was also established. Overall, our data suggest that long-term condomless sex work can result in multiple changes within the cervicovaginal compartment that would contribute to sustaining a lower susceptibility for HIV-1 infection in absence of HIV-specific responses. PMID:26555708

  4. The Effect of Chloroquine on Immune Activation and Interferon Signatures Associated with HIV-1

    PubMed Central

    Bosinger, Steven E.; Kang, Minhee; Belaunzaran-Zamudio, Pablo; Matining, Roy M.; Wilson, Cara C.; Flexner, Charles; Clagett, Brian; Plants, Jill; Read, Sarah; Purdue, Lynette; Myers, Laurie; Boone, Linda; Tebas, Pablo; Kumar, Princy; Clifford, David; Douek, Daniel; Silvestri, Guido; Landay, Alan L.; Lederman, Michael M.

    2016-01-01

    Abstract Immune activation associated with HIV-1 infection contributes to morbidity and mortality. We studied whether chloroquine, through Toll-like receptor (TLR) antagonist properties, could reduce immune activation thought to be driven by TLR ligands, such as gut-derived bacterial elements and HIV-1 RNAs. AIDS Clinical Trials Group A5258 was a randomized, double-blind, placebo-controlled study in 33 HIV-1-infected participants off antiretroviral therapy (ART) and 37 participants on ART. Study participants in each cohort were randomized 1:1 to receive chloroquine 250 mg orally for the first 12 weeks then cross over to placebo for 12 weeks or placebo first and then chloroquine. Combining the periods of chloroquine use in both arms of the on-ART cohort yielded a modest reduction in the proportions of CD8 T cells co-expressing CD38 and DR (median decrease = 3.0%, p = .003). The effect on immune activation in the off-ART cohort was likely confounded by increased plasma HIV-1 RNA during chloroquine administration (median 0.29 log10 increase, p < .001). Transcriptional analyses in the off-ART cohort showed decreased expression of interferon-stimulated genes in 5 of 10 chloroquine-treated participants and modest decreases in CD38 and CCR5 RNAs in all chloroquine-treated participants. Chloroquine modestly reduced immune activation in ART-treated HIV-infected participants. Clinical Trials Registry Number: NCT00819390. PMID:26935044

  5. Autoimmune anti-HIV-1gp120 antibody with antiidiotype-like activity in sera and immune complexes of HIV-1-related immunologic thrombocytopenia.

    PubMed Central

    Karpatkin, S; Nardi, M

    1992-01-01

    Autoimmune antiidiotype-like antibody (Ab2) directed against anti-HIV-1gp120 (Ab1) was found in high titer in the sera of 10 consecutive homosexual and 11 narcotic addict HIV-1-related immunologic thrombocytopenia (HIV-1-ITP) patients, was barely detectable in 10 nonthrombocytopenic HIV-1 sero-positive individuals, and was not detectable in 5 normal subjects by use of a solid-phase RIA. Reactivity of autologous Ab2 for Ab1 was 4-120-fold greater than Ab2 for homologous Ab1. Affinity-purified Ab2 did not block the binding of affinity-purified Ab1 to its HIV-1gp120 epitopes on immunoblot, indicating the absence of "internal image" antiidiotype. Both Ab1 and Ab2 are precipitable from sera with polyethylene glycol (PEG) and present in a macromolecular complex that is excluded by gel filtration on G200 and contains IgG, IgM, C3, and the anti-F(ab')2 antiidiotype-like complex. PEG-precipitable complexes bind to platelets in a saturation-dependent manner. Neither affinity-purified Ab1 nor Ab2 binds to platelets. However, the combination of Ab1 and Ab2 (preincubated for 2 h at 22 degrees C) binds to platelets in a saturation-dependent manner at an optimum ratio range of 10-20:1. Ab2 reactivity correlates with serum PEG-precipitable immune complex level (r = 0.91; P less than 0.001) and with thrombocytopenia (r = 0.89; P less than 0.001). We suggest that the anti-HIV-1gp120 antiidiotype-like complex contributes to the markedly elevated platelet Ig and C3 level of HIV-1-ITP patients and propose that this may contribute to their thrombocytopenia. Images PMID:1737832

  6. Genetic determinants of HIV-1 infection and progression to AIDS: immune response genes.

    PubMed

    Kaur, G; Mehra, N

    2009-11-01

    Genomic studies involving well-defined multicenter cohorts of HIV-1/AIDS covering multiple populations have led to a greater understanding of the role of host determinants in viral acquisition, disease progression, transmission, and response to anti-retroviral therapy. Similarly, recent knowledge on the virus genetic diversity has helped in elucidating mechanisms leading to the evolution of viral escape mutants and the role played by host immune determinants, in particular the major histocompatibility complex (MHC) associated genes. At least two alleles, HLA-B*27 and B*57, have been identified as 'protective' against HIV-1 while B*35 and B*53 act as susceptibility favoring factors. How human leukocyte antigen (HLA)-mediated selection drives the evolution of HIV-1 and which circulating variants are more likely to evade immune surveillance of the population are now beginning to become clear. Importantly, the rare HLA alleles in a population bear a selective advantage to the host because these can induce immune responses against pre-adapted viruses. It is conceivable that previously established protective HLA associations are shifting with the evolving cytotoxic T lymphocyte (CTL) epitopes and may not remain protective in future. At the same time, this process is unraveling novel sub-dominant epitopes of the virus which could now be incorporated as the dominant target CTL epitopes. An insight into the population-specific correlates of protection is hence necessary for designing future anti-HIV therapeutic and/or prophylactic vaccine formulation(s).

  7. Prime/boost immunization with HIV-1 MPER-V3 fusion construct enhances humoral and cellular immune responses.

    PubMed

    Bolhassani, Azam; Kardani, Kimia; Vahabpour, Rouhollah; Habibzadeh, Nourieh; Aghasadeghi, Mohammad Reza; Sadat, Seyed Mehdi; Agi, Elnaz

    2015-12-01

    Development of an effective vaccine against HIV-1 infection is a main concern in worldwide. A potent vaccine for HIV-1 requires the induction and maintenance of both humoral and cellular immunity. In this study, the levels of humoral and cellular immune responses were compared using MPER-V3 injection in three immunization strategies such as DNA/DNA, peptide/peptide, and DNA/peptide (prime-boost). MPG peptide and Montanide 720 were used as a DNA delivery system, and as a peptide adjuvant, respectively. Our results demonstrated that MPG forms stable non-covalent nanoparticles with plasmid DNA at N/P ratio of 10:1 (∼ 110-130 nm). The in vitro transfection efficiency of MPER-V3 DNA using MPG was comparable with lipofectamine and turbofect reagents as a common delivery system. In vivo prime-boost immunization using HIV-1 MPER-V3 could significantly enhance humoral and cellular immune responses as compared to control groups. The mixture of IgG1 and IgG2a was observed for each strategy, but IFN-γ production was significantly higher in prime-boost and peptide immunizations than that in DNA immunizations, inducing Th1 response. Moreover, our data showed that prime immunization with low dose of the nanoparticles (MPER-V3 DNA: MPG at ratio of 1:10) followed by MPER-V3 peptide drives T cell responses towards a Th1-type similar to high dose of the naked DNA prime/peptide boost immunization. Generally, the prime-boost strategy could improve both immune responses against MPER and especially V3 peptides suggesting its application as a promising HIV vaccine candidate in future. Copyright © 2015 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  8. The innate immune response to HIV-1: to sense or not to sense.

    PubMed

    Landau, Nathaniel R

    2014-05-01

    The immune responses to viruses provide a means to quickly alert the host to the presence of an invader, activating a range of intrinsic and adaptive antiviral mechanisms. Several research groups have made advances in understanding the innate immune response to HIV-1, although their findings differ. Some investigators find that the virus slips under the radar of the pattern recognition receptors that sense viruses by co-opting host factors that restrict accessibility of the viral nucleic acids, while others find that the virus is sensed and activates a type-I interferon response. This article reviews the recent findings and discusses the similarities and differences.

  9. The Innate Immune Response to HIV-1: To Sense or Not to Sense

    PubMed Central

    2014-01-01

    The immune responses to viruses provide a means to quickly alert the host to the presence of an invader, activating a range of intrinsic and adaptive antiviral mechanisms. Several research groups have made advances in understanding the innate immune response to HIV-1, although their findings differ. Some investigators find that the virus slips under the radar of the pattern recognition receptors that sense viruses by co-opting host factors that restrict accessibility of the viral nucleic acids, while others find that the virus is sensed and activates a type-I interferon response. This article reviews the recent findings and discusses the similarities and differences. PMID:24665823

  10. HIV-1 Tat modulates T-bet expression and induces Th1 type of immune response

    SciTech Connect

    Kulkarni, Asavari; Ravi, Dyavar S.; Singh, Kamini; Rampalli, Shravanti; Parekh, Vrajesh; Mitra, Debashis; Chattopadhyay, Samit . E-mail: samit@nccs.res.in

    2005-04-08

    The HIV-1 transactivator Tat performs various viral and cellular functions. Primarily, it induces processive transcription from the HIV-1 LTR promoter. However, Tat secreted from infected cells is known to activate uninfected lymphocytes through receptors. To further delineate the specific target genes, extracellular Tat was expressed on the cell membrane of stimulator cells and co-cultured with human PBMCs. Along with induced CD4{sup +} T cell proliferation and IFN-{gamma} secretion, there was strong upregulation of T-bet expression which is majorly implicated in generating T{sub H}1 type of immune response. To further delineate the effect of extracellular Tat on HIV replication, both p24 analysis and in vivo GFP expression were performed. There was a significant inhibition of HIV-1 replication in human CEM-GFP cell line and hPBMCs. Thus, for the first time we report that apart from its transactivation activity, extracellular Tat acts as a costimulatory molecule that affects viral replication by modulating host immune response through induction of T-bet expression and IFN-{gamma} secretion.

  11. Caps off to poxviruses.

    PubMed

    Silverman, Robert H

    2015-03-11

    In this issue of Cell Host & Microbe, Liu et al. (2015) and Burgess and Mohr (2015) describe how two poxvirus mRNA decapping enzymes hijack a host 5'-to-3'-exoribonuclease to evade antiviral innate immunity by limiting accumulation of double-stranded RNA.

  12. Immune responses to the smallpox vaccine given in combination with ST-246, a small-molecule inhibitor of poxvirus dissemination

    PubMed Central

    Grosenbach, Douglas W.; Jordan, Robert; King, David S.; Berhanu, Aklile; Warren, Travis K.; Kirkwood-Watts, Dana L.; Tyavanagimatt, Shanthakumar; Tan, Ying; Wilson, Rebecca L.; Jones, Kevin F.; Hruby, Dennis E.

    2009-01-01

    Summary The re-emerging threat of smallpox and the emerging threat of monkeypox highlight the need for effective poxvirus countermeasures. Currently approved smallpox vaccines have unacceptable safety profiles and, consequently, the general populace is no longer vaccinated, leading to an increasingly susceptible population. ST-246, a small-molecule inhibitor of poxvirus dissemination, has been demonstrated in various animal models to be safe and effective in preventing poxviral disease. This suggests that it may also be used to improve the safety of the traditional smallpox vaccine provided that it does not inhibit vaccine-induced protective immunity. In this study, we compared the immune responses elicited by the smallpox vaccine alone or in combination with ST-246 in mice. Normal lesion formation following dermal scarification with the attenuated New York City Board of Health strain (Dryvax), commonly referred to as a vaccine “take”, was not inhibited although severe lesions and systemic disease due to vaccination with the virulent Western Reserve (VV-WR) strain were prevented. The vaccine given with ST-246 did not affect cellular immune responses or neutralizing antibody titers although anti-vaccinia ELISA titers were slightly reduced. Vaccination in combination with ST-246 provided equivalent short- and long-term protection against lethal intranasal challenge with VV-WR when compared to vaccine alone. These results suggest that ST-246 does not compromise protective immunity elicited by the vaccine and provide the basis for future studies examining the efficacy of ST-246 in preventing or treating adverse events due to vaccination. PMID:18226434

  13. HIV-1 replication in human immune cells is independent of TAR DNA binding protein 43 (TDP-43) expression.

    PubMed

    Nehls, Julia; Koppensteiner, Herwig; Brack-Werner, Ruth; Floss, Thomas; Schindler, Michael

    2014-01-01

    The TAR DNA binding protein (TDP-43) was originally identified as a host cell factor binding to the HIV-1 LTR and thereby suppressing HIV-1 transcription and gene expression (Ou et al., J.Virol. 1995, 69(6):3584). TDP-43 is a global regulator of transcription, can influence RNA metabolism in many different ways and is ubiquitously expressed. Thus, TDP-43 could be a major factor restricting HIV-1 replication at the level of LTR transcription and gene expression. These facts prompted us to revisit the role of TDP-43 for HIV-1 replication. We utilized established HIV-1 cell culture systems as well as primary cell models and performed a comprehensive analysis of TDP-43 function and investigated its putative impact on HIV-1 gene expression. In HIV-1 infected cells TDP-43 was neither degraded nor sequestered from the nucleus. Furthermore, TDP-43 overexpression as well as siRNA mediated knockdown did not affect HIV-1 gene expression and virus production in T cells and macrophages. In summary, our experiments argue against a restricting role of TDP-43 during HIV-1 replication in immune cells.

  14. HIV-1 Replication in Human Immune Cells Is Independent of TAR DNA Binding Protein 43 (TDP-43) Expression

    PubMed Central

    Nehls, Julia; Koppensteiner, Herwig; Brack-Werner, Ruth; Floss, Thomas; Schindler, Michael

    2014-01-01

    The TAR DNA binding protein (TDP-43) was originally identified as a host cell factor binding to the HIV-1 LTR and thereby suppressing HIV-1 transcription and gene expression (Ou et al., J.Virol. 1995, 69(6):3584). TDP-43 is a global regulator of transcription, can influence RNA metabolism in many different ways and is ubiquitously expressed. Thus, TDP-43 could be a major factor restricting HIV-1 replication at the level of LTR transcription and gene expression. These facts prompted us to revisit the role of TDP-43 for HIV-1 replication. We utilized established HIV-1 cell culture systems as well as primary cell models and performed a comprehensive analysis of TDP-43 function and investigated its putative impact on HIV-1 gene expression. In HIV-1 infected cells TDP-43 was neither degraded nor sequestered from the nucleus. Furthermore, TDP-43 overexpression as well as siRNA mediated knockdown did not affect HIV-1 gene expression and virus production in T cells and macrophages. In summary, our experiments argue against a restricting role of TDP-43 during HIV-1 replication in immune cells. PMID:25127017

  15. Differential immune mechanism to HIV-1 Tat variants and its regulation by AEA [corrected].

    PubMed

    Krishnan, Gopinath; Chatterjee, Nivedita

    2015-05-06

    In the retina, Müller glia is a dominant player of immune response. The HIV-1 transactivator viral protein (Tat) induces production of several neurotoxic cytokines in retinal cells. We show that HIV-1 clades Tat B and C act differentially on Müller glia, which is reflected in apoptosis, activation of cell death pathway components and pro-inflammatory cytokines. The harsher immune-mediated pathology of Tat B, as opposed to milder effects of Tat C, manifests at several signal transduction pathways, notably, MAPK, STAT, SOCS, the NFκB signalosome, and TTP. In activated cells, anandamide (AEA), acting as an immune-modulator, suppresses Tat B effect through MKP-1 but Tat C action via MEK-1. AEA lowers nuclear NF-κB and TAB2 for both variants while elevating IRAK1BP1 in activated Müller glia. Müller glia exposed to Tat shows enhanced PBMC attachment. Tat-induced increase in leukocyte adhesion to Müller cells can be mitigated by AEA, involving both CB receptors. This study identifies multiple signalling components that drive immune-mediated pathology and contribute to disease severity in HIV clades. We show that the protective effects of AEA occur at various stages in cytokine generation and are clade-dependant.

  16. Sequential Immunization Elicits Broadly Neutralizing Anti-HIV-1 Antibodies in Ig Knockin Mice.

    PubMed

    Escolano, Amelia; Steichen, Jon M; Dosenovic, Pia; Kulp, Daniel W; Golijanin, Jovana; Sok, Devin; Freund, Natalia T; Gitlin, Alexander D; Oliveira, Thiago; Araki, Tatsuya; Lowe, Sarina; Chen, Spencer T; Heinemann, Jennifer; Yao, Kai-Hui; Georgeson, Erik; Saye-Francisco, Karen L; Gazumyan, Anna; Adachi, Yumiko; Kubitz, Michael; Burton, Dennis R; Schief, William R; Nussenzweig, Michel C

    2016-09-08

    A vaccine that elicits broadly neutralizing antibodies (bNAbs) against HIV-1 is likely to be protective, but this has not been achieved. To explore immunization regimens that might elicit bNAbs, we produced and immunized mice expressing the predicted germline PGT121, a bNAb specific for the V3-loop and surrounding glycans on the HIV-1 spike. Priming with an epitope-modified immunogen designed to activate germline antibody-expressing B cells, followed by ELISA-guided boosting with a sequence of directional immunogens, native-like trimers with decreasing epitope modification, elicited heterologous tier-2-neutralizing responses. In contrast, repeated immunization with the priming immunogen did not. Antibody cloning confirmed elicitation of high levels of somatic mutation and tier-2-neutralizing antibodies resembling the authentic human bNAb. Our data establish that sequential immunization with specifically designed immunogens can induce high levels of somatic mutation and shepherd antibody maturation to produce bNAbs from their inferred germline precursors.

  17. A poxvirus Bcl-2-like gene family involved in regulation of host immune response: sequence similarity and evolutionary history

    PubMed Central

    2010-01-01

    Background Poxviruses evade the immune system of the host through the action of viral encoded inhibitors that block various signalling pathways. The exact number of viral inhibitors is not yet known. Several members of the vaccinia virus A46 and N1 families, with a Bcl-2-like structure, are involved in the regulation of the host innate immune response where they act non-redundantly at different levels of the Toll-like receptor signalling pathway. N1 also maintains an anti-apoptotic effect by acting similarly to cellular Bcl-2 proteins. Whether there are related families that could have similar functions is the main subject of this investigation. Results We describe the sequence similarity existing among poxvirus A46, N1, N2 and C1 protein families, which share a common domain of approximately 110-140 amino acids at their C-termini that spans the entire N1 sequence. Secondary structure and fold recognition predictions suggest that this domain presents an all-alpha-helical fold compatible with the Bcl-2-like structures of vaccinia virus proteins N1, A52, B15 and K7. We propose that these protein families should be merged into a single one. We describe the phylogenetic distribution of this family and reconstruct its evolutionary history, which indicates an extensive gene gain in ancestral viruses and a further stabilization of its gene content. Conclusions Based on the sequence/structure similarity, we propose that other members with unknown function, like vaccinia virus N2, C1, C6 and C16/B22, might have a similar role in the suppression of host immune response as A46, A52, B15 and K7, by antagonizing at different levels with the TLR signalling pathways. PMID:20230632

  18. HIV-1 and hijacking of the host immune system: the current scenario.

    PubMed

    Imran, Muhammad; Manzoor, Sobia; Saalim, Muhammad; Resham, Saleha; Ashraf, Javed; Javed, Aneela; Waqar, Ahmed Bilal

    2016-10-01

    Human immunodeficiency virus (HIV) infection is a major health burden across the world which leads to the development of acquired immune deficiency syndrome (AIDS). This review article discusses the prevalence of HIV, its major routes of transmission, natural immunity, and evasion from the host immune system. HIV is mostly prevalent in Sub-Saharan Africa and low income countries. It is mostly transmitted by sharing syringe needles, blood transfusion, and sexual routes. The host immune system is categorized into three main types; the innate, the adaptive, and the intrinsic immune system. Regarding the innate immune system against HIV, the key players are mucosal membrane, dendritic cells (DCs), complement system, interferon, and host Micro RNAs. The major components of the adaptive immune system exploited by HIV are T cells mainly CD4+ T cells and B cells. The intrinsic immune system confronted by HIV involves (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G) APOBEC3G, tripartite motif 5-α (TRIM5a), terherin, and (SAM-domain HD-domain containing protein) SAMHD1. HIV-1 efficiently interacts with the host immune system, exploits the host machinery, successfully replicates and transmits from one cell to another. Further research is required to explore evasion strategies of HIV to develop novel therapeutic approaches against HIV.

  19. Diverse antibody genetic and recognition properties revealed following HIV-1 Env immunization

    PubMed Central

    Phad, Ganesh E.; Bernat, Néstor Vázquez; Feng, Yu; Ingale, Jidnyasa; Murillo, Paola Andrea Martinez; O’Dell, Sijy; Li, Yuxing; Mascola, John R.; Sundling, Christopher; Wyatt, Richard T.; Karlsson Hedestam, Gunilla B.

    2015-01-01

    Isolation of monoclonal antibodies (MAbs) elicited by vaccination provides opportunities to define the development of effective immunity. Ab responses elicited by current HIV-1 envelope glycoprotein (Env) immunogens display narrow neutralizing activity with limited capacity to block infection by tier 2 viruses. Intense work in the field suggests that improved Env immunogens are forthcoming and it is therefore important to concurrently develop approaches to investigate the quality of vaccine-elicited responses at a higher level of resolution. Here, we cloned a representative set of MAbs elicited by a model Env immunogen in rhesus macaques and comprehensively characterized their genetic and functional properties. The MAbs were genetically diverse, even within groups of Abs targeting the same sub-region of Env, consistent with a highly polyclonal response. MAbs directed against two sub-determinants of Env, the CD4 binding site (CD4bs) and the V3 region, could in part account for the neutralizing activity observed in the plasma of the animal from which they were cloned, demonstrating the power of MAb isolation for a detailed understanding of the elicited response. Finally, through comparative analyses of MAb binding and neutralizing capacity of HIV-1 using matched Envs, we demonstrate complex relationships between epitope recognition and accessibility, highlighting the protective quaternary packing of the HIV-1 spike relative to vaccine-induced MAbs. PMID:25964491

  20. A Mechanistic Understanding of Allosteric Immune Escape Pathways in the HIV-1 Envelope Glycoprotein

    PubMed Central

    Sethi, Anurag; Tian, Jianhui; Derdeyn, Cynthia A.; Korber, Bette; Gnanakaran, S.

    2013-01-01

    The HIV-1 envelope (Env) spike, which consists of a compact, heterodimeric trimer of the glycoproteins gp120 and gp41, is the target of neutralizing antibodies. However, the high mutation rate of HIV-1 and plasticity of Env facilitates viral evasion from neutralizing antibodies through various mechanisms. Mutations that are distant from the antibody binding site can lead to escape, probably by changing the conformation or dynamics of Env; however, these changes are difficult to identify and define mechanistically. Here we describe a network analysis-based approach to identify potential allosteric immune evasion mechanisms using three known HIV-1 Env gp120 protein structures from two different clades, B and C. First, correlation and principal component analyses of molecular dynamics (MD) simulations identified a high degree of long-distance coupled motions that exist between functionally distant regions within the intrinsic dynamics of the gp120 core, supporting the presence of long-distance communication in the protein. Then, by integrating MD simulations with network theory, we identified the optimal and suboptimal communication pathways and modules within the gp120 core. The results unveil both strain-dependent and -independent characteristics of the communication pathways in gp120. We show that within the context of three structurally homologous gp120 cores, the optimal pathway for communication is sequence sensitive, i.e. a suboptimal pathway in one strain becomes the optimal pathway in another strain. Yet the identification of conserved elements within these communication pathways, termed inter-modular hotspots, could present a new opportunity for immunogen design, as this could be an additional mechanism that HIV-1 uses to shield vulnerable antibody targets in Env that induce neutralizing antibody breadth. PMID:23696718

  1. "In vitro systems to characterize the immune response to HIV-1 and HIV-1 vaccine candidates", NIAID Workshop Report, Bethesda, August 4, 2010.

    PubMed

    Malaspina, Angela; Rinaldo, Charles R; Sekaly, Rafick P; Flores, Jorge; D'Souza, Patricia M

    2011-06-24

    Although clinical trials are the ultimate way to prove vaccine safety and efficacy, the complexity, cost and time required to develop a product to enter human trials demand a serious, long-term investment. Lack of knowledge on immune correlates of protection from HIV infections makes investments in HIV vaccine research significantly risky. Preclinical testing of HIV vaccines is routinely carried out in non-human primate models however these studies have a significant cost and their predictive value is still questionable. The potential value of screening new HIV-1 vaccine candidates on human cells and tissues via high throughput in vitro systems that allow rapid, cost-effective and accurate predictions of in vivo immune responses would be enormous. A one-day workshop was convened by Division of AIDS, National Institutes of Health on August 4, 2010 to address the benefits and challenges of assessing HIV-1 vaccine responses in alternative ways. Consideration was given to the use of various in vitro model systems, human mucosal tissue explants and humanized mouse models as ways to predict immunogenicity and efficacy of HIV-1 vaccines early in the development process, and support decisions on whether a product may be worthy of moving into non-human primates or human trials. This report summarizes the outcome of the workshop.

  2. Counteraction of HLA-C-Mediated Immune Control of HIV-1 by Nef▿ †

    PubMed Central

    Specht, Anke; Telenti, Amalio; Martinez, Raquel; Fellay, Jacques; Bailes, Elizabeth; Evans, David T.; Carrington, Mary; Hahn, Beatrice H.; Goldstein, David B.; Kirchhoff, Frank

    2010-01-01

    A host genetic variant (−35C/T) correlates with increased human leukocyte antigen C (HLA-C) expression and improved control of HIV-1. HLA-C-mediated immunity may be particularly protective because HIV-1 is unable to remove HLA-C from the cell surface, whereas it can avoid HLA-A- and HLA-B-mediated immunity by Nef-mediated down-modulation. However, some individuals with the protective −35CC genotype exhibit high viral loads. Here, we investigated whether the ability of HIV-1 to replicate efficiently in the “protective” high-HLA-C-expression host environment correlates with specific functional properties of Nef. We found that high set point viral loads (sVLs) were not associated with the emergence of Nef variants that had acquired the ability to down-modulate HLA-C or were more effective in removing HLA-A and HLA-B from the cell surface. However, in individuals with the protective −35CC genotype we found a significant association between sVLs and the efficiency of Nef-mediated enhancement of virion infectivity and modulation of CD4, CD28, and the major histocompatibility complex class II (MHC-II)-associated invariant chain (Ii), while this was not observed in subjects with the −35TT genotype. Since the latter Nef functions all influence the stimulation of CD4+ T helper cells by antigen-presenting cells, they may cooperate to affect both the activation status of infected T cells and the generation of an antiviral cytotoxic T-lymphocyte (CTL) response. In comparison, different levels of viremia in individuals with the common −35TT genotype were not associated with differences in Nef function but with differences in HLA-C mRNA expression levels. Thus, while high HLA-C expression may generally facilitate control of HIV-1, Nef may counteract HLA-C-mediated immune control in some individuals indirectly, by manipulating T-cell function and MHC-II antigen presentation. PMID:20463068

  3. Uncommon Pathways of Immune Escape Attenuate HIV-1 Integrase Replication Capacity

    PubMed Central

    Chopera, Denis R.; Olvera, Alex; Brumme, Chanson J.; Sela, Jennifer; Markle, Tristan J.; Martin, Eric; Carlson, Jonathan M.; Le, Anh Q.; McGovern, Rachel; Cheung, Peter K.; Kelleher, Anthony D.; Jessen, Heiko; Markowitz, Martin; Rosenberg, Eric; Frahm, Nicole; Sanchez, Jorge; Mallal, Simon; John, Mina; Harrigan, P. Richard; Heckerman, David; Brander, Christian; Walker, Bruce D.; Brumme, Zabrina L.

    2012-01-01

    An attenuation of the HIV-1 replication capacity (RC) has been observed for immune-mediated escape mutations in Gag restricted by protective HLA alleles. However, the extent to which escape mutations affect other viral proteins during natural infection is not well understood. We generated recombinant viruses encoding plasma HIV-1 RNA integrase sequences from antiretroviral-naïve individuals with early (n = 88) and chronic (n = 304) infections and measured the in vitro RC of each. In contrast to data from previous studies of Gag, we observed little evidence that host HLA allele expression was associated with integrase RC. A modest negative correlation was observed between the number of HLA-B-associated integrase polymorphisms and RC in chronic infection (R = −0.2; P = 0.003); however, this effect was not driven by mutations restricted by protective HLA alleles. Notably, the integrase variants S119R, G163E, and I220L, which represent uncommon polymorphisms associated with HLA-C*05, -A*33, and -B*52, respectively, correlated with lower RC (all q < 0.2). We identified a novel C*05-restricted epitope (HTDNGSNF114–121) that likely contributes to the selection of the S119R variant, the polymorphism most significantly associated with lower RC in patient sequences. An NL4-3 mutant encoding the S119R polymorphism displayed a ∼35%-reduced function that was rescued by a single compensatory mutation of A91E. Together, these data indicate that substantial HLA-driven attenuation of integrase is not a general phenomenon during HIV-1 adaptation to host immunity. However, uncommon polymorphisms selected by HLA alleles that are not conventionally regarded to be protective may be associated with impaired protein function. Vulnerable epitopes in integrase might therefore be considered for future vaccine strategies. PMID:22496233

  4. Dynamics of an HIV-1 infection model with cell mediated immunity

    NASA Astrophysics Data System (ADS)

    Yu, Pei; Huang, Jianing; Jiang, Jiao

    2014-10-01

    In this paper, we study the dynamics of an improved mathematical model on HIV-1 virus with cell mediated immunity. This new 5-dimensional model is based on the combination of a basic 3-dimensional HIV-1 model and a 4-dimensional immunity response model, which more realistically describes dynamics between the uninfected cells, infected cells, virus, the CTL response cells and CTL effector cells. Our 5-dimensional model may be reduced to the 4-dimensional model by applying a quasi-steady state assumption on the variable of virus. However, it is shown in this paper that virus is necessary to be involved in the modeling, and that a quasi-steady state assumption should be applied carefully, which may miss some important dynamical behavior of the system. Detailed bifurcation analysis is given to show that the system has three equilibrium solutions, namely the infection-free equilibrium, the infectious equilibrium without CTL, and the infectious equilibrium with CTL, and a series of bifurcations including two transcritical bifurcations and one or two possible Hopf bifurcations occur from these three equilibria as the basic reproduction number is varied. The mathematical methods applied in this paper include characteristic equations, Routh-Hurwitz condition, fluctuation lemma, Lyapunov function and computation of normal forms. Numerical simulation is also presented to demonstrate the applicability of the theoretical predictions.

  5. Cryptococcal immune reconstitution inflammatory syndrome in HIV-1-infected individuals: proposed clinical case definitions.

    PubMed

    Haddow, Lewis J; Colebunders, Robert; Meintjes, Graeme; Lawn, Stephen D; Elliott, Julian H; Manabe, Yukari C; Bohjanen, Paul R; Sungkanuparph, Somnuek; Easterbrook, Philippa J; French, Martyn A; Boulware, David R

    2010-11-01

    Cryptococcal immune reconstitution inflammatory syndrome (IRIS) may present as a clinical worsening or new presentation of cryptococcal disease after initiation of antiretroviral therapy (ART), and is thought to be caused by recovery of cryptococcus-specific immune responses. We have reviewed reports of cryptococcal IRIS and have developed a consensus case definition specifically for paradoxical crytopcoccal IRIS in patients with HIV-1 and known cryptococcal disease before ART, and a separate definition for incident cryptococcosis developed during ART (termed ART-associated cryptococcosis), for which a proportion of cases are likely to be unmasking cryptococcal IRIS. These structured case definitions are intended to aid design of future clinical, epidemiological, and immunopathological studies of cryptococcal IRIS, to standardise diagnostic criteria, and to facilitate comparisons between studies. As for definitions of tuberculosis-associated IRIS, definitions for cryptococcal IRIS should be regarded as preliminary until further insights into the immunopathology of IRIS permit their refinement.

  6. Poxvirus-Based Active Immunotherapy with PD-1 and LAG-3 Dual Immune Checkpoint Inhibition Overcomes Compensatory Immune Regulation, Yielding Complete Tumor Regression in Mice

    PubMed Central

    dela Cruz, Tracy; Cote, Joseph J.; Gordon, Evan J.; Kemp, Felicia; Xavier, Veronica; Franzusoff, Alex; Rountree, Ryan B.; Mandl, Stefanie J.

    2016-01-01

    Poxvirus-based active immunotherapies mediate anti-tumor efficacy by triggering broad and durable Th1 dominated T cell responses against the tumor. While monotherapy significantly delays tumor growth, it often does not lead to complete tumor regression. It was hypothesized that the induced robust infiltration of IFNγ-producing T cells into the tumor could provoke an adaptive immune evasive response by the tumor through the upregulation of PD-L1 expression. In therapeutic CT26-HER-2 tumor models, MVA-BN-HER2 poxvirus immunotherapy resulted in significant tumor growth delay accompanied by a robust, tumor-infiltrating T cell response that was characterized by low to mid-levels of PD-1 expression on T cells. As hypothesized, this response was countered by significantly increased PD-L1 expression on the tumor and, unexpectedly, also on infiltrating T cells. Synergistic benefit of anti-tumor therapy was observed when MVA-BN-HER2 immunotherapy was combined with PD-1 immune checkpoint blockade. Interestingly, PD-1 blockade stimulated a second immune checkpoint molecule, LAG-3, to be expressed on T cells. Combining MVA-BN-HER2 immunotherapy with dual PD-1 plus LAG-3 blockade resulted in comprehensive tumor regression in all mice treated with the triple combination therapy. Subsequent rejection of tumors lacking the HER-2 antigen by treatment-responsive mice without further therapy six months after the original challenge demonstrated long lasting memory and suggested that effective T cell immunity to novel, non-targeted tumor antigens (antigen spread) had occurred. These data support the clinical investigation of this triple therapy regimen, especially in cancer patients harboring PD-L1neg/low tumors unlikely to benefit from immune checkpoint blockade alone. PMID:26910562

  7. Improbability of harmful autoimmune responses resulting from immunization with HIV-1 envelope glycoproteins.

    PubMed

    Neurath, A R; Strick, N; Li, Y Y; Jiang, S

    1993-12-01

    Autoimmunity mediated by cross-reactive antibodies, elicited by HIV-1 envelope glycoproteins gp120/gp160, has been postulated to contribute to the pathogenesis of AIDS. Partial amino acid sequence homology between gp120/gp160 and several human host proteins, including MHC antigens and immunoglobulins, has been perceived as the basis for immunological cross-reactivity. Binding of antibodies from sera of HIV-1-infected individuals to selected host proteins and/or to synthetic peptides derived from them and the inhibitory activity of such sera in assays measuring the functional activity of T cells provided apparent support for the autoimmunity hypothesis, which is also relevant to the issue of safety of anti-HIV-1 vaccines. Considering the possibility that the detected autoantibodies may arise for reasons other than antibody responses to gp120/gp160, the immunological cross-reactivity between gp120/gp160 and the relevant host proteins was investigated using hyperimmune rabbit anti-gp120/gp160 and monoclonal antibodies. As determined from dilution end-point comparisons for polyclonal anti-gp120, the cross-reactivity of anti-gp120 with CD4 was undetectable (< 10(-5)%). The cross-reactivity of anti-gp120/gp160 with HLA-I and HLA-II antigens was also undetectable (< 4 x 10(-4)%) and that with other human proteins reported to have partial sequence homology with gp120/gp41 was < or = 0.013%. Anti-gp120/gp160 did not have detectable inhibitory effects in functional assays measuring proliferative T cell responses. Therefore, immunization with gp120/gp160 is unlikely to elicit harmful autoimmune responses.

  8. Multivalent dendrimeric compounds containing carbohydrates expressed on immune cells inhibit infection by primary isolates of HIV-1

    PubMed Central

    Borges, Andrew Rosa; Wieczorek, Lindsay; Johnson, Benitra; Benesi, Alan J.; Brown, Bruce K.; Kensinger, Richard D.; Krebs, Fred C.; Wigdahl, Brian; Blumenthal, Robert; Puri, Anu; McCutchan, Francine E.; Birx, Deborah L.; Polonis, Victoria R.; Schengrund, Cara-Lynne

    2010-01-01

    Specific glycosphingolipids (GSL), found on the surface of target immune cells, are recognized as alternate cell surface receptors by the human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein. In this study, the globotriose and 3’-sialyllactose carbohydrate head groups found on two GSL were covalently attached to a dendrimer core to produce two types of unique multivalent carbohydrates (MVC). These MVC inhibited HIV-1 infection of T cell lines and primary peripheral blood mononuclear cells (PBMC) by T cell line-adapted viruses or primary isolates, with IC50s ranging from 0.1 – 7.4 µg/ml. Inhibition of Env-mediated membrane fusion by MVC was also observed using a dye-transfer assay. These carbohydrate compounds warrant further investigation as a potential new class of HIV-1 entry inhibitors. The data presented also shed light on the role of carbohydrate moieties in HIV-1 virus-host cell interactions. PMID:20880566

  9. Poor functional immune recovery in aged HIV-1-infected patients following successfully treatment with antiretroviral therapy.

    PubMed

    Kasahara, Taissa M; Hygino, Joana; Andrade, Regis M; Monteiro, Clarice; Sacramento, Priscila M; Andrade, Arnaldo F B; Bento, Cleonice A M

    2015-10-01

    Aging is now a well-recognized characteristic of the HIV-infected population and both AIDS and aging are characterized by a deficiency of the T-cell compartment. The objective of the present study was to evaluate the impact of antiretroviral (ARV) therapy in recovering functional response of T cells to both HIV-1-specific ENV peptides (ENV) and tetanus toxoid (TT), in young and aged AIDS patients who responded to ARV therapy by controlling virus replication and elevating CD4(+) T cell counts. Here, we observed that proliferative response of T-cells to either HIV-1-specific Env peptides or tetanus toxoid (TT) was significantly lower in older antiretroviral (ARV)-treated patients. With regard to cytokine profile, lower levels of IFN-γ, IL-17 and IL-21, associated with elevated IL-10 release, were produced by Env- or TT-stimulated T-cells from older patients. The IL-10 neutralization by anti-IL-10 mAb did not elevate IFN-γ and IL-21 release in older patients. Finally, even after a booster dose of TT, reduced anti-TT IgG titers were quantified in older AIDS patients and it was related to both lower IL-21 and IFN-γ production and reduced frequency of central memory T-cells. Our results reveal that ARV therapy, despite the adequate recovery of CD4(+) T cell counts and suppression of viremia, was less efficient in recovering adequate immune response in older AIDS patients.

  10. Host Immune Responses in HIV-1 Infection: The Emerging Pathogenic Role of Siglecs and Their Clinical Correlates

    PubMed Central

    Mikulak, Joanna; Di Vito, Clara; Zaghi, Elisa; Mavilio, Domenico

    2017-01-01

    A better understanding of the mechanisms employed by HIV-1 to escape immune responses still represents one of the major tasks required for the development of novel therapeutic approaches targeting a disease still lacking a definitive cure. Host innate immune responses against HIV-1 are key in the early phases of the infection as they could prevent the development and the establishment of two hallmarks of the infection: chronic inflammation and viral reservoirs. Sialic acid-binding immunoglobulin-like lectins (Siglecs) belong to a family of transmembrane proteins able to dampen host immune responses and set appropriate immune activation thresholds upon ligation with their natural ligands, the sialylated carbohydrates. This immune-modulatory function is also targeted by many pathogens that have evolved to express sialic acids on their surface in order to escape host immune responses. HIV-1 envelope glycoprotein 120 (gp120) is extensively covered by carbohydrates playing active roles in life cycle of the virus. Indeed, besides forming a protecting shield from antibody recognition, this coat of N-linked glycans interferes with the folding of viral glycoproteins and enhances virus infectivity. In particular, the sialic acid residues present on gp120 can bind Siglec-7 on natural killer and monocytes/macrophages and Siglec-1 on monocytes/macrophages and dendritic cells. The interactions between these two members of the Siglec family and the sialylated glycans present on HIV-1 envelope either induce or increase HIV-1 entry in conventional and unconventional target cells, thus contributing to viral dissemination and disease progression. In this review, we address the impact of Siglecs in the pathogenesis of HIV-1 infection and discuss how they could be employed as clinic and therapeutic targets. PMID:28386256

  11. Global stability for an HIV-1 infection model with Beddington-DeAngelis incidence rate and CTL immune response

    NASA Astrophysics Data System (ADS)

    Lv, Cuifang; Huang, Lihong; Yuan, Zhaohui

    2014-01-01

    In this paper, an HIV-1 infection model with Beddington-DeAngelis incidence rate and CTL immune response is investigated. One main feature of this model is that an eclipse stage for the infected cells is included and a portion of these cells is reverted to uninfected cells. We derive the basic reproduction number R1 and the immune response reproduction number R2 for the HIV-1 infection model. By constructing Lyapunov functions, the global stabilities for the equilibria have been analyzed.

  12. Immune Correlates of Vaccine Protection Against HIV-1 Acquisition: A Review

    PubMed Central

    Corey, Lawrence; Gilbert, Peter B.; Tomaras, Georgia; Haynes, Barton F.; Pantaleo, Giuseppe; Fauci, Anthony S.

    2016-01-01

    Since 2009, the HIV vaccine field has worked to define correlates of risk associated with HIV-1 acquisition based upon the partial efficacy found in the RV144 trial. Both immunological and genetic pressure on the virus has been demonstrated by Fc antiviral antibodies largely directed at conserved regions of the V1V2 loop including antibody dependent cellular cytotoxicity (ADCC) to HIV envelope in the absence of inhibiting serum IgA antibodies. CD4+ T-cell responses to HIV envelope also correlate with reduced acquisition. Recently, NHP studies using vaccine regimens that differ from that used in RV144 also indicate that non-neutralizing antibodies are associated with protection from experimental lentivirus challenge. These immunological correlates have provided the basis for the design of a next generation of vaccine regimens to improve upon the qualitative and quantitative degree of magnitude of these immune responses on HIV acquisition. PMID:26491081

  13. Evaluation of safety and efficacy of RNAi against HIV-1 in the human immune system (Rag-2(-/-)gammac(-/-)) mouse model.

    PubMed

    ter Brake, O; Legrand, N; von Eije, K J; Centlivre, M; Spits, H; Weijer, K; Blom, B; Berkhout, B

    2009-01-01

    RNA interference (RNAi) gene therapy against HIV-1 by stable expression of antiviral short hairpin RNAs (shRNAs) can potently inhibit viral replication in T cells. Recently, a mouse model with a human immune system (HIS) was developed that can be productively infected with HIV-1. In this in vivo model, in which Rag-2(-/-)gamma(c)(-/-) mice are engrafted with human CD34(+)CD38(-) hematopoietic precursor cells, we evaluated an anti-HIV RNAi gene therapy. Human hematopoietic stem cells were transduced with a lentiviral vector expressing an shRNA against the HIV-1 nef gene (shNef) or the control vector. We observed normal development of the different cell subsets of the immune system. However, although initial transduction efficiencies were similar for both vectors, a reduced percentage of transduced human immune cells was observed for the shNef vector after establishment of the HIS in vivo. Further studies are required to fully evaluate the safety implications. When we infected the mature human CD4(+) T cells from the HIS mouse ex vivo with HIV-1, potent inhibition of viral replication was scored in shNef-expressing cells, confirming efficacy. When challenged with an shNef-resistant HIV-1 variant, equal replication was scored in control and shNef-expressing cells, confirming sequence-specificity of the RNAi therapy. We thus demonstrated that an antiviral RNAi-based gene therapy on blood stem cells leads to HIV-1-resistant T cells in vivo, an important proof of concept in the clinical development of RNAi against HIV-1.

  14. Widespread Impact of HLA Restriction on Immune Control and Escape Pathways of HIV-1

    PubMed Central

    Listgarten, Jennifer; Pfeifer, Nico; Tan, Vincent; Kadie, Carl; Walker, Bruce D.; Ndung'u, Thumbi; Shapiro, Roger; Frater, John; Brumme, Zabrina L.; Goulder, Philip J. R.; Heckerman, David

    2012-01-01

    The promiscuous presentation of epitopes by similar HLA class I alleles holds promise for a universal T-cell-based HIV-1 vaccine. However, in some instances, cytotoxic T lymphocytes (CTL) restricted by HLA alleles with similar or identical binding motifs are known to target epitopes at different frequencies, with different functional avidities and with different apparent clinical outcomes. Such differences may be illuminated by the association of similar HLA alleles with distinctive escape pathways. Using a novel computational method featuring phylogenetically corrected odds ratios, we systematically analyzed differential patterns of immune escape across all optimally defined epitopes in Gag, Pol, and Nef in 2,126 HIV-1 clade C-infected adults. Overall, we identified 301 polymorphisms in 90 epitopes associated with HLA alleles belonging to shared supertypes. We detected differential escape in 37 of 38 epitopes restricted by more than one allele, which included 278 instances of differential escape at the polymorphism level. The majority (66 to 97%) of these resulted from the selection of unique HLA-specific polymorphisms rather than differential epitope targeting rates, as confirmed by gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISPOT) data. Discordant associations between HLA alleles and viral load were frequently observed between allele pairs that selected for differential escape. Furthermore, the total number of associated polymorphisms strongly correlated with average viral load. These studies confirm that differential escape is a widespread phenomenon and may be the norm when two alleles present the same epitope. Given the clinical correlates of immune escape, such heterogeneity suggests that certain epitopes will lead to discordant outcomes if applied universally in a vaccine. PMID:22379086

  15. Broad and potent immune responses to a low dose intradermal HIV-1 DNA boosted with HIV-1 recombinant MVA among healthy adults in Tanzania☆,☆☆

    PubMed Central

    Bakari, Muhammad; Aboud, Said; Nilsson, Charlotta; Francis, Joel; Buma, Deus; Moshiro, Candida; Aris, Eric A.; Lyamuya, Eligius F.; Janabi, Mohamed; Godoy-Ramirez, Karina; Joachim, Agricola; Polonis, Victoria R.; Bråve, Andreas; Earl, Patricia; Robb, Merlin; Marovich, Mary; Wahren, Britta; Pallangyo, Kisali; Biberfeld, Gunnel; Mhalu, Fred; Sandström, Eric

    2016-01-01

    Background We conducted a phase I/II randomized placebo-controlled trial with the aim of exploring whether priming with a low intradermal dose of a multiclade, multigene HIV-1 DNA vaccine could improve the immunogenicity of the same vaccine given intramuscularly prior to boosting with a heterologous HIV-1 MVA among healthy adults in Dar es Salaam, Tanzania. Methods Sixty HIV-uninfected volunteers were randomized to receive DNA plasmid vaccine 1 mg intradermally (id), n = 20, or 3.8 mg intramuscularly (im), n = 20, or placebo, n = 20, using a needle-free injection device. DNA plasmids encoding HIV-1 genes gp160 subtype A, B, C; rev B; p17/p24 gag A, B and Rtmut B were given at weeks 0, 4 and 12. Recombinant MVA (108 pfu) expressing HIV-1 Env, Gag, Pol of CRF01_AE or placebo was administered im at month 9 and 21. Results The vaccines were well tolerated. Two weeks after the third HIV-DNA injection, 22/38 (58%) vaccinees had IFN-γ ELISpot responses to Gag. Two weeks after the first HIV-MVA boost all 35 (100%) vaccinees responded to Gag and 31 (89%) to Env. Two to four weeks after the second HIV-MVA boost, 28/29 (97%) vaccinees had IFN-γ ELISpot responses, 27 (93%) to Gag and 23 (79%) to Env. The id-primed recipients had significantly higher responses to Env than im recipients. Intracellular cytokine staining for Gag-specific IFN-γ/IL-2 production showed both CD8+ and CD4+ T cell responses. All vaccinees had HIV-specific lymphoproliferative responses. All vaccinees reacted in diagnostic HIV serological tests and 26/29 (90%) had antibodies against gp160 after the second HIV-MVA boost. Furthermore, while all of 29 vaccinee sera were negative for neutralizing antibodies against clade B, C and CRF01 AE pseudoviruses in the TZM-bl neutralization assay, in a PBMC assay, the response rate ranged from 31% to 83% positives, depending upon the clade B or CRF01_AE virus tested. This vaccine approach is safe and highly immunogenic. Low dose, id HIV-DNA priming elicited higher

  16. Cellular Immune Responses and Viral Diversity in Individuals Treated during Acute and Early HIV-1 Infection

    PubMed Central

    Altfeld, Marcus; Rosenberg, Eric S.; Shankarappa, Raj; Mukherjee, Joia S.; Hecht, Frederick M.; Eldridge, Robert L.; Addo, Marylyn M.; Poon, Samuel H.; Phillips, Mary N.; Robbins, Gregory K.; Sax, Paul E.; Boswell, Steve; Kahn, James O.; Brander, Christian; Goulder, Philip J.R.; Levy, Jay A.; Mullins, James I.; Walker, Bruce D.

    2001-01-01

    Immune responses induced during the early stages of chronic viral infections are thought to influence disease outcome. Using HIV as a model, we examined virus-specific cytotoxic T lymphocytes (CTLs), T helper cells, and viral genetic diversity in relation to duration of infection and subsequent response to antiviral therapy. Individuals with acute HIV-1 infection treated before seroconversion had weaker CTL responses directed at fewer epitopes than persons who were treated after seroconversion. However, treatment-induced control of viremia was associated with the development of strong T helper cell responses in both groups. After 1 yr of antiviral treatment initiated in acute or early infection, all epitope-specific CTL responses persisted despite undetectable viral loads. The breadth and magnitude of CTL responses remained significantly less in treated acute infection than in treated chronic infection, but viral diversity was also significantly less with immediate therapy. We conclude that early treatment of acute HIV infection leads to a more narrowly directed CTL response, stronger T helper cell responses, and a less diverse virus population. Given the need for T helper cells to maintain effective CTL responses and the ability of virus diversification to accommodate immune escape, we hypothesize that early therapy of primary infection may be beneficial despite induction of less robust CTL responses. These data also provide rationale for therapeutic immunization aimed at broadening CTL responses in treated primary HIV infection. PMID:11148221

  17. Oncolytic Poxviruses

    PubMed Central

    Chan, Winnie M.; McFadden, Grant

    2015-01-01

    Current standard treatments of cancer can prolong survival of many cancer patients but usually do not effectively cure the disease. Oncolytic virotherapy is an emerging therapeutic for the treatment of cancer that exploits replication-competent viruses to selectively infect and destroy cancerous cells while sparing normal cells and tissues. Clinical and/or preclinical studies on oncolytic viruses have revealed that the candidate viruses being tested in trials are remarkably safe and offer potential for treating many classes of currently incurable cancers. Among these candidates are vaccinia and myxoma viruses, which belong to the family Poxviridae and possess promising oncolytic features. This article describes poxviruses that are being developed for oncolytic virotherapy and summarizes the outcomes of both clinical and preclinical studies. Additionally, studies demonstrating superior efficacy when poxvirus oncolytic virotherapy is combined with conventional therapies are described. PMID:25839047

  18. Multivalent dendrimeric compounds containing carbohydrates expressed on immune cells inhibit infection by primary isolates of HIV-1

    SciTech Connect

    Rosa Borges, Andrew; Wieczorek, Lindsay; Johnson, Benitra; Benesi, Alan J.; Brown, Bruce K.; Kensinger, Richard D.; Krebs, Fred C.; Wigdahl, Brian; Blumenthal, Robert; Puri, Anu; McCutchan, Francine E.; Birx, Deborah L.; Polonis, Victoria R.; Schengrund, Cara-Lynne

    2010-12-05

    Specific glycosphingolipids (GSL), found on the surface of target immune cells, are recognized as alternate cell surface receptors by the human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein. In this study, the globotriose and 3'-sialyllactose carbohydrate head groups found on two GSL were covalently attached to a dendrimer core to produce two types of unique multivalent carbohydrates (MVC). These MVC inhibited HIV-1 infection of T cell lines and primary peripheral blood mononuclear cells (PBMC) by T cell line-adapted viruses or primary isolates, with IC{sub 50}s ranging from 0.1 to 7.4 {mu}g/ml. Inhibition of Env-mediated membrane fusion by MVC was also observed using a dye-transfer assay. These carbohydrate compounds warrant further investigation as a potential new class of HIV-1 entry inhibitors. The data presented also shed light on the role of carbohydrate moieties in HIV-1 virus-host cell interactions. -- Research Highlights: {yields}Multivalent carbohydrates (MVCs) inhibited infection of PBMCs by HIV-1. {yields}MVCs inhibited infection by T cell line-adapted viruses. {yields}MVCs inhibited infection by primary isolates of HIV-1. {yields}MVCs inhibited Env-mediated membrane fusion.

  19. Delivery of DNA HIV-1 Vaccine to the Liver Induces High and Long-lasting Humoral Immune Responses

    PubMed Central

    Raska, Milan; Moldoveanu, Zina; Novak, Jan; Hel, Zdenek; Bozja, Jadranka; Compans, Richard W.; Yang, Chinglai; Mestecky, Jiri

    2008-01-01

    The quality of immune responses induced by DNA vaccination depends on the site of DNA administration, the expression, and the properties of the encoded antigen. In the present study we demonstrate that intravenous hydrodynamic HIV-1 envelope DNA injection resulted in high levels of expression of HIV-1 envelope antigen in the liver. When compared to the administration of DNA by i.n., i.d., i.m., and i.splenic routes, hydrodynamic vaccination induced, upon DNA boosting, 40 times increase of HIV-1 envelope-specific antibodies over the preimmune levels. Hydrodynamic vaccination with 1 μg DNA induced higher humoral responses than 100 μg DNA given intramuscularly in the prime – boost regimen. High levels of envelope-specific IgG and IgA antibodies were induced in genital tract secretions after two doses of DNA followed by intranasal boosting with recombinant HIV-1 gp120 protein. Furthermore, two doses of 100 μg DNA generated interferon-gamma production in ~ 4.3 ± 1.7 % of CD8+ splenocytes after in vitro stimulation with HIV-1 envelope peptides. These results demonstrate that DNA vaccines targeted to tissues with high proteosynthetic activity, such as the liver, results in enhanced immune responses. PMID:18304708

  20. Mucosal Immunization of Lactating Female Rhesus Monkeys with a Transmitted/Founder HIV-1 Envelope Induces Strong Env-Specific IgA Antibody Responses in Breast Milk

    PubMed Central

    Fouda, Genevieve G. A.; Amos, Joshua D.; Wilks, Andrew B.; Pollara, Justin; Ray, Caroline A.; Chand, Anjali; Kunz, Erika L.; Liebl, Brooke E.; Whitaker, Kaylan; Carville, Angela; Smith, Shannon; Colvin, Lisa; Pickup, David J.; Staats, Herman F.; Overman, Glenn; Eutsey-Lloyd, Krissey; Parks, Robert; Chen, Haiyan; LaBranche, Celia; Barnett, Susan; Tomaras, Georgia D.; Ferrari, Guido; Montefiori, David C.; Liao, Hua-Xin; Letvin, Norman L.; Haynes, Barton F.

    2013-01-01

    We previously demonstrated that vaccination of lactating rhesus monkeys with a DNA prime/vector boost strategy induces strong T-cell responses but limited envelope (Env)-specific humoral responses in breast milk. To improve vaccine-elicited antibody responses in milk, hormone-induced lactating rhesus monkeys were vaccinated with a transmitted/founder (T/F) HIV Env immunogen in a prime-boost strategy modeled after the moderately protective RV144 HIV vaccine. Lactating rhesus monkeys were intramuscularly primed with either recombinant DNA (n = 4) or modified vaccinia virus Ankara (MVA) poxvirus vector (n = 4) expressing the T/F HIV Env C.1086 and then boosted twice intramuscularly with C.1086 gp120 and the adjuvant MF59. The vaccines induced Env-binding IgG and IgA as well as neutralizing and antibody-dependent cellular cytotoxicity (ADCC) responses in plasma and milk of most vaccinated animals. Importantly, plasma neutralization titers against clade C HIV variants MW965 (P = 0.03) and CAP45 (P = 0.04) were significantly higher in MVA-primed than in DNA-primed animals. The superior systemic prime-boost regimen was then compared to a mucosal-boost regimen, in which animals were boosted twice intranasally with C.1086 gp120 and the TLR 7/8 agonist R848 following the same systemic prime. While the systemic and mucosal vaccine regimens elicited comparable levels of Env-binding IgG antibodies, mucosal immunization induced significantly stronger Env-binding IgA responses in milk (P = 0.03). However, the mucosal regimen was not as potent at inducing functional IgG responses. This study shows that systemic MVA prime followed by either intranasal or systemic protein boosts can elicit strong humoral responses in breast milk and may be a useful strategy to interrupt postnatal HIV-1 transmission. PMID:23596289

  1. Poxvirus pathogenesis.

    PubMed Central

    Buller, R M; Palumbo, G J

    1991-01-01

    Poxviruses are a highly successful family of pathogens, with variola virus, the causative agent of smallpox, being the most notable member. Poxviruses are unique among animal viruses in several respects. First, owing to the cytoplasmic site of virus replication, the virus encodes many enzymes required either for macromolecular precursor pool regulation or for biosynthetic processes. Second, these viruses have a very complex morphogenesis, which involves the de novo synthesis of virus-specific membranes and inclusion bodies. Third, and perhaps most surprising of all, the genomes of these viruses encode many proteins which interact with host processes at both the cellular and systemic levels. For example, a viral homolog of epidermal growth factor is active in vaccinia virus infections of cultured cells, rabbits, and mice. At least five virus proteins with homology to the serine protease inhibitor family have been identified and one, a 38-kDa protein encoded by cowpox virus, is thought to block a host pathway for generating a chemotactic substance. Finally, a protein which has homology with complement components interferes with the activation of the classical complement pathway. Poxviruses infect their hosts by all possible routes: through the skin by mechanical means (e.g., molluscum contagiosum infections of humans), via the respiratory tract (e.g., variola virus infections of humans), or by the oral route (e.g., ectromelia virus infection of the mouse). Poxvirus infections, in general, are acute, with no strong evidence for latent, persistent, or chronic infections. They can be localized or systemic. Ectromelia virus infection of the laboratory mouse can be systemic but inapparent with no mortality and little morbidity, or highly lethal with death in 10 days. On the other hand, molluscum contagiosum virus replicates only in the stratum spinosum of the human epidermis, with little or no involvement of the dermis, and does not spread systemically from the site of

  2. HIV-1-Infected and/or Immune Activated Macrophages Regulate Astrocyte SDF-1 Production Through IL-1β

    PubMed Central

    PENG, HUI; ERDMANN, NATHAN; WHITNEY, NICHOLAS; DOU, HUANGYU; GORANTLA, SANTHI; GENDELMAN, HOWARD E.; GHORPADE, ANUJA; ZHENG, JIALIN

    2007-01-01

    Stromal cell-derived factor 1 alpha (SDF-1α) and its receptor CXCR4 play important roles in the pathogenesis of human immunodeficiency virus type one (HIV-1)-associated dementia (HAD) by serving as a HIV-1 co-receptor and affecting cell migration, virus-mediated neurotoxicity, and neurodegeneration. However, the underlying mechanisms regulating SDF-1 production during disease are not completely understood. In this report we investigated the role of HIV-1 infected and immune competent macrophage, the principal target cell and mediator of neuronal injury and death in HAD, in regulating SDF-1 production by astrocytes. Our data demonstrated that astrocytes are the primary cell type expressing SDF-1 in the brain. Immune-activated or HTV-1-infected human monocyte-derived-macrophage (MDM) conditioned media (MCM) induced a substantial increase in SDF-1 production by human astrocytes. This SDF-1 production was directly dependent on MDM IL-1β following both viral and immune activation. The MCM-induced production of SDF-1 was prevented by IL-1β receptor antagonist (IL-1Ra) and IL-1β siRNA treatment of human MDM. These laboratory observations were confirmed in severe combined immunodeficient (SCID) mice with HIV-1 encephalitis (HIVE). In these HIVE mice, reactive astrocytes showed a significant increase in SDF-1 expression, as observed by immunocytochemical staining. Similarly, SDF-1 mRNA levels were increased in the encephalitic region as measured by real time RT-PCR, and correlated with IL-1β mRNA expression. These observations provide direct evidence that IL-1β, produced from HIV-1-infected and/or immune competent macrophage, induces production of SDF-1 by astrocytes, and as such contribute to ongoing SDF-1 mediated CNS regulation during HAD. PMID:16944452

  3. HIV-1 Structural Proteins Serve as PAMPs for TLR2 Heterodimers Significantly Increasing Infection and Innate Immune Activation

    PubMed Central

    Henrick, Bethany M.; Yao, Xiao-Dan; Rosenthal, Kenneth Lee

    2015-01-01

    Immune activation is critical to HIV infection and pathogenesis; however, our understanding of HIV innate immune activation remains incomplete. Recently we demonstrated that soluble TLR2 (sTLR2) physically inhibited HIV-induced NFκB activation and inflammation, as well as HIV-1 infection. In light of these findings, we hypothesized that HIV-1 structural proteins may serve as pathogen-associated molecular patterns (PAMPs) for cellular TLR2 heterodimers. These studies made use of primary human T cells and TZMbl cells stably transformed to express TLR2 (TZMbl-2). Our results demonstrated that cells expressing TLR2 showed significantly increased proviral DNA compared to cells lacking TLR2, and mechanistically this may be due to a TLR2-mediated increased CCR5 expression. Importantly, we show that HIV-1 structural proteins, p17, p24, and gp41, act as viral PAMPs signaling through TLR2 and its heterodimers leading to significantly increased immune activation via the NFκB signaling pathway. Using co-immunoprecipitation and a dot blot method, we demonstrated direct protein interactions between these viral PAMPs and TLR2, while only p17 and gp41 bound to TLR1. Specifically, TLR2/1 heterodimer recognized p17 and gp41, while p24 lead to immune activation through TLR2/6. These results were confirmed using TLR2/1 siRNA knock down assays which ablated p17 and gp41-induced cellular activation and through studies of HEK293 cells expressing selected TLRs. Interestingly, our results show in the absence of TLR6, p24 bound to TLR2 and blocked p17 and gp41-induced activation, thus providing a novel mechanism by which HIV-1 can manipulate innate sensing. Taken together, our results identified, for the first time, novel HIV-1 PAMPs that play a role in TLR2-mediated cellular activation and increased proviral DNA. These findings have important implications for our fundamental understanding of HIV-1 immune activation and pathogenesis, as well as HIV-1 vaccine development. PMID:26347747

  4. Immunization with HIV-1 gp41 subunit virosomes induces mucosal antibodies protecting nonhuman primates against vaginal SHIV challenges.

    PubMed

    Bomsel, Morgane; Tudor, Daniela; Drillet, Anne-Sophie; Alfsen, Annette; Ganor, Yonatan; Roger, Marie-Gaëlle; Mouz, Nicolas; Amacker, Mario; Chalifour, Anick; Diomede, Lorenzo; Devillier, Gilles; Cong, Zhe; Wei, Qiang; Gao, Hong; Qin, Chuan; Yang, Gui-Bo; Zurbriggen, Rinaldo; Lopalco, Lucia; Fleury, Sylvain

    2011-02-25

    Human immunodeficiency virus (HIV)-1 is mainly transmitted mucosally during sexual intercourse. We therefore evaluated the protective efficacy of a vaccine active at mucosal sites. Macaca mulatta monkeys were immunized via both the intramuscular and intranasal routes with an HIV-1 vaccine made of gp41-subunit antigens grafted on virosomes, a safe delivery carrier approved in humans with self-adjuvant properties. Six months after 13 vaginal challenges with simian-HIV (SHIV)-SF162P3, four out of five vaccinated animals remained virus-negative, and the fifth was only transiently infected. None of the five animals seroconverted to p27gag-SIV. In contrast, all 6 placebo-vaccinated animals became infected and seroconverted. All protected animals showed gp41-specific vaginal IgAs with HIV-1 transcytosis-blocking properties and vaginal IgGs with neutralizing and/or antibody-dependent cellular-cytotoxicity activities. In contrast, plasma IgGs totally lacked virus-neutralizing activity. The protection observed challenges the paradigm whereby circulating antiviral antibodies are required for protection against HIV-1 infection and may serve in designing a human vaccine against HIV-1-AIDS.

  5. Recombinant measles viruses expressing single or multiple antigens of human immunodeficiency virus (HIV-1) induce cellular and humoral immune responses.

    PubMed

    Liniger, Matthias; Zuniga, Armando; Morin, Teldja Neige Azzouz; Combardiere, Behazine; Marty, Rene; Wiegand, Marian; Ilter, Orhan; Knuchel, Marlyse; Naim, Hussein Y

    2009-05-26

    Recombinant measles viruses (rMV) based on the live attenuated measles vaccine strain (MVb) expressing antigens of HIV-1 clade B were generated by reverse genetics. Recombinants expressing single or double antigens of HIV-1 (rMV-HIV) were genetically highly stable on human diploid cells. The production process of these viruses was essentially similar to the parental MV strain, yielding comparative end titers. Immunization of tg-mice by different regimens and formulations showed potent humoral and cellular immune responses against MV and HIV antigens. Recombinant MV-HIV expressing Gag protein conferred protective immunity in tg-mice after a high-dose pseudochallenge with recombinant vaccinia virus. In addition, rMV-HIV boosted anti-HIV antibodies, in the presence of pre-existing anti-vector antibodies.

  6. Structural basis of evasion of cellular adaptive immunity by HIV-1 Nef

    SciTech Connect

    Jia, Xiaofei; Singh, Rajendra; Homann, Stefanie; Yang, Haitao; Guatelli, John; Xiong, Yong

    2012-10-24

    The HIV-1 protein Nef inhibits antigen presentation by class I major histocompatibility complex (MHC-I). We determined the mechanism of this activity by solving the crystal structure of a protein complex comprising Nef, the MHC-I cytoplasmic domain (MHC-I CD) and the {mu}1 subunit of the clathrin adaptor protein complex 1. A ternary, cooperative interaction clamps the MHC-I CD into a narrow binding groove at the Nef-{mu}1 interface, which encompasses the cargo-recognition site of {mu}1 and the proline-rich strand of Nef. The Nef C terminus induces a previously unobserved conformational change in {mu}1, whereas the N terminus binds the Nef core to position it optimally for complex formation. Positively charged patches on {mu}1 recognize acidic clusters in Nef and MHC-I. The structure shows how Nef functions as a clathrin-associated sorting protein to alter the specificity of host membrane trafficking and enable viral evasion of adaptive immunity.

  7. Role of Fc-mediated antibody function in protective immunity against HIV-1.

    PubMed

    Lewis, George K

    2014-05-01

    The importance of Fc-mediated effector function in protective immunity to HIV-1 (hereafter referred to simply as HIV) is becoming increasingly apparent. A large of number of studies in natural infection cohorts, spanning the last 26 years, have associated Fc-mediated effector function, particularly antibody-dependent cellular cytotoxicity, with a favourable clinical course. These studies strongly suggest a role for Fc-mediated effector function in the post-infection control of viraemia. More recently, studies in both humans and non-human primates (NHPs) also implicate Fc-mediated effector function in blocking HIV acquisition. Accordingly, this review will discuss the results supporting a role of Fc-mediated effector function in both blocking acquisition and post-infection control of viraemia. Parallel studies in NHPs and humans will be compared for common themes. Context for this discussion will be provided by summarizing the temporal emergence of key host and virological events over the course of an untreated HIV infection framing where, when and how Fc-mediated effector function might be protective. A hypothesis that Fc-mediated effector function protects primarily in the early stages of both acquisition and post-infection control of viraemia will be developed.

  8. Life stressors and coping style are associated with immune measures in HIV-1 infection--a preliminary report.

    PubMed

    Goodkin, K; Fuchs, I; Feaster, D; Leeka, J; Rishel, D D

    1992-01-01

    Life stressors and coping style have been associated with alterations in cellular immunity similar to those seen in HIV-1 infection. The interval between infection with HIV-1 and the development of AIDS is lengthy and highly variable. This pilot study investigated whether life stressors and coping style may account for a portion of this variation. A sample of eleven asymptomatic HIV-1 seropositive homosexual male volunteers responding to a local advertisement was assessed on life stressors, coping style and cellular phenotypic and functional immune measures--T4 "helper" cell/T8 "suppressor" cell ratio, T4 cell count, total lymphocyte count, and natural killer cell cytotoxicity. Significant associations were observed for both major life stressor impact over the previous year and passive coping style use with the total lymphocyte count; higher life stressor impact and passive coping style use were associated with lower total lymphocyte counts. Similarly, a trend in the same direction was found for the relationship of these two measures with the count of T4 cells, which are directly infected and killed by HIV-1. It is well documented that decrements in T4 cell and total lymphocyte counts are powerful predictors of subsequent clinical progression to AIDS. These preliminary findings suggest that life stressors and coping style may also be predictors of the development of AIDS.

  9. Effects of alpha interferon treatment on intrinsic anti-HIV-1 immunity in vivo.

    PubMed

    Abdel-Mohsen, Mohamed; Deng, Xutao; Liegler, Teri; Guatelli, John C; Salama, Mohamed S; Ghanem, Hussam El-din A; Rauch, Andri; Ledergerber, Bruno; Deeks, Steven G; Günthard, Huldrych F; Wong, Joseph K; Pillai, Satish K

    2014-01-01

    Alpha interferon (IFN-α) suppresses human immunodeficiency virus type 1 (HIV-1) replication in vitro by inducing cell-intrinsic retroviral restriction mechanisms. We investigated the effects of IFN-α/ribavirin (IFN-α/riba) treatment on 34 anti-HIV-1 restriction factors in vivo. Expression of several anti-HIV-1 restriction factors was significantly induced by IFN-α/riba in HIV/hepatitis C virus (HCV)-coinfected individuals. Fold induction of cumulative restriction factor expression in CD4(+) T cells was significantly correlated with viral load reduction during IFN-α/riba treatment (r(2) = 0.649; P < 0.016). Exogenous IFN-α induces supraphysiologic restriction factor expression associated with a pronounced decrease in HIV-1 viremia.

  10. Loss of Th22 cells is associated with increased immune activation and IDO-1 activity in HIV-1 infection.

    PubMed

    Page, Emma E; Greathead, Louise; Metcalf, Rebecca; Clark, Sally-Ann; Hart, Melanie; Fuchs, Dietmar; Pantelidis, Panagiotis; Gotch, Frances; Pozniak, Anton; Nelson, Mark; Boasso, Adriano; Gazzard, Brian; Kelleher, Peter

    2014-11-01

    Immune activation plays a key role in the immunopathogenesis of HIV-1 infection. Microbial translocation, secondary to loss of epithelial integrity and mucosal immune deficiency, is believed to contribute to systemic immune activation. Interleukin 22 maintains intestinal epithelial barrier integrity and stimulates the secretion of antimicrobial peptides that limit bacterial dissemination and intestinal inflammation. Interleukin 22 is secreted by CD4 T-helper (Th)22 cells independently of interleukin 17A and interferon γ. Th22 cells are characterized by the expression of chemokine receptors (CCR)4, CCR6, and CCR10. We analyzed the frequency of Th22, Th17, Th1, and CD4 T regulatory (Treg) cells, markers of immune activation (expression of CD38 on CD8 T cells, neopterin, soluble CD14), microbial translocation (lipopolysaccharide-binding protein and 16s ribosomal DNA), and indoleamine 2,3-dioxygenase 1 activity in peripheral blood of antiretroviral therapy (ART)-experienced and ART-naive HIV-1-infected patients and healthy controls. We showed a significant reduction in the frequency of Th22 cells in HIV ART-naive patients compared with the healthy controls and HIV ART-experienced patients. We observed a shift away from Th22 and Th17 to Treg cells, which was partially reversed by effective ART. Markers of immune activation negatively correlated with Th22 and Th17 proportions, and with Th22:Treg and Th17:Treg ratios in ART-naive patients. Increased indoleamine 2,3-dioxygenase 1 activity negatively correlated with Th22:Treg and Th17:Treg ratios in the ART-naive group. Loss of Th22 cells and disruption in the balance of Th22 and Treg cells may contribute toward systemic immune activation and mucosal immune deficiency during HIV-1 infection.

  11. Diversion of HIV-1 Vaccine-induced Immunity by gp41-Microbiota Cross-reactive Antibodies

    PubMed Central

    Williams, Wilton B; Liao, Hua-Xin; Moody, M. Anthony; Kepler, Thomas B.; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M.; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E.; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C.; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, Julie; Mascola, John R.; Koup, Richard A; Corey, Lawrence; Nabel, Gary J.; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S.; Baden, Lindsey R.; Tomaras, Georgia D.; Haynes, Barton F.

    2015-01-01

    A HIV-1 DNA prime-recombinant Adenovirus Type 5 (rAd5) boost vaccine failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells was to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies (mAbs) were non-neutralizing, and frequently polyreactive with host and environmental antigens including intestinal microbiota (IM). Next generation sequencing of an IGHV repertoire prior to vaccination revealed an Env-IM cross-reactive Ab that was clonally-related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy. PMID:26229114

  12. Functional adaptation of Nef to the immune milieu of HIV-1 infection in vivo.

    PubMed

    Lewis, Martha J; Balamurugan, Arumugam; Ohno, Ayako; Kilpatrick, Stephanie; Ng, Hwee L; Yang, Otto O

    2008-03-15

    Nef-mediated down-regulation of MHC class I (MHC-I) molecules on HIV-1-infected cells has been proposed to enhance viral persistence through evasion of host CTLs. This conclusion is based largely on demonstrations that Nef from laboratory HIV-1 strains reduces the susceptibility of infected cells to CTL killing in vitro. However, the function and role of Nef-mediated MHC-I down-regulation in vivo have not been well described. To approach this issue, nef quasispecies from chronically HIV-1-infected individuals were cloned into recombinant reporter viruses and tested for their ability to down-regulate MHC-I molecules from the surface of infected cells. The level of function varied widely between individuals, and although comparison to the immunologic parameters of blood CD4(+) T lymphocyte count and breadth of the HIV-1-specific CTL response showed positive correlations, no significant correlation was found in comparison to plasma viremia. The ability of in vivo-derived Nef to down-regulate MHC-I predicted the resistance of HIV-1 to suppression by CTL. Taken together, these data demonstrate the functionality of Nef to down-regulate MHC-I in vivo during stable chronic infection, and suggest that this function is maintained by the need of HIV-1 to cope with the antiviral CTL response.

  13. The inter-relation of maternal immune competence, HIV-1 viral load, and nutritional status in preventing vertical transmission: an alternative to chemoprophylaxis?

    PubMed

    Moran, P J; Welles, S L; Williams, M A

    1998-11-01

    As the human immunodeficiency virus (HIV) global pandemic moves towards the end of its second decade, women of reproductive age throughout the world have been shown to be increasingly at risk for acquiring HIV-1 infection. Recently, the focus for preventive measures has expanded to include preventing the perinatal transmission of HIV-1 to fetuses and newborns. This manuscript reviews the available literature that examines risk factors for perinatal transmission, immunopathogenesis of HIV-1 infection, and the role that antioxidant micronutrients play in modulating immune response to HIV-1 disease progression. The available information provides a compelling case for the design of studies that evaluate the extent to which maternal HIV-1 viremia and disease progression are modulated by her nutritional status. Should results from these studies confirm that antioxidant micronutrient status is inversely related to HIV-1 RNA load, particularly in economically vulnerable populations, carefully designed and executed supplementation trials would be warranted.

  14. Immune Activation at Sites of HIV/TB Co-Infection Contributes to the Pathogenesis of HIV-1 Disease

    PubMed Central

    Meng, Qinglai; Sayin, Ismail; Canaday, David H.; Mayanja-Kizza, Harriet; Baseke, Joy; Toossi, Zahra

    2016-01-01

    Systemic immune activation is critical to the pathogenesis of HIV-1 disease, and is accentuated in HIV/TB co-infected patients. The contribution of immune activation at sites of HIV/TB co-infection to viral activity, CD4 T cell count, and productive HIV-1 infection remain unclear. In this study, we measured markers of immune activation both in pleural fluid and plasma, and in T cells in pleural fluid mononuclear cell (PFMC) and peripheral blood mononuclear cell (PBMC) in HIV/TB co-infected subjects. The relationship between soluble and T cell activation markers with viral load in pleural fluid and blood CD4 T cell count were assessed. The T cell phenotype and activation status of HIV-1 p24 + T cells in PFMC and PBMC from HIV/TB patients were determined. We found that T cell and macrophage-specific and non-specific soluble markers of immune activation, sCD27, sCD163, IL1Ra, and sCD14, were higher in pleural fluid as compared to plasma from HIV/TB co-infected subjects, and higher as compared to pleural fluid from TB mono-infected subjects. Intestinal fatty acid-binding protein, a marker of intestinal tract damage, in plasma from HIV/TB co-infected patients was not different than that in HIV+ subjects. Expression of HLADR and CD38 double positive (HLADR/CD38) on CD4 T cells, and CD69+ on CD8 T cells correlated with pleural fluid viral load, and inversely with blood CD4 T cell count. Higher expression of HLADR/CD38 and CCR5 on CD4 T cells, and HLADR/CD38 and CD69 on CD8 T cells in PFMC were limited to effector memory populations. HIV-1 p24+ CD8 negative (includes CD4 + and double negative T cells) effector memory T cells in PFMC had higher expression of HLADR/CD38, Ki67, and CCR5 compared to HIV-1 p24- CD8 negative PFMC. Cumulatively, these data indicate that sites of HIV/TB co-infection are the source of intense immune activation. PMID:27870882

  15. Keeping your armour intact: how HIV-1 evades detection by the innate immune system: HIV-1 capsid controls detection of reverse transcription products by the cytosolic DNA sensor cGAS.

    PubMed

    Maelfait, Jonathan; Seiradake, Elena; Rehwinkel, Jan

    2014-07-01

    HIV-1 infects dendritic cells (DCs) without triggering an effective innate antiviral immune response. As a consequence, the induction of adaptive immune responses controlling virus spread is limited. In a recent issue of Immunity, Lahaye and colleagues show that intricate interactions of HIV capsid with the cellular cofactor cyclophilin A (CypA) control infection and innate immune activation in DCs. Manipulation of HIV-1 capsid to increase its affinity for CypA results in reduced virus infectivity and facilitates access of the cytosolic DNA sensor cGAS to reverse transcribed DNA. This in turn induces a strong host response. Here, we discuss these findings in the context of recent developments in innate immunity and consider the implications for disease control and vaccine design.

  16. MicroRNA-29 family expression and its relation to antiviral immune response and viro-immunological markers in HIV-1-infected patients.

    PubMed

    Monteleone, Katia; Selvaggi, Carla; Cacciotti, Giulia; Falasca, Francesca; Mezzaroma, Ivano; D'Ettorre, Gabriella; Turriziani, Ombretta; Vullo, Vincenzo; Antonelli, Guido; Scagnolari, Carolina

    2015-02-12

    Several in vitro studies suggested the microRNA-29 (miRNA-29) family is involved in regulating HIV-1 and modulating the expression of interleukin (IL)-32, an anti-HIV-1 cytokine. To investigate the contribution of the miRNA-29 family to HIV-1 infection in vivo, we compared miRNA-29 expression in PBMC collected from 58 HIV-1-infected patients, naïve for antiretroviral therapy, and 21 gender- and age-matched HIV-1 seronegative healthy donors, using RT-Taqman assays. The relation between miRNA-29 levels and HIV-1 viro-immunological markers and the activation rate of antiviral immune response were also evaluated. In addition, we profiled miRNA-29 expression in CD4+ T lymphocytes and CD14+ monocytes collected from 5 antiretroviral treated HIV-1 infected patients. miRNA-29b levels were higher in HIV-1-infected patients than in the control group (p < 0.001). There were no correlations with either HIV-1 RNA levels or CD4+ T count, whereas a significant correlation was found between miRNA-29-a/c levels and integrated HIV-1 DNA (miRNA-29a: p = 0.009, r = -0.448; miRNA-29c: p = 0.029; r = -0.381). When the HIV-1-infected patients were grouped on the basis of their plasma HIV-1 RNA and CD4+ T cell count, we also found that patients expressing the lowest levels of miRNA-29c showed high viraemia, low CD4+ T cell count and high levels of integrated HIV-1 DNA. Moreover, miRNA-29b levels were correlated with those of IL-32nonα (p = 0.028; r = -0.298). Patients expressing higher levels of miRNA-29b showed lower levels of MxA, an interferon-stimulated gene, also induced by IL-32 (p = 0.006 r = -0.397). Lastly, we found that CD4+ T lymphocytes and CD14+ monocytes shared similar miRNA-29a/b/c expression patterns but the amount of miRNA-29a/b/c, IL-32 isoforms and MxA were highly variable in these two cellular subsets. The miRNA-29 family could influence the clinical progression of HIV-1 infection, the HIV-1 proviral load and the innate immune

  17. Low levels of HIV-1 RNA detected in the cerebrospinal fluid after up to 10 years of suppressive therapy are associated with local immune activation

    PubMed Central

    Dahl, Viktor; Peterson, Julia; Fuchs, Dietmar; Gisslen, Magnus; Palmer, Sarah; Price, Richard W.

    2015-01-01

    Objective and design Though combination antiretroviral therapy reduces the concentration of HIV-1 RNA in both plasma and cerebrospinal fluid (CSF) below the detection limit of clinical assays, low levels of HIV-1 RNA are frequently detectable in plasma using more sensitive assays. We examined the frequency and magnitude of persistent low-level HIV-1 RNA in CSF and its relation to the central nervous system (CNS) immune activation. Methods CSF and plasma HIV-1 RNA were measured using the single-copy assay with a detection limit of 0.3 copies/ml in 70 CSF and 68 plasma samples from 45 treated HIV-1-infected patients with less than 40 copies/ml of HIV-1 RNA in both fluids by standard clinical assays. We also measured CSF neopterin to assess intrathecal immune activation. Theoretical drug exposure was estimated using the CNS penetration-efficacy score of treatment regimens. Results CSF HIV-1 RNA was detected in 12 of the 70 CSF samples (17%) taken after up to 10 years of suppressive therapy, compared to 39 of the 68 plasma samples (57%) with a median concentration of less than 0.3 copies/ml in CSF compared to 0.3 copies/ml in plasma (P <0.0001). CSF samples with detectable HIV-1 RNA had higher CSF neopterin levels (mean 8.2 compared to 5.7 nmol/l; P =0.0085). Patients with detectable HIV-1 RNA in CSF did not differ in pretreatment plasma HIV-1 RNA levels, nadir CD4+ cell count or CNS penetration-efficacy score. Conclusion Low-level CSF HIV-1 RNA and its association with elevated CSF neopterin highlight the potential for the CNS to serve as a viral reservoir and for persistent infection to cause subclinical CNS injury. PMID:25022595

  18. Standardized assessment of NAb responses elicited in rhesus monkeys immunized with single- or multi-clade HIV-1 envelope immunogens.

    PubMed

    Seaman, Michael S; Leblanc, Daniel F; Grandpre, Lauren E; Bartman, Melissa T; Montefiori, David C; Letvin, Norman L; Mascola, John R

    2007-10-10

    The genetic diversity of HIV-1 envelope glycoproteins (Env) remains a major obstacle to the development of an antibody-based AIDS vaccine. The present studies examine the breadth and magnitude of neutralizing antibody (NAb) responses in rhesus monkeys after immunization with DNA prime-recombinant adenovirus (rAd) boost vaccines encoding either single or multiple genetically distant Env immunogens, and subsequently challenged with a pathogenic simian-human immunodeficiency virus (SHIV-89.6P). Using a standardized multi-tier panel of reference Env pseudoviruses for NAb assessment, we show that monkeys immunized with a mixture of Env immunogens (clades A, B, and C) exhibited a greater breadth of NAb activity against neutralization-sensitive Tier 1 viruses following both vaccination and challenge compared to monkeys immunized with a single Env immunogen (clade B or C). However, all groups of Env-vaccinated monkeys demonstrated only limited neutralizing activity against Tier 2 pseudoviruses, which are more characteristic of the neutralization sensitivity of circulating HIV-1. Notably, the development of a post-challenge NAb response against SHIV-89.6P was similar in monkeys receiving either clade B, clade C, or clade A+B+C Env immunogens, suggesting cross-clade priming of NAb responses. In addition, vaccines encoding Env immunogens heterologous to SHIV-89.6P primed for a rapid anamnestic NAb response following infection compared to vaccines lacking an Env component. These results show that DNA/rAd immunization with multiple diverse Env immunogens is a viable approach for enhancing the breadth of NAb responses against HIV-1, and suggest that Env immunogens can prime for anamnestic NAb responses against a heterologous challenge virus.

  19. Effect of humoral immunity on HIV-1 dynamics with virus-to-target and infected-to-target infections

    NASA Astrophysics Data System (ADS)

    Elaiw, A. M.; Raezah, A. A.; Alofi, A. S.

    2016-08-01

    We consider an HIV-1 dynamics model by incorporating (i) two routes of infection via, respectively, binding of a virus to a receptor on the surface of a target cell to start genetic reactions (virus-to-target infection), and the direct transmission from infected cells to uninfected cells through the concept of virological synapse in vivo (infected-to-target infection); (ii) two types of distributed-time delays to describe the time between the virus or infected cell contacts an uninfected CD4+ T cell and the emission of new active viruses; (iii) humoral immune response, where the HIV-1 particles are attacked by the antibodies that are produced from the B lymphocytes. The existence and stability of all steady states are completely established by two bifurcation parameters, R 0 (the basic reproduction number) and R 1 (the viral reproduction number at the chronic-infection steady state without humoral immune response). By constructing Lyapunov functionals and using LaSalle's invariance principle, we have proven that, if R 0 ≤ 1 , then the infection-free steady state is globally asymptotically stable, if R 1 ≤ 1 < R 0 , then the chronic-infection steady state without humoral immune response is globally asymptotically stable, and if R 1 > 1 , then the chronic-infection steady state with humoral immune response is globally asymptotically stable. We have performed numerical simulations to confirm our theoretical results.

  20. Immune Compromise in HIV-1/HTLV-1 Coinfection With Paradoxical Resolution of CD4 Lymphocytosis During Antiretroviral Therapy: A Case Report.

    PubMed

    Rockwood, N; Cook, L; Kagdi, H; Basnayake, S; Bangham, C R M; Pozniak, A L; Taylor, G P

    2015-12-01

    Human immunodeficiency virus type-1 (HIV-1) and human T lymphotropic virus type-1 (HTLV-1) infections have complex effects on adaptive immunity, with specific tropism for, but contrasting effects on, CD4 T lymphocytes: depletion with HIV-1, proliferation with HTLV-1. Impaired T lymphocyte function occurs early in HIV-1 infection but opportunistic infections (OIs) rarely occur in the absence of CD4 lymphopenia. In the unusual case where a HIV-1 infected individual with a high CD4 count presents with recurrent OIs, a clinician is faced with the possibility of a second underlying comorbidity. We present a case of pseudo-adult T cell leukemia/lymphoma (ATLL) in HIV-1/HTLV-1 coinfection where the individual fulfilled Shimoyama criteria for chronic ATLL and had pulmonary Mycobacterium kansasii, despite a high CD4 lymphocyte count. However, there was no evidence of clonal T-cell proliferation by T-cell receptor gene rearrangement studies nor of monoclonal HTLV-1 integration by high-throughput sequencing. Mutually beneficial interplay between HIV-1 and HTLV-1, maintaining high level HIV-1 and HTLV-1 viremia and proliferation of poorly functional CD4 cells despite chronicity of infection is a postulated mechanism. Despite good microbiological response to antimycobacterial therapy, the patient remained systemically unwell with refractory anemia. Subsequent initiation of combined antiretroviral therapy led to paradoxical resolution of CD4 T lymphocytosis as well as HIV-1 viral suppression and decreased HTLV-1 proviral load. This is proposed to be the result of attenuation of immune activation post-HIV virological control. This case illustrates the importance of screening for HTLV-1 in HIV-1 patients with appropriate clinical presentation and epidemiological risk factors and explores mechanisms for the complex interactions on HIV-1/HTLV-1 adaptive immunity.

  1. Poxvirus antigen staining of immune cells as a biomarker to predict disease outcome in monkeypox and cowpox virus infection in non-human primates.

    PubMed

    Song, Haifeng; Janosko, Krisztina; Johnson, Reed F; Qin, Jing; Josleyn, Nicole; Jett, Catherine; Byrum, Russell; St Claire, Marisa; Dyall, Julie; Blaney, Joseph E; Jennings, Gerald; Jahrling, Peter B

    2013-01-01

    Infection of non-human primates (NHPs) such as rhesus and cynomolgus macaques with monkeypox virus (MPXV) or cowpox virus (CPXV) serve as models to study poxvirus pathogenesis and to evaluate vaccines and anti-orthopox therapeutics. Intravenous inoculation of macaques with high dose of MPXV (>1-2×10(7) PFU) or CPXV (>10(2) PFU) results in 80% to 100% mortality and 66 to 100% mortality respectively. Here we report that NHPs with positive detection of poxvirus antigens in immune cells by flow cytometric staining, especially in monocytes and granulocytes succumbed to virus infection and that early positive pox staining is a strong predictor for lethality. Samples from four independent studies were analyzed. Eighteen NHPs from three different experiments were inoculated with two different MPXV strains at lethal doses. Ten NHPs displayed positive pox-staining and all 10 NHPs reached moribund endpoint. In contrast, none of the three NHPs that survived anticipated lethal virus dose showed apparent virus staining in the monocytes and granulocytes. In addition, three NHPs that were challenged with a lethal dose of MPXV and received cidofovir treatment were pox-antigen negative and all three NHPs survived. Furthermore, data from a CPXV study also demonstrated that 6/9 NHPs were pox-antigen staining positive and all 6 NHPs reached euthanasia endpoint, while the three survivors were pox-antigen staining negative. Thus, we conclude that monitoring pox-antigen staining in immune cells can be used as a biomarker to predict the prognosis of virus infection. Future studies should focus on the mechanisms and implications of the pox-infection of immune cells and the correlation between pox-antigen detection in immune cells and disease progression in human poxviral infection.

  2. Poxvirus Antigen Staining of Immune Cells as a Biomarker to Predict Disease Outcome in Monkeypox and Cowpox Virus Infection in Non-Human Primates

    PubMed Central

    Song, Haifeng; Janosko, Krisztina; Johnson, Reed F.; Qin, Jing; Josleyn, Nicole; Jett, Catherine; Byrum, Russell; Claire, Marisa St.; Dyall, Julie; Blaney, Joseph E.; Jennings, Gerald; Jahrling, Peter B.

    2013-01-01

    Infection of non-human primates (NHPs) such as rhesus and cynomolgus macaques with monkeypox virus (MPXV) or cowpox virus (CPXV) serve as models to study poxvirus pathogenesis and to evaluate vaccines and anti-orthopox therapeutics. Intravenous inoculation of macaques with high dose of MPXV (>1–2×107 PFU) or CPXV (>102 PFU) results in 80% to 100% mortality and 66 to 100% mortality respectively. Here we report that NHPs with positive detection of poxvirus antigens in immune cells by flow cytometric staining, especially in monocytes and granulocytes succumbed to virus infection and that early positive pox staining is a strong predictor for lethality. Samples from four independent studies were analyzed. Eighteen NHPs from three different experiments were inoculated with two different MPXV strains at lethal doses. Ten NHPs displayed positive pox-staining and all 10 NHPs reached moribund endpoint. In contrast, none of the three NHPs that survived anticipated lethal virus dose showed apparent virus staining in the monocytes and granulocytes. In addition, three NHPs that were challenged with a lethal dose of MPXV and received cidofovir treatment were pox-antigen negative and all three NHPs survived. Furthermore, data from a CPXV study also demonstrated that 6/9 NHPs were pox-antigen staining positive and all 6 NHPs reached euthanasia endpoint, while the three survivors were pox-antigen staining negative. Thus, we conclude that monitoring pox-antigen staining in immune cells can be used as a biomarker to predict the prognosis of virus infection. Future studies should focus on the mechanisms and implications of the pox-infection of immune cells and the correlation between pox-antigen detection in immune cells and disease progression in human poxviral infection. PMID:23577120

  3. Replication of HIV-1 deleted Nef mutants in chronically immune activated human T cells.

    PubMed

    Shapira-Nahor, Orit; Maayan, Shlomo; Peden, Keith W C; Rabinowitz, Ruth; Schlesinger, Michael; Alian, Akram; Panet, Amos

    2002-11-10

    Lymphocytes (PBMC) obtained from blood of HIV-sera negative Ethiopian immigrants (ETH) were highly susceptible to HIV-1 infection in vitro with no need for stimulation by mitogens. As the HIV nef gene product has been shown to enhance viral replication in stimulated primary lymphocytes, we investigated in this work the role of Nef in viral replication in the ETH cells. Lymphocytes obtained from ETH individuals supported high replication of wild-type HIV-1 and low but significant replication level of the two deleted Nef mutants (encode truncated Nef proteins consisting only of either the first 35 or the first 86 amino acids of Nef). In contrast, no replication was observed in nonactivated cells obtained from non-ETH individuals. After activation of the PBMC from ETH individuals with PHA, replication of both wild-type strains and the two deleted Nef mutant viruses further increased. The CD4(+) T cells of ETH individuals exhibited elevated levels of the surface activation markers CD45RO and HLA-DR, compared with T cells derived from non-ETH group. Likewise, expression of the chemokine receptors CCR5 and CXCR4 on these cells was higher in the ETH group than in the non-ETH group. Replication of HIV-1 wild-type and the isogenic-deleted Nef mutants was significantly correlated with the proportion of ETH cells expressing CD45RO and the chemokine receptors. This study suggests that HIV-1 may respond differently to several activation states characteristic of T cells. One activation state, defined by chronically activated lymphocytes from ETH individuals, is permissive to the wild-type HIV-1 and, to a lesser degree, to the Nef mutants. Further activation of these cells by exogenous stimuli enhances replication of the virus. Our results support the notion that Nef enhances the basal level of T cell activation and consequently, viral replication.

  4. Modulation of Th1/Th2 immune responses to HIV-1 Tat by new pro-GSH molecules.

    PubMed

    Fraternale, Alessandra; Paoletti, Maria Filomena; Dominici, Sabrina; Buondelmonte, Costantina; Caputo, Antonella; Castaldello, Arianna; Tripiciano, Antonella; Cafaro, Aurelio; Palamara, Anna Teresa; Sgarbanti, Rossella; Garaci, Enrico; Ensoli, Barbara; Magnani, Mauro

    2011-09-16

    We have previously demonstrated that in Ova-immunized mice the increase in intra-macrophage thiol pool induced by pro-GSH molecules modulates the Th1/Th2 balance in favour of a Th1-type immune response. We show now that the same molecules can support a Th1-type over Th2-type immunity against Tat, which is an early HIV-1 regulatory protein and a Th1 polarizing immunomodulator that is increasingly considered in new anti-HIV vaccination strategies. Our results indicate that Tat-immunized mice pre-treated with the C4 (n-butanoyl) derivative of reduced glutathione (GSH-C4) or a pro-drug of N-acetylcysteine (NAC) and beta-mercaptoethylamine (MEA) (I-152), have decreased levels of anti-Tat IgG1 as well as increased levels of anti-Tat IgG2a and IgG2b isotypes suggesting a Th1-type response. Moreover, Th1-(IFN-γ and IL-2) Ag-specific cellular responses were detected by ELISPOT assay in splenocytes of the same animals as well as an increase of IL-12 levels in the plasma. These findings suggest that the Th1 immune response to HIV-1 Tat could be further polarized by these molecules. These results together with those previously reported suggest that pro-GSH molecules could be used to modulate the immune response towards different antigens and may be further exploited for inducing specific Th1 immune responses against other HIV antigens as well as other intracellular pathogens in new Tat-based vaccination protocols.

  5. Whole Genome Deep Sequencing of HIV-1 Reveals the Impact of Early Minor Variants Upon Immune Recognition During Acute Infection

    PubMed Central

    Henn, Matthew R.; Lennon, Niall J.; Power, Karen A.; Macalalad, Alexander R.; Berlin, Aaron M.; Malboeuf, Christine M.; Ryan, Elizabeth M.; Gnerre, Sante; Zody, Michael C.; Erlich, Rachel L.; Green, Lisa M.; Berical, Andrew; Wang, Yaoyu; Casali, Monica; Streeck, Hendrik; Bloom, Allyson K.; Dudek, Tim; Tully, Damien; Newman, Ruchi; Axten, Karen L.; Gladden, Adrianne D.; Battis, Laura; Kemper, Michael; Zeng, Qiandong; Shea, Terrance P.; Gujja, Sharvari; Zedlack, Carmen; Gasser, Olivier; Brander, Christian; Hess, Christoph; Günthard, Huldrych F.; Brumme, Zabrina L.; Brumme, Chanson J.; Bazner, Suzane; Rychert, Jenna; Tinsley, Jake P.; Mayer, Ken H.; Rosenberg, Eric; Pereyra, Florencia; Levin, Joshua Z.; Young, Sarah K.; Jessen, Heiko; Altfeld, Marcus; Birren, Bruce W.; Walker, Bruce D.; Allen, Todd M.

    2012-01-01

    Deep sequencing technologies have the potential to transform the study of highly variable viral pathogens by providing a rapid and cost-effective approach to sensitively characterize rapidly evolving viral quasispecies. Here, we report on a high-throughput whole HIV-1 genome deep sequencing platform that combines 454 pyrosequencing with novel assembly and variant detection algorithms. In one subject we combined these genetic data with detailed immunological analyses to comprehensively evaluate viral evolution and immune escape during the acute phase of HIV-1 infection. The majority of early, low frequency mutations represented viral adaptation to host CD8+ T cell responses, evidence of strong immune selection pressure occurring during the early decline from peak viremia. CD8+ T cell responses capable of recognizing these low frequency escape variants coincided with the selection and evolution of more effective secondary HLA-anchor escape mutations. Frequent, and in some cases rapid, reversion of transmitted mutations was also observed across the viral genome. When located within restricted CD8 epitopes these low frequency reverting mutations were sufficient to prime de novo responses to these epitopes, again illustrating the capacity of the immune response to recognize and respond to low frequency variants. More importantly, rapid viral escape from the most immunodominant CD8+ T cell responses coincided with plateauing of the initial viral load decline in this subject, suggestive of a potential link between maintenance of effective, dominant CD8 responses and the degree of early viremia reduction. We conclude that the early control of HIV-1 replication by immunodominant CD8+ T cell responses may be substantially influenced by rapid, low frequency viral adaptations not detected by conventional sequencing approaches, which warrants further investigation. These data support the critical need for vaccine-induced CD8+ T cell responses to target more highly constrained

  6. Elicitation of broadly reactive antibodies against glycan-modulated neutralizing V3 epitopes of HIV-1 by immune complex vaccines.

    PubMed

    Kumar, Rajnish; Tuen, Michael; Liu, Jianping; Nàdas, Arthur; Pan, Ruimin; Kong, Xiangpeng; Hioe, Catarina E

    2013-11-04

    HIV-1 envelope gp120 is the target for neutralizing antibodies (NAbs) against the virus. Various approaches have been explored to improve immunogenicity of broadly neutralizing epitopes on this antigen with limited success. We previously demonstrated that immunogenicity of gp120 and especially its V3 epitopes was enhanced when gp120 was co-administered as immune-complex vaccines with monoclonal antibodies (mAb) to the CD4-binding site (CD4bs). To define the mechanisms by which immune complexes influence V3 immunogenicity, we compared gp120 complexed with mAbs specific for the C2 region (1006-30), the V2 loop (2158), or the CD4bs (654), and found that the gp120/654 and gp120/2158 complexes elicited anti-V3 NAbs, but the gp120/654 complex was the most effective. gp120 complexed with 654 F(ab')2 was as potent, indicating that V3 immunogenicity is determined by the specificity of the mAb's Fab fragment used to form the complexes. Importantly, the gp120/654 complex not only induced anti-gp120 antibodies (Abs) to higher titers, but also of greater avidity. The Abs were cross-reactive with V3 peptides from most subtype B and some subtype C isolates. Neutralization was detected only against Tier-1 HIV-1 pseudoviruses, while Tier-2 viruses, including the homologous JRFL strain, were not neutralized. However, JRFL produced in the presence of a mannosidase inhibitor was sensitive to anti-V3 NAbs in the immune sera. These results demonstrate that the gp120/654 complex is a potent immunogen for eliciting cross-reactive functional NAbs against V3 epitopes, of which exposure is determined by the specific compositions of glycans shrouding the HIV-1 envelope glycoproteins.

  7. Whole genome deep sequencing of HIV-1 reveals the impact of early minor variants upon immune recognition during acute infection.

    PubMed

    Henn, Matthew R; Boutwell, Christian L; Charlebois, Patrick; Lennon, Niall J; Power, Karen A; Macalalad, Alexander R; Berlin, Aaron M; Malboeuf, Christine M; Ryan, Elizabeth M; Gnerre, Sante; Zody, Michael C; Erlich, Rachel L; Green, Lisa M; Berical, Andrew; Wang, Yaoyu; Casali, Monica; Streeck, Hendrik; Bloom, Allyson K; Dudek, Tim; Tully, Damien; Newman, Ruchi; Axten, Karen L; Gladden, Adrianne D; Battis, Laura; Kemper, Michael; Zeng, Qiandong; Shea, Terrance P; Gujja, Sharvari; Zedlack, Carmen; Gasser, Olivier; Brander, Christian; Hess, Christoph; Günthard, Huldrych F; Brumme, Zabrina L; Brumme, Chanson J; Bazner, Suzane; Rychert, Jenna; Tinsley, Jake P; Mayer, Ken H; Rosenberg, Eric; Pereyra, Florencia; Levin, Joshua Z; Young, Sarah K; Jessen, Heiko; Altfeld, Marcus; Birren, Bruce W; Walker, Bruce D; Allen, Todd M

    2012-01-01

    Deep sequencing technologies have the potential to transform the study of highly variable viral pathogens by providing a rapid and cost-effective approach to sensitively characterize rapidly evolving viral quasispecies. Here, we report on a high-throughput whole HIV-1 genome deep sequencing platform that combines 454 pyrosequencing with novel assembly and variant detection algorithms. In one subject we combined these genetic data with detailed immunological analyses to comprehensively evaluate viral evolution and immune escape during the acute phase of HIV-1 infection. The majority of early, low frequency mutations represented viral adaptation to host CD8+ T cell responses, evidence of strong immune selection pressure occurring during the early decline from peak viremia. CD8+ T cell responses capable of recognizing these low frequency escape variants coincided with the selection and evolution of more effective secondary HLA-anchor escape mutations. Frequent, and in some cases rapid, reversion of transmitted mutations was also observed across the viral genome. When located within restricted CD8 epitopes these low frequency reverting mutations were sufficient to prime de novo responses to these epitopes, again illustrating the capacity of the immune response to recognize and respond to low frequency variants. More importantly, rapid viral escape from the most immunodominant CD8+ T cell responses coincided with plateauing of the initial viral load decline in this subject, suggestive of a potential link between maintenance of effective, dominant CD8 responses and the degree of early viremia reduction. We conclude that the early control of HIV-1 replication by immunodominant CD8+ T cell responses may be substantially influenced by rapid, low frequency viral adaptations not detected by conventional sequencing approaches, which warrants further investigation. These data support the critical need for vaccine-induced CD8+ T cell responses to target more highly constrained

  8. Physical disruption of skin during poxvirus immunization is critical for the generation of highly protective T cell-mediated immunity

    PubMed Central

    Liu, Luzheng; Zhong, Qiong; Tian, Tian; Dubin, Krista; Athale, Shruti K.; Kupper, Thomas S.

    2010-01-01

    Introductory Paragraph Variola major infection (Smallpox) claimed hundreds of millions lives before it was eradicated by a simple vaccination strategy: epicutaneous application of the related orthopoxvirus Vaccinia virus (VACV) to superficially injured skin (skin scarification, s.s.)1. However, the remarkable success of this strategy was attributed to the immunogenicity of VACV rather than the unique vaccine delivery mode. We now demonstrate that VACV immunization via s.s., but not conventional injection routes, is essential to the generation of superior T cell-mediated immune responses that provide complete protection against subsequent challenges, independent of neutralizing antibodies. Skin-resident effector memory T cells (TEM) provide complete protection against cutaneous challenge, while protection against lethal respiratory challenge requires both respiratory mucosal TEM and central memory T cells (TCM). Vaccination with recombinant VACV (rVACV) expressing a tumor antigen was protective against tumor challenge only if delivered via s.s. route, but not by hypodermic injection. Finally, the clinically safer non-replicative Modified Vaccinia Ankara (MVA) also generated far superior protective immunity when delivered via s.s route compared to intramuscular injection used in MVA clinical trials. Thus, delivering rVACV -based vaccines, including MVA vaccines, through physically disrupted epidermis represents a uniquely powerful strategy with clear-cut advantages over conventional vaccination via hypodermic injection. PMID:20081864

  9. Acne vulgaris and acne rosacea as part of immune reconstitution disease in HIV-1 infected patients starting antiretroviral therapy.

    PubMed

    Scott, Christopher; Staughton, Richard C D; Bunker, Christopher J; Asboe, David

    2008-07-01

    Immune reconstitution disease (IRD) has been widely reported following the commencement of antiretrovirals. We report a case series from a cohort of HIV-1-infected patients of whom four developed acne vulgaris and one developed acne rosacea after the initiation of antiretroviral therapy. Acne vulgaris, as part of IRD, has been reported only once in the literature, whereas acne rosacea has not, to our knowledge, previously been described. This serves as a reminder not to overlook dermatological manifestations of disease in patients with HIV infection after starting antiretrovirals.

  10. Efficacy assessment of a cell-mediated immunity HIV-1 vaccine (the Step Study): a double-blind, randomised, placebo-controlled, test-of-concept trial.

    PubMed

    Buchbinder, Susan P; Mehrotra, Devan V; Duerr, Ann; Fitzgerald, Daniel W; Mogg, Robin; Li, David; Gilbert, Peter B; Lama, Javier R; Marmor, Michael; Del Rio, Carlos; McElrath, M Juliana; Casimiro, Danilo R; Gottesdiener, Keith M; Chodakewitz, Jeffrey A; Corey, Lawrence; Robertson, Michael N

    2008-11-29

    Observational data and non-human primate challenge studies suggest that cell-mediated immune responses might provide control of HIV replication. The Step Study directly assessed the efficacy of a cell-mediated immunity vaccine to protect against HIV-1 infection or change in early plasma HIV-1 levels. We undertook a double-blind, phase II, test-of-concept study at 34 sites in North America, the Caribbean, South America, and Australia. We randomly assigned 3000 HIV-1-seronegative participants by computer-generated assignments to receive three injections of MRKAd5 HIV-1 gag/pol/nef vaccine (n=1494) or placebo (n=1506). Randomisation was prestratified by sex, adenovirus type 5 (Ad5) antibody titre at baseline, and study site. Primary objective was a reduction in HIV-1 acquisition rates (tested every 6 months) or a decrease in HIV-1 viral-load setpoint (early plasma HIV-1 RNA measured 3 months after HIV-1 diagnosis). Analyses were per protocol and modified intention to treat. The study was stopped early because it unexpectedly met the prespecified futility boundaries at the first interim analysis. This study is registered with ClinicalTrials.gov, number NCT00095576. In a prespecified interim analysis in participants with baseline Ad5 antibody titre 200 or less, 24 (3%) of 741 vaccine recipients became HIV-1 infected versus 21 (3%) of 762 placebo recipients (hazard ratio [HR] 1.2 [95% CI 0.6-2.2]). All but one infection occurred in men. The corresponding geometric mean plasma HIV-1 RNA was comparable in infected male vaccine and placebo recipients (4.61 vs 4.41 log(10) copies per mL, one tailed p value for potential benefit 0.66). The vaccine elicited interferon-gamma ELISPOT responses in 75% (267) of the 25% random sample of all vaccine recipients (including both low and high Ad5 antibody titres) on whose specimens this testing was done (n=354). In exploratory analyses of all study volunteers, irrespective of baseline Ad5 antibody titre, the HR of HIV-1 infection

  11. Vaccination with gp120-depleted HIV-1 plus immunostimulatory CpG oligodeoxynucleotides in incomplete Freund's adjuvant stimulates cellular and humoral immunity in rhesus macaques.

    PubMed

    Silvera, Peter; Savary, Jay R; Livingston, Virginia; White, Jessica; Manson, Kelledy H; Wyand, Michael H; Salk, Peter L; Moss, Ronald B; Lewis, Mark G

    2004-12-21

    Whole killed human immunodeficiency virus type 1 (HIV-1) immunogens contain the more conserved epitopes of HIV-1 and therefore may provide some utility as potential HIV-1 vaccine candidates. Previous studies have shown that synthetic oligodeoxynucleotides (ODN) containing unmethylated cytosine-guanine (CpG) dinucleotides trigger rapid stimulation of both CD4+ and CD8+ T cells. Here, we investigated whether immunization of rhesus macaques with an inactivated gp120-depleted HIV-1 immunogen, emulsified in incomplete Freund's adjuvant (IFA) together with immunostimulatory CpG-containing ODN (ODN 2006), would elicit HIV-specific cellular and humoral immune responses. High titer anti-p24 antibody levels were induced in all four immunized animals that were sustained 6 weeks after the fifth and final boost at 23 months. These anti-gag antibodies mapped to linear B-cell epitopes within the matrix (MA), capsid (CA), p2, nucleocapsid (NC) and p6 proteins of HIV-1 gag. HIV-specific interferon-gamma-producing CD4+ and CD8+ T-cell responses were measured before and after the fourth and fifth immunizations by both intracellular cytokine (ICC) and ELISPOT techniques; responses were detected in three of the four immunized animals. CD4+ T-cell epitopes appear to map within amino acids 261-290 and 291-320 of p24 CA protein. Immunizations were well tolerated both locally and systemically. Based on these results, further studies of this approach are warranted.

  12. Depot Medroxyprogesterone Acetate Use Is Associated With Elevated Innate Immune Effector Molecules in Cervicovaginal Secretions of HIV-1-Uninfected Women.

    PubMed

    Guthrie, Brandon L; Introini, Andrea; Roxby, Alison C; Choi, Robert Y; Bosire, Rose; Lohman-Payne, Barbara; Hirbod, Taha; Farquhar, Carey; Broliden, Kristina

    2015-05-01

    The effects of sex hormones on the immune defenses of the female genital mucosa and its susceptibility to infections are poorly understood. The injectable hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may increase the risk for HIV-1 acquisition. We assessed the local concentration in the female genital mucosa of cationic polypeptides with reported antiviral activity in relation to DMPA use. HIV-1-uninfected women were recruited from among couples testing for HIV in Nairobi, Kenya. Cervicovaginal secretion samples were collected, and the concentrations of HNP1-3, LL-37, lactoferrin, HBD-2, and SLPI were measured by enzyme-linked immunosorbent assays. Levels of cationic polypeptides in cervicovaginal secretions were compared between women who were not using hormonal contraception and those using DMPA, oral, or implantable contraception. Among 228 women, 165 (72%) reported not using hormonal contraception at enrollment, 41 (18%) used DMPA, 16 (7%) used an oral contraceptive, and 6 (3%) used a contraceptive implant. Compared with nonusers of hormonal contraception, DMPA users had significantly higher mean levels of HNP1-3 (2.38 vs. 2.04 log₁₀ ng/mL; P = 0.024), LL-37 (0.81 vs. 0.40 log10 ng/mL; P = 0.027), and lactoferrin (3.03 vs. 2.60 log₁₀ ng/mL; P = 0.002), whereas SLPI and HBD-2 were similar. Although all analyzed cationic polypeptides have intrinsic antiviral capacity, their interaction and cumulative effect on female genital mucosa susceptibility to infections in vivo has yet to be unraveled. This study suggests a potential mechanism underlying the effect of DMPA on the innate immune defenses, providing a rationale to investigate its effect on HIV-1 acquisition risk.

  13. Poxviruses and the Evolution of Host Range and Virulence

    PubMed Central

    Haller, Sherry L.; Peng, Chen; McFadden, Grant; Rothenburg, Stefan

    2013-01-01

    Poxviruses as a group can infect a large number of animals. However, at the level of individual viruses, even closely related poxviruses display highly diverse host ranges and virulence. For example, variola virus, the causative agent of smallpox, is human-specific and highly virulent only to humans, whereas related cowpox viruses naturally infect a broad spectrum of animals and only cause relatively mild disease in humans. The successful replication of poxviruses depends on their effective manipulation of the host antiviral responses, at the cellular-, tissue- and species-specific levels, which constitutes a molecular basis for differences in poxvirus host range and virulence. A number of poxvirus genes have been identified that possess host range function in experimental settings, and many of these host range genes target specific antiviral host pathways. Herein, we review the biology of poxviruses with a focus on host range, zoonotic infections, virulence, genomics and host range genes as well as the current knowledge about the function of poxvirus host range factors and how their interaction with the host innate immune system contributes to poxvirus host range and virulence. We further discuss the evolution of host range and virulence in poxviruses as well as host switches and potential poxvirus threats for human and animal health. PMID:24161410

  14. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization

    PubMed Central

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S.; Giorgi, Elena E.; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J.; Wagh, Kshitij; Carey, Brittany R.; Gao, Hongmei; Greene, Kelli M.; Tang, Haili; Marais, Jinny C.; Diphoko, Thabo E.; Hraber, Peter; Tumba, Nancy; Moore, Penny L.; Gray, Glenda E.; Kublin, James; McElrath, M. Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L.; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H.; Hahn, Beatrice H.; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C.; Williamson, Carolyn

    2016-01-01

    The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 μg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre

  15. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization.

    PubMed

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S; Giorgi, Elena E; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J; Wagh, Kshitij; Garrity, Jetta; Carey, Brittany R; Gao, Hongmei; Greene, Kelli M; Tang, Haili; Bandawe, Gama P; Marais, Jinny C; Diphoko, Thabo E; Hraber, Peter; Tumba, Nancy; Moore, Penny L; Gray, Glenda E; Kublin, James; McElrath, M Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H; Hahn, Beatrice H; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C; Williamson, Carolyn

    2016-07-01

    The development of biomedical interventions to reduce acquisition of HIV-1 infection remains a global priority, however their potential effectiveness is challenged by very high HIV-1 envelope diversity. Two large prophylactic trials in high incidence, clade C epidemic regions in southern Africa are imminent; passive administration of the monoclonal antibody VRC01, and active immunization with a clade C modified RV144-like vaccines. We have created a large representative panel of C clade viruses to enable assessment of antibody responses to vaccines and natural infection in Southern Africa, and we investigated the genotypic and neutralization properties of recently transmitted clade C viruses to determine how viral diversity impacted antibody recognition. We further explore the implications of these findings for the potential effectiveness of these trials. A panel of 200 HIV-1 Envelope pseudoviruses was constructed from clade C viruses collected within the first 100 days following infection. Viruses collected pre-seroconversion were significantly more resistant to serum neutralization compared to post-seroconversion viruses (p = 0.001). Over 13 years of the study as the epidemic matured, HIV-1 diversified (p = 0.0009) and became more neutralization resistant to monoclonal antibodies VRC01, PG9 and 4E10. When tested at therapeutic levels (10ug/ml), VRC01 only neutralized 80% of viruses in the panel, although it did exhibit potent neutralization activity against sensitive viruses (IC50 titres of 0.42 μg/ml). The Gp120 amino acid similarity between the clade C panel and candidate C-clade vaccine protein boosts (Ce1086 and TV1) was 77%, which is 8% more distant than between CRF01_AE viruses and the RV144 CRF01_AE immunogen. Furthermore, two vaccine signature sites, K169 in V2 and I307 in V3, associated with reduced infection risk in RV144, occurred less frequently in clade C panel viruses than in CRF01_AE viruses from Thailand. Increased resistance of pre

  16. Comparative clonal analysis of human immunodeficiency virus type 1 (HIV- 1)-specific CD4+ and CD8+ cytolytic T lymphocytes isolated from seronegative humans immunized with candidate HIV-1 vaccines

    PubMed Central

    1992-01-01

    The lysis of infected host cells by virus-specific cytolytic T lymphocytes (CTL) is an important factor in host resistance to viral infection. An optimal vaccine against human immunodeficiency virus type 1 (HIV-1) would elicit virus-specific CTL as well as neutralizing antibodies. The induction by a vaccine of HIV-1-specific CD8+ CTL in humans has not been previously reported. In this study, CTL responses were evaluated in HIV-1-seronegative human volunteers participating in a phase I acquired immune deficiency syndrome (AIDS) vaccine trial involving a novel vaccine regimen. Volunteers received an initial immunization with a live recombinant vaccinia virus vector carrying the HIV-1 env gene and a subsequent boost with purified env protein. An exceptionally strong env-specific CTL response was detected in one of two vaccine recipients, while modest but significant env-specific CTL activity was present in the second vaccinee. Cloning of the responding CTL gave both CD4+ and CD8+ env-specific CTL clones, permitting a detailed comparison of critical functional properties of these two types of CTL. In particular, the potential antiviral effects of these CTL were evaluated in an in vitro system involving HIV-1 infection of cultures of normal autologous CD4+ lymphoblasts. At extremely low effector-to-target ratios, vaccine-induced CD8+ CTL clones lysed productively infected cells present within these cultures. When tested for lytic activity against target cells expressing the HIV-1 env gene, CD8+ CTL were 3-10-fold more active on a per cell basis than CD4+ CTL. However, when tested against autologous CD4+ lymphoblasts acutely infected with HIV-1, CD4+ clones lysed a much higher fraction of the target cell population than did CD8+ CTL. CD4+ CTL were shown to recognize not only the infected cells within these acutely infected cultures but also noninfected CD4+ T cells that had passively taken up gp120 shed from infected cells and/or free virions. These results were

  17. An Effective Vaccination Approach Augments anti-HIV Systemic and Vaginal Immunity in Mice with Decreased HIV-1 Susceptible α4β7high CD4+ T Cells

    PubMed Central

    Zhu, Wei; Shi, Guoping; Tang, Haijun; Lewis, Dorothy E; Song, Xiao-Tong

    2013-01-01

    HIV-1 preferentially infects activated CD4+ T cells expressing α4β7 integrin and conventional vaccination approaches non-selectively induce immune responses including α4β7high CD4+ T cells, suggesting that current candidate AIDS vaccines may produce more target cells for HIV-1 and paradoxically enhance HIV-1 infection. Thus it remains a challenge to selectively induce robust anti-HIV immunity without the unwanted HIV-1 susceptible α4β7high CD4+ T cells. Here we describe a vaccination strategy that targets ALDH1a2, a retinoic acid producing enzyme in dendritic cells (DCs). Silencing ALDH1a2 in DCs enhanced the maturation and production of proinflammatory cytokines of DCs and promoted Th1/Th2 differentiation while suppressing Treg. ALDH1a2-silenced DCs effectively downregulated the expression of guthoming receptors α4β7 and CCR9 on activated T and B lymphocytes. Consequently, intranasal immunization of a lentiviral vaccine encoding ALDH1a2 shRNA and HIV-1 gp140 redirected gp140-specific mucosal T cell and antibody responses from the gut to the vaginal tract, while dramatically enhancing systemic gp140-specific immune responses. We further demonstrated that silencing ALDH1a2 in human DCs resulted in downregulation of β7 expression on activated autologous CD4+ T cells. Hence this study provides a unique and effective strategy to induce α4β7low anti-HIV immune responses. PMID:23157585

  18. An effective vaccination approach augments anti-HIV systemic and vaginal immunity in mice with decreased HIV-1 susceptible α4β7high CD4+ T cells.

    PubMed

    Zhu, Wei; Shi, Guoping; Tang, Haijun; Lewis, Dorothy E; Song, Xiao-Tong

    2013-01-01

    HIV-1 preferentially infects activated CD4(+) T cells expressing α4β7 integrin and conventional vaccination approaches non-selectively induce immune responses including α4β7(high) CD4(+) T cells, suggesting that current candidate AIDS vaccines may produce more target cells for HIV-1 and paradoxically enhance HIV-1 infection. Thus it remains a challenge to selectively induce robust anti-HIV immunity without the unwanted HIV-1 susceptible α4β77(high) CD4(+)+ T cells. Here we describe a vaccination strategy that targets ALDH1a2, a retinoic acid producing enzyme in dendritic cells (DCs). Silencing ALDH1a2 in DCs enhanced the maturation and production of proinflammatory cytokines of DCs and promoted Th1/Th2 differentiation while suppressing Treg. ALDH1a2-silenced DCs effectively downregulated the expression of guthoming receptors α4β77 and CCR9 on activated T and B lymphocytes. Consequently, intranasal immunization of a lentiviral vaccine encoding ALDH1a2 shRNA and HIV-1 gp140 redirected gp140-specific mucosal T cell and antibody responses from the gut to the vaginal tract, while dramatically enhancing systemic gp140-specific immune responses. We further demonstrated that silencing ALDH1a2 in human DCs resulted in downregulation of β7 expression on activated autologous CD4(+) T cells. Hence this study provides a unique and effective strategy to induce α4β7(low) anti-HIV immune responses.

  19. Evidence for the innate immune response as a correlate of protection in human immunodeficiency virus (HIV)-1 highly exposed seronegative subjects (HESN)

    PubMed Central

    Tomescu, C; Abdulhaqq, S; Montaner, L J

    2011-01-01

    The description of highly exposed individuals who remain seronegative (HESN) despite repeated exposure to human immunodeficiency virus (HIV)-1 has heightened interest in identifying potential mechanisms of HIV-1 resistance. HIV-specific humoral and T cell-mediated responses have been identified routinely in HESN subjects, although it remains unknown if these responses are a definitive cause of protection or merely a marker for exposure. Approximately half of HESN lack any detectible HIV-specific adaptive immune responses, suggesting that other mechanisms of protection from HIV-1 infection also probably exist. In support of the innate immune response as a mechanism of resistance, increased natural killer (NK) cell activity has been correlated with protection from infection in several high-risk cohorts of HESN subjects, including intravenous drug users, HIV-1 discordant couples and perinatally exposed infants. Inheritance of protective NK KIR3DL1high and KIR3DS1 receptor alleles have also been observed to be over-represented in a high-risk cohort of HESN intravenous drug users and HESN partners of HIV-1-infected subjects. Other intrinsic mechanisms of innate immune protection correlated with resistance in HESN subjects include heightened dendritic cell responses and increased secretion of anti-viral factors such as β-chemokines, small anti-viral factors and defensins. This review will highlight the most current evidence in HESN subjects supporting the role of epithelial microenvironment and the innate immune system in sustaining resistance against HIV-1 infection. We will argue that as a front-line defence the innate immune response determines the threshold of infectivity that HIV-1 must overcome to establish a productive infection. PMID:21413945

  20. [A novel immunization strategy to induce strong humoral responses against HIV-1 using combined DNA, recombinant vaccinia virus and protein vaccines].

    PubMed

    Liu, Chang; Wang, Shu-hui; Ren, Li; Hao, Yan-ling; Zhang, Qi-cheng; Liu, Ying

    2014-11-01

    To optimize the immunization strategy against HIV-1, a DNA vaccine was combined with a recombinant vaccinia virus (rTV) vaccine and a protein vaccine. Immune responses against HIV-1 were detected in 30 female guinea pigs divided into six groups. Three groups of guinea pigs were primed with HIV-1 DNA vaccine three times, boosted with rTV at week 14, and then boosted with gp140 protein at intervals of 4, 8 or 12 weeks. Simultaneously, the other three groups of animals were primed with rTV vaccine once, and then boosted with gp140 after 4, 8 or 12 weeks. The HIV-1 specific binding antibody and neutralizing antibody, in addition to the relative affinity of these antibodies, were detected at different time points after the final administration of vaccine in each group. The DNA-rTV-gp140 immune regimen induced higher titers and affinity levels of HIV-1 gp120/gp140 antibodies and stronger V1V2-gp70 antibodies than the rTV-gp140 regimen. In the guinea pigs that underwent the DNA-rTV-gp140 regimen, the highest V1V2-gp70 antibody was induced in the 12-week-interval group. However, the avidity of antibodies was improved in the 4-week-interval group. Using the rTV-gp140 immunization strategy, guinea pigs boosted at 8 or 12 weeks after rTV priming elicited stronger humoral responses than those boosted at 4 weeks after priming. In conclusion, this study shows that the immunization strategy of HIV-1 DNA vaccine priming, followed by rTV and protein vaccine boosting, could strengthen the humoral response against HIV-1. Longer intervals were better to induce V1V2-gp70-specific antibodies, while shorter intervals were more beneficial to enhance the avidity of antibodies.

  1. Cross-clade neutralizing antibodies against HIV-1 induced in rabbits by focusing the immune response on a neutralizing epitope

    SciTech Connect

    Zolla-Pazner, Susan; Cohen, Sandra; Pinter, Abraham; Krachmarov, Chavdar; Wrin, Terri; Wang Shixia; Lu Shan

    2009-09-15

    Studies were performed to induce cross-clade neutralizing antibodies (Abs) by testing various combinations of prime and boost constructs that focus the immune response on structurally-conserved epitopes in the V3 loop of HIV-1 gp120. Rabbits were immunized with gp120 DNA containing a V3 loop characterized by the GPGR motif at its tip, and/or with gp120 DNA with a V3 loop carrying the GPGQ motif. Priming was followed by boosts with V3-fusion proteins (V3-FPs) carrying the V3 sequence from a subtype B virus (GPGR motif), and/or with V3 sequences from subtypes A and C (GPGQ motif). The broadest and most consistent neutralizing responses were generated when using a clade C gp120 DNA prime and with the V3{sub B}-FP boost. Immune sera displayed neutralizing activity in three assays against pseudoviruses and primary isolates from subtypes A, AG, B, C, and D. Polyclonal Abs in the immune rabbit sera neutralized viruses that were not neutralized by pools of human anti-V3 monoclonal Abs. Greater than 80% of the neutralizing Abs were specific for V3, showing that the immune response could be focused on a neutralizing epitope and that vaccine-induced anti-V3 Abs have cross-clade neutralizing activity.

  2. Intranasal immunization of young mice with a multigene HIV-1 vaccine in combination with the N3 adjuvant induces mucosal and systemic immune responses.

    PubMed

    Bråve, Andreas; Hallengärd, David; Schröder, Ulf; Blomberg, Pontus; Wahren, Britta; Hinkula, Jorma

    2008-09-19

    One of the major challenges for the development of an HIV vaccine is to induce potent virus-specific immune responses at the mucosal surfaces where transmission of virus occurs. Intranasal delivery of classical vaccines has been shown to induce good mucosal antibody responses, but so far for genetic vaccines the success has been limited. This study shows that young individuals are sensitive to nasal immunization with a genetic vaccine delivered in a formulation of a lipid adjuvant, the Eurocine N3. Intranasal delivery of a multiclade/multigene HIV-1 genetic vaccine gave rise to vaginal and rectal IgA responses as well as systemic humoral and cellular responses. As electroporation might become the preferred means of delivering genetic vaccines for systemic HIV immunity, nasal delivery by droplet formulation in a lipid adjuvant might become a means of priming or boosting the mucosal immunity.

  3. Adenoviral vectors elicit humoral immunity against variable loop 2 of clade C HIV-1 gp120 via “Antigen Capsid-Incorporation” strategy

    PubMed Central

    Gu, Linlin; Krendelchtchikova, Valentina; Krendelchtchikov, Alexandre; Farrow, Anitra L.; Derdeyn, Cynthia A.; Matthews, Qiana L.

    2016-01-01

    Adenoviral (Ad) vectors in combination with the “Antigen Capsid-Incorporation” strategy have been applied in developing HIV-1 vaccines, due to the vectors’ abilities in incorporating and inducing immunity of capsid-incorporated antigens. Variable loop 2 (V2)-specific antibodies were suggested in the RV144 trial to correlate with reduced HIV-1 acquisition, which highlights the importance of developing novel HIV-1 vaccines by targeting the V2 loop. Therefore, the V2 loop of HIV-1 has been incorporated into the Ad capsid protein. We generated adenovirus serotype 5 (Ad5) vectors displaying variable loop 2 (V2) of HIV-1 gp120, with the “Antigen Capsid-Incorporation” strategy. To assess the incorporation capabilities on hexon hypervariable region1 (HVR1) and protein IX (pIX), 20aa or full length (43aa) of V2 and V1V2 (67aa) were incorporated, respectively. Immunizations with the recombinant vectors significantly generated antibodies against both linear and discontinuous V2 epitopes. The immunizations generated durable humoral immunity against V2. This study will lead to more stringent development of various serotypes of adenovirus-vectored V2 vaccine candidates, based on breakthroughs regarding the immunogenicity of V2. PMID:26499044

  4. A Retrospective Cohort Study of Lesion Distribution of HIV-1 Infection Patients With Cryptococcal Meningoencephalitis on MRI: Correlation With Immunity and Immune Reconstitution.

    PubMed

    Xia, Shuang; Li, Xueqin; Shi, Yanbin; Liu, Jinxin; Zhang, Mengjie; Gu, Tenghui; Pan, Shinong; Song, Liucun; Xu, Jinsheng; Sun, Yan; Zhao, Qingxia; Lu, Zhiyan; Lu, Puxuan; Li, Hongjun

    2016-02-01

    The objective of this paper is to correlate the MRI distribution of cryptococcal meningoencephalitis in HIV-1 infection patients with CD4 T cell count and immune reconstitution effect.A large retrospective cohort study of HIV patients from multi-HIV centers in China was studied to demonstrate the MRI distribution of cryptococcal meningoencephalitis and its correlation with the different immune status.The consecutive clinical and neuroimaging data of 55 HIV-1-infected patients with cryptococcal meningoencephalitis collected at multi-HIV centers in China during the years of 2011 to 2014 was retrospectively analyzed. The enrolled patients were divided into 2 groups based on the distribution of lesions. One group of patients had their lesions at the central brain (group 1, n = 34) and the other group of patients had their lesions at the superficial brain (group 2, n = 21). We explored their MRI characterization of brain. In addition, we also compared their CD4 T cell counts and immune reconstitution effects between the 2 groups based on the imaging findings.No statistical difference was found in terms of age and gender between the 2 groups. The medians of CD4 T cell counts were 11.67 cells/mm (3.00-52.00 cells/mm) in group 1 and 42.00 cells/mm (10.00-252.00 cells/mm) in group 2. Statistical difference of CD4 T cell count was found between the 2 groups (P = 0.023). Thirteen patients in group 1 (13/34) and 12 patients in group 2 (12/21) received highly active antiretroviral treatment (HAART). Patients of group 2 received HAART therapy more frequently than patients of group 1 (P = 0.021).Central and superficial brain lesions detected by MR imaging in HIV-1-infected patients with cryptococcal meningoencephalitis are in correlation with the host immunity and HAART therapy.

  5. Plasma levels of soluble CD27: a simple marker to monitor immune activation during potent antiretroviral therapy in HIV-1-infected subjects

    PubMed Central

    DE MILITO, A; ALEMAN, S; MARENZI, R; SÖNNERBORG, A; FUCHS, D; ZAZZI, M; CHIODI, F

    2002-01-01

    Plasma levels of soluble CD27 (sCD27) are elevated in diseases characterized by T cell activation and are used as a marker of immune activation. We assessed the usefulness of determining plasma sCD27 as a marker for monitoring immune activation in HIV-1-infected patients treated with highly active antiretroviral therapy (HAART). A first cross-sectional examination of 68 HIV-1-infected and 18 normal subjects showed high levels of sCD27 in HIV-1 infection; plasma sCD27 was correlated to HIV-1 viraemia and inversely correlated to CD4+ T cell count. Twenty-six HIV-1-infected patients undergoing HAART were studied at baseline and after 6, 12, 18 and 24 months of therapy. Seven additional patients under HAART were analysed at baseline, during and after interruption of therapy. In the total population, HAART induced a significant and progressive reduction, but not a normalization, of plasma levels of sCD27 after 24 months. A full normalization of plasma sCD27 was observed in the virological responders (undetectable HIV-1 RNA at months 18 and 24) and also in patients with moderate immunodeficiency at baseline (CD4+ T cell count >200 cells/mm3). Changes in plasma neopterin paralleled the changes in sCD27 but only baseline sCD27 levels were predictive of a greater increase in CD4+ T cell count during the follow-up. Discontinuation of therapy resulted in a rapid increase of sCD27 plasma levels associated with viraemia rebound and drop in CD4+ T cell count. Our findings suggest that plasma sCD27 may represent an alternative and simple marker to monitor immune activation during potent antiretroviral therapy. HIV-1-induced immune activation can be normalized by HAART in successfully treated patients where the disease is not advanced. PMID:11966765

  6. The importance of becoming double-stranded: Innate immunity and the kinetic model of HIV-1 central plus strand synthesis

    SciTech Connect

    Poeschla, Eric

    2013-06-20

    Central initiation of plus strand synthesis is a conserved feature of lentiviruses and certain other retroelements. This complication of the standard reverse transcription mechanism produces a transient “central DNA flap” in the viral cDNA, which has been proposed to mediate its subsequent nuclear import. This model has assumed that the important feature is the flapped DNA structure itself rather than the process that produces it. Recently, an alternative kinetic model was proposed. It posits that central plus strand synthesis functions to accelerate conversion to the double-stranded state, thereby helping HIV-1 to evade single-strand DNA-targeting antiviral restrictions such as APOBEC3 proteins, and perhaps to avoid innate immune sensor mechanisms. The model is consistent with evidence that lentiviruses must often synthesize their cDNAs when dNTP concentrations are limiting and with data linking reverse transcription and uncoating. There may be additional kinetic advantages for the artificial genomes of lentiviral gene therapy vectors. - Highlights: • Two main functional models for HIV central plus strand synthesis have been proposed. • In one, a transient central DNA flap in the viral cDNA mediates HIV-1 nuclear import. • In the other, multiple kinetic consequences are emphasized. • One is defense against APOBEC3G, which deaminates single-stranded DNA. • Future questions pertain to antiviral restriction, uncoating and nuclear import.

  7. HIV-1 Adaptation to Antigen Processing Results in Population-Level Immune Evasion and Affects Subtype Diversification

    PubMed Central

    Tenzer, Stefan; Crawford, Hayley; Pymm, Phillip; Gifford, Robert; Sreenu, Vattipally B.; Weimershaus, Mirjana; de Oliveira, Tulio; Burgevin, Anne; Gerstoft, Jan; Akkad, Nadja; Lunn, Daniel; Fugger, Lars; Bell, John; Schild, Hansjörg; van Endert, Peter; Iversen, Astrid K.N.

    2014-01-01

    Summary The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8+ T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when these regions encode epitopes presented by ∼30 more common HLA variants. By combining epitope processing and computational analyses of the two HIV subtypes responsible for ∼60% of worldwide infections, we identified a hitherto unrecognized adaptation to the antigen-processing machinery through substitutions at subtype-specific motifs. Multiple HLA variants presenting epitopes situated next to a given subtype-specific motif drive selection at this subtype-specific position, and epitope abundances correlate inversely with the HLA frequency distribution in affected populations. This adaptation reflects the sum of intrapatient adaptations, is predictable, facilitates viral subtype diversification, and increases global HIV diversity. Because low epitope abundance is associated with infrequent and weak T cell responses, this most likely results in both population-level immune evasion and inadequate responses in most people vaccinated with natural HIV-1 sequence constructs. Our results suggest that artificial sequence modifications at subtype-specific positions in vitro could refocus and reverse the poor immunogenicity of HIV proteins. PMID:24726370

  8. HIV-1 Cross-reactive Primary Virus Neutralizing Antibody Response Elicited by Immunization in Non-human Primate.

    PubMed

    Wang, Yimeng; O'Dell, Sijy; Turner, Hannah L; Chiang, Chi-I; Lei, Lin; Guenaga, Javier; Wilson, Richard; Martinez-Murillo, Paola; Doria-Rose, Nicole; Ward, Andrew B; Mascola, John R; Wyatt, Richard T; Karlsson Hedestam, Gunilla B; Li, Yuxing

    2017-08-23

    Elicitation of broadly neutralizing antibody (bNAb) responses is a major goal for the development of an HIV-1 vaccine. Current HIV-1 envelope glycoprotein (Env) vaccine candidates predominantly elicit tier 1 and/or autologous tier 2 virus neutralizing antibody (NAb) responses, as well as weak and/or sporadic cross-reactive tier 2 virus NAb responses with unknown specificity. To delineate the specificity of vaccine-elicited cross-reactive tier 2 virus NAb responses, we performed single memory B cell sorting from the peripheral blood of a rhesus macaque immunized with YU2gp140-F trimers in adjuvant, using JR-FL SOSIP.664, a native Env trimer mimetic as sorting probe to isolate monoclonal Abs (MAbs). We found striking genetic and functional convergence of the SOSIP-sorted Ig repertoire, with pre-dominant VH4 or VH5 gene family usage and Env V3-specificity. Of these vaccine-elicited V3-specific mAbs, nearly 20% (6/33) displayed cross-reactive tier 2 virus neutralization, which recapitulated the serum neutralization capacity. Substantial similarities in binding specificity, neutralization breadth and potency, and sequence/structural homology were observed between selected macaque cross-reactive V3 NAbs elicited by vaccination and prototypic V3 NAbs derived from natural infections in humans, highlighting the convergence of this subset of primate V3-specific B cell repertories. Our study demonstrated that cross-reactive primary virus neutralizing B cell lineages could be elicited by vaccination as detected using a standardized panel of tier 2 viruses. Whether these lineages could be expanded to acquire increased breadth and potency of neutralization merits further investigation.IMPORTANCE Elicitation of antibody responses capable of neutralizing diverse HIV-1 primary virus isolates (designated as broadly neutralizing antibodies, bNAbs) remains a high priority for the vaccine field. bNAb responses were so far only observed in response to natural infection and only in a

  9. The effects of CpG-ODNs and Chitosan adjuvants on the elicitation of immune responses induced by the HIV-1-Tat-based candidate vaccines in mice.

    PubMed

    Alipour, Samira; Mahdavi, Atiyeh; Abdoli, Asghar

    2017-03-01

    HIV1-Tat-based vaccines could elicit broad, durable and neutralizing immune responses and are considered as potential AIDS vaccines. The present study aims to formulate CpG-ODNs adjuvant and Chitosan with Tat protein to enhance the immunogenicity of HIV-1-Tat-based candidate vaccines and to investigate their efficacies in mice. To this end, we added CpG-ODNs, Chitosan and Alum as adjuvants to the Tat-based candidate vaccine formulations. Then, we compared frequency and magnitude of both humoral and cellular immune responses from mice immunized with the adjuvant-formulated Tat candidate vaccines against those obtained from mice immunized with recombinant Tat protein alone. Mice were subcutaneously immunized three times at 2-week intervals with the candidate vaccines. Measurements of anti-Tat immune responses showed that all vaccinated groups had a good immunity compared to the control groups and developed high levels of both humoral and cellular responses. However, immunized mice with CpG-ODNs, and Chitosan-adjuvanted Tat vaccines elicited stronger T-cell responses (both humoral and cellular immunity) compared to the others. These data suggest that co-administration of recombinant Tat protein with CpG-ODNs and Chitosan may serve as a potential formulation for enhancing of the Tat vaccine-induced immunity and might have effects on shaping Th polarization induced by HIV1-Tat protein vaccines. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Allo-immunization elicits CCR5 antibodies, SDF-1 chemokines, and CD8-suppressor factors that inhibit transmission of R5 and X4 HIV-1 in women.

    PubMed

    Wang, Y; Underwood, J; Vaughan, R; Harmer, A; Doyle, C; Lehner, T

    2002-09-01

    Studies in humans suggest that allo-immunization induces CC-chemokines, CD8-suppressor factors (SF) and anti-HIV immunity. Here we report that allo-immunization with unmatched leucocytes from partners of women with recurrent spontaneous abortion elicits specific antibodies to the CCR5 receptor. Such antibodies inhibit replication of M-tropic HIV-1 (R5) and MIP-1beta-mediated chemotaxis. These CCR5 antibodies were also found in the sera of multiparous women that were naturally immunized by semi-allogeneic fetal antigens. The specificity of these antibodies was demonstrated by adsorption with CCR5 transfected HEK-293 cells, a baculovirus CCR5 preparation and a peptide of the 2nd extra-cellular loop of CCR5. Allo-immunization also stimulated increased concentrations of the CXC chemokine, SDF-1alpha and CD8-SF that inhibit T-tropic HIV-1 (X4) replication. We suggest that allo- immunization may elicit (a) CC chemokines, CCR5 antibodies and CD8-SF that inhibit M-tropic HIV-1 infection and (b) the CXC chemokine SDF-1alpha and CD8-SF that inhibit T-tropic HIV-1 infection.

  11. HIV-1 Treated Patients with Undetectable Viral Loads have Lower Levels of Innate Immune Responses via Cytosolic DNA Sensing Systems Compared with Healthy Uninfected Controls.

    PubMed

    Swaminathan, Sanjay; Sui, Hongyan; Adelsberger, Joseph W; Chen, Qian; Sneller, Michael; Migueles, Stephen A; Kottilil, Shyamasundaran; Ober, Alexander; Jones, Sara; Rehm, Catherine A; Lane, H Clifford; Imamichi, Tomozumi

    2014-06-01

    After DNA or RNA virus infection, cytosolic foreign DNA or RNA derived from the infecting viruses is recognized by intracellular pathogen recognition receptors (PRRs) and induces activation of the innate immune system. Transfection of DNA has been used as an experimental model for DNA virus-mediated innate responses. We have previously reported that DNA transfection preferentially induces Type-III IFN (IFN-λ1) rather than Type-I IFN (IFN-β). In this study, we compared the DNA-mediated immune response between healthy controls and HIV-1 infected patients with undetectable viral loads and assessed potential innate immune responses in these patients. The study consisted of 50 HIV-1 negative healthy donors, 46 patients on combination antiretroviral therapy with HIV-1 viral loads <50 copies/ml and 7 long term non-progressors (LTNPs). PBMCs were isolated from whole blood using Ficoll-Paque. DNA transfection was performed using Lipofectamine 2000. After 22 hours incubation, total cellular RNA was extracted and real time RT-PCR was performed to determine gene expression level of IFN-λ1, IFN-β and RANTES. Gene induction was compared by fold change. Baseline levels of endogenous gene expression of IFN-λ1, IFN-β and RANTES in HIV-1 patients were higher than in controls. Following DNA transfection, both HIV infected patients and healthy controls induced gene induction, however, the induction in HIV-1 patients was at a significantly lower level compared to uninfected controls. HIV-1 treated patients with undetectable viral loads have lower levels of innate immune responses via cytosolic DNA sensing systems. This may be caused by persistent immune activation.

  12. Cellular immune responses in human immunodeficiency virus (HIV)-1-infected children: is immune restoration by highly active anti-retroviral therapy comparable to non-progression?

    PubMed

    Hainaut, M; Verscheure, V; Ducarme, M; Schandené, L; Levy, J; Mascart, F

    2011-07-01

    The objective of this study was to investigate whether the restored immune functions of vertically human immunodeficiency virus (HIV)-infected children who were severely immunodeficient before the initiation of highly active anti-retroviral therapy (HAART) are comparable to those of untreated slow progressors. We therefore assessed T cell proliferation and cytokine [interferon (IFN)-γ, interleukin (IL)-5 and IL-13] secretions after mitogen, recall antigens and HIV-1-specific stimulation in 12 untreated slow progressors, 16 untreated progressors and 18 treated patients. Treated children were profoundly immunodeficient before the initiation of HAART and had long-lasting suppression of viral replication on treatment. We demonstrated that slow progressors are characterized not only by the preservation of HIV-1-specific lymphoproliferative responses but also by the fact that these responses are clearly T helper type 1 (Th1)-polarized. Children on HAART had proliferative responses to HIV-1 p24 antigen, purified protein derivative (PPD) and tetanus antigen similar to slow progressors and higher than those of progressors. However, in contrast to slow progressors, most treated children exhibited a release of Th2 cytokines accompanying the IFN-γ secretion in response to the HIV-1 p24 antigen. Moreover, despite higher proliferative responses to phytohaemagglutinin (PHA) than the two groups of untreated children, treated children had lower levels of IFN-γ secretion in response to PHA than slow progressors. These data show that in severely immunodeficient vertically HIV-infected children, a long-lasting HAART allows recovering lymphoproliferative responses similar to untreated slow progressors. However, alterations in IFN-γ secretion in response to the mitogen PHA persisted, and their cytokine release after HIV-specific stimulation was biased towards a Th2 response. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.

  13. Soluble multi-trimeric TNF superfamily ligand adjuvants enhance immune responses to a HIV-1 Gag DNA vaccine.

    PubMed

    Kanagavelu, Saravana K; Snarsky, Victoria; Termini, James M; Gupta, Sachin; Barzee, Suzanne; Wright, Jacqueline A; Khan, Wasif N; Kornbluth, Richard S; Stone, Geoffrey W

    2012-01-17

    DNA vaccines remain an important component of HIV vaccination strategies, typically as part of a prime/boost vaccination strategy with viral vector or protein boost. A number of DNA prime/viral vector boost vaccines are currently being evaluated for both preclinical studies and in Phase I and Phase II clinical trials. These vaccines would benefit from molecular adjuvants that increase correlates of immunity during the DNA prime. While HIV vaccine immune correlates are still not well defined, there are a number of immune assays that have been shown to correlate with protection from viral challenge including CD8+ T cell avidity, antigen-specific proliferation, and polyfunctional cytokine secretion. Recombinant DNA vaccine adjuvants composed of a fusion between Surfactant Protein D (SP-D) and either CD40 Ligand (CD40L) or GITR Ligand (GITRL) were previously shown to enhance HIV-1 Gag DNA vaccines. Here we show that similar fusion constructs composed of the TNF superfamily ligands (TNFSFL) 4-1BBL, OX40L, RANKL, LIGHT, CD70, and BAFF can also enhanced immune responses to a HIV-1 Gag DNA vaccine. BALB/c mice were vaccinated intramuscularly with plasmids expressing secreted Gag and SP-D-TNFSFL fusions. Initially, mice were analyzed 2 weeks or 7 weeks following vaccination to evaluate the relative efficacy of each SP-D-TNFSFL construct. All SP-D-TNFSFL constructs enhanced at least one Gag-specific immune response compared to the parent vaccine. Importantly, the constructs SP-D-4-1BBL, SP-D-OX40L, and SP-D-LIGHT enhanced CD8+ T cell avidity and CD8+/CD4+ T cell proliferation 7 weeks post vaccination. These avidity and proliferation data suggest that 4-1BBL, OX40L, and LIGHT fusion constructs may be particularly effective as vaccine adjuvants. Constructs SP-D-OX40L, SP-D-LIGHT, and SP-D-BAFF enhanced Gag-specific IL-2 secretion in memory T cells, suggesting these adjuvants can increase the number of self-renewing Gag-specific CD8+ and/or CD4+ T cells. Finally adjuvants SP

  14. Durable cytotoxic immune responses against gp120 elicited by recombinant SV40 vectors encoding HIV-1 gp120 +/- IL-15.

    PubMed

    McKee, Hayley J; T'sao, Patricia Y; Vera, Maria; Fortes, Puri; Strayer, David S

    2004-08-23

    BACKGROUND: A vaccine that elicits durable, powerful anti-HIV immunity remains an elusive goal. In these studies we tested whether multiple treatments with viral vector-delivered HIV envelope antigen (gp120), with and without IL-15, could help to approach that goal. For this purpose, we used recombinant Tag-deleted SV40-derived vectors (rSV40s), since they do not elicit neutralizing antibody responses, and so can be given multiply without loss of transduction efficiency. METHODS: SV(gp120) carried the coding sequences for HIV-1NL4-3 Env, and SV(mIL-15) carried the cDNA for mouse IL-15. Singly, and in combination, these two vectors were given monthly to BALB/cJ mice. Cytotoxic immunity and cytotoxic memory were tested in direct cytotoxicity assays using unselected effector cells. Antibody vs. gp120 was measured in a binding assay. In both cases, targets were P815 cells that were stably transfected with gp120. RESULTS: Multiple injections of SV(gp120) elicited powerful anti-gp120 cytolytic activity (>70% specific lysis) by unselected spleen cells. Cells from multiply-immunized mice that were rested 1 year after their last injections still showed >60% gp120-specific lysis. Anti-gp120 antibody was first detected after 2 monthly injections of SV(gp120) and remained elevated thereafter. Adding SV(mIL-15) to the immunization regimen dramatically accelerated the development of memory cytolytic responses, with >/= 50% specific lysis seen 1 month after two treatments. IL-15 did not alter the development of antibody responses. CONCLUSIONS: Thus, rSV40s encoding antigens and immunostimulatory cytokines may be useful tools for priming and/or boosting immune responses against HIV.

  15. Dynamics of a Delayed HIV-1 Infection Model with Saturation Incidence Rate and CTL Immune Response

    NASA Astrophysics Data System (ADS)

    Guo, Ting; Liu, Haihong; Xu, Chenglin; Yan, Fang

    2016-12-01

    In this paper, we investigate the dynamics of a five-dimensional virus model incorporating saturation incidence rate, CTL immune response and three time delays which represent the latent period, virus production period and immune response delay, respectively. We begin this model by proving the positivity and boundedness of the solutions. Our model admits three possible equilibrium solutions, namely the infection-free equilibrium E0, the infectious equilibrium without immune response E1 and the infectious equilibrium with immune response E2. Moreover, by analyzing corresponding characteristic equations, the local stability of each of the feasible equilibria and the existence of Hopf bifurcation at the equilibrium point E2 are established, respectively. Further, by using fluctuation lemma and suitable Lyapunov functionals, it is shown that E0 is globally asymptotically stable when the basic reproductive numbers for viral infection R0 is less than unity. When the basic reproductive numbers for immune response R1 is less than unity and R0 is greater than unity, the equilibrium point E1 is globally asymptotically stable. Finally, some numerical simulations are carried out for illustrating the theoretical results.

  16. Incomplete immune reconstitution despite virologic suppression in HIV-1 infected children and adolescents.

    PubMed

    Krogstad, Paul; Patel, Kunjal; Karalius, Brad; Hazra, Rohan; Abzug, Mark J; Oleske, James; Seage, George R; Williams, Paige L; Borkowsky, William; Wiznia, Andrew; Pinto, Jorge; Van Dyke, Russell B

    2015-03-27

    Some perinatally infected children do not regain normal CD4(+) T-cell counts despite suppression of HIV-1 plasma viremia by antiretroviral therapy (ART). The frequency, severity and significance of these discordant treatment responses remain unclear. We examined the persistence of CD4(+) lymphocytopenia despite virologic suppression in 933 children (≥ 5 years of age) in the USA, Latin America and the Caribbean. CD4(+) T-cell trajectories were examined and Kaplan-Meier methods used to estimate median time to CD4(+) T-cell count at least 500 cells/μl. After 1 year of virologic suppression, most (99%) children achieved a CD4(+) T-cell count of at least 200 cells/μl, but CD4(+) T-cell counts remained below 500 cells/μl after 1 and 2 years of virologic suppression in 14 and 8% of children, respectively. Median times to first CD4(+) T-cell count at least 500 cells/μl were 1.29, 0.78 and 0.46 years for children with less than 200, 200-349 and 350-499 cells/μl at the start of virologic suppression. New AIDS-defining events occurred in nine children, including four in the first 6 months of virologic suppression. Other infectious and HIV-related diagnoses occurred more frequently and across a wide range of CD4(+) cell counts. ART improved CD4(+) cell counts in most children, but the time to CD4(+) cell count of at least 500 cells was highly dependent upon baseline immunological status. Some children did not reach a CD4(+) T-cell count of 500 cells/μl despite 2 years of virologic suppression. AIDS-defining events occurred in 1% of the population, including children in whom virologic suppression and improved CD4(+) T-cell counts were achieved.

  17. Protection in Macaques Immunized with HIV-1 Candidate Vaccines Can Be Predicted Using the Kinetics of Their Neutralizing Antibodies

    PubMed Central

    Davis, David; Koornstra, Wim; Mortier, Daniella; Fagrouch, Zahra; Verschoor, Ernst J.; Heeney, Jonathan L.; Bogers, Willy M. J. M.

    2011-01-01

    Background A vaccine is needed to control the spread of human immunodeficiency virus type 1 (HIV-1). An in vitro assay that can predict the protection induced by a vaccine would facilitate the development of such a vaccine. A potential candidate would be an assay to quantify neutralization of HIV-1. Methods and Findings We have used sera from rhesus macaques that have been immunized with HIV candidate vaccines and subsequently challenged with simian human immunodeficiency virus (SHIV). We compared neutralization assays with different formats. In experiments with the standardized and validated TZMbl assay, neutralizing antibody titers against homologous SHIVSF162P4 pseudovirus gave a variable correlation with reductions in plasma viremia levels. The target cells used in the assays are not just passive indicators of virus infection but are actively involved in the neutralization process. When replicating virus was used with GHOST cell assays, events during the absorption phase, as well as the incubation phase, determine the level of neutralization. Sera that are associated with protection have properties that are closest to the traditional concept of neutralization: the concentration of antibody present during the absorption phase has no effect on the inactivation rate. In GHOST assays, events during the absorption phase may inactivate a fixed number, rather than a proportion, of virus so that while complete neutralization can be obtained, it can only be found at low doses particularly with isolates that are relatively resistant to neutralization. Conclusions Two scenarios have the potential to predict protection by neutralizing antibodies at concentrations that can be induced by vaccination: antibodies that have properties close to the traditional concept of neutralization may protect against a range of challenge doses of neutralization sensitive HIV isolates; a window of opportunity also exists for protection against isolates that are more resistant to

  18. Maternal LAMP/p55gagHIV-1 DNA Immunization Induces In Utero Priming and a Long-Lasting Immune Response in Vaccinated Neonates

    PubMed Central

    Rigato, Paula Ordonhez; Maciel, Milton; Goldoni, Adriana Letícia; Piubelli, Orlando Guerra; Orii, Noemia Mie; Marques, Ernesto Torres; August, Joseph Thomas; Duarte, Alberto José da Silva; Sato, Maria Notomi

    2012-01-01

    Infants born to HIV-infected mothers are at high risk of becoming infected during gestation or the breastfeeding period. A search is thus warranted for vaccine formulations that will prevent mother-to-child HIV transmission. The LAMP/gag DNA chimeric vaccine encodes the HIV-1 p55gag fused to the lysosome-associated membrane protein-1 (LAMP-1) and has been shown to enhance anti-Gag antibody (Ab) and cellular immune responses in adult and neonatal mice; such a vaccine represents a new concept in antigen presentation. In this study, we evaluated the effect of LAMP/gag DNA immunization on neonates either before conception or during pregnancy. LAMP/gag immunization of BALB/c mice before conception by the intradermal route led to the transfer of anti-Gag IgG1 Ab through the placenta and via breastfeeding. Furthermore, there were an increased percentage of CD4+CD25+Foxp3+T cells in the spleens of neonates. When offspring were immunized with LAMP/gag DNA, the anti-Gag Ab response and the Gag-specific IFN-γ-secreting cells were decreased. Inhibition of anti-Gag Ab production and cellular responses were not observed six months after immunization, indicating that maternal immunization did not interfere with the long-lasting memory response in offspring. Injection of purified IgG in conjunction with LAMP/gag DNA immunization decreased humoral and cytotoxic T-cell responses. LAMP/gag DNA immunization by intradermal injection prior to conception promoted the transfer of Ab, leading to a diminished response to Gag without interfering with the development of anti-Gag T- and B-cell memory. Finally, we assessed responses after one intravenous injection of LAMP/gag DNA during the last five days of pregnancy. The intravenous injection led to in utero immunization. In conclusion, DNA vaccine enconding LAMP-1 with Gag and other HIV-1 antigens should be considered in the development of a protective vaccine for the maternal/fetal and newborn periods. PMID:22355381

  19. Enzymatic removal of mannose moieties can increase the immune response to HIV-1 gp120 in vivo

    PubMed Central

    Banerjee, Kaustuv; Andjelic, Sofija; Klasse, Per Johan; Kang, Yun; Sanders, Rogier W.; Michael, Elizabeth; Durso, Robert J.; Ketas, Thomas J.; Olson, William C.; Moore, John P.

    2009-01-01

    The Env glycoproteins gp120 and gp41 are used in humoral immunity-based vaccines against human immunodeficiency virus (HIV-1) infection. One among many obstacles to such a vaccine is the structural defenses of Env glycoproteins that limit their immunogenicity. For example, gp120 mannose residues can induce immunosuppressive responses in vitro, including IL-10 expression, via mannose C-type lectin receptors on antigen-presenting cells. Here, we have investigated whether mannose removal alters gp120 immunogenicity in mice. Administering demannosylated gp120 (D-gp120) in the TH2-skewing adjuvant Alum induced ~50-fold higher titers of anti-gp120 IgG, compared to unmodified gp120. While the IgG subclass profile was predominantly TH2-associated IgG1, Abs of the TH1-associated IgG2a and IgG3 subclasses were also detectable in D-gp120 recipients. Immunizing with D-gp120 also improved T-cell responses. Giving an IL-10 receptor blocking MAb together with unmodified gp120 in Alum increased the anti-gp120 IgG titer, implicating IL-10 as a possible mediator of auto-suppressive responses to gp120. PMID:19410272

  20. Enzymatic removal of mannose moieties can increase the immune response to HIV-1 gp120 in vivo.

    PubMed

    Banerjee, Kaustuv; Andjelic, Sofija; Klasse, Per Johan; Kang, Yun; Sanders, Rogier W; Michael, Elizabeth; Durso, Robert J; Ketas, Thomas J; Olson, William C; Moore, John P

    2009-06-20

    The Env glycoproteins gp120 and gp41 are used in humoral immunity-based vaccines against human immunodeficiency virus (HIV-1) infection. One among many obstacles to such a vaccine is the structural defenses of Env glycoproteins that limit their immunogenicity. For example, gp120 mannose residues can induce immunosuppressive responses in vitro, including IL-10 expression, via mannose C-type lectin receptors on antigen-presenting cells. Here, we have investigated whether mannose removal alters gp120 immunogenicity in mice. Administering demannosylated gp120 (D-gp120) in the T(H)2-skewing adjuvant Alum induced approximately 50-fold higher titers of anti-gp120 IgG, compared to unmodified gp120. While the IgG subclass profile was predominantly T(H)2-associated IgG1, Abs of the T(H)1-associated IgG2a and IgG3 subclasses were also detectable in D-gp120 recipients. Immunizing with D-gp120 also improved T-cell responses. Giving an IL-10 receptor blocking MAb together with unmodified gp120 in Alum increased the anti-gp120 IgG titer, implicating IL-10 as a possible mediator of auto-suppressive responses to gp120.

  1. Induction of HIV-1 gag specific immune responses by cationic micelles mediated delivery of gag mRNA.

    PubMed

    Zhao, Mengnan; Li, Man; Zhang, Zhirong; Gong, Tao; Sun, Xun

    2016-09-01

    In recent years, mRNA-based vaccines have emerged to be a great alternative to DNA-based vaccines due to the safety of not inserting into host genome. However, mRNA molecules are single-stranded nucleic acids that are vulnerable under RNase existing in human skin and tissues. In this study, a self-assembled cationic nanomicelles based on polyethyleneimine-stearic acid (PSA) copolymer were developed to delivery HIV-1 gag encoding mRNA to dendritic cells and BALB/c mice. We evaluated the transfection efficiency and cell uptake efficiency of naked EGFP mRNA, PSA, PEI-2k and PEI-25k nanoparticles format on DC2.4 cell lines. Immune responses after sub-cutaneous administration of gag mRNA to BALB/c mice were notably induced by PSA as compared with naked gag mRNA. We found the PSA/mRNA nanomicelles were potent systems that can effectively deliver mRNA and induce antigen-specific immune response, stimulating various new vaccine strategies using mRNA.

  2. Successful vaccination of immune suppressed recipients using Listeria vector HIV-1 vaccines in helminth infected mice.

    PubMed

    Shollenberger, Lisa M; Bui, Cac; Paterson, Yvonne; Allen, Kelsey; Harn, Donald

    2013-04-12

    Vaccines for HIV, malaria and TB remain high priorities, especially for sub-Saharan populations. The question is: will vaccines currently in development for these diseases function in populations that have a high prevalence of helminth infection? Infection with helminth parasites causes immune suppression and a CD4+ Th2 skewing of the immune system, thereby impairing Th1-type vaccine efficacy. In this study, we conduct HIV vaccine trials in mice with and without chronic helminth infection to mimic the human vaccine recipient populations in Sub-Saharan Africa and other helminth parasite endemic regions of the world, as there is large overlap in global prevalence for HIV and helminth infection. Here, we demonstrate that Listeria monocytogenes functions as a vaccine vector to drive robust and functional HIV-specific cellular immune responses, irrespective of chronic helminth infection. This observation represents a significant advance in the field of vaccine research and underscores the concept that vaccines in the developmental pipeline should be effective in the target populations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Oral Immunization with a Recombinant Lactococcus lactis-Expressing HIV-1 Antigen on Group A Streptococcus Pilus Induces Strong Mucosal Immunity in the Gut.

    PubMed

    Chamcha, Venkateswarlu; Jones, Andrew; Quigley, Bernard R; Scott, June R; Amara, Rama Rao

    2015-11-15

    The induction of a potent humoral and cellular immune response in mucosal tissue is important for the development of an effective HIV vaccine. Most of the current HIV vaccines under development use the i.m. route for immunization, which is relatively poor in generating potent and long-lived mucosal immune responses. In this article, we explore the ability of an oral vaccination with a probiotic organism, Lactococcus lactis, to elicit HIV-specific immune responses in the mucosal and systemic compartments of BALB/c mice. We expressed the HIV-1 Gag-p24 on the tip of the T3 pilus of Streptococcus pyogenes as a fusion to the Cpa protein (LL-Gag). After four monthly LL-Gag oral immunizations, we observed strong Gag-specific IgG and IgA responses in serum, feces, and vaginal secretions. However, the Gag-specific CD8 T cell responses in the blood were at or below our detection limit. After an i.m. modified vaccinia Ankara/Gag boost, we observed robust Gag-specific CD8 T cell responses both in systemic and in mucosal tissues, including intraepithelial and lamina propria lymphocytes of the small intestine, Peyer's patches, and mesenteric lymph nodes. Consistent with strong immunogenicity, the LL-Gag induced activation of CD11c(+) CD11b(+) dendritic cells in the Peyer's patches after oral immunization. Our results demonstrate that oral immunization with L. lactis expressing an Ag on the tip of the group A Streptococcus pilus serves as an excellent vaccine platform to induce strong mucosal humoral and cellular immunity against HIV. Copyright © 2015 by The American Association of Immunologists, Inc.

  4. VS411 reduced immune activation and HIV-1 RNA levels in 28 days: randomized proof-of-concept study for antiviral-hyperactivation limiting therapeutics.

    PubMed

    Lori, Franco; De Forni, Davide; Katabira, Elly; Baev, Denis; Maserati, Renato; Calarota, Sandra A; Cahn, Pedro; Testori, Marco; Rakhmanova, Aza; Stevens, Michael R

    2012-01-01

    A new class of antiretrovirals, AntiViral-HyperActivation Limiting Therapeutics (AV-HALTs), has been proposed as a disease-modifying therapy to both reduce Human Immunodeficiency Virus Type 1 (HIV-1) RNA levels and the excessive immune activation now recognized as the major driver of not only the continual loss of CD4(+) T cells and progression to Acquired Immunodeficiency Syndrome (AIDS), but also of the emergence of both AIDS-defining and non-AIDS events that negatively impact upon morbidity and mortality despite successful (ie, fully suppressive) therapy. VS411, the first-in-class AV-HALT, combined low-dose, slow-release didanosine with low-dose hydroxycarbamide to accomplish both objectives with a favorable toxicity profile during short-term administration. Five dose combinations were administered as VS411 to test the AV-HALT Proof-of-Concept in HIV-1-infected subjects. Multinational, double-blind, 28-day Phase 2a dose-ranging Proof-of-Concept study of antiviral activity, immunological parameters, safety, and genotypic resistance in 58 evaluable antiretroviral-naïve HIV-1-infected adults. Randomization and allocation to study arms were carried out by a central computer system. Results were analyzed by ANOVA, Kruskal-Wallis, ANCOVA, and two-tailed paired t tests. VS411 was well-tolerated, produced significant reductions of HIV-1 RNA levels, increased CD4(+) T cell counts, and led to significant, rapid, unprecedented reductions of immune activation markers after 28 days despite incomplete viral suppression and without inhibiting HIV-1-specific immune responses. The didanosine 200 mg/HC 900 mg once-daily formulation demonstrated the greatest antiviral efficacy (HIV-1 RNA: -1.47 log(10) copies/mL; CD4(+) T cell count: +135 cells/mm(3)) and fewest adverse events. VS411 successfully established the Proof-of-Concept that AV-HALTs can combine antiviral efficacy with rapid, potentially beneficial reductions in the excessive immune system activation associated with HIV

  5. VS411 Reduced Immune Activation and HIV-1 RNA Levels in 28 Days: Randomized Proof-of-Concept Study for AntiViral-HyperActivation Limiting Therapeutics

    PubMed Central

    Lori, Franco; De Forni, Davide; Katabira, Elly; Baev, Denis; Maserati, Renato; Calarota, Sandra A.; Cahn, Pedro; Testori, Marco; Rakhmanova, Aza; Stevens, Michael R.

    2012-01-01

    Background A new class of antiretrovirals, AntiViral-HyperActivation Limiting Therapeutics (AV-HALTs), has been proposed as a disease-modifying therapy to both reduce Human Immunodeficiency Virus Type 1 (HIV-1) RNA levels and the excessive immune activation now recognized as the major driver of not only the continual loss of CD4+ T cells and progression to Acquired Immunodeficiency Syndrome (AIDS), but also of the emergence of both AIDS-defining and non-AIDS events that negatively impact upon morbidity and mortality despite successful (ie, fully suppressive) therapy. VS411, the first-in-class AV-HALT, combined low-dose, slow-release didanosine with low-dose hydroxycarbamide to accomplish both objectives with a favorable toxicity profile during short-term administration. Five dose combinations were administered as VS411 to test the AV-HALT Proof-of-Concept in HIV-1-infected subjects. Methods Multinational, double-blind, 28-day Phase 2a dose-ranging Proof-of-Concept study of antiviral activity, immunological parameters, safety, and genotypic resistance in 58 evaluable antiretroviral-naïve HIV-1-infected adults. Randomization and allocation to study arms were carried out by a central computer system. Results were analyzed by ANOVA, Kruskal-Wallis, ANCOVA, and two-tailed paired t tests. Results VS411 was well-tolerated, produced significant reductions of HIV-1 RNA levels, increased CD4+ T cell counts, and led to significant, rapid, unprecedented reductions of immune activation markers after 28 days despite incomplete viral suppression and without inhibiting HIV-1-specific immune responses. The didanosine 200 mg/HC 900 mg once-daily formulation demonstrated the greatest antiviral efficacy (HIV-1 RNA: −1.47 log10 copies/mL; CD4+ T cell count: +135 cells/mm3) and fewest adverse events. Conclusions VS411 successfully established the Proof-of-Concept that AV-HALTs can combine antiviral efficacy with rapid, potentially beneficial reductions in the excessive immune system

  6. Naloxone/alum mixture a potent adjuvant for HIV-1 vaccine: induction of cellular and poly-isotypic humoral immune responses.

    PubMed

    Velashjerdi Farahani, Sima; Reza Aghasadeghi, Mohammad; Memarnejadian, Arash; Faezi, Sobhan; Shahosseini, Zahra; Mahdavi, Mehdi

    2016-03-01

    In the present study we used a fusion peptide from HIV-1 p24 and Nef as vaccine model and adjuvant activity of Naloxone/alum mixture was evaluated in a peptide vaccine model. HIV-1 p24-Nef fusion peptide was synthesized. Female BALB/c mice were divided into five groups. The first group immunized subcutaneously with the p24-Nef fusion peptide adjuvanted with Naloxone/alum mixture and boosted with same protocol. The second was immunized with fusion peptide adjuvanted in alum. The control groups were injected with NLX (Group 3), Alum (Group 4), or PBS (Groups 5) under the same conditions. To determine the type of induced immune response, sera and splenocytes were analyzed by commercial ELISA method for total IgG and isotypes and cytokine secretion (IL-4 & IFN-γ), respectively. We have also used the ELISPOT assay to monitor changes in the frequency of IFN-γ-producing T cells. The proliferation of T cells was assessed using Brdu method and T-cell cytotoxicity was assessed with CFSE method. Immunization of mice with HIV-1 p24-Nef fusion peptide formulated in Naloxone/alum mixture significantly increased lymphocyte proliferation and shifted cytokine responses toward Th1 profile compared to all other groups. Analysis of humoral immune responses revealed that administration of HIV-1 p24-Nef fusion peptide with Naloxone/alum mixture significantly increased specific IgG responses and also increased IgG1,IgG2a, IgG2b, IgG3, and IgM vs. alum-adjuvanted vaccine groups. Naloxone/alum mixture as an adjuvant could improve cellular and humoral immune response for HIV vaccine model and this adjuvant maybe useful for HIV vaccine model in human clinical trial.

  7. Increased Intrathecal Immune Activation in Virally Suppressed HIV-1 Infected Patients with Neurocognitive Impairment

    PubMed Central

    Edén, Arvid; Marcotte, Thomas D.; Heaton, Robert K.; Nilsson, Staffan; Zetterberg, Henrik; Fuchs, Dietmar; Franklin, Donald; Price, Richard W.; Grant, Igor; Letendre, Scott L.; Gisslén, Magnus

    2016-01-01

    Objective Although milder forms of HIV-associated neurocognitive disorder (HAND) remain prevalent, a correlation to neuronal injury has not been established in patients on antiretroviral therapy (ART). We examined the relationship between mild HAND and CSF neurofilament light protein (NFL), a biomarker of neuronal injury; and CSF neopterin, a biomarker of CNS immunoactivation, in virally suppressed patients on antiretroviral therapy (ART). Design and Methods We selected 99 subjects on suppressive ART followed longitudinally from the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) study. Based on standardized comprehensive neurocognitive performance (NP) testing, subjects were classified as neurocognitively normal (NCN; n = 29) or impaired (NCI; n = 70). The NCI group included subjects with asymptomatic (ANI; n = 37) or mild (MND; n = 33) HAND. CSF biomarkers were analyzed on two occasions. Results Geometric mean CSF neopterin was 25% higher in the NCI group (p = 0.04) and NFL and neopterin were significantly correlated within the NCI group (r = 0.30; p<0.001) but not in the NCN group (r = -0.13; p = 0.3). Additionally, a trend towards higher NFL was seen in the NCI group (p = 0.06). Conclusions Mild HAND was associated with increased intrathecal immune activation, and the correlation between neopterin and NFL found in NCI subjects indicates an association between neurocognitive impairment, CNS inflammation and neuronal damage. Together these findings suggest that NCI despite ART may represent an active pathological process within the CNS that needs further characterization in prospective studies. PMID:27295036

  8. Live attenuated Salmonella displaying HIV-1 10E8 epitope on fimbriae: systemic and mucosal immune responses in BALB/c mice by mucosal administration

    PubMed Central

    Li, Qing-Hai; Jin, Gang; Wang, Jia-Ye; Li, Hai-Ning; Liu, Huidi; Chang, Xiao-Yun; Wang, Fu-Xiang; Liu, Shu-Lin

    2016-01-01

    The HIV-1 membrane proximal external region (MPER) that is targeted by several broadly neutralizing antibodies (BNAbs) has been considered a potential immunogen for vaccine development. However, to date the immunogenicity of these BNAb epitopes has not been made sufficiently adequate. In the present work, we used live attenuated Salmonella as a platform to present the HIV-1 MPER 10E8 epitope in the fimbriae. The insertion of the 10E8 epitope into the fimbriae had no significant influence on the expression and the absorption capacity of bacterial fimbriae, nor on the virulence and invasiveness of the attenuated Salmonella. After oral administration of the vaccine construct to mice followed by 10E8 epitope peptide boost, specific antibody responses in serum and mucosa as well as memory lymphocytes in spleen and plasma cells in bone marrow were induced. We also found that the live attenuated Salmonella vector directed the immunity toward Th1 bias, induced Th1 and Th2 cytokine responses and stimulated significant B cell differentiation into GC B, memory B and plasma cells. Therefore, we propose that the live attenuated Salmonella constitutively expressing HIV-1 BNAb epitopes on the fimbriae will be an effective approach to improving immune microenvironment and enhancing the immunogenicity of HIV-1 epitope vaccines. PMID:27411313

  9. HIV-1 vaccines

    PubMed Central

    Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

    2014-01-01

    The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure. PMID:24637946

  10. Developing strategies for HIV-1 eradication

    PubMed Central

    Durand, Christine M.; Blankson, Joel N.; Siliciano, Robert F.

    2014-01-01

    Highly active antiretroviral therapy (HAART) suppresses HIV-1 replication, transforming the outlook for infected patients. However, reservoirs of replication-competent forms of the virus persist during HAART, and when treatment is stopped, high rates of HIV-1 replication return. Recent insights into HIV-1 latency, as well as a report that HIV-1 infection was eradicated in one individual, have renewed interest in finding a cure for HIV-1 infection. Strategies for HIV-1 eradication include gene therapy and hematopoietic stem cell transplantation, stimulating host immunity to control HIV-1 replication, and targeting latent HIV-1 in resting memory CD4+ T cells. Future efforts should aim to provide better understanding of how to reconstitute the CD4+ T cell compartment with genetically engineered cells, exert immune control over HIV-1 replication, and identify and eliminate all viral reservoirs. PMID:22867874

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

    PubMed Central

    García-Arriaza, Juan; Nájera, José Luis; Gómez, Carmen E.; Sorzano, Carlos Oscar S.; Esteban, Mariano

    2010-01-01

    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 1β, respectively (referred as MVA-B ΔA41L/ΔB16R). 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 ΔA41L/ΔB16R. 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 ΔA41L/ΔB16R 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 ΔA41L/ΔB16R 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 ΔA41L/ΔB16R induced in mice robust, polyfunctional and durable T

  12. Animal poxvirus vaccines: a comprehensive review.

    PubMed

    Bhanuprakash, Veerakyathappa; Hosamani, Madhusudan; Venkatesan, Gnanavel; Balamurugan, Vinayagamurthy; Yogisharadhya, Revanaiah; Singh, Raj Kumar

    2012-11-01

    The family Poxviridae includes several viruses of medical and veterinary importance. Global concerted efforts combined with an intensive mass-vaccination campaign with highly efficaceious live vaccine of vaccinia virus have led to eradication of smallpox. However, orthopoxviruses affecting domestic animals continue to cause outbreaks in several endemic countries. Different kinds of vaccines starting from conventional inactivated/attenuated to recombinant protein-based vaccines have been used for control of poxvirus infections. Live virus homologous vaccines are currently in use for diseases including capripox, parapox, camelpox and fowlpox, and these vaccines are highly effective in eliciting (with the exception of parapoxviruses) long-lasting immunity. Attenuated strains of poxviruses have been exploited as vectored vaccines to deliver heterologous immunogens, many of them being licensed for use in animals. Worthy of note are vaccinia virus, fowlpox virus, capripoxvirus, parapoxvirus and canary pox, which have been successfully used for developing new-generation vaccines targeting many important pathogens. Remarkable features of these vaccines are thermostability and their ability to engender both cellular and humoral immune responses to the target pathogens. This article updates the important vaccines available for poxviruses of livestock and identifies some of the research gaps in the present context of poxvirus research.

  13. DNA vaccine molecular adjuvants SP-D-BAFF and SP-D-APRIL enhance anti-gp120 immune response and increase HIV-1 neutralizing antibody titers.

    PubMed

    Gupta, Sachin; Clark, Emily S; Termini, James M; Boucher, Justin; Kanagavelu, Saravana; LeBranche, Celia C; Abraham, Sakhi; Montefiori, David C; Khan, Wasif N; Stone, Geoffrey W

    2015-04-01

    Broadly neutralizing antibodies (bNAbs) specific for conserved epitopes on the HIV-1 envelope (Env) are believed to be essential for protection against multiple HIV-1 clades. However, vaccines capable of stimulating the production of bNAbs remain a major challenge. Given that polyreactivity and autoreactivity are considered important characteristics of anti-HIV bNAbs, we designed an HIV vaccine incorporating the molecular adjuvants BAFF (B cell activating factor) and APRIL (a proliferation-inducing ligand) with the potential to facilitate the maturation of polyreactive and autoreactive B cells as well as to enhance the affinity and/or avidity of Env-specific antibodies. We designed recombinant DNA plasmids encoding soluble multitrimers of BAFF and APRIL using surfactant protein D as a scaffold, and we vaccinated mice with these molecular adjuvants using DNA and DNA-protein vaccination strategies. We found that immunization of mice with a DNA vaccine encoding BAFF or APRIL multitrimers, together with interleukin 12 (IL-12) and membrane-bound HIV-1 Env gp140, induced neutralizing antibodies against tier 1 and tier 2 (vaccine strain) viruses. The APRIL-containing vaccine was particularly effective at generating tier 2 neutralizing antibodies following a protein boost. These BAFF and APRIL effects coincided with an enhanced germinal center (GC) reaction, increased anti-gp120 antibody-secreting cells, and increased anti-gp120 functional avidity. Notably, BAFF and APRIL did not cause indiscriminate B cell expansion or an increase in total IgG. We propose that BAFF and APRIL multitrimers are promising molecular adjuvants for vaccines designed to induce bNAbs against HIV-1. Recent identification of antibodies that neutralize most HIV-1 strains has revived hopes and efforts to create novel vaccines that can effectively stimulate HIV-1 neutralizing antibodies. However, the multiple immune evasion properties of HIV have hampered these efforts. These include the instability of

  14. Increased immunogenicity of HIV-1 p24 and gp120 following immunization with gp120/p24 fusion protein vaccine expressing alpha-gal epitopes.

    PubMed

    Abdel-Motal, Ussama M; Wang, Shixia; Awad, Amany; Lu, Shan; Wigglesworth, Kim; Galili, Uri

    2010-02-17

    Developing an effective HIV-1 vaccine will require strategies to enhance antigen presentation to the immune system. In a previous study we demonstrated a marked increase in immunogenicity of the highly glycosylated HIV-1 gp120 protein following enzymatic addition of alpha-gal epitopes to the carbohydrate chains. In the present study we determined whether gp120(alphagal) can also serve as an effective platform for targeting other HIV-1 proteins to APC and thus increase immunogenicity of both proteins. For this purpose we produced a recombinant fusion protein between gp120 and the HIV-1 matrix p24 protein (gp120/p24). Multiple alpha-gal epitopes were synthesized enzymatically on the gp120 portion of the fusion protein to generate a gp120(alphagal)/p24 vaccine. Immune responses to gp120(alphagal)/p24 compared to gp120/p24 vaccine lacking alpha-gal epitopes were evaluated in alpha1,3galactosyltransferase knockout (KO) mice. These mice lack alpha-gal epitopes and, therefore, are capable of producing the anti-Gal antibody. T cell responses to p24, as assessed by ELISPOT and by CD8+ T cells intracellular staining assays for IFNgamma, was on average 12- and 10-fold higher, respectively, in gp120(alphagal)/p24 immunized mice than in mice immunized with gp120/p24. In addition, cellular and humoral immune responses against gp120 were higher by 10-30-fold in mice immunized with gp120(alphagal)/p24 than in gp120/p24 immunized mice. Our data suggest that the alpha-gal epitopes on the gp120 portion of the fusion protein can significantly augment the immunogenicity of gp120, as well as that of the fused viral protein which lacks alpha-gal epitopes. This strategy of anti-Gal mediated targeting to APC may be used for production of effective HIV-1 vaccines comprised of various viral proteins fused to gp120.

  15. Deletion of the Vaccinia Virus N2L Gene Encoding an Inhibitor of IRF3 Improves the Immunogenicity of Modified Vaccinia Virus Ankara Expressing HIV-1 Antigens

    PubMed Central

    García-Arriaza, Juan; Gómez, Carmen E.; Sorzano, Carlos Óscar S.

    2014-01-01

    ABSTRACT A modified vaccinia virus Ankara poxvirus vector expressing the HIV-1 Env, Gag, Pol, and Nef antigens from clade B (MVA-B) is currently being tested in clinical trials. To improve its immunogenicity, we have generated and characterized the immune profile of MVA-B containing a deletion of the vaccinia viral gene N2L, which codes for an inhibitor of IRF3 (MVA-B ΔN2L). Deletion of N2L had no effect on virus growth kinetics or on the expression of HIV-1 antigens; hence, the N2 protein is not essential for MVA replication. The innate immune responses triggered by MVA-B ΔN2L revealed an increase in beta interferon, proinflammatory cytokines, and chemokines. Mouse prime-boost protocols showed that MVA-B ΔN2L improves the magnitude and polyfunctionality of HIV-1-specific CD4+ and CD8+ T cell adaptive and memory immune responses, with most of the HIV-1 responses mediated by CD8+ T cells. In the memory phase, HIV-1-specific CD8+ T cells with an effector phenotype were predominant and in a higher percentage with MVA-B ΔN2L than with MVA-B. In both immunization groups, CD4+ and CD8+ T cell responses were directed mainly against Env. Furthermore, MVA-B ΔN2L in the memory phase enhanced levels of antibody against Env. For the vector immune responses, MVA-B ΔN2L induced a greater magnitude and polyfunctionality of VACV-specific CD8+ T memory cells than MVA-B, with an effector phenotype. These results revealed the immunomodulatory role of N2L, whose deletion enhanced the innate immunity and improved the magnitude and quality of HIV-1-specific T cell adaptive and memory immune responses. These findings are relevant for the optimization of poxvirus vectors as vaccines. IMPORTANCE On the basis of the limited efficacy of the RV144 phase III clinical trial, new optimized poxvirus vectors as vaccines against HIV/AIDS are needed. Here we have generated and characterized a new HIV/AIDS vaccine candidate on the basis of the poxvirus MVA vector expressing HIV-1 Env, Gag, Pol

  16. The Efficacy of T Cell-Mediated Immune Responses Is Reduced by the Envelope Protein of the Chimeric HIV-1/SIV-KB9 Virus In Vivo1

    PubMed Central

    Stevceva, Liljana; Yoon, Victor; Carville, Angela; Pacheco, Beatriz; Santosuosso, Michael; Korioth-Schmitz, Birgit; Mansfield, Keith; Poznansky, Mark C.

    2014-01-01

    Gp120 is a critical component of the envelope of HIV-1. Its role in viral entry is well described. In view of its position on the viral envelope, gp120 is a part of the retrovirus that immune cells encounter first and has the potential to influence antiretroviral immune responses. We propose that high levels of gp120 are present in tissues and may contribute to the failure of the immune system to fully control and ultimately clear the virus. Herein, we show for the first time that lymphoid tissues from acutely HIV-1/SIV (SHIV)-KB9-infected macaques contain deposits of gp120 at concentrations that are high enough to induce suppressive effects on T cells, thus negatively regulating the antiviral CTL response and contributing to virus survival and persistence. We also demonstrate that SHIV-KB9 gp120 influences functional T cell responses during SHIV infection in a manner that suppresses degranulation and cytokine secretion by CTLs. Finally, we show that regulatory T cells accumulate in lymphoid tissues during acute infection and that they respond to gp120 by producing TGFβ, a known suppressant of cytotoxic T cell activity. These findings have significant implications for our understanding of the contribution of non-entry-related functions of HIV-1 gp120 to the pathogenesis of HIV/AIDS. PMID:18832708

  17. Poxvirus membrane biogenesis.

    PubMed

    Moss, Bernard

    2015-05-01

    Poxviruses differ from most DNA viruses by replicating entirely within the cytoplasm. The first discernible viral structures are crescents and spherical immature virions containing a single lipoprotein membrane bilayer with an external honeycomb lattice. Because this viral membrane displays no obvious continuity with a cellular organelle, a de novo origin was suggested. Nevertheless, transient connections between viral and cellular membranes could be difficult to resolve. Despite the absence of direct evidence, the intermediate compartment (ERGIC) between the endoplasmic reticulum (ER) and Golgi apparatus and the ER itself were considered possible sources of crescent membranes. A break-through in understanding poxvirus membrane biogenesis has come from recent studies of the abortive replication of several vaccinia virus null mutants. Novel images showing continuity between viral crescents and the ER and the accumulation of immature virions in the expanded ER lumen provide the first direct evidence for a cellular origin of this poxvirus membrane.

  18. Effect of Schistosoma mansoni Infection on Innate and HIV-1-Specific T-Cell Immune Responses in HIV-1-Infected Ugandan Fisher Folk.

    PubMed

    Obuku, Andrew Ekii; Asiki, Gershim; Abaasa, Andrew; Ssonko, Isaac; Harari, Alexandre; van Dam, Govert J; Corstjens, Paul L; Joloba, Moses; Ding, Song; Mpendo, Juliet; Nielsen, Leslie; Kamali, Anatoli; Elliott, Alison M; Pantaleo, Giuseppe; Kaleebu, Pontiano; Pala, Pietro

    2016-07-01

    In Uganda, fisher folk have HIV prevalence rates, about four times higher than the national average, and are often coinfected with Schistosoma mansoni. We hypothesized that innate immune responses and HIV-specific Th1 immune responses might be downmodulated in HIV/S. mansoni-coinfected individuals compared with HIV+/S. mansoni-negative individuals. We stimulated whole blood with innate receptor agonists and analyzed supernatant cytokines by Luminex. We evaluated HIV-specific responses by intracellular cytokine staining for IFN-γ, IL-2, and TNF-α. We found that the plasma viral load and CD4 count were similar between the HIV+SM+ and HIV+SM- individuals. In addition, the TNF-α response to the imidazoquinoline compound CL097 and β-1, 3-glucan (curdlan), was significantly higher in HIV/S. mansoni-coinfected individuals compared with HIV only-infected individuals. The frequency of HIV-specific IFN-γ+IL-2-TNF-α- CD8 T cells and IFN-γ+IL-2-TNF-α+ CD4 T cells was significantly higher in HIV/S. mansoni-coinfected individuals compared with HIV only-infected individuals. These findings do not support the hypothesis that S. mansoni downmodulates innate or HIV-specific Th1 responses in HIV/S. mansoni-coinfected individuals.

  19. A correlate of HIV-1 control consisting of both innate and adaptive immune parameters best predicts viral load by multivariable analysis in HIV-1 infected viremic controllers and chronically-infected non-controllers.

    PubMed

    Tomescu, Costin; Liu, Qin; Ross, Brian N; Yin, Xiangfan; Lynn, Kenneth; Mounzer, Karam C; Kostman, Jay R; Montaner, Luis J

    2014-01-01

    HIV-1 infected viremic controllers maintain durable viral suppression below 2000 copies viral RNA/ml without anti-retroviral therapy (ART), and the immunological factor(s) associated with host control in presence of low but detectable viral replication are of considerable interest. Here, we utilized a multivariable analysis to identify which innate and adaptive immune parameters best correlated with viral control utilizing a cohort of viremic controllers (median 704 viral RNA/ml) and non-controllers (median 21,932 viral RNA/ml) that were matched for similar CD4+ T cell counts in the absence of ART. We observed that HIV-1 Gag-specific CD8+ T cell responses were preferentially targeted over Pol-specific responses in viremic controllers (p = 0.0137), while Pol-specific responses were positively associated with viral load (rho = 0.7753, p = 0.0001, n = 23). Viremic controllers exhibited significantly higher NK and plasmacytoid dendritic cells (pDC) frequency as well as retained expression of the NK CD16 receptor and strong target cell-induced NK cell IFN-gamma production compared to non-controllers (p<0.05). Despite differences in innate and adaptive immune function however, both viremic controllers (p<0.05) and non-controller subjects (p<0.001) exhibited significantly increased CD8+ T cell activation and spontaneous NK cell degranulation compared to uninfected donors. Overall, we identified that a combination of innate (pDC frequency) and adaptive (Pol-specific CD8+ T cell responses) immune parameters best predicted viral load (R2 = 0.5864, p = 0.0021, n = 17) by a multivariable analysis. Together, this data indicates that preferential Gag-specific over Pol-specific CD8+ T cell responses along with a retention of functional innate subsets best predict host control over viral replication in HIV-1 infected viremic controllers compared to chronically-infected non-controllers.

  20. Replicative fitness of transmitted HIV-1 drives acute immune activation, proviral load in memory CD4+ T cells, and disease progression.

    PubMed

    Claiborne, Daniel T; Prince, Jessica L; Scully, Eileen; Macharia, Gladys; Micci, Luca; Lawson, Benton; Kopycinski, Jakub; Deymier, Martin J; Vanderford, Thomas H; Nganou-Makamdop, Krystelle; Ende, Zachary; Brooks, Kelsie; Tang, Jianming; Yu, Tianwei; Lakhi, Shabir; Kilembe, William; Silvestri, Guido; Douek, Daniel; Goepfert, Paul A; Price, Matthew A; Allen, Susan A; Paiardini, Mirko; Altfeld, Marcus; Gilmour, Jill; Hunter, Eric

    2015-03-24

    HIV-1 infection is characterized by varying degrees of chronic immune activation and disruption of T-cell homeostasis, which impact the rate of disease progression. A deeper understanding of the factors that influence HIV-1-induced immunopathology and subsequent CD4(+) T-cell decline is critical to strategies aimed at controlling or eliminating the virus. In an analysis of 127 acutely infected Zambians, we demonstrate a dramatic and early impact of viral replicative capacity (vRC) on HIV-1 immunopathogenesis that is independent of viral load (VL). Individuals infected with high-RC viruses exhibit a distinct inflammatory cytokine profile as well as significantly elevated T-cell activation, proliferation, and CD8(+) T-cell exhaustion, during the earliest months of infection. Moreover, the vRC of the transmitted virus is positively correlated with the magnitude of viral burden in naive and central memory CD4(+) T-cell populations, raising the possibility that transmitted viral phenotypes may influence the size of the initial latent viral reservoir. Taken together, these findings support an unprecedented role for the replicative fitness of the founder virus, independent of host protective genes and VL, in influencing multiple facets of HIV-1-related immunopathology, and that a greater focus on this parameter could provide novel approaches to clinical interventions.

  1. Conjugated anionic PEG-citrate G2 dendrimer with multi-epitopic HIV-1 vaccine candidate enhance the cellular immune responses in mice.

    PubMed

    Abdoli, Asghar; Radmehr, Nina; Bolhassani, Azam; Eidi, Akram; Mehrbod, Parvaneh; Motevalli, Fatemeh; Kianmehr, Zahra; Chiani, Mohsen; Mahdavi, Mehdi; Yazdani, Shaghayegh; Ardestani, Mehdi Shafiee; Kandi, Mohammad Reza; Aghasadeghi, Mohammad Reza

    2017-02-20

    Multi-epitope vaccines might cause immunity against multiple antigenic targets. Four immunodominant epitopes of HIV-1 genome were used to construct a polytope vaccine, formulated by dendrimer. Two regimens of polytopes mixture with dendrimer were utilized to immunize BALB/c mice. Adjuvants were also used to boost immune responses. The conjugated polytope could arouse significant cellular immune responses (P < 0.05) and Th1 response showed higher intensity compared to Th2 (P < 0.05). Our study depicted that conjugated dendrimer with multi-epitopic rHIVtop4 would efficiently induce cell-mediated immune responses and might be considered as promising delivery system for vaccines formulation.

  2. Metabolic and Immune Activation Effects of Treatment Interruption in Chronic HIV-1 Infection: Implications for Cardiovascular Risk

    PubMed Central

    Tebas, Pablo; Henry, William Keith; Matining, Roy; Weng-Cherng, Deborah; Schmitz, John; Valdez, Hernan; Jahed, Nasreen; Myers, Laurie; Powderly, William G.; Katzenstein, David

    2008-01-01

    Background Concern about costs and antiretroviral therapy (ART)-associated toxicities led to the consideration of CD4 driven strategies for the management of HIV. That approach was evaluated in the SMART trial that reported an unexpected increase of cardiovascular events after treatment interruption (TI). Our goal was to evaluate fasting metabolic changes associated with interruption of antiretroviral therapy and relate them to changes of immune activation markers and cardiovascular risk. Methodology ACTG 5102 enrolled 47 HIV-1-infected subjects on stable ART, with <200 HIV RNA copies/mL and CD4 cell count ≥500 cells/µL. Subjects were randomly assigned to continue ART for 18 weeks with or without 3 cycles of interleukin-2 (IL-2) (cycle = 4.5 million IU sc BID x 5 days every 8 weeks). After 18 weeks ART was discontinued in all subjects until the CD4 cell count dropped below 350 cells/µL. Glucose and lipid parameters were evaluated every 8 weeks initially and at weeks 2, 4, 8 and every 8 weeks after TI. Immune activation was evaluated by flow-cytometry and soluble TNFR2 levels. Principal Findings By week 8 of TI, levels of total cholesterol (TC) (median (Q1, Q3) (−0.73 (−1.19, −0.18) mmol/L, p<0.0001), LDL, HDL cholesterol (−0.36(−0.73,−0.03)mmol/L, p = 0.0007 and −0.05(−0.26,0.03), p = 0.0033, respectively) and triglycerides decreased (−0.40 (−0.84, 0.07) mmol/L, p = 0.005). However the TC/HDL ratio remained unchanged (−0.09 (−1.2, 0.5), p = 0.2). Glucose and insulin levels did not change (p = 0.6 and 0.8, respectively). After TI there was marked increase in immune activation (CD8+/HLA-DR+/CD38+ cells, 34% (13, 43), p<0.0001) and soluble TNFR2 (1089 ng/L (−189, 1655), p = 0.0008) coinciding with the rebound of HIV viremia. Conclusions Our data suggests that interrupting antiretroviral therapy does not reduce cardiovascular disease (CVD) risk, as the improvements in lipid parameters are modest and overshadowed

  3. HIV-1 Infection of Macrophages Dysregulates Innate Immune Responses to Mycobacterium tuberculosis by Inhibition of Interleukin-10

    PubMed Central

    Tomlinson, Gillian S.; Bell, Lucy C. K.; Walker, Naomi F.; Tsang, Jhen; Brown, Jeremy S.; Breen, Ronan; Lipman, Marc; Katz, David R.; Miller, Robert F.; Chain, Benjamin M.; Elkington, Paul T. G.; Noursadeghi, Mahdad

    2014-01-01

    Human immunodeficiency virus (HIV)–1 and Mycobacterium tuberculosis (M. tuberculosis) both target macrophages, which are key cells in inflammatory responses and their resolution. Therefore, we tested the hypothesis that HIV-1 may modulate macrophage responses to coinfection with M. tuberculosis. HIV-1 caused exaggerated proinflammatory responses to M. tuberculosis that supported enhanced virus replication, and were associated with deficient stimulus-specific induction of anti-inflammatory interleukin (IL)–10 and attenuation of mitogen-activated kinase signaling downstream of Toll-like receptor 2 and dectin-1 stimulation. Our in vitro data were mirrored by lower IL-10 and higher proinflammatory IL-1β in airway samples from HIV-1–infected patients with pulmonary tuberculosis compared with those with non-tuberculous respiratory tract infections. Single-round infection of macrophages with HIV-1 was sufficient to attenuate IL-10 responses, and antiretroviral treatment of replicative virus did not affect this phenotype. We propose that deficient homeostatic IL-10 responses may contribute to the immunopathogenesis of active tuberculosis and propagation of virus infection in HIV-1/M. tuberculosis coinfection. PMID:24265436

  4. Immunization with an SIV-based IDLV Expressing HIV-1 Env 1086 Clade C Elicits Durable Humoral and Cellular Responses in Rhesus Macaques

    PubMed Central

    Negri, Donatella; Blasi, Maria; LaBranche, Celia; Parks, Robert; Balachandran, Harikrishnan; Lifton, Michelle; Shen, Xiaoying; Denny, Thomas; Ferrari, Guido; Vescio, Maria Fenicia; Andersen, Hanne; Montefiori, David C; Tomaras, Georgia D; Liao, Hua-Xin; Santra, Sampa; Haynes, Barton F; Klotman, Mary E; Cara, Andrea

    2016-01-01

    The design of an effective HIV-1 vaccine remains a major challenge. Several vaccine strategies based on viral vectors have been evaluated in preclinical and clinical trials, with largely disappointing results. Integrase defective lentiviral vectors (IDLV) represent a promising vaccine candidate given their ability to induce durable and protective immune responses in mice after a single immunization. Here, we evaluated the immunogenicity of a SIV-based IDLV in nonhuman primates. Six rhesus monkeys were primed intramuscularly with IDLV-Env and boosted with the same vector after 1 year. A single immunization with IDLV-Env induced broad humoral and cellular immune responses that waned over time but were still detectable at 1 year postprime. The boost with IDLV-Env performed at 1 year from the prime induced a remarkable increase in both antibodies and T-cell responses. Antibody binding specificity showed a predominant cross-clade gp120-directed response. Monkeys' sera efficiently blocked anti-V2 and anti-CD4 binding site antibodies, neutralized the tier 1 MW965.26 pseudovirus and mediated antibody-dependent cellular cytotoxicity (ADCC). Durable polyfunctional Env-specific T-cell responses were also elicited. Our study demonstrates that an IDLV-Env-based vaccine induces functional, comprehensive, and durable immune responses in Rhesus macaques. These results support further evaluation of IDLV as a new HIV-1 vaccine delivery platform. PMID:27455880

  5. Antibody Light-Chain-Restricted Recognition of the Site of Immune Pressure in the RV144 HIV-1 Vaccine Trial Is Phylogenetically Conserved

    DOE PAGES

    Wiehe, Kevin; Easterhoff, David; Luo, Kan; ...

    2014-11-29

    In HIV-1, the ability to mount antibody responses to conserved, neutralizing epitopes is critical for protection. Here we have studied the light chain usage of human and rhesus macaque antibodies targeted to a dominant region of the HIV-1 envelope second variable (V2) region involving lysine (K) 169, the site of immune pressure in the RV144 vaccine efficacy trial. We found that humans and rhesus macaques used orthologous lambda variable gene segments encoding a glutamic acid-aspartic acid (ED) motif for K169 recognition. Structure determination of an unmutated ancestor antibody demonstrated that the V2 binding site was preconfigured for ED motif-mediated recognitionmore » prior to maturation. Thus, light chain usage for recognition of the site of immune pressure in the RV144 trial is highly conserved across species. In conclusion, these data indicate that the HIV-1 K169-recognizing ED motif has persisted over the diversification between rhesus macaques and humans, suggesting an evolutionary advantage of this antibody recognition mode.« less

  6. Antibody light chain-restricted recognition of the site of immune pressure in the RV144 HIV-1 vaccine trial is phylogenetically conserved

    PubMed Central

    Wiehe, Kevin; Easterhoff, David; Luo, Kan; Nicely, Nathan I.; Bradley, Todd; Jaeger, Frederick H.; Dennison, S. Moses; Zhang, Ruijun; Lloyd, Krissey E.; Stolarchuk, Christina; Parks, Robert; Sutherland, Laura L.; Scearce, Richard M.; Morris, Lynn; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Pitisuttithum, Punnee; Rerks-Ngarm, Supachai; Sinangil, Faruk; Phogat, Sanjay; Michael, Nelson L.; Kim, Jerome H.; Kelsoe, Garnett; Montefiori, David C.; Tomaras, Georgia D.; Bonsignori, Mattia; Santra, Sampa; Kepler, Thomas B.; Alam, S. Munir; Moody, M. Anthony; Liao, Hua-Xin; Haynes, Barton F.

    2015-01-01

    SUMMARY In HIV-1, the ability to mount antibody responses to conserved, neutralizing epitopes is critical for protection. Here we have studied the light chain usage of human and rhesus macaque antibodies targeted to a dominant region of the HIV-1 envelope second variable (V2) region involving lysine (K)169, the site of immune pressure in the RV144 vaccine efficacy trial. We found that humans and rhesus macaques used orthologous lambda variable gene segments encoding a glutamic acid-aspartic acid (ED) motif for K169 recognition. Structure determination of an unmutated ancestor antibody demonstrated that the V2 binding site was pre-configured for ED motif-mediated recognition prior to maturation. Thus, light chain usage for recognition of the site of immune pressure in the RV144 trial is highly conserved across species. These data indicate the HIV-1 K169-recognizing ED motif has persisted over the diversification between rhesus macaques and humans, suggesting an evolutionary advantage of this antibody recognition mode. PMID:25526306

  7. Intravaginal immunization using the recombinant HIV-1 clade-C trimeric envelope glycoprotein CN54gp140 formulated within lyophilized solid dosage forms

    PubMed Central

    Donnelly, Louise; Curran, Rhonda M.; Tregoning, John S.; McKay, Paul F.; Cole, Tom; Morrow, Ryan J.; Kett, Vicky L.; Andrews, Gavin P.; Woolfson, A. David; Malcolm, R. Karl; Shattock, Robin J.

    2011-01-01

    Vaccine-mediated prevention of primary HIV-1 infection at the heterosexual mucosal portal of entry may be facilitated by highly optimised formulations or drug delivery devices for intravaginal (i.vag) immunization. Previously we described hydroxyethylcellulose (HEC)-based rheologically structured gel vehicles (RSVs) for vaginal immunization of an HIV-1 vaccine candidate, a soluble recombinant trimeric HIV-1 clade-C envelope glycoprotein designated CN54gp140. Here we investigated the efficacy of lyophilized solid dosage formulations (LSDFs) for prolonging antigen stability and as i.vag delivery modalities. LSDFs were designed and developed that upon i.vag administration they would reconstitute with the imbibing of vaginal fluid to mucoadhesive, site-retentive semi-solids. Mice were immunized with lyophilized equivalents of (i) RSVs, (ii) modified versions of the RSVs more suited to lyophilization (sodium carboxymethyl cellulose (NaCMC)-based gels) and (iii) Carbopol® gel, all containing CN54gp140. NaCMC-based LSDFs provided significantly enhanced antigen stability compared to aqueous-based RSVs. Rheological analysis indicated the NaCMC-based LSDFs would offer enhanced vaginal retention in woman compared to more conventional vaginal gel formulations. All LSDFs were well tolerated in the mouse model. Following i.vag administration, all LSDFs boosted systemic CN54gp140-specific antibody responses in sub-cutaneously primed mice. Induction of CN54gp140-specific antibody responses in the female genital tract was evident. Of all the LSDFs the fastest releasing which was lyophilized Carbopol® gel elicited immune responses comparable to buffer instillation of antigen suggesting that rather than slower sustained release, initial high burst release from the LSDFs may suffice. The boosting of specific immune responses upon i.vag administration indicates that LSDFs are viable mucosal vaccine delivery modalities promoting antigen stability and facilitating intimate exposure of

  8. T-Cell Immune Responses Against Env from CRF12_BF and Subtype B HIV-1 Show High Clade-Specificity that Can Be Overridden by Multiclade Immunizations

    PubMed Central

    Mónaco, Daniela C.; Rodríguez, Ana M.; Pascutti, María F.; Carobene, Mauricio; Falivene, Juliana; Gómez, Alejandro; Maeto, Cynthia; Turk, Gabriela; Nájera, José L.; Esteban, Mariano; Gherardi, M. Magdalena

    2011-01-01

    Background The extreme genetic diversity of the human immunodeficiency virus type 1 (HIV-1) poses a daunting challenge to the generation of an effective AIDS vaccine. In Argentina, the epidemic is characterized by the high prevalence of infections caused by subtype B and BF variants. The aim of this study was to characterize in mice the immunogenic and antigenic properties of the Env protein from CRF12_BF in comparison with clade B, employing prime-boost schemes with the combination of recombinant DNA and vaccinia virus (VV) vectors. Methodology/Principal Findings As determined by ELISPOT from splenocytes of animals immunized with either EnvBF or EnvB antigens, the majority of the cellular responses to Env were found to be clade-specific. A detailed peptide mapping of the responses reveal that when there is cross-reactivity, there are no amino acid changes in the peptide sequence or were minimal and located at the peptide ends. In those cases, analysis of T cell polifunctionality and affinity indicated no differences with respect to the cellular responses found against the original homologous sequence. Significantly, application of a mixed immunization combining both clades (B and BF) induced a broader cellular response, in which the majority of the peptides targeted after the single clade vaccinations generated a positive response. In this group we could also find significant cellular and humoral responses against the whole gp120 protein from subtype B. Conclusions/Significance This work has characterized for the first time the immunogenic peptides of certain EnvBF regions, involved in T cell responses. It provides evidence that to improve immune responses to HIV there is a need to combine Env antigens from different clades, highlighting the convenience of the inclusion of BF antigens in future vaccines for geographic regions where these HIV variants circulate. PMID:21364754

  9. Poxvirus interleukin-4 expression overcomes inherent resistance and vaccine-induced immunity: pathogenesis, prophylaxis, and antiviral therapy.

    PubMed

    Chen, Nanhai; Bellone, Clifford J; Schriewer, Jill; Owens, Gelita; Fredrickson, Torgny; Parker, Scott; Buller, R Mark L

    2011-01-20

    In 2001, Jackson et al. reported that murine IL-4 expression by a recombinant ectromelia virus caused enhanced morbidity and lethality in resistant C57BL/6 mice as well as overcame protective immune memory responses. To achieve a more thorough understanding of this phenomenon and to assess a variety of countermeasures, we constructed a series of ECTV recombinants encoding murine IL-4 under the control of promoters of different strengths and temporal regulation. We showed that the ECTV-IL-4 recombinant expressing the highest level of IL-4 was uniformly lethal for C57BL/6 mice even when previously immunized. The lethality of the ECTV-IL-4 recombinants resulted from virus-expressed IL-4 signaling through the IL-4 receptor but was not due to IL-4 toxicity. A number of treatment approaches were evaluated against the most virulent IL-4 encoding virus. The most efficacious therapy was a combination of two antiviral drugs (CMX001(®) and ST-246(®)) that have different mechanisms of action. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Poxvirus interleukin-4 expression overcomes inherent resistance and vaccine-induced immunity: Pathogenesis, prophylaxis and antiviral therapy

    PubMed Central

    Chen, Nanhai; Bellone, Clifford J.; Schriewer, Jill; Owens, Gelita; Fredrickson, Torgny; Parker, Scott; Buller, R. Mark L.

    2010-01-01

    In 2001, Jackson et al. reported that murine IL-4 expression by a recombinant ectromelia virus caused enhanced morbidity and lethality in resistant C57BL/6 mice as well as overcame protective immune memory responses. To achieve a more thorough understanding of this phenomenon, and to asses a variety of countermeasures, we constructed a series of ECTV recombinants encoding murine IL-4 under the control of promoters of different strengths and temporal regulation. We showed that the ECTV-IL-4 recombinant expressing the highest level of IL-4 was uniformly lethal for C57BL/6 mice even when previously immunized. The lethality of the ECTV-IL-4 recombinants resulted from virus-expressed IL-4 signaling through the IL-4 receptor, but was not due to IL-4 toxicity. A number of treatment approaches were evaluated against the most virulent IL-4 encoding virus. The most efficacious therapy was a combination of two antiviral drugs (CMX001® and ST-246®) that have different mechanisms of action. PMID:21071055

  11. Multimodal evoked potentials in HIV-1-seropositive patients: relationship between the immune impairment and the neurophysiological function.

    PubMed

    Pierelli, F; Garrubba, C; Tilia, G; Parisi, L; Fattapposta, F; Pozzessere, G; Soldati, G; Stanzione, P; D'Offizi, G; Mezzaroma, I

    1996-04-01

    Multimodal evoked potentials (PRVEP, BAEP, mSEP) were recorded in 56 HIV-1 seropositive outpatients free from opportunistic CNS pathologies and/or overt HIV-1 encephalopathy. EPs were altered in 17 of 39 (43.6%) seropositive subjects without AIDS (group A) and in 13 of 17 (76.5%) patients with AIDS (group B). A high incidence of subclinical alterations (30.8%) were found in group A patients. Significant BAEP (I-III, III-V, I-V) interpeak latency and mSEP (N9-N13, N9-N20) conduction time prolongations were found in group A and B patients. PRVEP P100 was significantly prolonged only in group B. An inverse relationship between BAEP interpeak latencies and CD4 count was found. Our findings support the hypothesis of an important role of immunodepression in the development of neurophysiologic abnormalities, together with a preferential involvement of acoustic pathways, in the course of HIV-1 infection.

  12. Structural Basis of Immune Evasion at the Site of CD4 Attachment on HIV-1 gp120

    SciTech Connect

    Chen, Lei; Kwon, Young Do; Zhou, Tongqing; Wu, Xueling; O'Dell, Sijy; Cavacini, Lisa; Hessell, Ann J.; Pancera, Marie; Tang, Min; Xu, Ling; Yang, Zhi-Yong; Zhang, Mei-Yun; Arthos, James; Burton, Dennis R.; Dimitrov, Dimiter S.; Nabel, Gary J.; Posner, Marshall R.; Sodroski, Joseph; Wyatt, Richard; Mascola, John R.; Kwong, Peter D.

    2010-01-13

    The site on HIV-1 gp120 that binds to the CD4 receptor is vulnerable to antibodies. However, most antibodies that interact with this site cannot neutralize HIV-1. To understand the basis of this resistance, we determined co-crystal structures for two poorly neutralizing, CD4-binding site (CD4BS) antibodies, F105 and b13, in complexes with gp120. Both antibodies exhibited approach angles to gp120 similar to those of CD4 and a rare, broadly neutralizing CD4BS antibody, b12. Slight differences in recognition, however, resulted in substantial differences in F105- and b13-bound conformations relative to b12-bound gp120. Modeling and binding experiments revealed these conformations to be poorly compatible with the viral spike. This incompatibility, the consequence of slight differences in CD4BS recognition, renders HIV-1 resistant to all but the most accurately targeted antibodies.

  13. Reactivation of HIV-1 proviruses in immune-compromised mice engrafted with human VOA-negative CD4+ T cells.

    PubMed

    Yuan, Zhe; Kang, Guobin; Lu, Wuxun; Li, Qingsheng

    2017-01-01

    HIV-1 infection remains incurable on antiretroviral therapy (ART) due to virus latency. To date, enhanced co-culture assays, including viral outgrowth assays (VOA), are commonly used to measure HIV-1 latent reservoirs and evaluate latency-reversing agents (LRAs). However, VOA can only reactivate a small fraction of intact proviruses. To explore the utility of NOD scid gamma (NSG) mice as an in vivo model to reactivate HIV-1 proviruses from VOA-negative CD4+ T cells, resting CD4+ T cells from an HIV-1 latently infected individual were isolated and the human CD4+ T cells corresponding to VOA-positive and VOA-negative CD4+ T cells were engrafted into NSG mice. Plasma viral load (pVL) and human CD4+ T cells were quantified every other week using qRT-PCR and flow cytometry. We found that NSG mice reactivated latently infected HIV-1 from VOA-positive CD4+ T cells as well as VOA-negative CD4+ T cells. Engrafted CD4+ T cells proliferated considerably in vivo, peaked prior to provirus reactivation, and lasted for up to 14 weeks. Sequence analyses revealed that reactivated proviruses in VOA-positive and VOA-negative CD4+ T cells are different. Taken together, NSG mice can support long-term engraftment of human CD4+ T cells and reactivate VOA-positive and VOA-negative proviruses. Therefore, this in vivo model has the potential to be used to study the underlying mechanisms of HIV-1 latency and reactivation.

  14. Association of CMV-Specific T Cell-Mediated Immunity with CMV DNAemia and Development of CMV Disease in HIV-1-Infected Individuals.

    PubMed

    Aichelburg, Maximilian C; Weseslindtner, Lukas; Mandorfer, Mattias; Strassl, Robert; Rieger, Armin; Reiberger, Thomas; Puchhammer-Stöckl, Elisabeth; Grabmeier-Pfistershammer, Katharina

    2015-01-01

    Among HIV-1-infected individuals, cytomegalovirus (CMV) reactivation and disease occur in the setting of advanced immunosuppression. The value of a standardized assessment of CMV-specific T-cell mediated immunity by the CMV QuantiFERON assay (CMV-QFT) has not yet been thoroughly investigated in HIV-1-infected subjects. Prospective, longitudinal study in 153 HIV-1-infected subjects with a CD4+ T cell count < 350/μL who simultaneously underwent CMV-QFT, CMV serology testing and CMV-DNA quantification. Factors associated with CMV-QFT were evaluated. Clinical screening for CMV manifestations was then performed every 3 months. Among the 141 CMV IgG-seropositive individuals the CMV-QFT assay yielded reactive results in 84% (118/141), negative results in 15% (21/141) and indeterminate (negative mitogen IFN-gamma response) results in 1% (2/141) of subjects. The mean actual CD4+ T cell count was significantly higher in CMV-QFT reactive subjects, when compared to CMV-QFT non-reactive individuals (183 ± 102 vs. 126 ± 104 cells/μL, P = 0.015). A significantly lower proportion of CMV-QFT reactive vs. non-reactive patients displayed CMV DNAemia > 100 copies/mL (23% (27/118) vs. 48% (11/23), P = 0.02). Furthermore, a statistically significant inverse association between mitogen IFN-gamma response and CMV-DNAemia > 1000 copies/mL was observed (P < 0.001). During the observational period, 5 CMV end-organ manifestations were observed. In three of the CMV cases the CMV-QFT yielded indeterminate results. While CMV-QFT reactivity indicates CMV-specific immunity, indeterminate results due to negative mitogen IFN-gamma response might reflect HIV-1-induced immunodeficiency. Thus, dependency upon CD4+ T cell count should be considered when interpreting CMV-QFT results.

  15. Robust antigen-specific humoral immune responses to sublingually delivered adenoviral vectors encoding HIV-1 Env: association with mucoadhesion and efficient penetration of the sublingual barrier.

    PubMed

    Domm, William; Brooks, Lauren; Chung, Hung Li; Feng, Changyong; Bowers, William J; Watson, Gene; McGrath, James L; Dewhurst, Stephen

    2011-09-16

    The efficient induction of virus-specific mucosal antibodies is an important unmet objective in Human Immunodeficiency Virus Type-1 (HIV-1) vaccine research. One promising approach is sublingual (SL) immunization. We examined the effectiveness of SL delivery of two different viral vectors: (i) a recombinant adenovirus (rAd5), and (ii) a Herpes Simplex Virus Type-1 amplicon vector (HSV-1). Initial in vitro videomicroscopy experiments showed that rAd5 particles were trapped in saliva (i.e., that Ad5 was mucoadhesive) - unlike HSV-1 virions, which migrated freely in both saliva and water. In vivo imaging studies in mice revealed that only the rAd5 vector efficiently transduced the SL epithelium. Consistent with this, SL delivery of an rAd5 encoding HIV-1 envelope glycoprotein (Env) resulted in robust antigen-specific antibody responses in plasma and in vaginal washes, whereas SL delivery of a HSV-1 amplicon vector encoding HIV-1 Env failed to elicit Env-specific antibodies. In contrast, both vectors elicited equivalent humoral responses following intramuscular (IM) delivery. Finally, SL delivery of the rAd5:Env vector resulted in elevated levels of Env-specific serum IgA, and vaginal IgA and IgG, when compared to IM delivery of the same vector. These results findings shed light on vector properties (mucoadhesion, penetration of the sublingual barrier) which may be important for the induction of potent humoral immune responses following sublingual vector administration. Our data also show that SL delivery of an Env-encoding rAd5 vector can elicit a potent antigen-specific mucosal antibody response in the absence of adjuvant. Overall, these findings support the further exploration of the SL delivery route for HIV-1 vaccine delivery.

  16. Robust Antigen-Specific Humoral Immune Responses to Sublingually Delivered Adenoviral Vectors Encoding HIV-1 Env: Association with Mucoadhesion and Efficient Penetration of the Sublingual Barrier

    PubMed Central

    Domm, William; Brooks, Lauren; Chung, Hung Li; Feng, Changyong; Bowers, William J.; Watson, Gene; McGrath, James L.; Dewhurst, Stephen

    2011-01-01

    The efficient induction of virus-specific mucosal antibodies is an important unmet objective in Human Immunodeficiency Virus Type-1 (HIV-1) vaccine research. One promising approach is sublingual (SL) immunization. We examined the effectiveness of SL delivery of two different viral vectors: (i) a recombinant adenovirus (rAd5), and (ii) a Herpes Simplex Virus Type-1 amplicon vector (HSV-1). Initial in vitro videomicroscopy experiments showed that rAd5 particles were trapped in saliva (i.e., that Ad5 was mucoadhesive) - unlike HSV-1 virions, which migrated freely in both saliva and water. In vivo imaging studies in mice revealed that only the rAd5 vector efficiently transduced the SL epithelium. Consistent with this, SL delivery of an rAd5 encoding HIV-1 envelope glycoprotein (Env) resulted in robust antigen-specific antibody responses in plasma and in vaginal washes, whereas SL delivery of a HSV-1 amplicon vector encoding HIV-1 Env failed to elicit Env-specific antibodies. In contrast, both vectors elicited equivalent humoral responses following intramuscular (IM) delivery. Finally, SL delivery of the rAd5:Env vector resulted in elevated levels of Env-specific serum IgA, and vaginal IgA and IgG, when compared to IM delivery of the same vector. These results findings shed light on vector properties (mucoadhesion, penetration of the sublingual barrier) which may be important for the induction of potent humoral immune responses following sublingual vector administration. Our data also show that SL delivery of an Env-encoding rAd5 vector can elicit a potent antigen-specific mucosal antibody response in the absence of adjuvant. Overall, these findings support the further exploration of the SL delivery route for HIV-1 vaccine delivery. PMID:21801777

  17. The genome of Yoka poxvirus.

    PubMed

    Zhao, Guoyan; Droit, Lindsay; Tesh, Robert B; Popov, Vsevolod L; Little, Nicole S; Upton, Chris; Virgin, Herbert W; Wang, David

    2011-10-01

    Yoka poxvirus was isolated almost four decades ago from a mosquito pool in the Central African Republic. Its classification as a poxvirus is based solely upon the morphology of virions visualized by electron microscopy. Here we describe sequencing of the Yoka poxvirus genome using a combination of Roche/454 and Illumina next-generation sequencing technologies. A single consensus contig of ∼175 kb in length that encodes 186 predicted genes was generated. Multiple methods were used to show that Yoka poxvirus is most closely related to viruses in the Orthopoxvirus genus, but it is clearly distinct from previously described poxviruses. Collectively, the phylogenetic and genomic sequence analyses suggest that Yoka poxvirus is the prototype member of a new genus in the family Poxviridae.

  18. HIV-1 Vpu Blocks Recycling and Biosynthetic Transport of the Intrinsic Immunity Factor CD317/Tetherin To Overcome the Virion Release Restriction

    PubMed Central

    Schmidt, Sarah; Fritz, Joëlle V.; Bitzegeio, Julia; Fackler, Oliver T.; Keppler, Oliver T.

    2011-01-01

    ABSTRACT The intrinsic immunity factor CD317 (BST-2/HM1.24/tetherin) imposes a barrier to HIV-1 release at the cell surface that can be overcome by the viral protein Vpu. Expression of Vpu results in a reduction of CD317 surface levels; however, the mechanism of this Vpu activity and its contribution to the virological antagonism are incompletely understood. Here, we characterized the influence of Vpu on major CD317 trafficking pathways using quantitative antibody-based endocytosis and recycling assays as well as a microinjection/microscopy-based kinetic de novo expression approach. We report that HIV-1 Vpu inhibited both the anterograde transport of newly synthesized CD317 and the recycling of CD317 to the cell surface, while the kinetics of CD317 endocytosis remained unaffected. Vpu trapped trafficking CD317 molecules at the trans-Golgi network, where the two molecules colocalized. The subversion of both CD317 transport pathways was dependent on the highly conserved diserine S52/S56 motif of Vpu; however, it did not require recruitment of the diserine motif interactor and substrate adaptor of the SCF-E3 ubiquitin ligase complex, β-TrCP. Treatment of cells with the malaria drug primaquine resulted in a CD317 trafficking defect that mirrored that induced by Vpu. Importantly, primaquine could functionally replace Vpu as a CD317 antagonist and rescue HIV-1 particle release. PMID:21610122

  19. The Evolutionary Biology of Poxviruses

    PubMed Central

    Hughes, Austin L.; Irausquin, Stephanie; Friedman, Robert

    2009-01-01

    The poxviruses (family Poxviridae) are a family of double-stranded viruses including several species that infect humans and their domestic animals, most notably Variola virus (VARV), the causative agent of smallpox. The evolutionary biology of these viruses poses numerous questions, for which we have only partial answers at present. Here we review evidence regarding the origin of poxviruses, the frequency of host transfer in poxvirus history, horizontal transfer of host genes to poxviruses, and the population processes accounting for patterns of nucleotide sequence polymorphism. PMID:19833230

  20. Immunogenicity of HIV-1 IIIB and SHIV 89.6P Tat and Tat toxoids in rhesus macaques: induction of humoral and cellular immune responses.

    PubMed

    Richardson, Max W; Mirchandani, Jyotika; Silvera, Peter; Régulier, Emmanuel G; Capini, Christelle; Bojczuk, Paul M; Hu, Jason; Gracely, Edward J; Boyer, Jean D; Khalili, Kamel; Zagury, Jean-François; Lewis, Mark G; Rappaport, Jay

    2002-09-01

    This study compared immune responses in rhesus macaques immunized with unmodified HIV-1 IIIB Tat, SHIV89.6P Tat, and carboxymethylated IIIB and 89.6P Tat toxoids. Immunization with either IIIB or 89.6P preparation induced high titer and broadly crossreactive serum anti-Tat IgG that recognized HIV-1 subtype-E and SIVmac251 Tat. However, the response was delayed, and titers were lower in 89.6P vaccination groups. Serum anti-Tat IgG recognized peptides corresponding to the amino-terminus, basic domain, and carboxy-terminal region. Cellular proliferative responses to Tat toxoids corresponding to the immunogen were evident in vitro in both IIIB and 89.6P groups. Crossreactive proliferative responses were observed in IIIB groups in response to stimulation with 89.6P or SIVmac251 Tat toxoids, but were much less prevalent in 89.6P groups. The truncated 86 amino acid IIIB Tat appears to be more immunogenic than the 102 amino acid 89.6P Tat with respect to both humoral and cellular immune responses, and may be a better vaccine component. Despite induction of robust humoral and cellular immune responses (including both CD4+ and CD8+ T-cell responses) to Tat, all animals were infected upon intravenous challenge with 30 MID(50) of SHIV89.6P and outcome of vaccine groups was not different from controls. Sequencing both Tat exons from serum viral RNA revealed no evidence of escape mutants. These results suggest that with intravenous SHIV89.6P challenge in rhesus macaques, precipitous CD4+ T-cell decline overwhelms potentially protective immune responses. Alternatively, Tat specific CD8+ T-cell responses may not appropriately recognize infected cells in vivo in this model. In view of evidence demonstrating Tat specific CTLs in the SIV model and in humans infected with HIV-1, results in this pathogenic SHIV model may not apparently predict the efficacy of this approach in human studies. The potency and cross-reactivity of these immune responses confirm Tat toxoid as an excellent

  1. Induction of multi-antigen multi-stage immune responses against Plasmodium falciparum in rhesus monkeys, in the absence of antigen interference, with heterologous DNA prime/poxvirus boost immunization

    PubMed Central

    Jiang, George; Charoenvit, Yupin; Moreno, Alberto; Baraceros, Maria F; Banania, Glenna; Richie, Nancy; Abot, Steve; Ganeshan, Harini; Fallarme, Victoria; Patterson, Noelle B; Geall, Andrew; Weiss, Walter R; Strobert, Elizabeth; Caro-Aquilar, Ivette; Lanar, David E; Saul, Allan; Martin, Laura B; Gowda, Kalpana; Morrissette, Craig R; Kaslow, David C; Carucci, Daniel J; Galinski, Mary R; Doolan, Denise L

    2007-01-01

    The present study has evaluated the immunogenicity of single or multiple Plasmodium falciparum (Pf) antigens administered in a DNA prime/poxvirus boost regimen with or without the poloxamer CRL1005 in rhesus monkeys. Animals were primed with PfCSP plasmid DNA or a mixture of PfCSP, PfSSP2/TRAP, PfLSA1, PfAMA1 and PfMSP1-42 (CSLAM) DNA vaccines in PBS or formulated with CRL1005, and subsequently boosted with ALVAC-Pf7, a canarypox virus expressing the CSLAM antigens. Cell-mediated immune responses were evaluated by IFN-γ ELIspot and intracellular cytokine staining, using recombinant proteins and overlapping synthetic peptides. Antigen-specific and parasite-specific antibody responses were evaluated by ELISA and IFAT, respectively. Immune responses to all components of the multi-antigen mixture were demonstrated following immunization with either DNA/PBS or DNA/CRL1005, and no antigen interference was observed in animals receiving CSLAM as compared to PfCSP alone. These data support the down-selection of the CSLAM antigen combination. CRL1005 formulation had no apparent effect on vaccine-induced T cell or antibody responses, either before or after viral boost. In high responder monkeys, CD4+IL-2+ responses were more predominant than CD8+ T cell responses. Furthermore, CD8+ IFN-γ responses were detected only in the presence of detectable CD4+ T cell responses. Overall, this study demonstrates the potential for multivalent Pf vaccines based on rational antigen selection and combination, and suggests that further formulation development to increase the immunogenicity of DNA encoded antigens is warranted. PMID:17925026

  2. Poxvirus-Induced Immunostimulating Effects on Porcine Leukocytes

    PubMed Central

    Fachinger, Vicky; Schlapp, Tobias; Strube, Walter; Schmeer, Norbert; Saalmüller, Armin

    2000-01-01

    The prophylactic application of inactivated parapox ovis viruses (Baypamun; Bayer AG, Leverkusen, Germany) has been shown to reduce efficiently the outbreak of stress-mediated diseases in different species. However, little is known about the basic mechanism behind this observed stimulatory property. We therefore tested eight inactivated poxvirus strains belonging to three different genera (Orthopoxvirus, Avipoxvirus, and Parapoxvirus) for their capacity to activate cells of the porcine innate and specific immune systems in vitro. The results indicated that poxviruses failed to induce increased phagocytosis, oxidative burst, or natural killer cell activity in swine. In contrast, enhanced release of interleukin-2, alpha interferon, and gamma interferon, as well as strong proliferation, could be measured. Flow cytometric analyses and cell sorting experiments identified T-helper cells as the main target responding to inactivated poxviruses: the activated cells had a CD4high CD25+ major histocompatibility complex type II-positive phenotype and were the major source of secreted cytokines. Together, the results demonstrated that all tested poxviruses possessed immunostimulating capacity. These in vitro poxvirus-induced effects may be responsible at least in part for the in vivo immunostimulating capacity of inactivated poxviruses. PMID:10933702

  3. Poxvirus-induced immunostimulating effects on porcine leukocytes.

    PubMed

    Fachinger, V; Schlapp, T; Strube, W; Schmeer, N; Saalmüller, A

    2000-09-01

    The prophylactic application of inactivated parapox ovis viruses (Baypamun; Bayer AG, Leverkusen, Germany) has been shown to reduce efficiently the outbreak of stress-mediated diseases in different species. However, little is known about the basic mechanism behind this observed stimulatory property. We therefore tested eight inactivated poxvirus strains belonging to three different genera (Orthopoxvirus, Avipoxvirus, and Parapoxvirus) for their capacity to activate cells of the porcine innate and specific immune systems in vitro. The results indicated that poxviruses failed to induce increased phagocytosis, oxidative burst, or natural killer cell activity in swine. In contrast, enhanced release of interleukin-2, alpha interferon, and gamma interferon, as well as strong proliferation, could be measured. Flow cytometric analyses and cell sorting experiments identified T-helper cells as the main target responding to inactivated poxviruses: the activated cells had a CD4(high) CD25(+) major histocompatibility complex type II-positive phenotype and were the major source of secreted cytokines. Together, the results demonstrated that all tested poxviruses possessed immunostimulating capacity. These in vitro poxvirus-induced effects may be responsible at least in part for the in vivo immunostimulating capacity of inactivated poxviruses.

  4. Nedd4-Mediated Increase in HIV-1 Gag and Env Proteins and Immunity following DNA-Vaccination of BALB/c Mice

    PubMed Central

    Lewis, Brad; Whitney, Stephen; Hudacik, Lauren; Galmin, Lindsey; Huaman, Maria Cecilia; Cristillo, Anthony D.

    2014-01-01

    The late assembly domain of many viruses is critical for budding. Within these domains, encoded in viral structural proteins, are the conserved motifs PTAP, PPxY and YPxL. These sequences are the key determinants for association of viral proteins with intracellular molecules such as Tsg101, Nedd4 and AIP1/ALIX. While roles for Tsg101 and AIP1/ALIX in HIV-1 budding have been well established, less is known about the role of Nedd4. Recent studies, however, have identified a function for Nedd4-like protein in HIV-1 release. In this study, we investigated post-transcriptional changes of Nedd4 following SHIVSF162P3 infection of rhesus macaques, its role on HIV-1 p24 and gp120 levels in vitro and its potential as an immune modulator in HIV vaccination of BALB/c mice. Increased Nedd4 protein levels were noted in both CD4+ and CD8+ T cells following SHIVSF162P3-infection of naïve macaques. Transient co-transfection studies in 293 cells with HXB2 and Nedd4 demonstrated a Nedd4-mediated increase in p24 and gp120 levels. This increase was found to be dependent on the Ca2+/calmodulin-regulated phospholipid binding C2 domain and not ubiquitin ligase activity or HIV LTR activity. Co-transfection of Nedd4 with plasmid DNA expressing Gag or Env was further shown to augment both intracellular and extracellular Gag or Env proteins. To assess the potential of Nedd4 as an immune modulator, BALB/c mice were immunized intramuscularly with plasmid DNA encoding HIV gag, env and Nedd4. Nedd4 co-administration was found to increase serum anti-p24 but not anti-gp120 antibodies. Nedd4 co-injection was found to have no affect on Gag- or Env-specific IFNγ but had a trend of increased Gag-specific IL-6, IL-17A and TNFα that was not seen following Env stimulation. Based on our initial findings, Nedd4-mediated changes in HIV protein levels and its potential use in HIV-1 vaccine development warrants further investigation. PMID:24614057

  5. Nedd4-mediated increase in HIV-1 Gag and Env proteins and immunity following DNA-vaccination of BALB/c mice.

    PubMed

    Lewis, Brad; Whitney, Stephen; Hudacik, Lauren; Galmin, Lindsey; Huaman, Maria Cecilia; Cristillo, Anthony D

    2014-01-01

    The late assembly domain of many viruses is critical for budding. Within these domains, encoded in viral structural proteins, are the conserved motifs PTAP, PPxY and YPxL. These sequences are the key determinants for association of viral proteins with intracellular molecules such as Tsg101, Nedd4 and AIP1/ALIX. While roles for Tsg101 and AIP1/ALIX in HIV-1 budding have been well established, less is known about the role of Nedd4. Recent studies, however, have identified a function for Nedd4-like protein in HIV-1 release. In this study, we investigated post-transcriptional changes of Nedd4 following SHIVSF162P3 infection of rhesus macaques, its role on HIV-1 p24 and gp120 levels in vitro and its potential as an immune modulator in HIV vaccination of BALB/c mice. Increased Nedd4 protein levels were noted in both CD4+ and CD8+ T cells following SHIVSF162P3-infection of naïve macaques. Transient co-transfection studies in 293 cells with HXB2 and Nedd4 demonstrated a Nedd4-mediated increase in p24 and gp120 levels. This increase was found to be dependent on the Ca2+/calmodulin-regulated phospholipid binding C2 domain and not ubiquitin ligase activity or HIV LTR activity. Co-transfection of Nedd4 with plasmid DNA expressing Gag or Env was further shown to augment both intracellular and extracellular Gag or Env proteins. To assess the potential of Nedd4 as an immune modulator, BALB/c mice were immunized intramuscularly with plasmid DNA encoding HIV gag, env and Nedd4. Nedd4 co-administration was found to increase serum anti-p24 but not anti-gp120 antibodies. Nedd4 co-injection was found to have no affect on Gag- or Env-specific IFNγ but had a trend of increased Gag-specific IL-6, IL-17A and TNFα that was not seen following Env stimulation. Based on our initial findings, Nedd4-mediated changes in HIV protein levels and its potential use in HIV-1 vaccine development warrants further investigation.

  6. Depot Medroxyprogesterone Acetate (DMPA) Use is Associated with Elevated Innate Immune Effector Molecules in Cervicovaginal Secretions of HIV-1-uninfected Women

    PubMed Central

    Guthrie, Brandon L.; Introini, Andrea; Roxby, Alison C.; Choi, Robert Y.; Bosire, Rose; Lohman-Payne, Barbara; Hirbod, Taha; Farquhar, Carey; Broliden, Kristina

    2015-01-01

    OBJECTIVE The effects of sex hormones on the immune defenses of the female genital mucosa and its susceptibility to infections are poorly understood. The injectable hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may increase risk of HIV-1 acquisition. We assessed the local concentration in the female genital mucosa of cationic polypeptides with reported antiviral activity in relation to DMPA use. METHODS HIV-1-uninfected women were recruited from among couples testing for HIV in Nairobi, Kenya. Cervicovaginal secretion (CVS) samples were collected and the concentrations of HNP1–3, LL-37, lactoferrin, HBD-2 and SLPI were measured by enzyme-linked immunosorbent assays.. Levels of cationic polypeptides in CVS were compared between women who were not using hormonal contraception and those using DMPA, oral, or implantable contraception. RESULTS Among 228 women, 165 (72%) reported not using hormonal contraception at enrollment, 41 (18%) used DMPA, 16 (7%) used an oral contraceptive, and 6 (3%) used a contraceptive implant. Compared to non-users of hormonal contraception, DMPA users had significantly higher mean levels of HNP1–3 (2.38 vs. 2.04 log10 ng/ml; p=0.024), LL-37 (0.81 vs. 0.40 log10 ng/ml; p=0.027), and lactoferrin (3.03 vs. 2.60 log10 ng/ml; p=0.002), whereas SLPI and HBD-2 were similar. CONCLUSIONS Although all analyzed cationic polypeptides have intrinsic antiviral capacity, their interaction and cumulative effect on female genital mucosa susceptibility to infections in vivo has yet to be unraveled. This study suggests a potential mechanism underlying the effect of DMPA on the innate immune defenses, providing a rationale to investigate its effect on HIV-1 acquisition risk. PMID:25622059

  7. [Poxvirus infection in a cat].

    PubMed

    Ballauf, B; Linckh, S; Lechner, J

    1989-01-01

    For the first time, a poxvirus infection was diagnosed as an etiologic agent of dermal disease in a living domestic cat in Germany. A literature survey, the clinical symptoms of the infection and the diagnostic procedures are described. Poxvirus infections should be considered as a differential diagnosis in feline dermatologic problems.

  8. Low Double-Negative CD3(+)CD4(-)CD8(-) T Cells Are Associated with Incomplete Restoration of CD4(+) T Cells and Higher Immune Activation in HIV-1 Immunological Non-Responders.

    PubMed

    Lu, Xiaofan; Su, Bin; Xia, Huan; Zhang, Xin; Liu, Zhiying; Ji, Yunxia; Yang, Zixuan; Dai, Lili; Mayr, Luzia M; Moog, Christiane; Wu, Hao; Huang, Xiaojie; Zhang, Tong

    2016-01-01

    Failure of immune reconstitution increases the risk of AIDS or non-AIDS related morbidity and mortality in HIV-1-infected patients. CD3(+)CD4(-)CD8(-) T cells, which are usually described as double-negative (DN) T cells, display CD4-like helper and immunoregulatory functions. Here, we have measured the percentage of DN T cells in the immune reconstituted vs. non-immune reconstituted HIV-1-infected individuals. We observed that immunological non-responders (INRs) had a low number of DN T cells after long-term antiretroviral therapy (ART), and the number of these cells positively correlated with the CD4(+) T cell count. The ART did not result in complete suppression of immune activation recorded by the percentage of CD38(+)HLA-DR(+)CD8(+) T cells in INRs, and a strong inverse correlation was observed between DN T cells and immune activation. A low proportion of TGF-β1(+)DN T cells was found in INRs. Further mechanism study demonstrated that the level of TGF-β1-producing DN T cells and immune activation had a negative correlation after ART. Taken together, our study suggests that DN T cells control the immunological response in HIV-1-infected patients. These findings expand our understanding of the mechanism of immune reconstitution and could develop specific treatments to return the immune system to homeostasis following initiation of HIV-1 therapy.

  9. Low Double-Negative CD3+CD4−CD8− T Cells Are Associated with Incomplete Restoration of CD4+ T Cells and Higher Immune Activation in HIV-1 Immunological Non-Responders

    PubMed Central

    Lu, Xiaofan; Su, Bin; Xia, Huan; Zhang, Xin; Liu, Zhiying; Ji, Yunxia; Yang, Zixuan; Dai, Lili; Mayr, Luzia M.; Moog, Christiane; Wu, Hao; Huang, Xiaojie; Zhang, Tong

    2016-01-01

    Failure of immune reconstitution increases the risk of AIDS or non-AIDS related morbidity and mortality in HIV-1-infected patients. CD3+CD4−CD8− T cells, which are usually described as double-negative (DN) T cells, display CD4-like helper and immunoregulatory functions. Here, we have measured the percentage of DN T cells in the immune reconstituted vs. non-immune reconstituted HIV-1-infected individuals. We observed that immunological non-responders (INRs) had a low number of DN T cells after long-term antiretroviral therapy (ART), and the number of these cells positively correlated with the CD4+ T cell count. The ART did not result in complete suppression of immune activation recorded by the percentage of CD38+HLA-DR+CD8+ T cells in INRs, and a strong inverse correlation was observed between DN T cells and immune activation. A low proportion of TGF-β1+DN T cells was found in INRs. Further mechanism study demonstrated that the level of TGF-β1-producing DN T cells and immune activation had a negative correlation after ART. Taken together, our study suggests that DN T cells control the immunological response in HIV-1-infected patients. These findings expand our understanding of the mechanism of immune reconstitution and could develop specific treatments to return the immune system to homeostasis following initiation of HIV-1 therapy. PMID:28018346

  10. HIV-1 adenoviral vector vaccines expressing multi-trimeric BAFF and 4-1BBL enhance T cell mediated anti-viral immunity.

    PubMed

    Kanagavelu, Saravana; Termini, James M; Gupta, Sachin; Raffa, Francesca N; Fuller, Katherine A; Rivas, Yaelis; Philip, Sakhi; Kornbluth, Richard S; Stone, Geoffrey W

    2014-01-01

    Adenoviral vectored vaccines have shown considerable promise but could be improved by molecular adjuvants. Ligands in the TNF superfamily (TNFSF) are potential adjuvants for adenoviral vector (Ad5) vaccines based on their central role in adaptive immunity. Many TNFSF ligands require aggregation beyond the trimeric state (multi-trimerization) for optimal biological function. Here we describe Ad5 vaccines for HIV-1 Gag antigen (Ad5-Gag) adjuvanted with the TNFSF ligands 4-1BBL, BAFF, GITRL and CD27L constructed as soluble multi-trimeric proteins via fusion to Surfactant Protein D (SP-D) as a multimerization scaffold. Mice were vaccinated with Ad5-Gag combined with Ad5 expressing one of the SP-D-TNFSF constructs or single-chain IL-12p70 as adjuvant. To evaluate vaccine-induced protection, mice were challenged with vaccinia virus expressing Gag (vaccinia-Gag) which is known to target the female genital tract, a major route of sexually acquired HIV-1 infection. In this system, SP-D-4-1BBL or SP-D-BAFF led to significantly reduced vaccinia-Gag replication when compared to Ad5-Gag alone. In contrast, IL-12p70, SP-D-CD27L and SP-D-GITRL were not protective. Histological examination following vaccinia-Gag challenge showed a dramatic lymphocytic infiltration into the uterus and ovaries of SP-D-4-1BBL and SP-D-BAFF-treated animals. By day 5 post challenge, proinflammatory cytokines in the tissue were reduced, consistent with the enhanced control over viral replication. Splenocytes had no specific immune markers that correlated with protection induced by SP-D-4-1BBL and SP-D-BAFF versus other groups. IL-12p70, despite lack of anti-viral efficacy, increased the total numbers of splenic dextramer positive CD8+ T cells, effector memory T cells, and effector Gag-specific CD8+ T cells, suggesting that these markers are poor predictors of anti-viral immunity in this model. In conclusion, soluble multi-trimeric 4-1BBL and BAFF adjuvants led to strong protection from vaccinia

  11. Poxvirus DNA Replication

    PubMed Central

    Moss, Bernard

    2013-01-01

    Poxviruses are large, enveloped viruses that replicate in the cytoplasm and encode proteins for DNA replication and gene expression. Hairpin ends link the two strands of the linear, double-stranded DNA genome. Viral proteins involved in DNA synthesis include a 117-kDa polymerase, a helicase–primase, a uracil DNA glycosylase, a processivity factor, a single-stranded DNA-binding protein, a protein kinase, and a DNA ligase. A viral FEN1 family protein participates in double-strand break repair. The DNA is replicated as long concatemers that are resolved by a viral Holliday junction endonuclease. PMID:23838441

  12. Priming Immunization with DNA Augments Immunogenicity of Recombinant Adenoviral Vectors for Both HIV-1 Specific Antibody and T-Cell Responses

    PubMed Central

    Koup, Richard A.; Roederer, Mario; Lamoreaux, Laurie; Fischer, Jennifer; Novik, Laura; Nason, Martha C.; Larkin, Brenda D.; Enama, Mary E.; Ledgerwood, Julie E.; Bailer, Robert T.; Mascola, John R.; Nabel, Gary J.; Graham, Barney S.

    2010-01-01

    Background Induction of HIV-1-specific T-cell responses relevant to diverse subtypes is a major goal of HIV vaccine development. Prime-boost regimens using heterologous gene-based vaccine vectors have induced potent, polyfunctional T cell responses in preclinical studies. Methods The first opportunity to evaluate the immunogenicity of DNA priming followed by recombinant adenovirus serotype 5 (rAd5) boosting was as open-label rollover trials in subjects who had been enrolled in prior studies of HIV-1 specific DNA vaccines. All subjects underwent apheresis before and after rAd5 boosting to characterize in depth the T cell and antibody response induced by the heterologous DNA/rAd5 prime-boost combination. Results rAd5 boosting was well-tolerated with no serious adverse events. Compared to DNA or rAd5 vaccine alone, sequential DNA/rAd5 administration induced 7-fold higher magnitude Env-biased HIV-1-specific CD8+ T-cell responses and 100-fold greater antibody titers measured by ELISA. There was no significant neutralizing antibody activity against primary isolates. Vaccine-elicited CD4+ and CD8+ T-cells expressed multiple functions and were predominantly long-term (CD127+) central or effector memory T cells and that persisted in blood for >6 months. Epitopes mapped in Gag and Env demonstrated partial cross-clade recognition. Conclusion Heterologous prime-boost using vector-based gene delivery of vaccine antigens is a potent immunization strategy for inducing both antibody and T-cell responses. Trial Registration ClinicalTrails.gov NCT00102089, NCT00108654 PMID:20126394

  13. Therapeutic Immunization with HIV-1 Tat Reduces Immune Activation and Loss of Regulatory T-Cells and Improves Immune Function in Subjects on HAART

    PubMed Central

    Ensoli, Barbara; Bellino, Stefania; Tripiciano, Antonella; Longo, Olimpia; Francavilla, Vittorio; Marcotullio, Simone; Cafaro, Aurelio; Picconi, Orietta; Paniccia, Giovanni; Scoglio, Arianna; Arancio, Angela; Ariola, Cristina; Ruiz Alvarez, Maria J.; Campagna, Massimo; Scaramuzzi, Donato; Iori, Cristina; Esposito, Roberto; Mussini, Cristina; Ghinelli, Florio; Sighinolfi, Laura; Palamara, Guido; Latini, Alessandra; Angarano, Gioacchino; Ladisa, Nicoletta; Soscia, Fabrizio; Mercurio, Vito S.; Lazzarin, Adriano; Tambussi, Giuseppe; Visintini, Raffaele; Mazzotta, Francesco; Di Pietro, Massimo; Galli, Massimo; Rusconi, Stefano; Carosi, Giampiero; Torti, Carlo; Di Perri, Giovanni; Bonora, Stefano; Ensoli, Fabrizio; Garaci, Enrico

    2010-01-01

    Although HAART suppresses HIV replication, it is often unable to restore immune homeostasis. Consequently, non-AIDS-defining diseases are increasingly seen in treated individuals. This is attributed to persistent virus expression in reservoirs and to cell activation. Of note, in CD4+ T cells and monocyte-macrophages of virologically-suppressed individuals, there is continued expression of multi-spliced transcripts encoding HIV regulatory proteins. Among them, Tat is essential for virus gene expression and replication, either in primary infection or for virus reactivation during HAART, when Tat is expressed, released extracellularly and exerts, on both the virus and the immune system, effects that contribute to disease maintenance. Here we report results of an ad hoc exploratory interim analysis (up to 48 weeks) on 87 virologically-suppressed HAART-treated individuals enrolled in a phase II randomized open-label multicentric clinical trial of therapeutic immunization with Tat (ISS T-002). Eighty-eight virologically-suppressed HAART-treated individuals, enrolled in a parallel prospective observational study at the same sites (ISS OBS T-002), served for intergroup comparison. Immunization with Tat was safe, induced durable immune responses, and modified the pattern of CD4+ and CD8+ cellular activation (CD38 and HLA-DR) together with reduction of biochemical activation markers and persistent increases of regulatory T cells. This was accompanied by a progressive increment of CD4+ T cells and B cells with reduction of CD8+ T cells and NK cells, which were independent from the type of antiretroviral regimen. Increase in central and effector memory and reduction in terminally-differentiated effector memory CD4+ and CD8+ T cells were accompanied by increases of CD4+ and CD8+ T cell responses against Env and recall antigens. Of note, more immune-compromised individuals experienced greater therapeutic effects. In contrast, these changes were opposite, absent or partial in the

  14. Immunization with Recombinant HLA Classes I and II, HIV-1 gp140, and SIV p27 Elicits Protection against Heterologous SHIV Infection in Rhesus Macaques▿†

    PubMed Central

    Mörner, Andreas; Jansson, Marianne; Bunnik, Evelien M.; Schøller, Jørgen; Vaughan, Robert; Wang, Yufei; Montefiori, David C.; Otting, Nel; Bontrop, Ronald; Bergmeier, Lesley A.; Singh, Mahavir; Wyatt, Richard T.; Schuitemaker, Hanneke; Biberfeld, Gunnel; Thorstensson, Rigmor; Lehner, Thomas

    2011-01-01

    Major histocompatibility complex (MHC) molecules expressed on the surface of human immunodeficiency virus (HIV) are potential targets for neutralizing antibodies. Since MHC molecules are polymorphic, nonself MHC can also be immunogenic. We have used combinations of novel recombinant HLA class I and II and HIV/simian immunodeficiency virus (SIV) antigens, all linked to dextran, to investigate whether they can elicit protective immunity against heterologous simian/human immunodeficiency virus (SHIV) challenge in rhesus macaques. Three groups of animals were immunized with HLA (group 1, n = 8), trimeric YU2 HIV type 1 (HIV-1) gp140 and SIV p27 (HIV/SIV antigens; group 2, n = 8), or HLA plus HIV/SIV antigens (group 3, n = 8), all with Hsp70 and TiterMax Gold adjuvant. Another group (group 4, n = 6) received the same vaccine as group 3 without TiterMax Gold. Two of eight macaques in group 3 were completely protected against intravenous challenge with 18 50% animal infective doses (AID50) of SHIV-SF162P4/C grown in human cells expressing HLA class I and II lineages represented in the vaccine, while the remaining six macaques showed decreased viral loads compared to those in unimmunized animals. Complement-dependent neutralizing activity in serum and high levels of anti-HLA antibodies were elicited in groups 1 and 3, and both were inversely correlated with the plasma viral load at 2 weeks postchallenge. Antibody-mediated protection was strongly supported by the fact that transfer of pooled serum from the two challenged but uninfected animals protected two naïve animals against repeated low-dose challenge with the same SHIV stock. This study demonstrates that immunization with recombinant HLA in combination with HIV-1 antigens might be developed into an alternative strategy for a future AIDS vaccine. PMID:21490092

  15. Neopterin and Soluble CD14 Levels as Indicators of Immune Activation in Cases with Indeterminate Pattern and True Positive HIV-1 Infection.

    PubMed

    Uysal, Hayriye Kırkoyun; Sohrabi, Pari; Habip, Zafer; Saribas, Suat; Kocazeybek, Emre; Seyhan, Fatih; Calışkan, Reyhan; Bonabi, Esad; Yuksel, Pelin; Birinci, Ilhan; Uysal, Omer; Kocazeybek, Bekir

    2016-01-01

    We aimed to evaluate the roles of the plasma immune activation biomarkers neopterin and soluble CD14 (sCD14) in the indirect assessment of the immune activation status of patients with the indeterminate HIV-1 (IHIV-1) pattern and a true HIV-1-positive infection (PCG). This cross-sectional and descriptive study included eighty-eight patients with the IHIV-1 pattern, 100 patients in the PCG, and 100 people in a healthy control group (HCG). Neopterin and sCD14 levels were determined by competitive and sandwich ELISA methods, respectively. Mean neopterin and sCD14 levels among those with the IHIV-1 pattern were significantly lower than among the PCG (p < 0.001 and p = 0.001, respectively), but they were similiar to those in the HCG (p = 0.57 and p = 0.66, respectively. Mean neopterin and sCD14 levels among the PCG were found to be significantly higher than among those with the IHIV-1 pattern (p < 0.001 and p = 0.001, respectively) and among those in the HCG (p = 0.001, p < 0.001, respectively). Neopterin did not have adequate predictive value for identifying those in the PCG (area under the curve [AUC] = 0.534; 95% CI, 0.463-0.605; p = 0.4256); sCD14 also had poor predictive value but high specificity (100%) for identifying those in the PCG (AUC = 0.627; 95% CI, 0.556-0.694; p = 0.0036). While low levels of these two biomarkers were detected among those with the IHIV-1 pattern, they were found in high levels among those in the PCG. These two markers obviously cannot be used as a sceening test because they have low sensitivies. Taken together, we suggest that neopterin and sCD14 may be helpful because they both have high specificity (92%-100%) as indirect non-specific markers for predicting the immune activation status of individuals, whether or not they have true positive HIV-1.

  16. Neopterin and Soluble CD14 Levels as Indicators of Immune Activation in Cases with Indeterminate Pattern and True Positive HIV-1 Infection

    PubMed Central

    Uysal, Hayriye Kırkoyun; Sohrabi, Pari; Habip, Zafer; Saribas, Suat; Kocazeybek, Emre; Seyhan, Fatih; Calışkan, Reyhan; Bonabi, Esad; Yuksel, Pelin; Birinci, Ilhan; Uysal, Omer; Kocazeybek, Bekir

    2016-01-01

    Background We aimed to evaluate the roles of the plasma immune activation biomarkers neopterin and soluble CD14 (sCD14) in the indirect assessment of the immune activation status of patients with the indeterminate HIV-1 (IHIV-1) pattern and a true HIV-1-positive infection (PCG). Methods This cross-sectional and descriptive study included eighty-eight patients with the IHIV-1 pattern, 100 patients in the PCG, and 100 people in a healthy control group (HCG). Neopterin and sCD14 levels were determined by competitive and sandwich ELISA methods, respectively. Results Mean neopterin and sCD14 levels among those with the IHIV-1 pattern were significantly lower than among the PCG (p < 0.001 and p = 0.001, respectively), but they were similiar to those in the HCG (p = 0.57 and p = 0.66, respectively. Mean neopterin and sCD14 levels among the PCG were found to be significantly higher than among those with the IHIV-1 pattern (p < 0.001 and p = 0.001, respectively) and among those in the HCG (p = 0.001, p < 0.001, respectively). Neopterin did not have adequate predictive value for identifying those in the PCG (area under the curve [AUC] = 0.534; 95% CI, 0.463–0.605; p = 0.4256); sCD14 also had poor predictive value but high specificity (100%) for identifying those in the PCG (AUC = 0.627; 95% CI, 0.556–0.694; p = 0.0036). Conclusions While low levels of these two biomarkers were detected among those with the IHIV-1 pattern, they were found in high levels among those in the PCG. These two markers obviously cannot be used as a sceening test because they have low sensitivies. Taken together, we suggest that neopterin and sCD14 may be helpful because they both have high specificity (92%-100%) as indirect non-specific markers for predicting the immune activation status of individuals, whether or not they have true positive HIV-1. PMID:27031691

  17. Vaginal delivery of the recombinant HIV-1 clade-C trimeric gp140 envelope protein CN54gp140 within novel rheologically structured vehicles elicits specific immune responses

    PubMed Central

    Curran, Rhonda M.; Donnelly, Louise; Morrow, Ryan J.; Fraser, Carol; Andrews, Gavin; Cranage, Martin; Malcolm, R. Karl; Shattock, Robin J.; Woolfson, A. David

    2009-01-01

    Rheologically structured vehicle (RSV) gels were developed as delivery systems for vaginal mucosal vaccination with an HIV-1 envelope glycoprotein (CN54gp140). RSVs comprised a mucoadhesive matrix-forming and vaginal fluid absorbing polymer. The mucoadhesive and rheological properties of the RSVs were evaluated in vitro, and the distribution, antigenicity and release of CN54gp140 were analysed by ELISA. CN54gp140 was uniformly distributed within the RSVs and continuously released in vitro in an antigenically intact form over 24 h. Vaginal administration to rabbits induced specific serum IgG, and IgG and IgA in genital tract secretions. The RSVs are a viable delivery modality for vaginal immunization. PMID:19747994

  18. A Single HIV-1 Cluster and a Skewed Immune Homeostasis Drive the Early Spread of HIV among Resting CD4+ Cell Subsets within One Month Post-Infection

    PubMed Central

    Avettand-Fenoël, Véronique; Nembot, Georges; Mélard, Adeline; Blanc, Catherine; Lascoux-Combe, Caroline; Slama, Laurence; Allegre, Thierry; Allavena, Clotilde; Yazdanpanah, Yazdan; Duvivier, Claudine; Katlama, Christine; Goujard, Cécile; Seksik, Bao Chau Phung; Leplatois, Anne; Molina, Jean-Michel; Meyer, Laurence; Autran, Brigitte; Rouzioux, Christine

    2013-01-01

    Optimizing therapeutic strategies for an HIV cure requires better understanding the characteristics of early HIV-1 spread among resting CD4+ cells within the first month of primary HIV-1 infection (PHI). We studied the immune distribution, diversity, and inducibility of total HIV-DNA among the following cell subsets: monocytes, peripheral blood activated and resting CD4 T cells, long-lived (naive [TN] and central-memory [TCM]) and short-lived (transitional-memory [TTM] and effector-memory cells [TEM]) resting CD4+T cells from 12 acutely-infected individuals recruited at a median 36 days from infection. Cells were sorted for total HIV-DNA quantification, phylogenetic analysis and inducibility, all studied in relation to activation status and cell signaling. One month post-infection, a single CCR5-restricted viral cluster was massively distributed in all resting CD4+ subsets from 88% subjects, while one subject showed a slight diversity. High levels of total HIV-DNA were measured among TN (median 3.4 log copies/million cells), although 10-fold less (p = 0.0005) than in equally infected TCM (4.5), TTM (4.7) and TEM (4.6) cells. CD3−CD4+ monocytes harbored a low viral burden (median 2.3 log copies/million cells), unlike equally infected resting and activated CD4+ T cells (4.5 log copies/million cells). The skewed repartition of resting CD4 subsets influenced their contribution to the pool of resting infected CD4+T cells, two thirds of which consisted of short-lived TTM and TEM subsets, whereas long-lived TN and TCM subsets contributed the balance. Each resting CD4 subset produced HIV in vitro after stimulation with anti-CD3/anti-CD28+IL-2 with kinetics and magnitude varying according to subset differentiation, while IL-7 preferentially induced virus production from long-lived resting TN cells. In conclusion, within a month of infection, a clonal HIV-1 cluster is massively distributed among resting CD4 T-cell subsets with a flexible inducibility, suggesting that

  19. Cidofovir Activity against Poxvirus Infections

    PubMed Central

    Andrei, Graciela; Snoeck, Robert

    2010-01-01

    Cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine, HPMPC] is an acyclic nucleoside analog approved since 1996 for clinical use in the treatment of cytomegalovirus (CMV) retinitis in AIDS patients. Cidofovir (CDV) has broad-spectrum activity against DNA viruses, including herpes-, adeno-, polyoma-, papilloma- and poxviruses. Among poxviruses, cidofovir has shown in vitro activity against orthopox [vaccinia, variola (smallpox), cowpox, monkeypox, camelpox, ectromelia], molluscipox [molluscum contagiosum] and parapox [orf] viruses. The anti-poxvirus activity of cidofovir in vivo has been shown in different models of infection when the compound was administered either intraperitoneal, intranasal (aerosolized) or topically. In humans, cidofovir has been successfully used for the treatment of recalcitrant molluscum contagiosum virus and orf virus in immunocompromised patients. CDV remains a reference compound against poxviruses and holds potential for the therapy and short-term prophylaxis of not only orthopox- but also parapox- and molluscipoxvirus infections. PMID:21994641

  20. Cidofovir Activity against Poxvirus Infections.

    PubMed

    Andrei, Graciela; Snoeck, Robert

    2010-12-01

    Cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine, HPMPC] is an acyclic nucleoside analog approved since 1996 for clinical use in the treatment of cytomegalovirus (CMV) retinitis in AIDS patients. Cidofovir (CDV) has broad-spectrum activity against DNA viruses, including herpes-, adeno-, polyoma-, papilloma- and poxviruses. Among poxviruses, cidofovir has shown in vitro activity against orthopox [vaccinia, variola (smallpox), cowpox, monkeypox, camelpox, ectromelia], molluscipox [molluscum contagiosum] and parapox [orf] viruses. The anti-poxvirus activity of cidofovir in vivo has been shown in different models of infection when the compound was administered either intraperitoneal, intranasal (aerosolized) or topically. In humans, cidofovir has been successfully used for the treatment of recalcitrant molluscum contagiosum virus and orf virus in immunocompromised patients. CDV remains a reference compound against poxviruses and holds potential for the therapy and short-term prophylaxis of not only orthopox- but also parapox- and molluscipoxvirus infections.

  1. Infant HIV-1 Infection Severely Impairs the Bacille Calmette-Guerin Vaccine-Induced Immune Response1

    PubMed Central

    Mansoor, Nazma; Scriba, Thomas J.; de Kock, Marwou; Tameris, Michele; Abel, Brian; Keyser, Alana; Little, Francesca; Soares, Andreia; Gelderbloem, Sebastian; Mlenjeni, Silvia; Denation, Lea; Hawkridge, Anthony; Boom, W. Henry; Kaplan, Gilla; Hussey, Gregory D.; Hanekom, Willem A.

    2010-01-01

    Background World-wide, most infants born to HIV-infected mothers receive BCG. Tuberculosis is a major cause of death of HIV-infected infants in sub-Saharan Africa, and should be prevented. However, BCG may itself cause disease (BCGosis) in these infants. Information regarding the immunogenicity of BCG is imperative for the risk/benefit assessment of BCG vaccination in HIV-infected infants; however, no such data exists. Methods We compared BCG-induced CD4 and CD8 T cell responses, assessed by flow cytometry, in HIV-infected (n = 20), HIV-exposed but uninfected (n = 25), and HIV-unexposed (n = 23) infants, over their first year of life. Results BCG vaccination of the 2 HIV-uninfected groups induced a robust response, characterized by IFN-γ, TNF-α, and/or IL-2-expressing CD4 T cells. In contrast, HIV-infected infants had a markedly lower response, throughout the first year of life. These infants also had significantly reduced numbers of IFN-γ, TNF-α and IL-2 co-expressing polyfunctional CD4 T cells, thought to indicate T cell quality. Conclusions HIV-1 infection severely impairs the BCG-specific T cell response during the first year of life. BCG may therefore provide little, if any, vaccine-induced benefit in HIV-infected infants. Considering the significant risk of BCGosis, these data strongly support not giving BCG to HIV-infected infants. PMID:19236280

  2. Pentavalent HIV-1 vaccine protects against simian-human immunodeficiency virus challenge

    PubMed Central

    Bradley, Todd; Pollara, Justin; Santra, Sampa; Vandergrift, Nathan; Pittala, Srivamshi; Bailey-Kellogg, Chris; Shen, Xiaoying; Parks, Robert; Goodman, Derrick; Eaton, Amanda; Balachandran, Harikrishnan; Mach, Linh V.; Saunders, Kevin O.; Weiner, Joshua A.; Scearce, Richard; Sutherland, Laura L.; Phogat, Sanjay; Tartaglia, Jim; Reed, Steven G.; Hu, Shiu-Lok; Theis, James F.; Pinter, Abraham; Montefiori, David C.; Kepler, Thomas B.; Peachman, Kristina K.; Rao, Mangala; Michael, Nelson L.; Suscovich, Todd J.; Alter, Galit; Ackerman, Margaret E.; Moody, M. Anthony; Liao, Hua-Xin; Tomaras, Georgia; Ferrari, Guido; Korber, Bette T.; Haynes, Barton F.

    2017-01-01

    The RV144 Thai trial HIV-1 vaccine of recombinant poxvirus (ALVAC) and recombinant HIV-1 gp120 subtype B/subtype E (B/E) proteins demonstrated 31% vaccine efficacy. Here we design an ALVAC/Pentavalent B/E/E/E/E vaccine to increase the diversity of gp120 motifs in the immunogen to elicit a broader antibody response and enhance protection. We find that immunization of rhesus macaques with the pentavalent vaccine results in protection of 55% of pentavalent-vaccine-immunized macaques from simian–human immunodeficiency virus (SHIV) challenge. Systems serology of the antibody responses identifies plasma antibody binding to HIV-infected cells, peak ADCC antibody titres, NK cell-mediated ADCC and antibody-mediated activation of MIP-1β in NK cells as the four immunological parameters that best predict decreased infection risk that are improved by the pentavalent vaccine. Thus inclusion of additional gp120 immunogens to a pox-prime/protein boost regimen can augment antibody responses and enhance protection from a SHIV challenge in rhesus macaques. PMID:28593989

  3. A candidate HIV/AIDS vaccine (MVA-B) lacking vaccinia virus gene C6L enhances memory HIV-1-specific T-cell responses.

    PubMed

    García-Arriaza, Juan; Nájera, José Luis; Gómez, Carmen E; Tewabe, Nolawit; Sorzano, Carlos Oscar S; Calandra, Thierry; Roger, Thierry; Esteban, Mariano

    2011-01-01

    The vaccinia virus (VACV) C6 protein has sequence similarities with the poxvirus family Pox_A46, involved in regulation of host immune responses, but its role is unknown. Here, we have characterized the C6 protein and its effects in virus replication, innate immune sensing and immunogenicity in vivo. C6 is a 18.2 kDa protein, which is expressed early during virus infection and localizes to the cytoplasm of infected cells. Deletion of the C6L gene from the poxvirus vector MVA-B expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (MVA-B ΔC6L) had no effect on virus growth kinetics; therefore C6 protein is not essential for virus replication. The innate immune signals elicited by MVA-B ΔC6L in human macrophages and monocyte-derived dendritic cells (moDCs) are characterized by the up-regulation of the expression of IFN-β and IFN-α/β-inducible genes. In a DNA prime/MVA boost immunization protocol in mice, flow cytometry analysis revealed that MVA-B ΔC6L enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4+ and CD8+ T-cell memory immune responses, with most of the HIV-1 responses mediated by the CD8+ T-cell compartment with an effector phenotype. Significantly, while MVA-B induced preferentially Env- and Gag-specific CD8+ T-cell responses, MVA-B ΔC6L induced more Gag-Pol-Nef-specific CD8+ T-cell responses. Furthermore, MVA-B ΔC6L enhanced the levels of antibodies against Env in comparison with MVA-B. These findings revealed that C6 can be considered as an immunomodulator and that deleting C6L gene in MVA-B confers an immunological benefit by enhancing IFN-β-dependent responses and increasing the magnitude and quality of the T-cell memory immune responses to HIV-1 antigens. Our observations are relevant for the improvement of MVA vectors as HIV-1 vaccines.

  4. HIV-1 Receptor Binding Site-Directed Antibodies Using a VH1-2 Gene Segment Orthologue Are Activated by Env Trimer Immunization

    PubMed Central

    Bale, Shridhar; Phad, Ganesh E.; Guenaga, Javier; Wilson, Richard; Soldemo, Martina; McKee, Krisha; Sundling, Christopher; Mascola, John; Li, Yuxing; Wyatt, Richard T.; Karlsson Hedestam, Gunilla B.

    2014-01-01

    Broadly neutralizing antibodies (bNAbs) isolated from chronically HIV-1 infected individuals reveal important information regarding how antibodies target conserved determinants of the envelope glycoprotein (Env) spike such as the primary receptor CD4 binding site (CD4bs). Many CD4bs-directed bNAbs use the same heavy (H) chain variable (V) gene segment, VH1-2*02, suggesting that activation of B cells expressing this allele is linked to the generation of this type of Ab. Here, we identify the rhesus macaque VH1.23 gene segment to be the closest macaque orthologue to the human VH1-2 gene segment, with 92% homology to VH1-2*02. Of the three amino acids in the VH1-2*02 gene segment that define a motif for VRC01-like antibodies (W50, N58, flanking the HCDR2 region, and R71), the two identified macaque VH1.23 alleles described here encode two. We demonstrate that immunization with soluble Env trimers induced CD4bs-specific VH1.23-using Abs with restricted neutralization breadth. Through alanine scanning and structural studies of one such monoclonal Ab (MAb), GE356, we demonstrate that all three HCDRs are involved in neutralization. This contrasts to the highly potent CD4bs-directed VRC01 class of bNAb, which bind Env predominantly through the HCDR2. Also unlike VRC01, GE356 was minimally modified by somatic hypermutation, its light (L) chain CDRs were of average lengths and it displayed a binding footprint proximal to the trimer axis. These results illustrate that the Env trimer immunogen used here activates B cells encoding a VH1-2 gene segment orthologue, but that the resulting Abs interact distinctly differently with the HIV-1 Env spike compared to VRC01. PMID:25166308

  5. Simultaneous approach using systemic, mucosal and transcutaneous routes of immunization for development of protective HIV-1 vaccines.

    PubMed

    Belyakov, I M; Ahlers, J D

    2011-01-01

    Mucosal tissues are major sites of HIV entry and initial infection. Induction of a local mucosal cytotoxic T lymphocyte response is considered an important goal in developing an effective HIV vaccine. In addition, activation and recruitment of memory CD4(+) and CD8(+) T cells in systemic lymphoid circulation to mucosal effector sites might provide the firewall needed to prevent virus spread. Therefore a vaccine that generates CD4(+) and CD8(+) responses in both mucosal and systemic tissues might be required for protection against HIV. However, optimal routes and number of vaccinations required for the generation of long lasting CD4(+) and CD8(+) CTL effector and memory responses are not well understood especially for mucosal T cells. A number of studies looking at protective immune responses against diverse mucosal pathogens have shown that mucosal vaccination is necessary to induce a compartmentalized immune response including maximum levels of mucosal high-avidity CD8(+) CTL, antigen specific mucosal antibodies titers (especially sIgA), as well as induction of innate anti-viral factors in mucosa tissue. Immune responses are detectable at mucosal sites after systemic delivery of vaccine, and prime boost regimens can amplify the magnitude of immune responses in mucosal sites and in systemic lymphoid tissues. We believe that the most optimal mucosal and systemic HIV/SIV specific protective immune responses and innate factors might best be achieved by simultaneous mucosal and systemic prime and boost vaccinations. Similar principals of vaccination may be applied for vaccine development against cancer and highly invasive pathogens that lead to chronic infection.

  6. Immune Reconstitution During the First Year of Antiretroviral Therapy of HIV-1-Infected Adults in Rural Burkina Faso

    PubMed Central

    Tiba, Fabrice; Nauwelaers, Frans; Traoré, Siaka; Coulibaly, Boubacar; Ouedraogo, Thierry; Compaoré, Adama; Kräusslich, Hans-Georg; Böhler, Thomas

    2012-01-01

    There are no data on the outcome of highly active antiretroviral therapy (HAART) in HIV-infected adults in rural Burkina Faso. We therefore assessed CD4+ T-cell counts and HIV-1 plasma viral load (VL), the proportion of naive T-cells (co-expressing CCR7 and CD45RA) and T-cell activation (expression of CD95 or CD38) in 61 previously untreated adult patients from Nouna, Burkina Faso, at baseline and 2 weeks, 1, 3, 6, 9 and 12 months after starting therapy. Median CD4+ T-cell counts increased from 174 (10th-90th percentile: 33-314) cells/µl at baseline to 300 (114- 505) cells/µl after 3 months and 360 (169-562) cells/µl after 12 months of HAART. Median VL decreased from 5.8 (4.6- 6.6) log10 copies/ml at baseline to 1.6 (1.6-2.3) log10 copies/ml after 12 months. Early CD4+ T-cell recovery was accompanied by a reduction of the expression levels of CD95 and CD38 on T-cells. Out of 42 patients with complete virological follow-up under HAART, 19 (45%) achieved concordant good immunological (gain of ≥100 CD4+ T-cells/µl above baseline) and virological (undetectable VL) responses after 12 months of treatment (intention-to-treat analysis). Neither a decreased expression of the T-cell activation markers CD38 and CD95, nor an increase in the percentage of naive T-cells reliably predicted good virological treatment responses in patients with good CD4+ T-cell reconstitution. Repeated measurement of CD4+ T-cell counts during HAART remains the most important parameter for immunologic monitoring. Substitution of repeated VL testing by determination of T-cell activation levels (e.g., CD38 expression on CD8+ T-cells) should be applied with caution. PMID:22435082

  7. Synergistic effect of combined HIV/HCV immunogens: a combined HIV-1/HCV candidate vaccine induces a higher level of CD8+ T cell-immune responses in HLA-A2.1 mice.

    PubMed

    Azizi, Ali; Ghorbani, Masoud; Soare, Catalina; Mojibian, Majid; Diaz-Mitoma, Francisco

    2007-03-01

    Dual infections with HIV-1 and Hepatitis C virus (HCV) may proceed in concert to cause severe disease. HIV positive individuals that become infected with HCV advance more rapidly to AIDS than those that are infected with HIV-1 alone. In this study, HLA-A2.1 mice were immunized with a combination vaccine including HIV and HCV immunogens (polycistronic DNA + proteins) or vaccine containing either HIV or HCV immunogens. Mice immunized with the combined HIV/HCV regimen had similar antibody titers as the group receiving either the HIV-1 or HCV only regimen. Proliferative immune responses showed that mice receiving the combined HIV/HCV vaccine exhibited a three fold higher stimulation index (SI) to gp120 than mice immunized with the vaccine containing HIV alone. To determine whether our vaccine strategy induced Th1 or Th2 immune responses, IFN-gamma and IL-4/IL-5 were measured. The combined HIV/HCV vaccine induced a higher level of Th1 responses to HIV-1 gag protein compared with the other groups, as measured by IFN-gamma production. Interestingly, detection of IFN-gamma by ELISPOT assay demonstrated that the combined HIV/HCV vaccine group had increased numbers of spot forming cells (SFC) to HIV-gp120 peptides when compared to that of the HIV-1 only vaccine group. The combined HIV/HCV vaccine group also showed an increase in SFC to HCV-core peptides in comparison with the group receiving the HCV only vaccine. Intracellular IFN-gamma staining confirmed the ELISPOT results and demonstrated that the combined HIV/HCV group had significantly higher percentages of HIV and HCV-specific CD8+ T cells in comparison to the groups receiving the HIV or HCV vaccines. These results suggest a new approach to maximize vaccine efficacy against HIV and HCV.

  8. Cryptococcal Immune Reconstitution Inflammatory Syndrome in HIV-1–infected individuals: Literature Review and Proposed Clinical Case Definitions

    PubMed Central

    Haddow, Lewis J; Colebunders, Robert; Meintjes, Graeme; Lawn, Stephen D; Elliott, Julian H; Manabe, Yukari C; Bohjanen, Paul R; Sungkanuparph, Somnuek; Easterbrook, Philippa J; French, Martyn A; Boulware, David R

    2011-01-01

    Cryptococcal immune reconstitution inflammatory syndrome (C-IRIS) may present as a clinical deterioration or new presentation of cryptococcal disease following initiation of antiretroviral therapy (ART) and is believed to be caused by recovery of cryptococcus-specific immune responses. We have reviewed the existing literature on C-IRIS to inform the development of a consensus case definition specific for paradoxical cryptococcal IRIS in patients with known cryptococcal disease prior to ART, and a second definition for incident cases of cryptococcosis developing during ART (here termed ART-associated cryptococcosis), a proportion of which are likely to be “unmasking” C-IRIS. These structured case definitions are intended for use in future clinical, epidemiologic and immunopathologic studies of C-IRIS, harmonizing diagnostic criteria, and facilitating comparisons between studies. As with tuberculosis-associated IRIS, these proposed definitions should be regarded as preliminary until further insights into the immunopathology of IRIS permit their refinement. PMID:21029993

  9. Immunogenicity and sustainability of the immune response in Brazilian HIV-1-infected individuals vaccinated with inactivated triple influenza vaccine.

    PubMed

    Souza, Thiago Moreno L; Santini-Oliveira, Marilia; Martorelli, Andressa; Luz, Paula M; Vasconcellos, Mauricio T L; Giacoia-Gripp, Carmem B W; Morgado, Mariza; Nunes, Estevão P; Lemos, Alberto S; Ferreira, Ana C G; Moreira, Ronaldo I; Veloso, Valdiléa G; Siqueira, Marilda; Grinsztejn, Beatriz; Camacho, Luiz A B

    2016-03-01

    HIV-infected individuals have a higher risk of serious illnesses following infection by infection with influenza. Although anti-influenza vaccination is recommended, immunosuppression may limit their response to active immunization. We followed-up a cohort of HIV-infected individuals vaccinated against influenza to assess the immunogenicity and sustainability of the immune response to vaccination. Individuals were vaccinated 2011 with inactivated triple influenza vaccine (TIV), and they had received in 2010 the monovalent anti-A(H1N1)pdm09 vaccine. The sustainability of the immune response to A(H1N1)pdm09 at 12 months after monovalent vaccination fell, both in individuals given two single or two double doses. For these individuals, A(H1N1)pdm09 component from TIV acted as a booster, raising around 40% the number of seroprotected individuals. Almost 70% of the HIV-infected individuals were already seroprotected to A/H3N2 at baseline. Again, TIV boosted over 90% the seroprotection to A/H3N2. Anti-A/H3N2 titers dropped by 20% at 6 months after vaccination. Pre-vaccination seroprotection rate to influenza B (victoria lineage) was the lowest among those tested, seroconversion rates were higher after vaccination. Seroconversion/protection after TIV vaccination did not differ significantly across categories of clinical and demographic variables. Anti-influenza responses in Brazilian HIV-infected individuals reflected both the previous history of virus circulation in Brazil and vaccination.

  10. Synthetic long peptide booster immunization in rhesus macaques primed with replication-competent NYVAC-C-KC induces a balanced CD4/CD8 T-cell and antibody response against the conserved regions of HIV-1.

    PubMed

    Mooij, Petra; Koopman, Gerrit; Drijfhout, Jan Wouter; Nieuwenhuis, Ivonne G; Beenhakker, Niels; Koestler, Josef; Bogers, Willy M J M; Wagner, Ralf; Esteban, Mariano; Pantaleo, Giuseppe; Heeney, Jonathan L; Jacobs, Bertram L; Melief, Cornelis J M

    2015-06-01

    The Thai trial (RV144) indicates that a prime-boost vaccine combination that induces both T-cell and antibody responses may be desirable for an effective HIV vaccine. We have previously shown that immunization with synthetic long peptides (SLP), covering the conserved parts of SIV, induced strong CD4 T-cell and antibody responses, but only modest CD8 T-cell responses. To generate a more balanced CD4/CD8 T-cell and antibody response, this study evaluated a pox-vector prime/SLP boost strategy in rhesus macaques. Priming with a replication-competent NYVAC, encoding HIV-1 clade C gag, pol and nef, induced modest IFNγ T-cell immune responses, predominantly directed against HIV-1 Gag. Booster immunization with SLP, covering the conserved parts of HIV-1 Gag, Pol and Env, resulted in a more than 10-fold increase in IFNγ ELISpot responses in four of six animals, which were predominantly HIV-1 Pol-specific. The animals showed a balanced polyfunctional CD4 and CD8 T-cell response and high Ab titres. © 2015 The Authors.

  11. Quasispecies tropism and compartmentalization in gut and peripheral blood during early and chronic phases of HIV-1 infection: possible correlation with immune activation markers.

    PubMed

    Rozera, G; Abbate, I; Vlassi, C; Giombini, E; Lionetti, R; Selleri, M; Zaccaro, P; Bartolini, B; Corpolongo, A; D'Offizi, G; Baiocchini, A; Del Nonno, F; Ippolito, G; Capobianchi, M R

    2014-03-01

    HIV quasispecies was analysed in plasma and proviral genomes hosted by duodenal mucosa and peripheral blood cells (PBMC) from patients with early or chronic infection, with respect to viral heterogeneity, tropism compartmentalization and extent of immune activation. Seventeen HIV-1-infected combined antiretroviral therapy naive patients were enrolled (11 early infection and six chronic infection). V3 and nef genomic regions were analysed by ultra-deep pyrosequencing. Sequences were used to infer co-receptor usage and to construct phylogenetic trees. As markers of immune activation, plasma sCD14 and soluble tumour necrosis factor receptor II (sTNFRII) levels were measured. Median diversity of HIV RNA was lower in patients with early infection versus chronic infection patients. Overall, direct correlation was observed between V3 diversity and X4 frequency; V3 diversity of HIV RNA was inversely correlated with CD4 T-cell count; median sCD14 and sTNFRII values were similar in early and chronic patients, but X4 frequency of HIV RNA was directly correlated with plasma sCD14. The proportion of patients harbouring X4 variants and median intra-patient X4 frequency of proviral genomes tended to be higher in chronic infection than early infection patients. More pronounced compartmentalization of proviral quasispecies in gut compared with PBMC samples was observed in patients with early infection compared with chronic patients. The loss of gut/PBMC compartmentalization in more advanced stages of HIV infection was confirmed by longitudinal observation. More studies are needed to understand the pathogenetic significance of early HIV quasispecies compartmentalization and progressive intermixing of viral variants in subsequent phases of the infection, as well as the role of immune activation in tropism switch.

  12. Role of lipid structure in the humoral immune response in mice to covalent lipid-peptides from the membrane proximal region of HIV-1 gp41

    PubMed Central

    Watson, Douglas S.; Szoka, Francis C.

    2009-01-01

    The membrane proximal region (MPR) of HIV-1 gp41 is a desirable target for development of a vaccine that elicits neutralizing antibodies since the patient-derived monoclonal antibodies, 2F5 and 4E10, bind to the MPR and neutralize primary HIV isolates. The 2F5 and 4E10 antibodies cross-react with lipids and structural studies suggest that MPR immunogens may be presented in a membrane environment. We hypothesized that covalent attachment of lipid anchors would enhance the humoral immune response to MPR-derived peptides presented in liposomal bilayers. In a comparison of eight lipids conjugated to an extended 2F5 epitope peptide, a sterol, cholesterol hemisuccinate (CHEMS), was found to promote the strongest anti-peptide IgG titers (6.4 × 104) in sera of BALB/C mice. Two lipid anchors, palmitic acid and phosphatidylcholine, failed to elicit a detectable serum anti-peptide IgG response. Association with the liposomal vehicle contributed to the ability of a lipopeptide to elicit anti-peptide antibodies, but no other single factor, such as position of the lipid anchor, peptide helical content, lipopeptide partition coefficient, or presence of phosphate on the anchor clearly determined lipopeptide potency. Conjugation to CHEMS also rendered a 4E10 epitope peptide immunogenic (5.6 × 102 IgG titer in serum). Finally, attachment of CHEMS to a peptide spanning both the 2F5 and 4E10 epitopes elicited serum IgG antibodies that bound to each of the individual epitopes as well as to recombinant gp140. Further research into the mechanism of how structure influences the immune response to the MPR may lead to immunogens that could be useful in prime-boost regimens for focusing the immune response in an HIV vaccine. PMID:19520200

  13. Coupling of HIV-1 Antigen to the Selective Autophagy Receptor SQSTM1/p62 Promotes T-Cell-Mediated Immunity

    PubMed Central

    Andersen, Aram Nikolai; Landsverk, Ole Jørgen; Simonsen, Anne; Bogen, Bjarne; Corthay, Alexandre; Øynebråten, Inger

    2016-01-01

    Vaccines aiming to promote T-cell-mediated immune responses have so far showed limited efficacy, and there is a need for novel strategies. Studies indicate that autophagy plays an inherent role in antigen processing and presentation for CD4+ and CD8+ T cells. Here, we report a novel vaccine strategy based on fusion of antigen to the selective autophagy receptor sequestosome 1 (SQSTM1)/p62. We hypothesized that redirection of vaccine antigen from proteasomal degradation into the autophagy pathway would increase the generation of antigen-specific T cells. A hybrid vaccine construct was designed in which the antigen is fused to the C-terminus of p62, a signaling hub, and a receptor that naturally delivers ubiquitinated cargo for autophagic degradation. Fusion of the human immunodeficiency virus-1 antigen Gagp24 to p62 resulted in efficient antigen delivery into the autophagy pathway. Intradermal immunization of mice revealed that, in comparison to Gagp24 delivered alone, fusion to p62 enhanced the number of Gagp24-specific interferon-γ-producing T cells, including CD8+ T cells. The strategy may also have the potential to modulate the antigenic peptide repertoire. Because p62 and autophagy are highly conserved between species, we anticipate this strategy to be a candidate for the development of T-cell-based vaccines in humans. PMID:27242780

  14. Antibody repertoire against HIV-1 gp120 triggered in nude and normal mice by GM-CSF/gp120 immunization.

    PubMed

    del Real, G; Llorente, M; Lucas, P; Kremer, L; Torán, J L; Martínez-A, C

    1999-08-01

    Granulocyte-macrophage colony stimulating factor (GM-CSF) facilitates the induction of primary immune responses by activating and recruiting antigen-presenting cells (APC), which efficiently present antigen determinants to Th cells. We have derived a functional GM-CSF/gp120 chimeric protein that, following immunization in soluble, adjuvant-independent form in normal mice, triggers highly specific, high affinity anti-gp120 antibodies. In contrast, nude mice respond with mutated, polyreactive, low affinity antibodies that mature further and increase in affinity in T cell-reconstituted nude mice. Anti-gp120 antibody production in nude mice is mediated principally by GM-CSF/gp120-triggered IL-4 production, since neutralizing anti-IL-4 abrogates the in vivo response. The anti-gp120 antibody response in normal, nude and T cell-reconstituted nude mice is encoded at a remarkably high frequency by the VH81X and VH7183 genes, a family used notably during fetal life and, when expressed at the adult stage, associated with autoimmune disease. We conclude that HIV gp120 binds and selects a subpopulation of developing B cells expressing a set of VH genes associated with immunodeficiency and autoimmunity.

  15. Low-Replicating Viruses and Strong Anti-Viral Immune Response Associated with Prolonged Disease Control in a Superinfected HIV-1 LTNP Elite Controller

    PubMed Central

    Pernas, María; Casado, Concepción; Arcones, Carolina; Llano, Anuska; Sánchez-Merino, Víctor; Mothe, Beatriz; Vicario, José L.; Grau, Eulalia; Ruiz, Lidia; Sánchez, Jorge; Telenti, Amalio; Yuste, Eloísa; Brander, Christian; Galíndez, Cecilio López-

    2012-01-01

    Objective To study the causes for the lack of clinical progression in a superinfected HIV-1 LTNP elite controller patient. Methodology and Principal Findings We studied host genetic, virological and immunological factors associated with viral control in a SI long term non progressor elite controller (LTNP-EC). The individual contained both viruses and maintained undetectable viral loads for >20 years and he did not express any of the described host genetic polymorphisms associated with viral control. None of four full-length gp160 recombinants derived from the LTNP-EC replicated in heterologous peripheral blood mononuclear cells. CTL responses after SI were maintained in two samples separated by 9 years and they were higher in breadth and magnitude than responses seen in most of 250 treatment naïve patients and also 25 controller subjects. The LTNP-EC showed a neutralization response, against 4 of the 6 viruses analyzed, superior to other ECs. Conclusions The study demonstrated that a strong and sustained cellular and humoral immune response and low replicating viruses are associated with viral control in the superinfected LTNP-EC. PMID:22384103

  16. Synthetic consensus HIV-1 DNA induces potent cellular immune responses and synthesis of granzyme B, perforin in HIV infected individuals.

    PubMed

    Morrow, Matthew P; Tebas, Pablo; Yan, Jian; Ramirez, Lorenzo; Slager, Anna; Kraynyak, Kim; Diehl, Malissa; Shah, Divya; Khan, Amir; Lee, Jessica; Boyer, Jean; Kim, J Joseph; Sardesai, Niranjan Y; Weiner, David B; Bagarazzi, Mark L

    2015-03-01

    This study evaluated the safety and immunogenicity of PENNVAX-B in 12 HIV infected individuals. PENNVAX-B is a combination of three optimized synthetic plasmids encoding for multiclade HIV Gag and Pol and a consensus CladeB Env delivered by electroporation. HIV infected individuals whose virus was effectively suppressed using highly active antiretroviral therapy (HAART) received PENNVAX-B DNA followed by electroporation with CELLECTRA-5P at study weeks 0, 4, 8, and 16. Local administration site and systemic reactions to PENNVAX-B were recorded after each treatment along with any adverse events. Pain of the treatment procedure was assessed using a Visual Analog Scale. Whole PBMCs were isolated for use in IFN ELISpot and Flow Cytometric assays. PENNVAX-B was generally safe and well tolerated. Overall, the four dose regimen was not associated with any serious adverse events or severe local or systemic reactions. A rise in antigen-specific SFU was detected in the INFγ ELISpot assay in all 12 participants. T cells from 8/12 participants loaded with both granzyme B and perforin in response to HIV antigen, an immune finding characteristic of long-term nonprogressors (LTNPs) and elite controllers (ECs). Thus administration of PENNVAX-B may prove useful adjunctive therapy to ART for treatment and control of HIV infection.

  17. Synthetic Consensus HIV-1 DNA Induces Potent Cellular Immune Responses and Synthesis of Granzyme B, Perforin in HIV Infected Individuals

    PubMed Central

    Morrow, Matthew P; Tebas, Pablo; Yan, Jian; Ramirez, Lorenzo; Slager, Anna; Kraynyak, Kim; Diehl, Malissa; Shah, Divya; Khan, Amir; Lee, Jessica; Boyer, Jean; Kim, J Joseph; Sardesai, Niranjan Y; Weiner, David B; Bagarazzi, Mark L

    2015-01-01

    This study evaluated the safety and immunogenicity of PENNVAX-B in 12 HIV infected individuals. PENNVAX-B is a combination of three optimized synthetic plasmids encoding for multiclade HIV Gag and Pol and a consensus CladeB Env delivered by electroporation. HIV infected individuals whose virus was effectively suppressed using highly active antiretroviral therapy (HAART) received PENNVAX-B DNA followed by electroporation with CELLECTRA-5P at study weeks 0, 4, 8, and 16. Local administration site and systemic reactions to PENNVAX-B were recorded after each treatment along with any adverse events. Pain of the treatment procedure was assessed using a Visual Analog Scale. Whole PBMCs were isolated for use in IFN ELISpot and Flow Cytometric assays. PENNVAX-B was generally safe and well tolerated. Overall, the four dose regimen was not associated with any serious adverse events or severe local or systemic reactions. A rise in antigen-specific SFU was detected in the INFγ ELISpot assay in all 12 participants. T cells from 8/12 participants loaded with both granzyme B and perforin in response to HIV antigen, an immune finding characteristic of long-term nonprogressors (LTNPs) and elite controllers (ECs). Thus administration of PENNVAX-B may prove useful adjunctive therapy to ART for treatment and control of HIV infection. PMID:25531694

  18. Immune and Viral Correlates of “Secondary Viral Control” after Treatment Interruption in Chronically HIV-1 Infected Patients

    PubMed Central

    Van Gulck, Ellen; Bracke, Lotte; Heyndrickx, Leo; Coppens, Sandra; Atkinson, Derek; Merlin, Céline; Pasternak, Alexander; Florence, Eric; Vanham, Guido

    2012-01-01

    Upon interruption of antiretroviral therapy, HIV-infected patients usually show viral load rebound to pre-treatment levels. Four patients, hereafter referred to as secondary controllers (SC), were identified who initiated therapy during chronic infection and, after stopping treatment, could control virus replication at undetectable levels for more than six months. In the present study we set out to unravel possible viral and immune parameters or mechanisms of this phenomenon by comparing secondary controllers with elite controllers and non-controllers, including patients under HAART. As candidate correlates of protection, virus growth kinetics, levels of intracellular viral markers, several aspects of HIV-specific CD4+ and CD8+ T cell function and HIV neutralizing antibodies were investigated. As expected all intracellular viral markers were lower in aviremic as compared to viremic subjects, but in addition both elite and secondary controllers had lower levels of viral unspliced RNA in PBMC as compared to patients on HAART. Ex vivo cultivation of the virus from CD4+ T cells of SC consistently failed in one patient and showed delayed kinetics in the three others. Formal in vitro replication studies of these three viruses showed low to absent growth in two cases and a virus with normal fitness in the third case. T cell responses toward HIV peptides, evaluated in IFN-γ ELISPOT, revealed no significant differences in breadth, magnitude or avidity between SC and all other patient groups. Neither was there a difference in polyfunctionality of CD4+ or CD8+ T cells, as evaluated with intracellular cytokine staining. However, secondary and elite controllers showed higher proliferative responses to Gag and Pol peptides. SC also showed the highest level of autologous neutralizing antibodies. These data suggest that higher T cell proliferative responses and lower replication kinetics might be instrumental in secondary viral control in the absence of treatment. PMID:22666392

  19. Changes in Vaginal Microbiota and Immune Mediators in HIV-1-Seronegative Kenyan Women Initiating Depot Medroxyprogesterone Acetate.

    PubMed

    Roxby, Alison C; Fredricks, David N; Odem-Davis, Katherine; Ásbjörnsdóttir, Kristjana; Masese, Linnet; Fiedler, Tina L; De Rosa, Stephen; Jaoko, Walter; Kiarie, James N; Overbaugh, Julie; McClelland, R Scott

    2016-04-01

    Depot medroxyprogesterone acetate (DMPA) is associated with HIV acquisition. We studied changes in vaginal microbiota and inflammatory milieu after DMPA initiation. In a cohort of HIV-negative Kenyan women, we collected monthly vaginal swabs over 1 year before and after DMPA. Using quantitative polymerase chain reaction, we compared quantities of Lactobacillus crispatus, Lactobacillus jensenii, Lactobacillus iners, Gardnerella vaginalis, and total bacterial load (16S ribosomal RNA gene levels). Six vaginal immune mediators were measured with enzyme-linked immunosorbent assay. Trends in the detection and quantity of bacteria were estimated by logistic and linear mixed-effects regression. From 2010 to 2012, 15 HIV-seronegative women initiated DMPA, contributing 85 visits (median, 6 visits/woman; range, 3-8 visits/woman). The median time of DMPA-exposed follow-up was 8.4 months (range, 1.5-11.6 months). Seven women (46%) had bacterial vaginosis within 70 days before DMPA start. L. iners was detected in 13 women (87%) before DMPA start, but other lactobacilli were rarely detected. Gardnerella vaginalis decreased by 0.21 log10 copies per swab per month after DMPA exposure (P = 0.01). Total bacterial load decreased by 0.08 log10 copies per swab per month of DMPA (P = 0.02). Sustained decreases in interleukin (IL)-6 (P = 0.03), IL-8 (P = 0.04), and IL-1 receptor antagonist (P < 0.001) were also noted. Nine women (60%) had L. crispatus detected post-DMPA, which significantly correlated with reduced IL-6 (P < 0.01) and IL-8 (P = 0.02). Initiation of DMPA led to sustained shifts in vaginal bacterial concentrations and levels of inflammatory mediators. Further studies are warranted to outline components of the vaginal microbiota influenced by DMPA use and impact on HIV susceptibility.

  20. The Evolution of Poxvirus Vaccines

    PubMed Central

    Sánchez-Sampedro, Lucas; Perdiguero, Beatriz; Mejías-Pérez, Ernesto; García-Arriaza, Juan; Di Pilato, Mauro; Esteban, Mariano

    2015-01-01

    After Edward Jenner established human vaccination over 200 years ago, attenuated poxviruses became key players to contain the deadliest virus of its own family: Variola virus (VARV), the causative agent of smallpox. Cowpox virus (CPXV) and horsepox virus (HSPV) were extensively used to this end, passaged in cattle and humans until the appearance of vaccinia virus (VACV), which was used in the final campaigns aimed to eradicate the disease, an endeavor that was accomplished by the World Health Organization (WHO) in 1980. Ever since, naturally evolved strains used for vaccination were introduced into research laboratories where VACV and other poxviruses with improved safety profiles were generated. Recombinant DNA technology along with the DNA genome features of this virus family allowed the generation of vaccines against heterologous diseases, and the specific insertion and deletion of poxvirus genes generated an even broader spectrum of modified viruses with new properties that increase their immunogenicity and safety profile as vaccine vectors. In this review, we highlight the evolution of poxvirus vaccines, from first generation to the current status, pointing out how different vaccines have emerged and approaches that are being followed up in the development of more rational vaccines against a wide range of diseases. PMID:25853483

  1. The evolution of poxvirus vaccines.

    PubMed

    Sánchez-Sampedro, Lucas; Perdiguero, Beatriz; Mejías-Pérez, Ernesto; García-Arriaza, Juan; Di Pilato, Mauro; Esteban, Mariano

    2015-04-07

    After Edward Jenner established human vaccination over 200 years ago, attenuated poxviruses became key players to contain the deadliest virus of its own family: Variola virus (VARV), the causative agent of smallpox. Cowpox virus (CPXV) and horsepox virus (HSPV) were extensively used to this end, passaged in cattle and humans until the appearance of vaccinia virus (VACV), which was used in the final campaigns aimed to eradicate the disease, an endeavor that was accomplished by the World Health Organization (WHO) in 1980. Ever since, naturally evolved strains used for vaccination were introduced into research laboratories where VACV and other poxviruses with improved safety profiles were generated. Recombinant DNA technology along with the DNA genome features of this virus family allowed the generation of vaccines against heterologous diseases, and the specific insertion and deletion of poxvirus genes generated an even broader spectrum of modified viruses with new properties that increase their immunogenicity and safety profile as vaccine vectors. In this review, we highlight the evolution of poxvirus vaccines, from first generation to the current status, pointing out how different vaccines have emerged and approaches that are being followed up in the development of more rational vaccines against a wide range of diseases.

  2. HIV-1 Prevention for HIV-1 Serodiscordant Couples

    PubMed Central

    Curran, Kathryn; Baeten, Jared M.; Coates, Thomas J.; Kurth, Ann; Mugo, Nelly R.

    2013-01-01

    A substantial proportion of HIV-1-infected individuals in sub-Saharan Africa are in stable relationships with HIV-1-uninfected partners, and HIV-1 serodiscordant couples thus represent an important target population for HIV-1 prevention. Couple-based HIV-1 testing and counseling facilitates identification of HIV-1 serodiscordant couples, counseling about risk reduction, and referrals to HIV-1 treatment, reproductive health services, and support services. Maximizing HIV-1 prevention for HIV-1 serodiscordant couples requires a combination of strategies, including counseling about condoms, sexual risk, fertility, contraception, and the clinical and prevention benefits of antiretroviral therapy (ART) for the HIV-1-infected partner; provision of clinical care and ART for the HIV-1-infected partner; antenatal care and services to prevent mother to child transmission for HIV-1- infected pregnant women; male circumcision for HIV-1-uninfected men; and, pending guidelines and demonstration projects, oral pre-exposure prophylaxis (PrEP) for HIV-1-uninfected partners. PMID:22415473

  3. Breast milk transmission of HIV-1.

    PubMed

    Nduati, R; John, G

    1995-12-01

    Breast milk provides infants and children immunologic, nutritional, and child spacing benefits. Yet it also transmits some viruses, for example, HIV-1. The World Health Organization recommends that, in conditions with poor access to breast milk substitutes, HIV-positive women should still breast feed due to the nutritional and infectious risk of artificial feeding. It appears that breast fed infants experience a slower progression of AIDS and death. Vertical transmission of HIV-1 may occur during pregnancy, at delivery, or through breast milk. The HIV-1 transmission rate via breast milk from acutely infected women is estimated to be 29-36%. A meta-analysis of case reports and small case series of women with chronic HIV-1 infection indicated a breast feeding transmission rate of 14%. Studies suggest that the likelihood of HIV-1 transmission via breast milk increases as duration of breast feeding increases. Infants with detectable HIV-1 DNA tend to have mothers whose absolute CD4 counts are less than 400 and have severe vitamin A deficiency. Breast milk has HIV-1 specific immunoglobulins (IgG, IgA, and IgM). It appears that HIV-1 elicits a local immune response. Breast milk of HIV-1 positive mothers with non-infected children tends to still have IgM and IgA until 18 months. Potential risk factors for breast milk transmission of HIV-1 include cracked nipples and mastitis in the mother; oral thrush, malnutrition, inflammation of the lips, and mucosal compromise in the infant; and vigorous suction of the neonate and use of the wrong equipment for suctioning. Inhibiting factors of HIV-1 in breast milk are bovine and human lactoferrin and a membrane associated protein that attaches to the CD4 receptor and thus prevents attachment of the HIV antigen gp120 to the CD4 receptor on T-cells.

  4. Combined HIV-1 Envelope Systemic and Mucosal Immunization of Lactating Rhesus Monkeys Induces a Robust Immunoglobulin A Isotype B Cell Response in Breast Milk

    PubMed Central

    Nelson, Cody S.; Pollara, Justin; Kunz, Erika L.; Jeffries, Thomas L.; Duffy, Ryan; Beck, Charles; Stamper, Lisa; Wang, Minyue; Shen, Xiaoying; Pickup, David J.; Hudgens, Michael G.; Kepler, Thomas B.; Montefiori, David C.; Moody, M. Anthony; Tomaras, Georgia D.; Liao, Hua-Xin; Haynes, Barton F.; Ferrari, Guido; Fouda, Genevieve G. A.

    2016-01-01

    ABSTRACT Maternal vaccination to induce anti-HIV immune factors in breast milk is a potential intervention to prevent postnatal HIV-1 mother-to-child transmission (MTCT). We previously demonstrated that immunization of lactating rhesus monkeys with a modified vaccinia Ankara (MVA) prime/intramuscular (i.m.) protein boost regimen induced functional IgG responses in milk, while MVA prime/intranasal (i.n.) boost induced robust milk Env-specific IgA responses. Yet, recent studies have suggested that prevention of postnatal MTCT may require both Env-specific IgA and functional IgG responses in milk. Thus, to investigate whether both responses could be elicited by a combined systemic/mucosal immunization strategy, animals previously immunized with the MVA prime/i.n. boost regimen received an i.n./i.m. combined C.1086 gp120 boost. Remarkably, high-magnitude Env-specific IgA responses were observed in milk, surpassing those in plasma. Furthermore, 29% of vaccine-elicited Env-specific B cells isolated from breast milk were IgA isotype, in stark contrast to the overwhelming predominance of IgG isotype Env-specific B cells in breast milk of chronically HIV-infected women. A clonal relationship was identified between Env-specific blood and breast milk B cells, suggesting trafficking of that cell population between the two compartments. Furthermore, IgA and IgG monoclonal antibodies isolated from Env-specific breast milk B cells demonstrated diverse Env epitope specificities and multiple effector functions, including tier 1 neutralization, antibody-dependent cellular cytotoxicity (ADCC), infected cell binding, and inhibition of viral attachment to epithelial cells. Thus, maternal i.n./i.m. combined immunization is a novel strategy to enhance protective Env-specific IgA in milk, which is subsequently transferred to the infant via breastfeeding. IMPORTANCE Efforts to increase the availability of antiretroviral therapy to pregnant and breastfeeding women in resource-limited areas

  5. Comparative impact of antiretroviral drugs on markers of inflammation and immune activation during the first two years of effective therapy for HIV-1 infection: an observational study

    PubMed Central

    2014-01-01

    Background Few studies have compared the impact of different antiretroviral regimens on residual immune activation and inflammation with discordant results. Aim of the study was to investigate the impact of various antiretroviral regimens on markers of immune activation and inflammation during the first two years of effective therapy. Methods We studied HIV-infected antiretroviral-naïve patients who began cART with either abacavir/lamivudine or tenofovir/emtricitabine, combined with ritonavir-boosted lopinavir (LPV/r), atazanavir (ATV/r) or efavirenz (EFV). All the patients had a virological response within 6 months, which was maintained for 2 years with no change in their ART regimen. C-reactive protein (hs-CRP), interleukin-6 (IL-6), soluble CD14 (sCD14), monokine induced by interferon-γ (MIG) and interferon-γ-inducible protein-10 (IP-10) were measured in stored plasma obtained at cART initiation and 24 months later. Mean changes from baseline were analyzed on loge-transformed values and multivariable linear regression models were used to study the effect of the treatment components, after adjusting for factors that might have influenced the choice of ART regimen or biomarker levels. Differences were expressed as the mean fold change percentage difference (Δ). Results Seventy-eight patients (91% males) with a median age of 43 years met the inclusion criteria. Their median baseline CD4 cell count was 315/mm3 and HIV-1 RNA level 4.6 log10 copies/ml. During the 2-years study period, IL-6, IP-10 and MIG levels fell significantly, while hs-CRP and sCD14 levels remained stable. IP-10 and MIG levels declined significantly less strongly with ATV/r than with EFV (IP-10Δ -57%, p = 0.011; MIGΔ -136%, p = 0.007), while no difference was noted between LPV/r and EFV. The decline in IL-6 did not differ significantly across the different treatment components. Conclusions After the first 2 years of successful cART, IL-6, IP-10 and MIG fell markedly while hs

  6. Adenoviral gene delivery for HIV-1 vaccination.

    PubMed

    Vanniasinkam, T; Ertl, H C J

    2005-04-01

    The AIDS epidemic continues to spread throughout nations of Africa and Asia and is by now threatening to undermine the already frail infrastructure of developing countries in Sub-Saharan Africa that are hit the hardest. The only option to stem this epidemic is through inexpensive and efficacious vaccines that prevent or at least blunt HIV-1 infections. Despite decades of pre-clinical and clinical research such vaccines remain elusive. Most anti-viral vaccines act by inducing protective levels of virus-neutralizing antibodies. The envelope protein of HIV-1, the sole target of neutralizing antibodies, is constantly changing due to mutations, B cell epitopes are masked by heavy glycosylation and the protein's structural unfolding upon binding to its CD4 receptor and chemokine co-receptors. Efforts to induce broadly cross-reactive virus-neutralizing antibodies able to induce sterilizing or near sterilizing immunity to HIV-1 have thus failed. Studies have indicated that cell-mediated immune responses and in particular CD8+ T cell responses to internal viral proteins may control HIV-1 infections without necessarily preventing them. Adenoviral vectors expressing antigens of HIV-1 are eminently suited to stimulate potent CD8+ T cell responses against transgene products, such as antigens of HIV-1. They performed well in pre-clinical studies in rodents and nonhuman primates and are currently in human clinical trials. This review summarizes the published literature on adenoviral vectors as vaccine carriers for HIV-1 and discusses advantages and disadvantages of this vaccine modality.

  7. Evaluation of VZV-specific cell-mediated immunity in adults infected with HIV-1 by using a simple IFN-γ release assay.

    PubMed

    Watanabe, Dai; Otani, Naruhito; Suzuki, Sachiko; Dohi, Hiromi; Hirota, Kazuyuki; Yonemoto, Hitoshi; Koizumi, Yusuke; Otera, Hiroshi; Yajima, Keishiro; Nishida, Yasuharu; Uehira, Tomoko; Shima, Masayuki; Shirasaka, Takuma; Okuno, Toshiomi

    2013-08-01

    The development of herpes zoster is associated with reduced varicella zoster virus (VZV)-specific cell-mediated immune (CMI) reactions. In this study, VZV-specific CMI reactions in 42 anti-VZV-IgG antibody-positive adults infected with HIV-1 were evaluated by measuring the IFN-γ production levels in whole blood in response to stimulation with ultraviolet light-inactivated live attenuated VZV vaccine. The median VZV-specific IFN-γ production level in all patients was 63 pg/ml. Antiretroviral therapy (ART)-naïve patients with an AIDS-defining illness (HIV classification category C) had significantly lower IFN-γ production than ART-naïve patients in categories A and B and patients receiving ART (P=0.0194 and P=0.0046, respectively). IFN-γ production increased significantly in patients within 1 month of the onset of recurrent VZV disease and at more than 1 year from onset, compared with patients who had never had recurrent VZV disease (P=0.0396 and P=0.0484, respectively). In multivariate analyses, category C and history of recurrent VZV disease were significant factors affecting IFN-γ production. Levels of IFN-γ were measured before and after ART in seven ART-naïve patients with no history of recurrent VZV disease, and no significant changes were observed. The results indicate that VZV-specific CMI reactions were reduced in patients with an AIDS-defining illness and enhanced in patients with a history of recurrent VZV disease, but not enhanced by ART alone. Vaccination may be necessary to inhibit the development of herpes zoster in patients receiving ART; this IFN-γ releasing assay is one useful method for evaluating VZV-specific CMI reactions in clinical settings. Copyright © 2013 Wiley Periodicals, Inc.

  8. Immune deficiency could be an early risk factor for altered insulin sensitivity in antiretroviral-naive HIV-1-infected patients: the ANRS COPANA cohort

    PubMed Central

    Boufassa, Faroudy; Goujard, Cécile; Viard, Jean-Paul; Carlier, Robert; Lefebvre, Bénédicte; Yeni, Patrick; Bouchaud, Olivier; Capeau, Jacqueline; Meyer, Laurence; Vigouroux, Corinne

    2012-01-01

    Background The relationships between immunovirological status, inflammatory markers, insulin resistance and fat distribution have not been studied in recently diagnosed (<1 year) antiretroviral-naïve HIV-1-infected patients. Methods We studied 214 antiretroviral-naïve patients at enrolment in the metabolic sub-study of the ANRS COPANA cohort. We measured clinical, immunovirological and inflammatory parameters, glucose/insulin during oral glucose tolerance test (OGTT), adipokines, subcutaneous and visceral fat surfaces (SAT and VAT, assessed by computed tomography) and the body fat distribution based on dual-energy X-ray absorptiometry (DEXA). Results Median age was 36 years; 28% of the patients were female and 35% of sub-Saharan origin; 20% had low CD4 counts (≤200/mm3). Patients with low CD4 counts were older and more frequently of sub-Saharan Africa origin, had lower BMI but not different SAT/VAT ratio and fat distribution than other patients. They also had lower total, LDL- and HDL-cholesterolemia, higher triglyceridemia and post-OGTT glycemia, higher markers of insulin resistance (insulin during OGTT and HOMA-IR) and of inflammation (hsCRP, IL-6, TNFα, sTNFR1 and sTNFR2). After adjustment for age, sex, geographic origin, BMI and waist circumference, increased insulin resistance was not related to any inflammatory marker. In multivariate analysis, low CD4 count was an independent risk factor for altered insulin sensitivity (β-coefficient for HOMA-IR: +0.90; p=0.001; CD4>500/mm3 as the reference), in addition to older age (β: +0.26 for a 10-year increase; p=0.01) and higher BMI (β: +0.07 for a 1-kg/m2 increase; p=0.003). Conclusions In ART-naive patients, severe immune deficiency but not inflammation could be an early risk factor for altered insulin sensitivity. PMID:22267473

  9. A global approach to HIV-1 vaccine development

    PubMed Central

    Stephenson, Kathryn E; Barouch, Dan H

    2013-01-01

    Summary A global human immunodeficiency virus-1 (HIV-1) vaccine will have to elicit immune responses capable of providing protection against a tremendous diversity of HIV-1 variants. In this review, we first describe the current state of the HIV-1 vaccine field, outlining the immune responses that are desired in a global HIV-1 vaccine. In particular, we emphasize the likely importance of Env-specific neutralizing and non-neutralizing antibodies for protection against HIV-1 acquisition and the likely importance of effector Gag-specific T lymphocytes for virologic control. We then highlight four strategies for developing a global HIV-1 vaccine. The first approach is to design specific vaccines for each geographic region that include antigens tailor-made to match local circulating HIV-1 strains. The second approach is to design a vaccine that will elicit Env-specific antibodies capable of broadly neutralizing all HIV-1 subtypes. The third approach is to design a vaccine that will elicit cellular immune responses that are focused on highly conserved HIV-1 sequences. The fourth approach is to design a vaccine to elicit highly diverse HIV-1-specific responses. Finally, we emphasize the importance of conducting clinical efficacy trials as the only way to determine which strategies will provide optimal protection against HIV-1 in humans. PMID:23772627

  10. Sex differences in HIV-1-mediated immunopathology.

    PubMed

    Ziegler, Susanne; Altfeld, Marcus

    2016-03-01

    The article reviews our current knowledge regarding the role of sex and sex hormones in regulating innate immune responses to viral infections, which may account for the described sex differences in immunity to HIV-1. Prominent sex differences exist in various infectious and autoimmune diseases. Biological mechanisms underlying these differences include the modulation of immunological pathways by sex hormones and gene dosage effects of immunomodulatory genes encoded by the X chromosome. During HIV-1 infections, women have been shown to present with lower viral load levels in primary infection, although their progression to AIDS is faster in comparison with men when accounting for viral load levels in chronic infection. HIV-1-infected women furthermore tend to have higher levels of immune activation and interferon-stimulated gene expression in comparison with men for the same viral load, which has been associated to innate sensing of HIV-1 by Toll-like receptor 7 and the consequent interferon-α production by plasmacytoid dendritic cells. Improvement in understanding the mechanisms associated with sex differences in HIV-1-mediated immunopathology will be critical to take sex differences into consideration when designing experimental and clinical studies in HIV-1-infected populations.

  11. HIV-1 envelope glycoprotein

    DOEpatents

    Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

    2017-08-22

    The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

  12. Psychoneuroimmunology and HIV-1.

    ERIC Educational Resources Information Center

    Antoni, Michael H.; And Others

    1990-01-01

    Presents evidence describing benefits of behavioral interventions such as aerobic exercise training on both psychological and immunological functioning among high risk human immunodeficiency virus-Type 1 (HIV-1) seronegative and very early stage seropositive homosexual men. HIV-1 infection is cast as chronic disease for which early…

  13. The Genome of Yoka Poxvirus

    PubMed Central

    Zhao, Guoyan; Droit, Lindsay; Tesh, Robert B.; Popov, Vsevolod L.; Little, Nicole S.; Upton, Chris; Virgin, Herbert W.; Wang, David

    2011-01-01

    Yoka poxvirus was isolated almost four decades ago from a mosquito pool in the Central African Republic. Its classification as a poxvirus is based solely upon the morphology of virions visualized by electron microscopy. Here we describe sequencing of the Yoka poxvirus genome using a combination of Roche/454 and Illumina next-generation sequencing technologies. A single consensus contig of ∼175 kb in length that encodes 186 predicted genes was generated. Multiple methods were used to show that Yoka poxvirus is most closely related to viruses in the Orthopoxvirus genus, but it is clearly distinct from previously described poxviruses. Collectively, the phylogenetic and genomic sequence analyses suggest that Yoka poxvirus is the prototype member of a new genus in the family Poxviridae. PMID:21813608

  14. Cell-Mediated Immune Predictors of Vaccine Effect on Viral Load and CD4 Count in a Phase 2 Therapeutic HIV-1 Vaccine Clinical Trial.

    PubMed

    Huang, Yunda; Pantaleo, Giuseppe; Tapia, Gonzalo; Sanchez, Brittany; Zhang, Lily; Trondsen, Monica; Hovden, Arnt-Ove; Pollard, Richard; Rockstroh, Jürgen; Ökvist, Mats; Sommerfelt, Maja A

    2017-09-22

    In a placebo-controlled trial of the peptide-based therapeutic HIV-1 p24(Gag) vaccine candidate Vacc-4x, participants on combination antiretroviral therapy (cART) received six immunizations over 18weeks, followed by analytical treatment interruption (ATI) between weeks 28 and 52. Cell-mediated immune responses were investigated as predictors of Vacc-4x effect (VE) on viral load (VL) and CD4 count during ATI. All analyses of week 28 responses and fold-changes relative to baseline considered per-protocol participants (Vacc-4x:placebo=72:32) resuming cART after week 40. Linear regression models with interaction tests were used. VE was estimated as the Vacc-4x-placebo difference in log10-transformed VL (VE(VL)) or CD4 count (VE(CD4)). A lower fold-change of CD4+ T-cell proliferation was associated with VE(CD4) at week 48 (p=0.036, multiplicity adjusted q=0.036) and week 52 (p=0.040, q=0.080). A higher fold-change of IFN-γ in proliferation supernatants was associated with VE(VL) at week 44 (p=0.047, q=0.07). A higher fold-change of TNF-α was associated with VE(VL) at week 44 (p=0.045, q=0.070), week 48 (p=0.028, q=0.070), and week 52 (p=0.037, q=0.074). A higher fold-change of IL-6 was associated with VE(VL) at week 48 (p=0.017, q=0.036). TNF-α levels (>median) were associated with VE(CD4) at week 48 (p=0.009, q=0.009). These exploratory analyses highlight the potential value of investigating biomarkers in T-cell proliferation supernatants for VE in clinical studies. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  15. B cell depletion in HIV-1 subtype A infected Ugandan adults: relationship to CD4 T cell count, viral load and humoral immune responses.

    PubMed

    Oballah, Peter; Flach, Britta; Eller, Leigh A; Eller, Michael A; Ouma, Benson; de Souza, Mark; Kibuuka, Hannah N; Wabwire-Mangen, Fred; Brown, Bruce K; Michael, Nelson L; Robb, Merlin L; Montefiori, David; Polonis, Victoria R

    2011-01-01

    To better understand the nature of B cell dysfunctions in subjects infected with HIV-1 subtype A, a rural cohort of 50 treatment-naïve Ugandan patients chronically infected with HIV-1 subtype A was studied, and the relationship between B cell depletion and HIV disease was assessed. B cell absolute counts were found to be significantly lower in HIV-1+ patients, when compared to community matched negative controls (p<0.0001). HIV-1-infected patients displayed variable functional and binding antibody titers that showed no correlation with viral load or CD4+ T cell count. However, B cell absolute counts were found to correlate inversely with neutralizing antibody (NAb) titers against subtype A (p = 0.05) and subtype CRF02_AG (p = 0.02) viruses. A positive correlation was observed between subtype A gp120 binding antibody titers and NAb breadth (p = 0.02) and mean titer against the 10 viruses (p = 0.0002). In addition, HIV-1 subtype A sera showed preferential neutralization of the 5 subtype A or CRF02_AG pseudoviruses, as compared with 5 pseudoviruses from subtypes B, C or D (p<0.001). These data demonstrate that in patients with chronic HIV-1 subtype A infection, significant B cell depletion can be observed, the degree of which does not appear to be associated with a decrease in functional antibodies. These findings also highlight the potential importance of subtype in the specificity of cross-clade neutralization in HIV-1 infection.

  16. Substance abuse, HIV-1 and hepatitis

    PubMed Central

    Parikh, Nirzari; Nonnemacher, Michael R.; Pirrone, Vanessa; Block, Timothy; Mehta, Anand; Wigdahl, Brian

    2013-01-01

    During the course of human immunodeficiency virus type 1 (HIV-1) disease, the virus has been shown to effectively escape the immune response with the subsequent establishment of latent viral reservoirs in specific cell populations within the peripheral blood (PB) and associated lymphoid tissues, bone marrow (BM), brain, and potentially other end organs. HIV-1, along with hepatitis B and C viruses (HBV and HCV), are known to share similar routes of transmission, including intravenous drug use, blood transfusions, sexual intercourse, and perinatal exposure. Substance abuse, including the use of opioids and cocaine, is a significant risk factor for exposure to HIV-1 and the development of acquired immune deficiency syndrome, as well as HBV and HCV exposure, infection, and disease. Thus, coinfection with HIV-1 and HBV or HCV is common and may be impacted by chronic substance abuse during the course of disease. HIV-1 impacts the natural course of HBV and HCV infection by accelerating the progression of HBV/HCV-associated liver disease toward end-stage cirrhosis and quantitative depletion of the CD4+ T-cell compartment. HBV or HCV coinfection with HIV-1 is also associated with increased mortality when compared to either infection alone. This review focuses on the impact of substance abuse and coinfection with HBV and HCV in the PB, BM, and brain on the HIV-1 pathogenic process as it relates to viral pathogenesis, disease progression, and the associated immune response during the course of this complex interplay. The impact of HIV-1 and substance abuse on hepatitis virus-induced disease is also a focal point. PMID:22973853

  17. Substance abuse, HIV-1 and hepatitis.

    PubMed

    Parikh, Nirzari; Nonnemacher, Michael R; Pirrone, Vanessa; Block, Timothy; Mehta, Anand; Wigdahl, Brian

    2012-10-01

    During the course of human immunodeficiency virus type 1 (HIV-1) disease, the virus has been shown to effectively escape the immune response with the subsequent establishment of latent viral reservoirs in specific cell populations within the peripheral blood (PB) and associated lymphoid tissues, bone marrow (BM), brain, and potentially other end organs. HIV-1, along with hepatitis B and C viruses (HBV and HCV), are known to share similar routes of transmission, including intravenous drug use, blood transfusions, sexual intercourse, and perinatal exposure. Substance abuse, including the use of opioids and cocaine, is a significant risk factor for exposure to HIV-1 and the development of acquired immune deficiency syndrome, as well as HBV and HCV exposure, infection, and disease. Thus, coinfection with HIV-1 and HBV or HCV is common and may be impacted by chronic substance abuse during the course of disease. HIV- 1 impacts the natural course of HBV and HCV infection by accelerating the progression of HBV/HCV-associated liver disease toward end-stage cirrhosis and quantitative depletion of the CD4+ T-cell compartment. HBV or HCV coinfection with HIV-1 is also associated with increased mortality when compared to either infection alone. This review focuses on the impact of substance abuse and coinfection with HBV and HCV in the PB, BM, and brain on the HIV-1 pathogenic process as it relates to viral pathogenesis, disease progression, and the associated immune response during the course of this complex interplay. The impact of HIV-1 and substance abuse on hepatitis virus-induced disease is also a focal point.

  18. Membrane fusion during poxvirus entry.

    PubMed

    Moss, Bernard

    2016-12-01

    Poxviruses comprise a large family of enveloped DNA viruses that infect vertebrates and invertebrates. Poxviruses, unlike most DNA viruses, replicate in the cytoplasm and encode enzymes and other proteins that enable entry, gene expression, genome replication, virion assembly and resistance to host defenses. Entry of vaccinia virus, the prototype member of the family, can occur at the plasma membrane or following endocytosis. Whereas many viruses encode one or two proteins for attachment and membrane fusion, vaccinia virus encodes four proteins for attachment and eleven more for membrane fusion and core entry. The entry-fusion proteins are conserved in all poxviruses and form a complex, known as the Entry Fusion Complex (EFC), which is embedded in the membrane of the mature virion. An additional membrane that encloses the mature virion and is discarded prior to entry is present on an extracellular form of the virus. The EFC is held together by multiple interactions that depend on nine of the eleven proteins. The entry process can be divided into attachment, hemifusion and core entry. All eleven EFC proteins are required for core entry and at least eight for hemifusion. To mediate fusion the virus particle is activated by low pH, which removes one or more fusion repressors that interact with EFC components. Additional EFC-interacting fusion repressors insert into cell membranes and prevent secondary infection. The absence of detailed structural information, except for two attachment proteins and one EFC protein, is delaying efforts to determine the fusion mechanism.

  19. Lessons from HIV-1 vaccine efficacy trials.

    PubMed

    Excler, Jean-Louis; Michael, Nelson L

    2016-11-01

    Only four HIV-1 vaccine concepts have been tested in six efficacy trials with no product licensed to date. Several scientific and programmatic lessons can be learned from these studies generating new hypotheses and guiding future steps. RV144 [ALVAC-HIV (canarypox vector) and AIDSVAX B/E (bivalent gp120 HIV-1 subtype B and CRF01_AE)] remains the only efficacy trial that demonstrated a modest vaccine efficacy, which led to the identification of immune correlates of risk. Progress on subtype-specific, ALVAC (canarypox vector) and gp120 vaccine prime-boost approaches has been slow, but we are finally close to the launch of an efficacy study in Africa in 2016. The quest of a globally effective HIV-1 vaccine has led to the development of new approaches. Efficacy studies of combinations of Adenovirus type 26 (Ad26)/Modified Vaccinia Ankara (MVA)/gp140 vaccines with mosaic designs will enter efficacy studies mid-2017 and cytomegalovirus (CMV)-vectored vaccines begin Phase I studies at the same time. Future HIV-1 vaccine efficacy trials face practical challenges as effective nonvaccine prevention programs are projected to decrease HIV-1 incidence. An HIV-1 vaccine is urgently needed. Increased industry involvement, mobilization of resources, expansion of a robust pipeline of new concepts, and robust preclinical challenge studies will be essential to accelerate efficacy testing of next generation HIV-1 vaccine candidates.

  20. High Frequency of Transmitted HIV-1 Gag HLA Class I-Driven Immune Escape Variants but Minimal Immune Selection over the First Year of Clade C Infection

    PubMed Central

    Gounder, Kamini; Padayachi, Nagavelli; Mann, Jaclyn K.; Radebe, Mopo; Mokgoro, Mammekwa; van der Stok, Mary; Mkhize, Lungile; Mncube, Zenele; Jaggernath, Manjeetha; Reddy, Tarylee; Walker, Bruce D.; Ndung’u, Thumbi

    2015-01-01

    In chronic HIV infection, CD8+ T cell responses to Gag are associated with lower viral loads, but longitudinal studies of HLA-restricted CD8+ T cell-driven selection pressure in Gag from the time of acute infection are limited. In this study we examined Gag sequence evolution over the first year of infection in 22 patients identified prior to seroconversion. A total of 310 and 337 full-length Gag sequences from the earliest available samples (median = 14 days after infection [Fiebig stage I/II]) and at one-year post infection respectively were generated. Six of 22 (27%) individuals were infected with multiple variants. There was a trend towards early intra-patient viral sequence diversity correlating with viral load set point (p = 0.07, r = 0.39). At 14 days post infection, 59.7% of Gag CTL epitopes contained non-consensus polymorphisms and over half of these (35.3%) comprised of previously described CTL escape variants. Consensus and variant CTL epitope proportions were equally distributed irrespective of the selecting host HLA allele and most epitopes remained unchanged over 12 months post infection. These data suggest that intrapatient diversity during acute infection is an indicator of disease outcome. In this setting, there is a high rate of transmitted CTL escape variants and limited immune selection in Gag during the first year of infection. These data have relevance for vaccine strategies designed to elicit effective CD8+ T cell immune responses. PMID:25781986

  1. Inflammatory colonic innate lymphoid cells are increased during untreated hiv-1 infection and associated with markers of gut dysbiosis and mucosal immune activation.

    PubMed

    Dillon, Stephanie M; Castleman, Moriah J; Frank, Daniel N; Austin, Gregory L; Gianella, Sara; Cogswell, Andrew C; Landay, Alan L; Barker, Edward; Wilson, Cara C

    2017-08-18

    HIV-1 infection is associated with intestinal inflammation, changes in the enteric microbiota (dysbiosis) and intestinal epithelial cell (IEC) damage. NKp44 innate lymphoid cells (ILCs) play an important role in epithelial barrier maintenance via the production of IL-22, but also display functional plasticity and can produce inflammatory cytokines (e.g. IFNg) in response to cytokine milieu and stimulatory signals. The objective of this pilot study was to enumerate frequencies of IL-22 and IFNg-expressing colonic NKp44 ILCs during untreated, chronic HIV-1 infection. A cross-sectional study was performed to compare numbers of cytokine-expressing ILCs in colonic biopsies of untreated, chronic HIV-1 infected (n=22) and uninfected (n=10) study participants. Associations between cytokine ILC and previously established measures of virological, immunological and microbiome indices were analyzed. Multi-color flow cytometry was used to measure the absolute number of colonic CD3NKp44CD56 ILCs expressing IL-22 or IFNg following in vitro mitogenic stimulation. Numbers of colonic NKp44 ILCs that expressed IFNg were significantly higher in HIV-1 infected versus uninfected persons and positively correlated with relative abundances of dysbiotic bacterial species in the Xanthomoadaceae and Prevotellaceae bacterial families and with colonic mDC and T cell activation. Higher numbers of inflammatory colonic ILCs during untreated chronic HIV-1 infection that associated with dysbiosis and colonic mDC and T cell activation suggest that inflammatory ILCs may contribute to gut mucosal inflammation and epithelial barrier breakdown, important features of HIV-1 mucosal pathogenesis.

  2. Selective induction of cell-mediated immunity and protection of rhesus macaques from chronic SHIV{sub KU2} infection by prophylactic vaccination with a conserved HIV-1 envelope peptide-cocktail

    SciTech Connect

    Nehete, Pramod N.; Nehete, Bharti P.; Hill, Lori; Manuri, Pallavi R.; Baladandayuthapani, Veerabhadran; Feng Lei; Simmons, Johnny; Sastry, K. Jagannadha

    2008-01-05

    Infection of Indian-origin rhesus macaques by the simian human immunodeficiency virus (SHIV) is considered to be a suitable preclinical model for directly testing efficacy of vaccine candidates based on the HIV-1 envelope. We used this model for prophylactic vaccination with a peptide-cocktail comprised of highly conserved HIV-1 envelope sequences immunogenic/antigenic in macaques and humans. Separate groups of macaques were immunized with the peptide-cocktail by intravenous and subcutaneous routes using autologous dendritic cells (DC) and Freund's adjuvant, respectively. The vaccine elicited antigen specific IFN-{gamma}-producing cells and T-cell proliferation, but not HIV-neutralizing antibodies. The vaccinated animals also exhibited efficient cross-clade cytolytic activity against target cells expressing envelope proteins corresponding to HIV-1 strains representative of multiple clades that increased after intravenous challenge with pathogenic SHIV{sub KU2}. Virus-neutralizing antibodies were either undetectable or present only transiently at low levels in the control as well as vaccinated monkeys after infection. Significant control of plasma viremia leading to undetectable levels was achieved in majority of vaccinated monkeys compared to mock-vaccinated controls. Monkeys vaccinated with the peptide-cocktail using autologous DC, compared to Freund's adjuvant, and the mock-vaccinated animals, showed significantly higher IFN-{gamma} production, higher levels of vaccine-specific IFN-{gamma} producing CD4{sup +} cells and significant control of plasma viremia. These results support DC-based vaccine delivery and the utility of the conserved HIV-1 envelope peptide-cocktail, capable of priming strong cell-mediated immunity, for potential inclusion in HIV vaccination strategies.

  3. Immune deficiency could be an early risk factor for altered insulin sensitivity in antiretroviral-naive HIV-1-infected patients: the ANRS COPANA cohort.

    PubMed

    Boufassa, Faroudy; Goujard, Cécile; Viard, Jean-Paul; Carlier, Robert; Lefebvre, Bénédicte; Yeni, Patrick; Bouchaud, Olivier; Capeau, Jacqueline; Meyer, Laurence; Vigouroux, Corinne

    2012-01-01

    The relationships between immunovirological status, inflammatory markers, insulin resistance and fat distribution have not been studied in recently diagnosed (<1 year) antiretroviral-naive HIV-1-infected patients. We studied 214 antiretroviral-naive patients at enrolment in the metabolic substudy of the ANRS COPANA cohort. We measured clinical, immunovirological and inflammatory parameters, glucose/insulin during oral glucose tolerance test (OGTT), adipokines, subcutaneous and visceral fat surfaces (subcutaneous adipose tissue [SAT] and visceral adipose tissue [VAT], assessed by computed tomography) and the body fat distribution based on dual-energy X-ray absorptiometry (DEXA). Median age was 36 years; 28% of the patients were female and 35% of sub-Saharan origin; 20% had low CD4(+) T-cell counts (≤200/mm(3)). Patients with low CD4(+) T-cell counts were older and more frequently of sub-Saharan Africa origin, had lower body mass index (BMI) but no different SAT/VAT ratio and fat distribution than other patients. They also had lower total, low-density lipoprotein and high-density lipoprotein cholesterolaemia, higher triglyceridaemia and post-OGTT glycaemia, higher markers of insulin resistance (insulin during OGTT and homeostasis model assessment of insulin resistance) and of inflammation (high-sensitivity C-reactive protein, IL-6, tumour necrosis factor (TNF)-α, sTNFR1 and sTNFR2). After adjustment for age, sex, geographic origin, BMI and waist circumference, increased insulin resistance was not related to any inflammatory marker. In multivariate analysis, low CD4(+) T-cell count was an independent risk factor for altered insulin sensitivity (β-coefficient for HOMA-IR: +0.90; P=0.001; CD4(+) T-cell count >500/mm(3) as the reference), in addition to older age (β: +0.26 for a 10-year increase; P=0.01) and higher BMI (β: +0.07 for a 1-kg/m(2) increase; P=0.003). In ART-naive patients, severe immune deficiency but not inflammation could be an early risk factor for

  4. Immune Reconstitution in Severely Immunosuppressed Antiretroviral-Naive HIV-1-Infected Patients Starting Efavirenz, Lopinavir-Ritonavir, or Atazanavir-Ritonavir Plus Tenofovir/Emtricitabine: Final 48-Week Results (The Advanz-3 Trial).

    PubMed

    Miro, Jose M; Manzardo, Christian; Ferrer, Elena; Loncà, Montserrat; Guardo, Alberto C; Podzamczer, Daniel; Domingo, Pere; Curran, Adrian; Clotet, Bonaventura; Cruceta, Anna; Lozano, Francisco; Pérez, Iñaki; Plana, Montserrat; Gatell, Jose M

    2015-06-01

    Few randomized clinical trials have investigated antiretroviral regimens in very advanced HIV-1-infected patients. The objective was to study the immune reconstitution in very immunosuppressed antiretroviral-naive, HIV-1-infected individuals by comparing an efavirenz-based regimen with 2 ritonavir-boosted protease inhibitor regimens. Randomized, controlled, open-label, multicenter clinical trial. Eighty-nine HIV-1-infected antiretroviral-naive patients with <100 CD4 cells per cubic millimeter were randomly assigned in a 1:1:1 ratio to efavirenz (n = 29), atazanavir/ritonavir (n = 30), or lopinavir/ritonavir (n = 30) combined with tenofovir plus emtricitabine. The primary outcome was median increase in CD4 cell count at week 48. Secondary end points were the proportion of patients with HIV-1 RNA <50 copies per milliliter, adverse events, disease progression, and death. In the on-treatment analysis, the median (interquartile range) increase in the CD4 count after 48 weeks was +193 (129-349) cells per microliter in the efavirenz arm, +197 (146-238) cells per microliter in the ritonavir-boosted atazanavir arm, and +205 (178-327) cells per microliter in the ritonavir-boosted lopinavir arm (P = 0.73). The percentage of patients achieving viral suppression was similar in all 3 treatment arms at 48 weeks {efavirenz, 85.71% [95% confidence interval (CI): 68.5 to 94.3]; atazanavir, 80% [95% CI: 62.7 to 90.5]; and lopinavir, 82.8% [95% CI: 65.5 to 92.4]; P = 0.88}. Bacterial translocation, inflammation, immune activation, and apoptotic markers, but not D-dimer, declined significantly and similarly in the 3 treatment arms. Adverse events had a similar incidence in all 3 antiretroviral regimens. No patients died. The immune reconstitution induced by an efavirenz-based regimen in very advanced HIV-1-infected patients was similar to that induced by a ritonavir-boosted protease inhibitor-based regimen (ClinicalTrials.gov registration number: NCT00532168).

  5. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development

    DOE PAGES

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; ...

    2014-11-14

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth ofmore » IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.« less

  6. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development

    SciTech Connect

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T.; Barouch, Dan H.

    2014-11-14

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.

  7. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development.

    PubMed

    Stephenson, Kathryn E; Neubauer, George H; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T; Barouch, Dan H

    2015-01-01

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research. Copyright © 2014. Published by Elsevier B.V.

  8. Quantification of the Epitope Diversity of HIV-1-Specific Binding Antibodies by Peptide Microarrays for Global HIV-1 Vaccine Development

    PubMed Central

    Stephenson, Kathryn E.; Neubauer, George H.; Reimer, Ulf; Pawlowski, Nikolaus; Knaute, Tobias; Zerweck, Johannes; Korber, Bette T.; Barouch, Dan H.

    2014-01-01

    An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6,564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research. PMID:25445329

  9. Semen Bacterial Concentrations and HIV-1 RNA Shedding Among HIV-1–Seropositive Kenyan Men

    PubMed Central

    Srinivasan, Sujatha; Huang, Dandi; Ko, Daisy L.; Sanders, Eduard J.; Peshu, Norbert M.; Krieger, John N.; Muller, Charles H.; Coombs, Robert W.; Fredricks, David N.; Graham, Susan M.

    2017-01-01

    Introduction: HIV-1 is transmitted through semen from men to their sexual partners. Genital infections can increase HIV-1 RNA shedding in semen, but shedding also occurs in the absence of typical pathogens. We hypothesized that higher bacterial concentrations in semen would be associated with higher HIV-1 RNA levels. Methods: We analyzed semen samples from 42 HIV-1–seropositive Kenyan men using quantitative polymerase chain reaction (PCR) to assess bacterial concentrations and real-time PCR to measure HIV-1 RNA levels. Generalized estimation equations were used to evaluate associations between these 2 measures. Broad-range 16S rRNA gene PCR with pyrosequencing was performed on a subset of 13 samples to assess bacterial community composition. Results: Bacteria were detected in 96.6% of 88 samples by quantitative PCR. Semen bacterial concentration and HIV-1 RNA levels were correlated 0.30 (P = 0.01). The association between bacterial concentration and HIV-1 RNA detection was not significant after adjustment for antiretroviral therapy (ART) (adjusted odds ratio: 1.27, 95% CI: 0.84 to 1.91). Factors associated with semen bacterial concentration included insertive anal sex (adjusted beta 0.92, 95% CI: 0.12 to 1.73) and ART use (adjusted beta: −0.77, 95% CI: −1.50 to 0.04). Among 13 samples with pyrosequencing data, Corynebacterium spp., Staphylococcus spp., and Streptococcus spp. were most frequently detected. Conclusion: Most of these HIV-1–infected men had bacteria in their semen. ART use was associated with undetectable semen HIV-1 RNA and lower semen bacterial concentrations, whereas insertive anal sex was associated with higher bacterial concentrations. Additional studies evaluating the relationship between semen bacteria, inflammation, mucosal immunity, and HIV-1 shedding are needed to understand implications for HIV-1 transmission. PMID:27861240

  10. Fetal exposure to HIV-1 alters chemokine receptor expression by CD4+T cells and increases susceptibility to HIV-1.

    PubMed

    Bunders, Madeleine J; van Hamme, John L; Jansen, Machiel H; Boer, Kees; Kootstra, Neeltje A; Kuijpers, Taco W

    2014-10-24

    Absolute numbers of lymphocytes are decreased in uninfected infants born to HIV-1-infected women (HIV-1-exposed). Although the exact mechanism is unknown, fetal exposure to maternal HIV-1-infection could prime the immune system and affect T cell trafficking. We compared the expression of chemokine receptors on cord blood CD4(+) T cells from HIV-1-exposed children and healthy controls. At baseline CD4(+) T cells had a largely naïve phenotype. However, stimulation with cytokines resulted in an upregulation of inflammatory response-related chemokine receptors on CD4(+) T cells, with HIV-1-exposed infants having a significantly higher frequency of CD4(+) T cells expressing, in particularly Th2 associated chemokine receptors (CCR3 p < 0.01, CCR8 p = 0.03). Numbers of naive CCR7(+) CD4(+) T cells were reduced (p = 0.01) in HIV-1-exposed infants. We further assessed whether the inflammatory phenotype was associated with susceptibility to HIV-1 and detected higher levels of p24 upon in in vitro infection of stimulated CD4(+) T cells of HIV-1-exposed infants. In summary, fetal exposure to HIV-1 primes the immune system in the infant leading to an enhanced immune activation and altered T cell homing, with potential ramifications regarding T cell responses and the acquisition of HIV-1 as an infant.

  11. Short Communication: Neutralizing Antibodies in HIV-1-Infected Brazilian Individuals

    PubMed Central

    Morgado, Mariza Gonçalvez; Côrtes, Fernanda Heloise; Guimarães, Monick Lindermeyer; Mendonça-Lima, Leila; Pilotto, Jose Henrique; Grinsztejn, Beatriz; Veloso, Valdiléa Gonçalves; Bongertz, Vera

    2013-01-01

    Abstract Tests for the detection of the humoral immune response to HIV-1 have to be standardized and established, demanding regional efforts. For this purpose the neutralizing antibody (NAb) assay for HIV-1 in TZM-bl cells was introduced in Brazil. Twenty plasma samples from HIV-1-infected individuals were assayed: 10 progressors and 10 long-term nonprogressors. These were tested against eight env-pseudotyped viruses (psVs) in the TZM-bl NAb assay and against HIV-1 strain HTLV/IIIB (HIV-1 IIIB) in primary lymphocytes. Forty-four percent of the samples showed neutralizing titers for psVs and 55% for HIV-1 IIIB. Plasma from progressors showed a broader neutralization and a higher potency. The introduction of these reference reagents encourages the participation of Brazil in future comparative assessments of anti-HIV-1 antibodies. PMID:23145941

  12. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules.

    PubMed

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S Y

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This "shock" approach is then followed by "kill" of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells.

  13. Specific Elimination of Latently HIV-1 Infected Cells Using HIV-1 Protease-Sensitive Toxin Nanocapsules

    PubMed Central

    Wen, Jing; Yan, Ming; Liu, Yang; Li, Jie; Xie, Yiming; Lu, Yunfeng; Kamata, Masakazu; Chen, Irvin S. Y.

    2016-01-01

    Anti-retroviral drugs suppress HIV-1 plasma viremia to undetectable levels; however, latent HIV-1 persists in reservoirs within HIV-1-infected patients. The silent provirus can be activated through the use of drugs, including protein kinase C activators and histone deacetylase inhibitors. This “shock” approach is then followed by “kill” of the producing cells either through direct HIV-1-induced cell death or natural immune mechanisms. However, these mechanisms are relatively slow and effectiveness is unclear. Here, we develop an approach to specifically target and kill cells that are activated early in the process of virus production. We utilize a novel nanocapsule technology whereby the ricin A chain is encapsulated in an inactive form within a polymer shell. Specificity for release of the ricin A toxin is conferred by peptide crosslinkers that are sensitive to cleavage by HIV-1 protease. By using well-established latent infection models, J-Lat and U1 cells, we demonstrate that only within an HIV-1-producing cell expressing functional HIV-1 protease will the nanocapsule release its ricin A cargo, shutting down viral and cellular protein synthesis, and ultimately leading to rapid death of the producer cell. Thus, we provide proof of principle for a novel technology to kill HIV-1-producing cells without effects on non-target cells. PMID:27049645

  14. Poxviruses in Bats … so What?

    PubMed Central

    Baker, Kate S.; Murcia, Pablo R.

    2014-01-01

    Poxviruses are important pathogens of man and numerous domestic and wild animal species. Cross species (including zoonotic) poxvirus infections can have drastic consequences for the recipient host. Bats are a diverse order of mammals known to carry lethal viral zoonoses such as Rabies, Hendra, Nipah, and SARS. Consequent targeted research is revealing bats to be infected with a rich diversity of novel viruses. Poxviruses were recently identified in bats and the settings in which they were found were dramatically different. Here, we review the natural history of poxviruses in bats and highlight the relationship of the viruses to each other and their context in the Poxviridae family. In addition to considering the zoonotic potential of these viruses, we reflect on the broader implications of these findings. Specifically, the potential to explore and exploit this newfound relationship to study coevolution and cross species transmission together with fundamental aspects of poxvirus host tropism as well as bat virology and immunology. PMID:24704730

  15. Interleukin-1- and Type I Interferon-Dependent Enhanced Immunogenicity of an NYVAC-HIV-1 Env-Gag-Pol-Nef Vaccine Vector with Dual Deletions of Type I and Type II Interferon-Binding Proteins

    PubMed Central

    Delaloye, Julie; Filali-Mouhim, Abdelali; Cameron, Mark J.; Haddad, Elias K.; Harari, Alexandre; Goulet, Jean-Pierre; Gomez, Carmen E.; Perdiguero, Beatriz; Esteban, Mariano; Pantaleo, Giuseppe; Roger, Thierry; Sékaly, Rafick-Pierre

    2015-01-01

    ABSTRACT NYVAC, a highly attenuated, replication-restricted poxvirus, is a safe and immunogenic vaccine vector. Deletion of immune evasion genes from the poxvirus genome is an attractive strategy for improving the immunogenic properties of poxviruses. Using systems biology approaches, we describe herein the enhanced immunological profile of NYVAC vectors expressing the HIV-1 clade C env, gag, pol, and nef genes (NYVAC-C) with single or double deletions of genes encoding type I (ΔB19R) or type II (ΔB8R) interferon (IFN)-binding proteins. Transcriptomic analyses of human monocytes infected with NYVAC-C, NYVAC-C with the B19R deletion (NYVAC-C-ΔB19R), or NYVAC-C with B8R and B19R deletions (NYVAC-C-ΔB8RB19R) revealed a concerted upregulation of innate immune pathways (IFN-stimulated genes [ISGs]) of increasing magnitude with NYVAC-C-ΔB19R and NYVAC-C-ΔB8RB19R than with NYVAC-C. Deletion of B8R and B19R resulted in an enhanced activation of IRF3, IRF7, and STAT1 and the robust production of type I IFNs and of ISGs, whose expression was inhibited by anti-type I IFN antibodies. Interestingly, NYVAC-C-ΔB8RB19R induced the production of much higher levels of proinflammatory cytokines (tumor necrosis factor [TNF], interleukin-6 [IL-6], and IL-8) than NYVAC-C or NYVAC-C-ΔB19R as well as a strong inflammasome response (caspase-1 and IL-1β) in infected monocytes. Top network analyses showed that this broad response mediated by the deletion of B8R and B19R was organized around two upregulated gene expression nodes (TNF and IRF7). Consistent with these findings, monocytes infected with NYVAC-C-ΔB8RB19R induced a stronger type I IFN-dependent and IL-1-dependent allogeneic CD4+ T cell response than monocytes infected with NYVAC-C or NYVAC-C-ΔB19R. Dual deletion of type I and type II IFN immune evasion genes in NYVAC markedly enhanced its immunogenic properties via its induction of the increased expression of type I IFNs and IL-1β and make it an attractive candidate HIV

  16. Interleukin-1- and type I interferon-dependent enhanced immunogenicity of an NYVAC-HIV-1 Env-Gag-Pol-Nef vaccine vector with dual deletions of type I and type II interferon-binding proteins.

    PubMed

    Delaloye, Julie; Filali-Mouhim, Abdelali; Cameron, Mark J; Haddad, Elias K; Harari, Alexandre; Goulet, Jean-Pierre; Gomez, Carmen E; Perdiguero, Beatriz; Esteban, Mariano; Pantaleo, Giuseppe; Roger, Thierry; Sékaly, Rafick-Pierre; Calandra, Thierry

    2015-04-01

    NYVAC, a highly attenuated, replication-restricted poxvirus, is a safe and immunogenic vaccine vector. Deletion of immune evasion genes from the poxvirus genome is an attractive strategy for improving the immunogenic properties of poxviruses. Using systems biology approaches, we describe herein the enhanced immunological profile of NYVAC vectors expressing the HIV-1 clade C env, gag, pol, and nef genes (NYVAC-C) with single or double deletions of genes encoding type I (ΔB19R) or type II (ΔB8R) interferon (IFN)-binding proteins. Transcriptomic analyses of human monocytes infected with NYVAC-C, NYVAC-C with the B19R deletion (NYVAC-C-ΔB19R), or NYVAC-C with B8R and B19R deletions (NYVAC-C-ΔB8RB19R) revealed a concerted upregulation of innate immune pathways (IFN-stimulated genes [ISGs]) of increasing magnitude with NYVAC-C-ΔB19R and NYVAC-C-ΔB8RB19R than with NYVAC-C. Deletion of B8R and B19R resulted in an enhanced activation of IRF3, IRF7, and STAT1 and the robust production of type I IFNs and of ISGs, whose expression was inhibited by anti-type I IFN antibodies. Interestingly, NYVAC-C-ΔB8RB19R induced the production of much higher levels of proinflammatory cytokines (tumor necrosis factor [TNF], interleukin-6 [IL-6], and IL-8) than NYVAC-C or NYVAC-C-ΔB19R as well as a strong inflammasome response (caspase-1 and IL-1β) in infected monocytes. Top network analyses showed that this broad response mediated by the deletion of B8R and B19R was organized around two upregulated gene expression nodes (TNF and IRF7). Consistent with these findings, monocytes infected with NYVAC-C-ΔB8RB19R induced a stronger type I IFN-dependent and IL-1-dependent allogeneic CD4(+) T cell response than monocytes infected with NYVAC-C or NYVAC-C-ΔB19R. Dual deletion of type I and type II IFN immune evasion genes in NYVAC markedly enhanced its immunogenic properties via its induction of the increased expression of type I IFNs and IL-1β and make it an attractive candidate HIV

  17. Protective Efficacy of a Global HIV-1 Mosaic Vaccine Against Heterologous SHIV Challenges in Rhesus Monkeys

    PubMed Central

    Barouch, Dan H.; Stephenson, Kathryn E.; Borducchi, Erica N.; Smith, Kaitlin; Stanley, Kelly; McNally, Anna G.; Liu, Jinyan; Abbink, Peter; Maxfield, Lori F.; Seaman, Michael S.; Dugast, Anne-Sophie; Alter, Galit; Ferguson, Melissa; Li, Wenjun; Earl, Patricia L.; Moss, Bernard; Giorgi, Elena E.; Szinger, James J.; Eller, Leigh Anne; Billings, Erik A.; Rao, Mangala; Tovanabutra, Sodsai; Sanders-Buell, Eric; Weijtens, Mo; Pau, Maria G.; Schuitemaker, Hanneke; Robb, Merlin L.; Kim, Jerome H.; Korber, Bette T.; Michael, Nelson L.

    2013-01-01

    SUMMARY The global diversity of HIV-1 represents a critical challenge facing HIV-1 vaccine development. HIV-1 mosaic antigens are bioinformatically optimized immunogens designed for improved coverage of HIV-1 diversity. However, the protective efficacy of global HIV-1 vaccine antigens has not previously been evaluated. Here we demonstrate the capacity of bivalent HIV-1 mosaic antigens to protect rhesus monkeys against acquisition of heterologous challenges with the difficult-to-neutralize simian-human immunodeficiency virus SHIV-SF162P3. Adenovirus/poxvirus and adenovirus/adenovirus vector-based vaccines expressing HIV-1 mosaic Env, Gag, and Pol afforded a significant reduction in the per-exposure acquisition risk following repetitive, intrarectal SHIV-SF162P3 challenges. Protection against acquisition of infection was correlated with vaccine-elicited binding, neutralizing, and functional non-neutralizing antibodies. These data demonstrate the protective efficacy of HIV-1 mosaic antigens and suggest a potential strategy towards the development of a global HIV-1 vaccine. Moreover, our findings suggest that the coordinated activity of multiple antibody functions may contribute to protection against difficult-to-neutralize viruses. PMID:24243013

  18. Protective efficacy of a global HIV-1 mosaic vaccine against heterologous SHIV challenges in rhesus monkeys.

    PubMed

    Barouch, Dan H; Stephenson, Kathryn E; Borducchi, Erica N; Smith, Kaitlin; Stanley, Kelly; McNally, Anna G; Liu, Jinyan; Abbink, Peter; Maxfield, Lori F; Seaman, Michael S; Dugast, Anne-Sophie; Alter, Galit; Ferguson, Melissa; Li, Wenjun; Earl, Patricia L; Moss, Bernard; Giorgi, Elena E; Szinger, James J; Eller, Leigh Anne; Billings, Erik A; Rao, Mangala; Tovanabutra, Sodsai; Sanders-Buell, Eric; Weijtens, Mo; Pau, Maria G; Schuitemaker, Hanneke; Robb, Merlin L; Kim, Jerome H; Korber, Bette T; Michael, Nelson L

    2013-10-24

    The global diversity of HIV-1 represents a critical challenge facing HIV-1 vaccine development. HIV-1 mosaic antigens are bioinformatically optimized immunogens designed for improved coverage of HIV-1 diversity. However, the protective efficacy of such global HIV-1 vaccine antigens has not previously been evaluated. Here, we demonstrate the capacity of bivalent HIV-1 mosaic antigens to protect rhesus monkeys against acquisition of infection following heterologous challenges with the difficult-to-neutralize simian-human immunodeficiency virus SHIV-SF162P3. Adenovirus/poxvirus and adenovirus/adenovirus vector-based vaccines expressing HIV-1 mosaic Env, Gag, and Pol afforded a significant reduction in the per-exposure acquisition risk following repetitive, intrarectal SHIV-SF162P3 challenges. Protection against acquisition of infection correlated with vaccine-elicited binding, neutralizing, and functional nonneutralizing antibodies, suggesting that the coordinated activity of multiple antibody functions may contribute to protection against difficult-to-neutralize viruses. These data demonstrate the protective efficacy of HIV-1 mosaic antigens and suggest a potential strategy for the development of a global HIV-1 vaccine. PAPERCLIP: Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Survival of lethal poxvirus infection in mice depends on TLR9, and therapeutic vaccination provides protection

    PubMed Central

    Samuelsson, Christofer; Hausmann, Jürgen; Lauterbach, Henning; Schmidt, Michaela; Akira, Shizuo; Wagner, Hermann; Chaplin, Paul; Suter, Mark; O’Keeffe, Meredith; Hochrein, Hubertus

    2008-01-01

    Poxviruses such as the causative agent of smallpox have developed multiple strategies to suppress immune responses, including the suppression of DC activation. Since poxviruses are large DNA viruses, we hypothesized that their detection by DCs may involve the endosomal DNA recognition receptor TLR9. Indeed, we have shown here that DC recognition of ectromelia virus (ECTV), the causative agent of mousepox, completely depended on TLR9. The importance of TLR9 was highlighted by the fact that mice lacking TLR9 showed drastically increased susceptibility to infection with ECTV. In contrast, we found that the strongly attenuated poxvirus modified vaccinia virus Ankara (MVA) activated DCs by both TLR9-dependent and -independent pathways. We therefore tested whether we could use the broader induction of immune responses by MVA to protect mice from a lethal infection with ECTV. Indeed, MVA given at the same time as a lethal dose of ECTV protected mice from death. Importantly, MVA also rescued TLR9-deficient mice if administered 2 full days after an otherwise lethal infection with ECTV. Therefore, these data suggest an essential role for TLR9 in the defense against poxviruses. In addition, postexposure application of MVA may protect against lethal poxvirus infection. PMID:18398511

  20. Poxvirus targeting of E3 ligase β-TrCP by molecular mimicry: a mechanism to inhibit NF-κB activation and promote immune evasion and virulence.

    PubMed

    Mansur, Daniel S; Maluquer de Motes, Carlos; Unterholzner, Leonie; Sumner, Rebecca P; Ferguson, Brian J; Ren, Hongwei; Strnadova, Pavla; Bowie, Andrew G; Smith, Geoffrey L

    2013-02-01

    The transcription factor NF-κB is essential for immune responses against pathogens and its activation requires the phosphorylation, ubiquitination and proteasomal degradation of IκBα. Here we describe an inhibitor of NF-κB from vaccinia virus that has a closely related counterpart in variola virus, the cause of smallpox, and mechanistic similarity with the HIV protein Vpu. Protein A49 blocks NF-κB activation by molecular mimicry and contains a motif conserved in IκBα which, in IκBα, is phosphorylated by IKKβ causing ubiquitination and degradation. Like IκBα, A49 binds the E3 ligase β-TrCP, thereby preventing ubiquitination and degradation of IκBα. Consequently, A49 stabilised phosphorylated IκBα (p-IκBα) and its interaction with p65, so preventing p65 nuclear translocation. Serine-to-alanine mutagenesis within the IκBα-like motif of A49 abolished β-TrCP binding, stabilisation of p-IκBα and inhibition of NF-κB activation. Remarkably, despite encoding nine other inhibitors of NF-κB, a VACV lacking A49 showed reduced virulence in vivo.

  1. Adsorption of recombinant poxvirus L1-protein to aluminum hydroxide/CpG vaccine adjuvants enhances immune responses and protection of mice from vaccinia virus challenge.

    PubMed

    Xiao, Yuhong; Zeng, Yuhong; Alexander, Edward; Mehta, Shyam; Joshi, Sangeeta B; Buchman, George W; Volkin, David B; Middaugh, C Russell; Isaacs, Stuart N

    2013-01-02

    The stockpiling of live vaccinia virus vaccines has enhanced biopreparedness against the intentional or accidental release of smallpox. Ongoing research on future generation smallpox vaccines is providing key insights into protective immune responses as well as important information about subunit-vaccine design strategies. For protein-based recombinant subunit vaccines, the formulation and stability of candidate antigens with different adjuvants are important factors to consider for vaccine design. In this work, a non-tagged secreted L1-protein, a target antigen on mature virus, was expressed using recombinant baculovirus technology and purified. To identify optimal formulation conditions for L1, a series of biophysical studies was performed over a range of pH and temperature conditions. The overall physical stability profile was summarized in an empirical phase diagram. Another critical question to address for development of an adjuvanted vaccine was if immunogenicity and protection could be affected by the interactions and binding of L1 to aluminum salts (Alhydrogel) with and without a second adjuvant, CpG. We thus designed a series of vaccine formulations with different binding interactions between the L1 and the two adjuvants, and then performed a series of vaccination-challenge experiments in mice including measurement of antibody responses and post-challenge weight loss and survival. We found that better humoral responses and protection were conferred with vaccine formulations when the L1-protein was adsorbed to Alhydrogel. These data demonstrate that designing vaccine formulation conditions to maximize antigen-adjuvant interactions is a key factor in smallpox subunit-vaccine immunogenicity and protection. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Adsorption of recombinant poxvirus L1-protein to aluminum hydroxide/CpG vaccine adjuvants enhances immune responses and protection of mice from vaccinia virus challenge

    PubMed Central

    Xiao, Yuhong; Zeng, Yuhong; Alexander, Edward; Mehta, Shyam; Joshi, Sangeeta B.; Buchman, George W.; Volkin, David B.; Middaugh, C. Russell; Isaacs, Stuart N.

    2012-01-01

    The stockpiling of live vaccinia virus vaccines has enhanced biopreparedness against the intentional or accidental release of smallpox. Ongoing research on future generation smallpox vaccines is providing key insights into protective immune responses as well as important information about subunit vaccine design strategies. For protein-based recombinant subunit vaccines, the formulation and stability of candidate antigens with different adjuvants are important factors to consider for vaccine design. In this work, a non-tagged secreted L1-protein, a target antigen on mature virus, was expressed using recombinant baculovirus technology and purified. To identify optimal formulation conditions for L1, a series of biophysical studies was performed over a range of pH and temperature conditions. The overall physical stability profile was summarized in an empirical phase diagram. Another critical question to address for development of an adjuvanted-vaccine was if immunogenicity and protection could be affected by the interactions and binding of L1 to aluminum salts (Alhydrogel) with and without a second adjuvant, CpG. We thus designed a series of vaccine formulations with different binding interactions between the L1 and the two adjuvants, and then performed a series of vaccination-challenge experiments in mice including measurement of antibody responses and post-challenge weight-loss and survival. We found that better humoral responses and protection were conferred with vaccine formulations when the L1-protein was adsorbed to Alhydrogel. These data demonstrate that designing vaccine formulation conditions to maximize antigen-adjuvant interactions is a key factor in smallpox subunit vaccine immunogenicity and protection. PMID:23153450

  3. Comparative Evaluation of HIV-1 Neutralization in External Secretions and Sera of HIV-1-Infected Women.

    PubMed

    Wei, Qing; Moldoveanu, Zina; Huang, Wen-Qiang; Alexander, Rashada C; Goepfert, Paul A; Mestecky, Jiri

    2012-01-01

    Although human immunodeficiency virus type 1 (HIV-1)-specific antibodies are detectable in external secretions by ELISA and western blot (WB), the presence of HIV-1 neutralizing antibodies is difficult to evaluate due to the low levels of immunoglobulins (Ig) and the presence of humoral factors of innate immunity. The objective of this study was to determine virus neutralization activity and the relative contribution of HIV-1-specific antibodies of various isotypes to virus neutralization in serum/plasma samples, cervicovaginal lavages (CVL), and rectal lavages (RL). Serum/plasma, CVL, and RL samples were examined by ELISA, WB and HIV-1 neutralization assays. Selected samples were Ig depleted and analyzed for virus neutralization. IgG specific for three HIV-1 ENV antigens was detected in all serum/plasma samples, while IgA to at least one ENV glycoprotein was found at the low levels in 95% samples. Serum/plasma samples had the ability to neutralize at least one of three clade B and two clade C viruses. The neutralizing titers were reduced significantly or became undetectable after IgG removal. In corresponding CVL and RL, HIV-1 ENV-specific IgG antibodies were readily detected compared to IgA. Furthermore, IgG in CVL had greater ability than IgA to reduce virus infectivity. The difference in HIV-1 neutralization before and after Ig depletion was not observed in RL, implying that innate humoral factors were involved in anti-HIV-1 activity. Results demonstrate that HIV-1-specific neutralizing antibodies are almost exclusively of the IgG isotype in serum/plasma and CVL samples. HIV-1-specific binding antibodies detected in RL are not responsible for neutralization activity, suggesting that the antibody-mediated virus neutralization in external secretions should be verified by means of a selective depletion of Ig.

  4. Mosaic clade M human immunodeficiency virus type 1 (HIV-1) envelope immunogens

    DOEpatents

    Korber, Bette T.; Fischer, William; Liao, Hua-Xin; Haynes, Barton F.; Letvin, Norman; Hahn; Beatrice H.

    2011-05-31

    The present invention relates to mosaic clade M HIV-1 Env polypeptides and to compositions comprising same. The polypeptides of the invention are suitable for use in inducing an immune response to HIV-1 in a human.

  5. Poxvirus entry and membrane fusion

    SciTech Connect

    Moss, Bernard . E-mail: bmoss@nih.gov

    2006-01-05

    The study of poxvirus entry and membrane fusion has been invigorated by new biochemical and microscopic findings that lead to the following conclusions: (1) the surface of the mature virion (MV), whether isolated from an infected cell or by disruption of the membrane wrapper of an extracellular virion, is comprised of a single lipid membrane embedded with non-glycosylated viral proteins; (2) the MV membrane fuses with the cell membrane, allowing the core to enter the cytoplasm and initiate gene expression; (3) fusion is mediated by a newly recognized group of viral protein components of the MV membrane, which are conserved in all members of the poxvirus family; (4) the latter MV entry/fusion proteins are required for cell to cell spread necessitating the disruption of the membrane wrapper of extracellular virions prior to fusion; and furthermore (5) the same group of MV entry/fusion proteins are required for virus-induced cell-cell fusion. Future research priorities include delineation of the roles of individual entry/fusion proteins and identification of cell receptors.

  6. Worldwide Phylogenetic Relationship of Avian Poxviruses

    PubMed Central

    Foster, Jeffrey T.; Dán, Ádám; Ip, Hon S.; Egstad, Kristina F.; Parker, Patricia G.; Higashiguchi, Jenni M.; Skinner, Michael A.; Höfle, Ursula; Kreizinger, Zsuzsa; Dorrestein, Gerry M.; Solt, Szabolcs; Sós, Endre; Kim, Young Jun; Uhart, Marcela; Pereda, Ariel; González-Hein, Gisela; Hidalgo, Hector; Blanco, Juan-Manuel; Erdélyi, Károly

    2013-01-01

    Poxvirus infections have been found in 230 species of wild and domestic birds worldwide in both terrestrial and marine environments. This ubiquity raises the question of how infection has been transmitted and globally dispersed. We present a comprehensive global phylogeny of 111 novel poxvirus isolates in addition to all available sequences from GenBank. Phylogenetic analysis of the Avipoxvirus genus has traditionally relied on one gene region (4b core protein). In this study we expanded the analyses to include a second locus (DNA polymerase gene), allowing for a more robust phylogenetic framework, finer genetic resolution within specific groups, and the detection of potential recombination. Our phylogenetic results reveal several major features of avipoxvirus evolution and ecology and propose an updated avipoxvirus taxonomy, including three novel subclades. The characterization of poxviruses from 57 species of birds in this study extends the current knowledge of their host range and provides the first evidence of the phylogenetic effect of genetic recombination of avipoxviruses. The repeated occurrence of avian family or order-specific grouping within certain clades (e.g., starling poxvirus, falcon poxvirus, raptor poxvirus, etc.) indicates a marked role of host adaptation, while the sharing of poxvirus species within prey-predator systems emphasizes the capacity for cross-species infection and limited host adaptation. Our study provides a broad and comprehensive phylogenetic analysis of the Avipoxvirus genus, an ecologically and environmentally important viral group, to formulate a genome sequencing strategy that will clarify avipoxvirus taxonomy. PMID:23408635

  7. Worldwide phylogenetic relationship of avian poxviruses

    USGS Publications Warehouse

    Gyuranecz, Miklós; Foster, Jeffrey T.; Dán, Ádám; Ip, Hon S.; Egstad, Kristina F.; Parker, Patricia G.; Higashiguchi, Jenni M.; Skinner, Michael A.; Höfle, Ursula; Kreizinger, Zsuzsa; Dorrestein, Gerry M.; Solt, Szabolcs; Sós, Endre; Kim, Young Jun; Uhart, Marcela; Pereda, Ariel; González-Hein, Gisela; Hidalgo, Hector; Blanco, Juan-Manuel; Erdélyi, Károly

    2013-01-01

    Poxvirus infections have been found in 230 species of wild and domestic birds worldwide in both terrestrial and marine environments. This ubiquity raises the question of how infection has been transmitted and globally dispersed. We present a comprehensive global phylogeny of 111 novel poxvirus isolates in addition to all available sequences from GenBank. Phylogenetic analysis of Avipoxvirus genus has traditionally relied on one gene region (4b core protein). In this study we have expanded the analyses to include a second locus (DNA polymerase gene), allowing for a more robust phylogenetic framework, finer genetic resolution within specific groups and the detection of potential recombination. Our phylogenetic results reveal several major features of avipoxvirus evolution and ecology and propose an updated avipoxvirus taxonomy, including three novel subclades. The characterization of poxviruses from 57 species of birds in this study extends the current knowledge of their host range and provides the first evidence of the phylogenetic effect of genetic recombination of avipoxviruses. The repeated occurrence of avian family or order-specific grouping within certain clades (e.g. starling poxvirus, falcon poxvirus, raptor poxvirus, etc.) indicates a marked role of host adaptation, while the sharing of poxvirus species within prey-predator systems emphasizes the capacity for cross-species infection and limited host adaptation. Our study provides a broad and comprehensive phylogenetic analysis of the Avipoxvirus genus, an ecologically and environmentally important viral group, to formulate a genome sequencing strategy that will clarify avipoxvirus taxonomy.

  8. HIV-1 vaccines: challenges and new perspectives.

    PubMed

    Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

    2014-01-01

    The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure.

  9. Zoonotic Poxviruses Associated with Companion Animals

    PubMed Central

    Tack, Danielle M.; Reynolds, Mary G.

    2011-01-01

    Simple Summary Contemporary enthusiasm for the ownership of exotic animals and hobby livestock has created an opportunity for the movement of poxviruses—such as monkeypox, cowpox, and orf—outside their traditional geographic range bringing them into contact with atypical animal hosts and groups of people not normally considered at risk. It is important that pet owners and practitioners of human and animal medicine develop a heightened awareness for poxvirus infections and understand the risks that can be associated with companion animals and livestock. This article reviews the epidemiology and clinical features of zoonotic poxviruses that are most likely to affect companion animals. Abstract Understanding the zoonotic risk posed by poxviruses in companion animals is important for protecting both human and animal health. The outbreak of monkeypox in the United States, as well as current reports of cowpox in Europe, point to the fact that companion animals are increasingly serving as sources of poxvirus transmission to people. In addition, the trend among hobbyists to keep livestock (such as goats) in urban and semi-urban areas has contributed to increased parapoxvirus exposures among people not traditionally considered at high risk. Despite the historic notoriety of poxviruses and the diseases they cause, poxvirus infections are often missed. Delays in diagnosing poxvirus-associated infections in companion animals can lead to inadvertent human exposures. Delays in confirming human infections can result in inappropriate treatment or prolonged recovery. Early recognition of poxvirus-associated infections and application of appropriate preventive measures can reduce the spread of virus between companion animals and their owners. This review will discuss the epidemiology and clinical features associated with the zoonotic poxvirus infections most commonly associated with companion animals. PMID:26486622

  10. Primate immune responses to HIV-1 Env formulated in the saponin-based adjuvant AbISCO-100 in the presence or absence of TLR9 co-stimulation

    PubMed Central

    Martinez, Paola; Sundling, Christopher; O'Dell, Sijy; Mascola, John R.; Wyatt, Richard T.; Karlsson Hedestam, Gunilla B.

    2015-01-01

    Protein-based vaccines require adjuvants to achieve optimal responses. Toll-like receptor (TLR) 9 agonists were previously shown to improve responses to protein-based vaccines, such as the Hepatitis B virus vaccine formulated in alum. Here, we used CpG-C together with the clinically relevant saponin-based adjuvant AbISCO-100/Matrix-M (AbISCO), to assess if TLR9 co-stimulation would quantitatively or qualitatively modulate HIV-1 envelope glycoprotein (Env)-specific B and T cell responses in rhesus macaques. The macaques were inoculated with soluble Env trimers in AbISCO, with or without the addition of CpG-C, using an interval similar to the Hepatitis B virus vaccine. Following a comprehensive evaluation of antigen-specific responses in multiple immune compartments, we show that the Env-specific circulating IgG, memory B cells and plasma cells displayed similar kinetics and magnitude in the presence or absence of CpG-C and that there was no apparent difference between the two groups in the elicited HIV-1 neutralizing antibody titers or antigen-specific CD4+ T cell responses. Importantly, the control of SHIV viremia was significantly improved in animals from both Env-immunized groups relative to adjuvant alone controls, demonstrating the potential of AbISCO to act as a stand-alone adjuvant for Env-based vaccines. PMID:25762407

  11. Enteric viruses in HIV-1 seropositive and HIV-1 seronegative children with diarrheal diseases in Brazil

    PubMed Central

    Rocha, Monica Simões; Fumian, Tulio Machado; Maranhão, Adriana Gonçalves; de Assis, Rosane Maria; Xavier, Maria da Penha Trindade Pinheiro; Rocha, Myrna Santos; Miagostovich, Marize Pereira; Leite, José Paulo Gagliardi; Volotão, Eduardo de Mello

    2017-01-01

    Diarrheal diseases (DD) have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different enteric viral agents in HIV-1 seropositive (n = 200) and HIV-1 seronegative (n = 125) children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA), which were detected through enzyme immunoassay, the other enteric viruses (norovirus [NoV], astrovirus [HAstV], adenovirus [HAdV] and bocavirus [HBoV]) were detected through PCR or RT-PCR. A quantitative PCR was performed for RVA, NoV, HAstV, HAdV and HBoV. Infections with NoV (19% vs. 9.6%; p<0.001), HBoV (14% vs. 7.2%; p = 0.042) and HAdV (30.5% vs. 14.4%; p<0.001) were significantly more frequent among HIV-1 seropositive children. RVA was significantly less frequent among HIV-1 seropositive patients (6.5% vs. 20%; p<0.001). Similarly, frequency of infection with HAstV was lower among HIV-1 seropositive children (5.5% vs. 12.8%; p = 0.018). Among HIV-1 seropositive children 33 (16.5%) had co-infections, including three enteric viruses, such as NoV, HBoV and HAdV (n = 2) and NoV, HAstV and HAdV (n = 2). The frequency of infection with more than one virus was 17 (13.6%) in the HIV-1 negative group, triple infection (NoV + HAstV + HBoV) being observed in only one patient. The median viral load of HAstV in feces was significantly higher among HIV-1 positive children compared to HIV-1 negative children. Concerning children infected with RVA, NoV, HBoV and HAdV, no statistically significant differences were observed in the medians of viral loads in feces, comparing HIV-1 seropositive and HIV-1 seronegative children. Similar detection rates were observed for RVA, HAstV and HAdV, whilst NoV and HBoV were significantly more prevalent among children with CD4+ T lymphocyte count below 200 cells/mm3. Enteric viruses should be considered an important cause of DD in HIV-1 seropositive children, along with

  12. Enhanced clearance of HIV-1-infected cells by broadly neutralizing antibodies against HIV-1 in vivo.

    PubMed

    Lu, Ching-Lan; Murakowski, Dariusz K; Bournazos, Stylianos; Schoofs, Till; Sarkar, Debolina; Halper-Stromberg, Ariel; Horwitz, Joshua A; Nogueira, Lilian; Golijanin, Jovana; Gazumyan, Anna; Ravetch, Jeffrey V; Caskey, Marina; Chakraborty, Arup K; Nussenzweig, Michel C

    2016-05-20

    Antiretroviral drugs and antibodies limit HIV-1 infection by interfering with the viral life cycle. In addition, antibodies also have the potential to guide host immune effector cells to kill HIV-1-infected cells. Examination of the kinetics of HIV-1 suppression in infected individuals by passively administered 3BNC117, a broadly neutralizing antibody, suggested that the effects of the antibody are not limited to free viral clearance and blocking new infection but also include acceleration of infected cell clearance. Consistent with these observations, we find that broadly neutralizing antibodies can target CD4(+) T cells infected with patient viruses and can decrease their in vivo half-lives by a mechanism that requires Fcγ receptor engagement in a humanized mouse model. The results indicate that passive immunotherapy can accelerate elimination of HIV-1-infected cells.

  13. HIV-1 imposes rigidity on blood and semen cytokine networks.

    PubMed

    Lisco, Andrea; Introini, Andrea; Munawwar, Arshi; Vanpouille, Christophe; Grivel, Jean-Charles; Blank, Paul; Singh, Sarman; Margolis, Leonid

    2012-12-01

    Although it is established that the levels of individual cytokines are altered by HIV-1 infection, the changes in cytokine interrelations that organize them into networks have been poorly studied. Here, we evaluated these networks in HIV-infected and HIV-uninfected individuals in fluid compartments that are critical for HIV-1 pathogenesis and transmission, namely blood and semen. In samples collected from therapy-naïve HIV-1-infected and HIV-1-uninfected individuals, we measured HIV-1-load, CD4 cell count, and levels of 21 cytokines using a multiplex bead assay. Cytokine networks in blood and semen were different for HIV-1-infected and HIV-1-uninfected individuals. In both compartments of HIV-1-infected individuals, the cytokine networks were more interlocked than in controls: HIV-1 infection resulted in the establishment of new correlations and in the strengthening of pre-existing correlations between different cytokines. In blood and semen of HIV-infected patients, there were, respectively, 68 and 72 statistically significant correlations between cytokines, while in uninfected individuals, there were 18 and 21 such correlations. HIV-1 infection reorganizes the cytokine networks, establishing new strong correlations between various cytokines and thus imposes a high rigidity on the cytokine network. This rigidity may reflect the impairment of the ability of the immune system to respond to microbial challenges. © 2012 John Wiley & Sons A/S.

  14. Chinks in the armor of the HIV-1 Envelope glycan shield: Implications for immune escape from anti-glycan broadly neutralizing antibodies.

    PubMed

    Moyo, Thandeka; Ferreira, Roux-Cil; Davids, Reyaaz; Sonday, Zarinah; Moore, Penny L; Travers, Simon A; Wood, Natasha T; Dorfman, Jeffrey R

    2017-01-15

    Glycans on HIV-1 Envelope serve multiple functions including blocking epitopes from antibodies. We show that removal of glycan 301, a major target of anti-V3/glycan antibodies, has substantially different effects in two viruses. While glycan 301 on Du156.12 blocks epitopes commonly recognized by sera from chronically HIV-1-infected individuals, it does not do so on CAP45.G3, suggesting that removing the 301 glycan has a smaller effect on the integrity of the glycan shield in CAP45.G3. Changes in sensitivity to broadly neutralizing monoclonal antibodies suggest that the interaction between glycan 301 and the CD4 binding site differ substantially between these 2 viruses. Molecular modeling suggests that removal of glycan 301 likely exposes a greater surface area of the V3 and C4 regions in Du156.12. Our data indicate that the contribution of the 301 glycan to resistance to common neutralizing antibodies varies between viruses, allowing for easier selection for its loss in some viruses. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Candida albicans Delays HIV-1 Replication in Macrophages

    PubMed Central

    Rodriguez Rodrigues, Christian; Remes Lenicov, Federico; Jancic, Carolina; Sabatté, Juan; Cabrini, Mercedes; Ceballos, Ana; Merlotti, Antonela; Gonzalez, Heidi; Ostrowski, Matías; Geffner, Jorge

    2013-01-01

    Macrophages are one of the most important HIV-1 target cells. Unlike CD4+ T cells, macrophages are resistant to the cytophatic effect of HIV-1. They are able to produce and harbor the virus for long periods acting as a viral reservoir. Candida albicans (CA) is a commensal fungus that colonizes the portals of HIV-1 entry, such as the vagina and the rectum, and becomes an aggressive pathogen in AIDS patients. In this study, we analyzed the ability of CA to modulate the course of HIV-1 infection in human monocyte-derived macrophages. We found that CA abrogated HIV-1 replication in macrophages when it was evaluated 7 days after virus inoculation. A similar inhibitory effect was observed in monocyte-derived dendritic cells. The analysis of the mechanisms responsible for the inhibition of HIV-1 production in macrophages revealed that CA efficiently sequesters HIV-1 particles avoiding its infectivity. Moreover, by acting on macrophages themselves, CA diminishes their permissibility to HIV-1 infection by reducing the expression of CD4, enhancing the production of the CCR5-interacting chemokines CCL3/MIP-1α, CCL4/MIP-1β, and CCL5/RANTES, and stimulating the production of interferon-α and the restriction factors APOBEC3G, APOBEC3F, and tetherin. Interestingly, abrogation of HIV-1 replication was overcome when the infection of macrophages was evaluated 2-3 weeks after virus inoculation. However, this reactivation of HIV-1 infection could be silenced by CA when added periodically to HIV-1-challenged macrophages. The induction of a silent HIV-1 infection in macrophages at the periphery, where cells are continuously confronted with CA, might help HIV-1 to evade the immune response and to promote resistance to antiretroviral therapy. PMID:24009706

  16. Stress Beyond Translation: Poxviruses and More

    PubMed Central

    Liem, Jason; Liu, Jia

    2016-01-01

    Poxviruses are large double-stranded DNA viruses that form viral factories in the cytoplasm of host cells. These viruses encode their own transcription machinery, but rely on host translation for protein synthesis. Thus, poxviruses have to cope with and, in most cases, reprogram host translation regulation. Granule structures, called antiviral granules (AVGs), have been observed surrounding poxvirus viral factories. AVG formation is associated with abortive poxvirus infection, and AVGs contain proteins that are typically found in stress granules (SGs). With certain mutant poxviruses lack of immunoregulatory factor(s), we can specifically examine the mechanisms that drive the formation of these structures. In fact, cytoplasmic macromolecular complexes form during many viral infections and contain sensing molecules that can help reprogram transcription. More importantly, the similarity between AVGs and cytoplasmic structures formed during RNA and DNA sensing events prompts us to reconsider the cause and consequence of these AVGs. In this review, we first summarize recent findings regarding how poxvirus manipulates host translation. Next, we compare and contrast SGs and AVGs. Finally, we review recent findings regarding RNA- and especially DNA-sensing bodies observed during viral infection. PMID:27314378

  17. Multifarious immunotherapeutic approaches to cure HIV-1 infection.

    PubMed

    Imami, Nesrina; Herasimtschuk, Anna A

    2015-01-01

    Immunotherapy in the context of treated HIV-1 infection aims to improve immune responses to achieve better control of the virus. To date, multifaceted immunotherapeutic approaches have been shown to reduce immune activation and increase CD4 T-lymphocyte counts, further to the effects of antiretroviral therapy alone, in addition to improving HIV-1-specific T-cell responses. While sterilizing cure of HIV-1 would involve elimination of all replication-competent virus, a functional cure in which the host has long-lasting control of viral replication may be more feasible. In this commentary, we discuss novel strategies aimed at targeting the latent viral reservoir with cure of HIV-1 infection being the ultimate goal, an achievement that would have considerable impact on worldwide HIV-1 infection.

  18. Macrophage polarization and HIV-1 infection.

    PubMed

    Cassol, Edana; Cassetta, Luca; Alfano, Massimo; Poli, Guido

    2010-04-01

    Polarization of MP into classically activated (M1) and alternatively activated (M2a, M2b, and M2c) macrophages is critical in mediating an effective immune response against invading pathogens. However, several pathogens use these activation pathways to facilitate dissemination and pathogenesis. Viruses generally induce an M1-like phenotype during the acute phase of infection. In addition to promoting the development of Th1 responses and IFN production, M1 macrophages often produce cytokines that drive viral replication and tissue damage. As shown for HIV-1, polarization can also alter macrophage susceptibility to infection. In vitro polarization into M1 cells prevents HIV-1 infection, and M2a polarization inhibits viral replication at a post-integration level. M2a cells also express high levels of C-type lectins that can facilitate macrophage-mediated transmission of HIV-1 to CD4(+) T cells. Macrophages are particularly abundant in mucosal membranes and unlike DCs, do not usually migrate to distal tissues. As a result, macrophages are likely to contribute to HIV-1 pathogenesis in mucosal rather than lymphatic tissues. In vivo polarization of MP is likely to span a spectrum of activation phenotypes that may change the permissivity to and alter the outcome of HIV-1 and other viral infections.

  19. Cytopathic Mechanisms of HIV-1

    PubMed Central

    Costin, Joshua M

    2007-01-01

    The human immunodeficiency virus type 1 (HIV-1) has been intensely investigated since its discovery in 1983 as the cause of acquired immune deficiency syndrome (AIDS). With relatively few proteins made by the virus, it is able to accomplish many tasks, with each protein serving multiple functions. The Envelope glycoprotein, composed of the two noncovalently linked subunits, SU (surface glycoprotein) and TM (transmembrane glycoprotein) is largely responsible for host cell recognition and entry respectively. While the roles of the N-terminal residues of TM is well established as a fusion pore and anchor for Env into cell membranes, the role of the C-terminus of the protein is not well understood and is fiercely debated. This review gathers information on TM in an attempt to shed some light on the functional regions of this protein. PMID:17945027

  20. Cytopathic mechanisms of HIV-1.

    PubMed

    Costin, Joshua M

    2007-10-18

    The human immunodeficiency virus type 1 (HIV-1) has been intensely investigated since its discovery in 1983 as the cause of acquired immune deficiency syndrome (AIDS). With relatively few proteins made by the virus, it is able to accomplish many tasks, with each protein serving multiple functions. The Envelope glycoprotein, composed of the two noncovalently linked subunits, SU (surface glycoprotein) and TM (transmembrane glycoprotein) is largely responsible for host cell recognition and entry respectively. While the roles of the N-terminal residues of TM is well established as a fusion pore and anchor for Env into cell membranes, the role of the C-terminus of the protein is not well understood and is fiercely debated. This review gathers information on TM in an attempt to shed some light on the functional regions of this protein.

  1. HIV-1 Reverse Transcription

    PubMed Central

    Hu, Wei-Shau; Hughes, Stephen H.

    2012-01-01

    Reverse transcription and integration are the defining features of the Retroviridae; the common name “retrovirus” derives from the fact that these viruses use a virally encoded enzyme, reverse transcriptase (RT), to convert their RNA genomes into DNA. Reverse transcription is an essential step in retroviral replication. This article presents an overview of reverse transcription, briefly describes the structure and function of RT, provides an introduction to some of the cellular and viral factors that can affect reverse transcription, and discusses fidelity and recombination, two processes in which reverse transcription plays an important role. In keeping with the theme of the collection, the emphasis is on HIV-1 and HIV-1 RT. PMID:23028129

  2. Nanochemistry-based immunotherapy for HIV-1.

    PubMed

    Lori, F; Calarota, S A; Lisziewicz, J

    2007-01-01

    Highly active antiretroviral treatment (HAART), i.e. the combination of three or more drugs against human immunodeficiency virus type 1 (HIV-1), has greatly improved the clinical outcome of HIV-1-infected individuals. However, HAART is unable to reconstitute HIV-specific immunity and eradicate the virus. Several observations in primate models and in humans support the notion that cell-mediated immunity can control viral replication and slow disease progression. Thus, besides drugs, an immunotherapy that induces long-lasting HIV-specific T-cell responses could play a role in the treatment of HIV/AIDS. To induce such immune responses, DermaVir Patch has been developed. DermaVir consists of an HIV-1 antigen-encoding plasmid DNA that is chemically formulated in a nanoparticle. DermaVir is administered under a patch after a skin preparation that supports the delivery of the nanoparticle to Langerhans cells (LC). Epidermal LC trap and transport the nanomedicine to draining lymph nodes. While in transit, LC mature into dendritic cells (DC), which can efficiently present the DNA-encoded antigens to naïve T-cells for the induction of cellular immunity. Pre-clinical studies and Phase I clinical testing of DermaVir in HIV-1-infected individuals have demonstrated the safety and tolerability of DermaVir Patch. To further modulate cellular immunity, molecular adjuvants might be added into the nanoparticle. DermaVir Patch represents a new nanomedicine platform for immunotherapy of HIV/AIDS. In this review, the antiviral activity of DermaVir-induced cellular immunity is discussed. Furthermore, the action of some cytokines currently being tested as adjuvants are highlighted and the adjuvant effect of cytokine plasmid DNA included in the DermaVir nanoparticle is reviewed.

  3. The carbohydrate at asparagine 386 on HIV-1 gp120 is not essential for protein folding and function but is involved in immune evasion

    PubMed Central

    Sanders, Rogier W; van Anken, Eelco; Nabatov, Alexei A; Liscaljet, I Marije; Bontjer, Ilja; Eggink, Dirk; Melchers, Mark; Busser, Els; Dankers, Martijn M; Groot, Fedde; Braakman, Ineke; Berkhout, Ben; Paxton, William A

    2008-01-01

    Background The HIV-1 envelope glycoprotein gp120, which mediates viral attachment to target cells, consists for ~50% of sugar, but the role of the individual sugar chains in various aspects of gp120 folding and function is poorly understood. Here we studied the role of the carbohydrate at position 386. We identified a virus variant that had lost the 386 glycan in an evolution study of a mutant virus lacking the disulfide bond at the base of the V4 domain. Results The 386 carbohydrate was not essential for folding of wt gp120. However, its removal improved folding of a gp120 variant lacking the 385–418 disulfide bond, suggesting that it plays an auxiliary role in protein folding in the presence of this disulfide bond. The 386 carbohydrate was not critical for gp120 binding to dendritic cells (DC) and DC-mediated HIV-1 transmission to T cells. In accordance with previous reports, we found that N386 was involved in binding of the mannose-dependent neutralizing antibody 2G12. Interestingly, in the presence of specific substitutions elsewhere in gp120, removal of N386 did not result in abrogation of 2G12 binding, implying that the contribution of N386 is context dependent. Neutralization by soluble CD4 and the neutralizing CD4 binding site (CD4BS) antibody b12 was significantly enhanced in the absence of the 386 sugar, indicating that this glycan protects the CD4BS against antibodies. Conclusion The carbohydrate at position 386 is not essential for protein folding and function, but is involved in the protection of the CD4BS from antibodies. Removal of this sugar in the context of trimeric Env immunogens may therefore improve the elicitation of neutralizing CD4BS antibodies. PMID:18237398

  4. Evaluation of a commercial quail pox vaccine (Bio-Pox Q) for the control of "variant" fowl poxvirus infections.

    PubMed

    Fatunmbi, O O; Reed, W M

    1996-01-01

    Groups of 3-week-old specific pathogen-free chickens immunized with a commercial live-virus quail pox vaccine (Bio-Pox Q) were not protected against challenge with "variant" poxviruses isolated from chickens that were previously vaccinated with commercial fowl pox vaccine. The percentages of vaccinated chickens resistant to challenge with each of the five variant field isolates were 0%, 20%, 0%, 20%, and 10%, respectively. However, when immunity engendered by the variant field isolates was challenged with the commercial quail pox vaccine virus, 80%, 70%, 80%, 50%, and 60% of the vaccinates, respectively, were protected. Results from cross-immunity studies indicate that the commercial quail pox vaccine does share some immunologic relationship with these variant poxvirus field isolates, but not enough to be used in the control of some outbreaks of pox caused by variant poxviruses.

  5. HIV-1 imposes rigidity on blood and semen cytokine networks

    PubMed Central

    LISCO, Andrea; INTROINI, Andrea; MUNAWWAR, Arshi; VANPOUILLE, Christope; GRIVEL, Jean-Charles; BLANK, Paul; SINGH, Sarman

    2012-01-01

    Problem Although it is established that the levels of individual cytokines are altered by HIV-1 infection, the changes in cytokine interrelations that organize them into networks have been poorly studied. Here, we evaluated these networks in HIV-infected and -uninfected individuals in fluid compartments that are critical for HIV-1 pathogenesis and transmission, namely blood and semen. Method of Study In samples collected from therapy-naïve HIV-1-infected and HIV-1-uninfected individuals, we measured HIV-1-load, CD4-cell-count, and levels of 21 cytokines using a multiplex bead-assay. Results Cytokine networks in blood and semen were different for HIV-1-infected and -uninfected individuals. In both compartments of HIV-1-infected individuals, the cytokine networks were more interlocked than in controls: HIV -1 infection results in the establishment of new correlations and the strengthening of pre-existing correlations between different cytokines. In blood and semen of HIV-infected patients there were, respectively, 68 and 72 statistically significant correlations between cytokines, while in uninfected individuals there were 18 and 21 such correlations. Conclusions HIV-1 infection reorganizes the cytokine networks, establishing new strong correlations between various cytokines and thus imposing a high rigidity on the cytokine network. This rigidity may reflect the impairment of the ability of the immune system to respond to microbial challenges. PMID:23006048

  6. Unusual Fusion Proteins of HIV-1

    PubMed Central

    Langer, Simon; Sauter, Daniel

    2017-01-01

    Despite its small genome size, the Human Immunodeficiency Virus 1 (HIV-1) is one of the most successful pathogens and has infected more than 70 million people worldwide within the last decades. In total, HIV-1 expresses 16 canonical proteins from only nine genes within its 10 kb genome. Expression of the structural genes gag, pol, and env, the regulatory genes rev and tat and the accessory genes vpu, nef, vpr, and vif enables assembly of the viral particle, regulates viral gene transcription, and equips the virus to evade or counteract host immune responses. In addition to the canonically expressed proteins, a growing number of publications describe the existence of non-canonical fusion proteins in HIV-1 infected cells. Most of them are encoded by the tat-env-rev locus. While the majority of these fusion proteins (e.g., TNV/p28tev, p186Drev, Tat1-Rev2, Tat^8c, p17tev, or Ref) are the result of alternative splicing events, Tat-T/Vpt is produced upon programmed ribosomal frameshifting, and a Rev1-Vpu fusion protein is expressed due to a nucleotide polymorphism that is unique to certain HIV-1 clade A and C strains. A better understanding of the expression and activity of these non-canonical viral proteins will help to dissect their potential role in viral replication and reveal how HIV-1 optimized the coding potential of its genes. The goal of this review is to provide an overview of previously described HIV-1 fusion proteins and to summarize our current knowledge of their expression patterns and putative functions. PMID:28119676

  7. Forensic Proteomics of Poxvirus Production

    SciTech Connect

    Wunschel, David S.; Tulman, Edan; Engelmann, Heather E.; Clowers, Brian H.; Geary, Steven J.; Robinson, Aaron C.; Liao, Xiaofen

    2013-08-27

    The field of microbial forensics has recently sought to develop methods to discern biological signatures to indicate production methods for biological agents. Viral agents have received less attention to date. Their obligate propagation in living cells makes purification from cellular material a challenge. This leads to potential carryover of protein-rich signature of their production system. Here we have explored a proteomic analysis of Vaccinia virus as a model poxvirus system in which to compare samples of virus propagated in different cell lines and subjected to different purification schemes. The proteomic data sets indicated viral, host cell and culture medium proteins, and several layers of data analysis were applied to build confidence in the peptide identification and capture information on the taxonomic utility of each. The analysis showed clear shifts in protein profiles with virus purification, with successive gradient purification steps showing different levels of viral protein enrichment. Peptides from cellular proteins, including those present in purified virus preparations, provided signatures which enabled discrimination of cell line substrates, including distinguishing between cells derived from different primate species. The ability to discern multiple aspects of viral production demonstrates the potential value of proteomic analysis as tool for microbial forensics.

  8. Therapeutics for HIV-1 reactivation from latency.

    PubMed

    Sgarbanti, Marco; Battistini, Angela

    2013-08-01

    Intensive combined antiretroviral therapy successfully suppresses HIV-1 replication and AIDS disease progression making infection manageable, but it is unable to eradicate the virus that persists in long-lived, drug-insensitive and immune system-insensitive reservoirs thus asking for life-long treatments with problems of compliance, resistance, toxicity and cost. These limitations and recent insights into latency mechanisms have fueled a renewed effort in finding a cure for HIV-1 infection. Proposed eradication strategies involve reactivation of the latent reservoir upon induction of viral transcription followed by the elimination of reactivated virus-producing cells by viral cytopathic effect or host immune response. Several molecules identified by mechanism-directed approaches or in large-scale screenings have been proposed as latency reversing agents. Some of them have already entered clinical testing in humans but with mixed or unsatisfactory results.

  9. Decreased Fc receptor expression on innate immune cells is associated with impaired antibody-mediated cellular phagocytic activity in chronically HIV-1 infected individuals.

    PubMed

    Dugast, Anne-Sophie; Tonelli, Andrew; Berger, Christoph T; Ackerman, Margaret E; Sciaranghella, Gaia; Liu, Qingquan; Sips, Magdalena; Toth, Ildiko; Piechocka-Trocha, Alicja; Ghebremichael, Musie; Alter, Galit

    2011-07-05

    In addition to neutralization, antibodies mediate other antiviral activities including antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular cytotoxicity (ADCC), as well as complement deposition. While it is established that progressive HIV infection is associated with reduced ADCC and ADCP, the underlying mechanism for this loss of function is unknown. Here we report considerable changes in FcR expression over the course of HIV infection on both mDCs and monocytes, including elevated FcγRI expression in acute HIV infection and reduced expression of FcγRII and FcγRIIIa in chronic HIV infection. Furthermore, selective blockade of FcγRII alone was associated with a loss in ADCP activity, suggesting that FcγRII plays a central role in modulating ADCP. Overall, HIV infection is associated with a number of changes in FcR expression on phagocytic cells that are associated with changes in their ability to respond to antibody-opsonized targets, potentially contributing to a failure in viral clearance in progressive HIV-1 infection.

  10. HIV-1 replication.

    PubMed

    Freed, E O

    2001-11-01

    In general terms, the replication cycle of lentiviruses, including HIV-1, closely resembles that of other retroviruses. There are, however, a number of unique aspects of HIV replication; for example, the HIVs and SIVs target receptors and coreceptors distinct from those used by other retroviruses. Lentiviruses encode a number of regulatory and accessory proteins not encoded by the genomes of the prototypical "simple" retroviruses. Of particular interest from the gene therapy perspective, lentiviruses possess the ability to productively infect some types of non-dividing cells. This chapter, while reiterating certain points discussed in Chapter 1, will attempt to focus on issues unique to HIV-1 replication. The HIV-1 genome encodes the major structural and non-structural proteins common to all replication-competent retroviruses (Fig. 1, and Chapter 1). From the 5'- to 3'-ends of the genome are found the gag (for group-specific antigen), pol (for polymerase), and env (for envelope glycoprotein) genes. The gag gene encodes a polyprotein precursor whose name, Pr55Gag, is based on its molecular weight. Pr55Gag is cleaved by the viral protease (PR) to the mature Gag proteins matrix (also known as MA or p17), capsid (CA or p24), nucleocapsid (NC or p7), and p6. Two spacer peptides, p2 and p1, are also generated upon Pr55Gag processing. The pol-encoded enzymes are initially synthesized as part of a large polyprotein precursor, Pr160GagPol, whose synthesis results from a rare frameshifting event during Pr55Gag translation. The individual pol-encoded enzymes, PR, reverse transcriptase (RT), and integrase (IN), are cleaved from Pr160GagPol by the viral PR. The envelope (Env) glycoproteins are also synthesized as a polyprotein precursor (Fig. 1). Unlike the Gag and Pol precursors, which are cleaved by the viral PR, the Env precursor, known as gp160, is processed by a cellular protease during Env trafficking to the cell surface, gp160 processing results in the generation of the

  11. Full-Length HIV-1 Immunogens Induce Greater Magnitude and Comparable Breadth of T Lymphocyte Responses to Conserved HIV-1 Regions Compared with Conserved-Region-Only HIV-1 Immunogens in Rhesus Monkeys

    PubMed Central

    Stephenson, Kathryn E.; SanMiguel, Adam; Simmons, Nathaniel L.; Smith, Kaitlin; Lewis, Mark G.; Szinger, James J.; Korber, Bette

    2012-01-01

    A global HIV-1 vaccine will likely need to induce immune responses against conserved HIV-1 regions to contend with the profound genetic diversity of HIV-1. Here we evaluated the capacity of immunogens consisting of only highly conserved HIV-1 sequences that are aimed at focusing cellular immune responses on these potentially critical regions. We assessed in rhesus monkeys the breadth and magnitude of T lymphocyte responses elicited by adenovirus vectors expressing either full-length HIV-1 Gag/Pol/Env immunogens or concatenated immunogens consisting of only highly conserved HIV-1 sequences. Surprisingly, we found that the full-length immunogens induced comparable breadth (P = 1.0) and greater magnitude (P = 0.01) of CD8+ T lymphocyte responses against conserved HIV-1 regions compared with the conserved-region-only immunogens. Moreover, the full-length immunogens induced a 5-fold increased total breadth of HIV-1-specific T lymphocyte responses compared with the conserved-region-only immunogens (P = 0.007). These results suggest that full-length HIV-1 immunogens elicit a substantially increased magnitude and breadth of cellular immune responses compared with conserved-region-only HIV-1 immunogens, including greater magnitude and comparable breadth of responses against conserved sequences. PMID:22896617

  12. CCR5 Disruption in Induced Pluripotent Stem Cells Using CRISPR/Cas9 Provides Selective Resistance of Immune Cells to CCR5-tropic HIV-1 Virus.

    PubMed

    Kang, HyunJun; Minder, Petra; Park, Mi Ae; Mesquitta, Walatta-Tseyon; Torbett, Bruce E; Slukvin, Igor I

    2015-12-15

    The chemokine (C-C motif) receptor 5 (CCR5) serves as an HIV-1 co-receptor and is essential for cell infection with CCR5-tropic viruses. Loss of functional receptor protects against HIV infection. Here, we report the successful targeting of CCR5 in GFP-marked human induced pluripotent stem cells (iPSCs) using CRISPR/Cas9 with single and dual guide RNAs (gRNAs). Following CRISPER/Cas9-mediated gene editing using a single gRNA, 12.5% of cell colonies demonstrated CCR5 editing, of which 22.2% showed biallelic editing as determined by a Surveyor nuclease assay and direct sequencing. The use of dual gRNAs significantly increased the efficacy of CCR5 editing to 27% with a biallelic gene alteration frequency of 41%. To ensure the homogeneity of gene editing within cells, we used single cell sorting to establish clonal iPSC lines. Single cell-derived iPSC lines with homozygous CCR5 mutations displayed the typical characteristics of pluripotent stem cells and differentiated efficiently into hematopoietic cells, including macrophages. Although macrophages from both wild-type and CCR5-edited iPSCs supported CXCR4-tropic virus replication, macrophages from CCR5-edited iPSCs were uniquely resistant to CCR5-tropic virus challenge. This study demonstrates the feasibility of applying iPSC technology for the study of the role of CCR5 in HIV infection in vitro, and generation of HIV-resistant cells for potential therapeutic applications.

  13. The CSF Immune Response in HIV-1-Associated Cryptococcal Meningitis: Macrophage Activation, Correlates of Disease Severity, and Effect of Antiretroviral Therapy.

    PubMed

    Scriven, James E; Graham, Lisa M; Schutz, Charlotte; Scriba, Thomas J; Wilkinson, Katalin A; Wilkinson, Robert J; Boulware, David R; Urban, Britta C; Meintjes, Graeme; Lalloo, David G

    2017-07-01

    Immune modulation may improve outcome in HIV-associated cryptococcal meningitis. Animal studies suggest alternatively activated macrophages are detrimental but human studies are limited. We performed a detailed assessment of the cerebrospinal fluid (CSF) immune response and examined immune correlates of disease severity and poor outcome, and the effects of antiretroviral therapy (ART). We enrolled persons ≥18 years with first episode of HIV-associated cryptococcal meningitis. CSF immune response was assessed using flow cytometry and multiplex cytokine analysis. Principal component analysis was used to examine relationships between immune response, fungal burden, intracranial pressure and mortality, and the effects of recent ART initiation (<12 weeks). CSF was available from 57 persons (median CD4 34/μL). CD206 (alternatively activated macrophage marker) was expressed on 54% CD14 and 35% CD14 monocyte-macrophages. High fungal burden was not associated with CD206 expression but with a paucity of CD4, CD8, and CD4CD8 T cells and lower interleukin-6, G-CSF, and interleukin-5 concentrations. High intracranial pressure (≥30 cm H2O) was associated with fewer T cells, a higher fungal burden, and larger Cryptococcus organisms. Mortality was associated with reduced interferon-gamma concentrations and CD4CD8 T cells but lost statistical significance when adjusted for multiple comparisons. Recent ART was associated with increased CSF CD4/CD8 ratio and a significantly increased macrophage expression of CD206. Paucity of CSF T cell infiltrate rather than alternative macrophage activation was associated with severe disease in HIV-associated cryptococcosis. ART had a pronounced effect on the immune response at the site of disease.

  14. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

    PubMed Central

    Zhang, Zhiqing; Li, Shaowei; Gu, Ying; Xia, Ningshao

    2016-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection causes acquired immune deficiency syndrome (AIDS), a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART) but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs) with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment. PMID:27869733

  15. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies.

    PubMed

    Zhang, Zhiqing; Li, Shaowei; Gu, Ying; Xia, Ningshao

    2016-11-18

    Human immunodeficiency virus type 1 (HIV-1) infection causes acquired immune deficiency syndrome (AIDS), a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART) but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs) with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  16. Role of IgE immune complexes in the regulation of HIV-1 replication and increased cell death of infected U1 monocytes: involvement of CD23/Fc epsilon RII-mediated nitric oxide and cyclic AMP pathways.

    PubMed Central

    Ouaaz, F.; Ruscetti, F. W.; Dugas, B.; Mikovits, J.; Agut, H.; Debré, P.; Mossalayi, M. D.

    1996-01-01

    BACKGROUND: IgE/anti-IgE immune complexes (IgE-IC) induce the release of multiple mediators from monocytes/macrophages and the monocytic cell line U937 following the ligation of the low-affinity Fc epsilon receptors (Fc epsilon RII/CD23). These effects are mediated through an accumulation of cAMP and the generation of L-arginine-dependent nitric oxide (NO). Since high IgE levels predict more rapid progression to acquired immunodeficiency syndrome, we attempted to define the effects of IgE-IC on human immunodeficiency virus (HIV) production in monocytes. MATERIALS AND METHODS: Two variants of HIV-1 chronically infected monocytic U1 cells were stimulated with IgE-IC and virus replication was quantified. NO and cAMP involvement was tested through the use of agonistic and antagonistic chemicals of these two pathways. RESULTS: IgE-IC induced p24 production by U1 cells with low-level constitutive expression of HIV-1 mRNAs and extracellular HIV capsid protein p24 levels (U1low), upon their pretreatment with interleukin 4 (IL-4) or IL-13. This effect was due to the crosslinking of CD23, as it was reversed by blocking the IgE binding site on CD23. The IgE-IC effect could also be mimicked by crosslinking of CD23 by a specific monoclonal antibody. p24 induction by IgE-IC was then shown to be due to CD23-mediated stimulation of cAMP, NO, and tumor necrosis factor alpha (TNF alpha) generation. In another variant of U1 cells with > 1 log higher constitutive production of p24 levels (U1high), IgE-IC addition dramatically decreased all cell functions tested and accelerated cell death. This phenomenon was reversed by blocking the nitric oxide generation. CONCLUSIONS: These data point out a regulatory role of IgE-IC on HIV-1 production in monocytic cells, through CD23-mediated stimulation of cAMP and NO pathways. IgE-IC can also stimulate increased cell death in high HIV producing cells through the NO pathway. Images FIG. 1 FIG. 2 FIG. 5 PMID:8900533

  17. Eradicating HIV-1 infection: seeking to clear a persistent pathogen

    PubMed Central

    Archin, Nancie M.; Sung, Julia Marsh; Garrido, Carolina; Soriano-Sarabia, Natalia; Margolis, David M.

    2015-01-01

    Effective antiretroviral therapy (ART) blunts viraemia, which enables HIV-1-infected individuals to control infection and live long, productive lives. However, HIV-1 infection remains incurable owing to the persistence of a viral reservoir that harbours integrated provirus within host cellular DNA. This latent infection is unaffected by ART and hidden from the immune system. Recent studies have focused on the development of therapies to disrupt latency. These efforts unmasked residual viral genomes and highlighted the need to enable the clearance of latently infected cells, perhaps via old and new strategies that improve the HIV-1-specific immune response. In this Review, we explore new approaches to eradicate established HIV-1 infection and avoid the burden of lifelong ART. PMID:25402363

  18. An autoreactive antibody from an SLE/HIV-1 individual broadly neutralizes HIV-1

    PubMed Central

    Bonsignori, Mattia; Wiehe, Kevin; Grimm, Sebastian K.; Lynch, Rebecca; Yang, Guang; Kozink, Daniel M.; Perrin, Florence; Cooper, Abby J.; Hwang, Kwan-Ki; Chen, Xi; Liu, Mengfei; McKee, Krisha; Parks, Robert J.; Eudailey, Joshua; Wang, Minyue; Clowse, Megan; Criscione-Schreiber, Lisa G.; Moody, M. Anthony; Ackerman, Margaret E.; Boyd, Scott D.; Gao, Feng; Kelsoe, Garnett; Verkoczy, Laurent; Tomaras, Georgia D.; Liao, Hua-Xin; Kepler, Thomas B.; Montefiori, David C.; Mascola, John R.; Haynes, Barton F.

    2014-01-01

    Broadly HIV-1–neutralizing antibodies (BnAbs) display one or more unusual traits, including a long heavy chain complementarity-determining region 3 (HCDR3), polyreactivity, and high levels of somatic mutations. These shared characteristics suggest that BnAb development might be limited by immune tolerance controls. It has been postulated that HIV-1–infected individuals with autoimmune disease and defective immune tolerance mechanisms may produce BnAbs more readily than those without autoimmune diseases. In this study, we identified an HIV-1–infected individual with SLE who exhibited controlled viral load (<5,000 copies/ml) in the absence of controlling HLA phenotypes and developed plasma HIV-1 neutralization breadth. We collected memory B cells from this individual and isolated a BnAb, CH98, that targets the CD4 binding site (CD4bs) of HIV-1 envelope glycoprotein 120 (gp120). CH98 bound to human antigens including dsDNA, which is specifically associated with SLE. Anti-dsDNA reactivity was also present in the patient’s plasma. CH98 had a mutation frequency of 25% and 15% nt somatic mutations in the heavy and light chain variable domains, respectively, a long HCDR3, and a deletion in the light chain CDR1. The occurrence of anti-dsDNA reactivity by a HIV-1 CD4bs BnAb in an individual with SLE raises the possibility that some BnAbs and SLE-associated autoantibodies arise from similar pools of B cells. PMID:24614107

  19. Clustered epitopes within the Gag-Pol fusion protein DNA vaccine enhance immune responses and protection against challenge with recombinant vaccinia viruses expressing HIV-1 Gag and Pol antigens.

    PubMed

    Bolesta, Elizabeth; Gzyl, Jaroslaw; Wierzbicki, Andrzej; Kmieciak, Dariusz; Kowalczyk, Aleksandra; Kaneko, Yutaro; Srinivasan, Alagarsamy; Kozbor, Danuta

    2005-02-20

    We have generated a codon-optimized hGagp17p24-Polp51 plasmid DNA expressing the human immunodeficiency virus type 1 (HIV-1) Gag-Pol fusion protein that consists of clusters of highly conserved cytotoxic T lymphocyte (CTL) epitopes presented by multiple MHC class I alleles. In the hGagp17p24-Polp51 construct, the ribosomal frameshift site had been deleted together with the potentially immunosuppressive Gag nucleocapsid (p15) as well as Pol protease (p10) and integrase (p31). Analyses of the magnitude and breadth of cellular responses demonstrated that immunization of HLA-A2/K(b) transgenic mice with the hGagp17p24-Polp51 construct induced 2- to 5-fold higher CD8+ T-cell responses to Gag p17-, p24-, and Pol reverse transcriptase (RT)-specific CTL epitopes than the full-length hGag-PolDeltaFsDeltaPr counterpart. The increases were correlated with higher protection against challenge with recombinant vaccinia viruses (rVVs) expressing gag and pol gene products. Consistent with the profile of Gag- and Pol-specific CD8+ T cell responses, an elevated level of type 1 cytokine production was noted in p24- and RT-stimulated splenocyte cultures established from hGagp17p24-Polp51-immunized mice compared to responses induced with the hGag-PolDeltaFsDeltaPr vaccine. Sera of mice immunized with the hGagp17p24-Polp51 vaccine also exhibited an increased titer of p24- and RT-specific IgG2 antibody responses. The results from our studies provide insights into approaches for boosting the breadth of Gag- and Pol-specific immune responses.

  20. HIV-1 Gag p17 presented as virus-like particles on the E2 scaffold from Geobacillus stearothermophilus induces sustained humoral and cellular immune responses in the absence of IFN{gamma} production by CD4+ T cells

    SciTech Connect

    Caivano, Antonella; Doria-Rose, Nicole A.; Buelow, Benjamin; Sartorius, Rossella; Trovato, Maria; D'Apice, Luciana; Domingo, Gonzalo J.; Sutton, William F.; Haigwood, Nancy L.; De Berardinis, Piergiuseppe

    2010-11-25

    We have constructed stable virus-like particles displaying the HIV-1 Gag(p17) protein as an N-terminal fusion with an engineered protein domain from the Geobacillus stearothermophilus pyruvate dehydrogenase subunit E2. Mice immunized with the Gag(p17)-E2 60-mer scaffold particles mounted a strong and sustained antibody response. Antibodies directed to Gag(p17) were boosted significantly with additional immunizations, while anti-E2 responses reached a plateau. The isotype of the induced antibodies was biased towards IgG1, and the E2-primed CD4+ T cells did not secrete IFN{gamma}. Using transgenic mouse model systems, we demonstrated that CD8+ T cells primed with E2 particles were able to exert lytic activity and produce IFN{gamma}. These results show that the E2 scaffold represents a powerful vaccine delivery system for whole antigenic proteins or polyepitope engineered proteins, evoking antibody production and antigen specific CTL activity even in the absence of IFN{gamma}-producing CD4+ T cells.

  1. HIV-1 Gag p17 presented as virus-like particles on the E2 scaffold from Geobacillus stearothermophilus induces sustained humoral and cellular immune responses in the absence of IFNγ production by CD4+ T cells

    PubMed Central

    Caivano, Antonella; Doria-Rose, Nicole A.; Buelow, Benjamin; Sartorius, Rossella; Trovato, Maria; D’Apice, Luciana; Domingo, Gonzalo J.; Sutton, William F.; Haigwood, Nancy L.; De Berardinis, Piergiuseppe

    2012-01-01

    We have constructed stable virus-like particles displaying the HIV-1 Gag(p17) protein as an N-terminal fusion with an engineered protein domain from the Geobacillus stearothermophilus pyruvate dehydrogenase subunit E2. Mice immunized with the Gag(p17)-E2 60-mer scaffold particles mounted a strong and sustained antibody response. Antibodies directed to Gag(p17) were boosted significantly with additional immunizations, while anti-E2 responses reached a plateau. The isotype of the induced antibodies was biased towards IgG1, and the E2-primed CD4+ T cells did not secrete IFNγ. Using transgenic mouse model systems, we demonstrated that CD8+ T cells primed with E2 particles were able to exert lytic activity and produce IFNγ. These results show that the E2 scaffold represents a powerful vaccine delivery system for whole antigenic proteins or polyepitope engineered proteins, evoking antibody production and antigen specific CTL activity even in the absence of IFNγ-producing CD4+ T cells. PMID:20850858

  2. Connectivity and HIV-1 infection: role of CD4(+) T-cell counts and HIV-1 RNA copy number.

    PubMed

    Padierna-Olivos, L; Moreno-Altamirano, M M; Sánchez-Colón, S; Massó-Rojas, F; Sánchez-García, F J

    2000-12-01

    Following primary infection with human immunodeficiency virus (HIV)-1, antibodies against specific HIV-1 epitopes are elicited. However, non-HIV-1 specific antibodies, including autoantibodies, also arise. In fact, it has been proposed that such autoantibodies have an important role in the pathogenesis of HIV-1 infection. Because an imbalance in connectivity has been associated with autoimmune processes, we investigated the connectivity status of HIV-1-infected individuals. Moreover, we tested the possible role of viral load and CD4(+) T-cell counts, in connectivity, because these parameters appear to be important in the prognosis of HIV-1 infection. Results show that indeed, there is an alteration in connectivity in these patients, both for immunoglobulin (Ig)G and IgM, which is an immune alteration not previously identified in HIV-1 infection. In addition, our results show that viral load and CD4(+) T-cell counts are both equally important in defining the characteristic pattern of connectivity in HIV-1-infected individuals, and that neither is independently responsible for alterations in patient connectivity status.

  3. Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

    PubMed

    Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

    2017-10-01

    Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

  4. HIV-1 target cells in the CNS.

    PubMed

    Joseph, Sarah B; Arrildt, Kathryn T; Sturdevant, Christa B; Swanstrom, Ronald

    2015-06-01

    HIV-1 replication in the central nervous system (CNS) is typically limited by the availability of target cells. HIV-1 variants that are transmitted and dominate the early stages of infection almost exclusively use the CCR5 coreceptor and are well adapted to entering, and thus infecting, cells expressing high CD4 densities similar to those found on CD4+ T cells. While the "immune privileged" CNS is largely devoid of CD4+ T cells, macrophage and microglia are abundant throughout the CNS. These cells likely express CD4 densities that are too low to facilitate efficient entry or allow sustained replication by most HIV-1 isolates. Examination of CNS viral populations reveals that late in disease the CNS of some individuals contains HIV-1 lineages that have evolved the ability to enter cells expressing low levels of CD4 and are well-adapted to entering macrophages. These macrophage-tropic (M-tropic) viruses are able to maintain sustained replication in the CNS for many generations, and their presence is associated with severe neurocognitive impairment. Whether conditions such as pleocytosis are necessary for macrophage-tropic viruses to emerge in the CNS is unknown, and extensive examinations of macrophage-tropic variants have not revealed a genetic signature of this phenotype. It is clear, however, that macrophage tropism is rare among HIV-1 isolates and is not transmitted, but is important due to its pathogenic effects on hosts. Prior to the evolution of macrophage-tropic variants, the viruses that are predominately infecting T cells (R5 T cell-tropic) may infect macrophages at a low level and inefficiently, but this could contribute to the reservoir.

  5. HIV-1 target cells in the CNS

    PubMed Central

    Joseph, Sarah B.; Arrildt, Kathryn T.; Sturdevant, Christa B.; Swanstrom, Ronald

    2014-01-01

    HIV-1 replication in the central nervous system (CNS) is typically limited by the availability of target cells. HIV-1 variants that are transmitted and dominate the early stages of infection almost exclusively use the CCR5 coreceptor and are well adapted to entering, and thus infecting, cells expressing high CD4 densities similar to those found on CD4+ T cells. While the “immune privileged” CNS is largely devoid of CD4+ T cells, macrophage and microglia are abundant throughout the CNS. These cells likely express CD4 densities that are too low to facilitate efficient entry or allow sustained replication by most HIV-1 isolates. Examination of CNS viral populations reveals that late in disease the CNS of some individuals contains HIV-1 lineages that have evolved the ability to enter cells expressing low levels of CD4 and are well-adapted to entering macrophages. These macrophage-tropic (M-tropic) viruses are able to maintain sustained replication in the CNS for many generations, and their presence is associated with severe neurocognitive impairment. Whether conditions such as pleocytosis are necessary for macrophage-tropic viruses to emerge in the CNS is unknown, and extensive examinations of macrophage-tropic variants have not revealed a genetic signature of this phenotype. It is clear, however, that macrophage tropism is rare among HIV-1 isolates and is not transmitted, but is important due to its pathogenic effects on hosts. Prior to the evolution of macrophage-tropic variants, the viruses that are predominately infecting T cells (R5 T cell-tropic) may infect macrophages at a low level and inefficiently, but this could contribute to the reservoir. PMID:25236812

  6. Relationship Between Genital Drug Concentrations and Cervical Cellular Immune Activation and Reconstitution in HIV-1-Infected Women on a Raltegravir Versus a Boosted Atazanavir Regimen

    PubMed Central

    Palmer, Claire; Predhomme, Julie; Searls, Kristina; Kerr, Becky; Seifert, Sharon; Caraway, Patricia; Gardner, Edward M.; MaWhinney, Samantha; Anderson, Peter L.

    2015-01-01

    Abstract Determinants of HIV-infected women's genital tract mucosal immune health are not well understood. Because raltegravir (RAL) achieves relatively higher genital tract concentrations than ritonavir-boosted atazanavir (ATV), we examined whether an RAL-based regimen is associated with improved cervical immune reconstitution and less activation in HIV+ women compared to an ATV-based regimen. Peripheral blood, cervical brushings, cervical–vaginal lavage (CVL), and cervical biopsies were collected from HIV+ women on tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) and either RAL (n=14) or ATV (n=19) with CD4+ T cells>300 cells/mm3 and HIV RNA<48 copies/ml. HLA-DR+CD38+ T cells were measured in blood and cervical cells using flow cytometry, CD4+ and CD8+ T cells were quantified in cervical biopsies by immunofluorescent analysis, and HIV RNA (VL), ATV, and RAL concentrations were measured in CVL. In a linear regression model of log(CVL concentration) versus both log(plasma concentration) and treatment group, the RAL CVL level was 519% (95% CI: 133, 1,525%) higher than for ATV (p<0.001). Genital tract VL was undetectable in 90% of subjects and did not differ by regimen. There were no significant differences between groups in terms of cervical %HLA-DR+CD38+CD4+ or CD8+ T cells, CD4+ or CD8+ T cells/mm2, or CD4:CD8 ratio. After adjusting for treatment time and group, the CVL:plasma drug ratio was not associated with the cervical CD4:CD8 ratio or immune activation (p>0.6). Despite significantly higher genital tract penetration of RAL compared to ATV, there were no significant differences in cervical immune activation or reconstitution between women on these regimens, suggesting both drug regimens achieve adequate genital tract levels to suppress virus replication. PMID:26059647

  7. Induction of CD8+ cytotoxic T lymphocytes by immunization with syngeneic irradiated HIV-1 envelope derived peptide-pulsed dendritic cells.

    PubMed

    Takahashi, H; Nakagawa, Y; Yokomuro, K; Berzofsky, J A

    1993-08-01

    Based on the evidence that CD8+ cytotoxic T cells (CTL) precursors do not appear to distinguish between virus-infected cells and viral peptide-pulsed syngeneic cells, we have developed methods for priming class I MHC molecule restricted CD8+ CTL with such peptides without using any adjuvant. We were able to prime in vivo such CTL immunity lasting at least 6 months with a single i.v. injection of syngeneic 2200-3300 rad irradiated peptide-pulsed spleen cells, and even more efficiently with a very small number of irradiated class II MHC molecule expressing splenic dendritic cells (DC). No foreign serum source was necessary during the pulsing. Interestingly, we could not generate significant CTL activity with unirradiated or low dose (< 1100 rad) irradiated spleen cells. Because even purified DC required irradiation for optimal activity, because unirradiated B cells did not significantly inhibit the immunization with DC, and because B cell depletion did not substitute for irradiation, we believe that the effect of irradiation is more to determine homing of the cells than to eliminate interference by B cells. Intravenous immunization was much more effective than s.c. or i.p. immunization. CTL generated by this method could kill both peptide-pulsed syngeneic targets and targets endogenously expressing the whole gp160 gene. Moreover, we found that we could prime CD8+ CTL with the minimal 10-residue core peptide (RGPGRAFVTI) for optimal presentation by class I MHC molecules as efficiently as the original p18. These results suggested that DC bearing antigenic peptide may prime antigen-specific CD8+ CTL in vivo. These results offer useful information for development of synthetic peptide vaccines and immunotherapy.

  8. High-risk oncogenic HPV genotype infection associates with increased immune activation and T cell exhaustion in ART-suppressed HIV-1-infected women

    PubMed Central

    Papasavvas, Emmanouil; Surrey, Lea F.; Glencross, Deborah K.; Azzoni, Livio; Joseph, Jocelin; Omar, Tanvier; Feldman, Michael D.; Williamson, Anna-Lise; Siminya, Maureen; Swarts, Avril; Yin, Xiangfan; Liu, Qin; Firnhaber, Cynthia; Montaner, Luis J.

    2016-01-01

    ABSTRACT Persistence of human papillomavirus (HPV) and cervical disease in the context of HIV co-infection can be influenced by introduction of antiretroviral therapy (ART) and sustained immune activation despite ART. We conducted a cross-sectional study in order to evaluate immune activation/exhaustion in ART-suppressed HIV+ women with or without high-risk (HR) HPV-related cervical intraepithelial neoplasia (CIN). 55 South African women were recruited in three groups: HR (-) (n = 16) and HR (+) (n = 15) HPV with negative cervical histopathology, and HR (+) HPV with CIN grade 1/2/3 (n = 24). Sampling included endocervical brushing (HPV DNA genotyping), Pap smear (cytology), colposcopic punch biopsy (histopathology, histochemical evaluation of immune cells), and peripheral blood (clinical assessment, flow cytometry-based immune subset characterization). Statistics were done using R2.5.1. Irrespective of the presence of CIN, HR (+) HPV women had higher circulating levels of T cells expressing markers of activation/exhaustion (CD38, PD1, CTLA-4, BTLA, CD160), Tregs, and myeloid subsets expressing corresponding ligands (PDL1, PDL2, CD86, CD40, HVEM) than HR (-) HPV women. A decrease in circulating NK cells was associated with CIN grade. CD4+ T cell count associated negatively with T cell exhaustion and expression of negative regulators on myeloid cells. Women with CIN when compared to HR (-) HPV women, had higher cervical cell density in stroma and epithelium for CD4+, CD68+, and CD11c+ cells, and only in stroma for CD8+ cells. We conclude that in ART-suppressed HIV-infected women with HPV co-infection the levels of T and myeloid cell activation/exhaustion are associated with the presence of HR HPV genotypes. PMID:27467943

  9. Induction and Characterization of Immune Responses in Small Animals Using a Venezuelan Equine Encephalitis Virus (VEE) Replicon System, Expressing Human Immunodeficiency Virus Type 1 (HIV-1) Envelope Genes

    DTIC Science & Technology

    2003-01-01

    Montelaro, and C. J. Issel. 1995. Enhanced sensitivity to neutralizing antibodies in a variant of equine infectious anemia virus is linked to amino acid...371-8. 64 36. Davis, N. L., L. V. Willis, J. F. Smith, and R. E. Johnston. 1989. In vitro synthesis of infectious venezuelan equine encephalitis...Characterization of Immune Responses in small animals using a Venezuelan Equine Encephalitis Virus (VEE) Replicon System, Expressing Human

  10. Transplanting Supersites of HIV-1 Vulnerability

    PubMed Central

    Yang, Yongping; Gorman, Jason; Ofek, Gilad; Srivatsan, Sanjay; Druz, Aliaksandr; Lees, Christopher R.; Lu, Gabriel; Soto, Cinque; Stuckey, Jonathan; Burton, Dennis R.; Koff, Wayne C.; Connors, Mark; Kwon, Peter D.

    2014-01-01

    into acceptor scaffolds away from the immune-evading capabilities of the rest of HIV-1 Env, thereby providing a means to focus the immune response on the scaffolded supersite. PMID:24992528

  11. High levels of CC-chemokine expression and downregulated levels of CCR5 during HIV-1/HTLV-1 and HIV-1/HTLV-2 coinfections.

    PubMed

    Oo, Z; Barrios, C S; Castillo, L; Beilke, M A

    2015-05-01

    The human T-cell lymphotropic virus type 1 (HTLV-1) and HTLV-2 are common copathogens among Human Immunodeficiency Virus (HIV)-infected individuals. HTLV-2 may confer a survival benefit among patients with HIV-1/HTLV-2 coinfections, along with lower plasma HIV-1 levels and delayed rates of CD4(+) T-cell decline. These effects have been attributed to the ability of the HTLV-2 viral transactivating Tax2 protein to induce the production of high levels of antiviral CC-chemokines and to downregulate expression of the CCR5 receptor, resulting in impaired entry of HIV-1 into CD4(+) T-cells. This study investigated the innate immunity of coinfected HIV/HTLV individuals by testing the ability of patient PBMCs to produce CC-chemokines in association CCR5 receptor modulation. The cellular proliferative responses of HIV/HTLV coinfected versus HIV monoinfected individuals were also evaluated. Higher levels of MIP-1α, MIP-1β, and RANTES (P < 0.05) were found in HIV-1/HTLV-2 coinfected group compared to HIV-1 monoinfected population. Upregulated levels of RANTES were shown in HIV-1/HTLV-1 after 1 and 3 days of culture (P < 0.05). Lymphocytes from HIV-1/HTLV-2 coinfected individuals showed significant CCR5 downregulation after 1 and 3 days of culture compared to lymphocytes from HIV-1 and uninfected groups (P < 0.05). Lower percentages of CCR5-positive cells were found in HIV-1/HTLV-1 coinfected after 3 days of incubation (P < 0.05). Levels of proliferation were significantly higher in the HIV-1/HTLV-1 group compared to HIV-1 alone (P < 0.05). HTLV-2 and HTLV-1 infections may induce the involvement of innate immunity against HIV-1 via stimulation of CC-chemokines and receptors, potentially modifying CCR5/HIV-1 binding and HIV-1 progression in coinfected individuals.

  12. GB Virus Type C Envelope Protein E2 Elicits Antibodies That React with a Cellular Antigen on HIV-1 Particles and Neutralize Diverse HIV-1 Isolates

    PubMed Central

    Mohr, Emma L.; Xiang, Jinhua; McLinden, James H.; Kaufman, Thomas M.; Chang, Qing; Montefiori, David C.; Klinzman, Donna; Stapleton, Jack T.

    2012-01-01

    Broadly neutralizing Abs to HIV-1 are well described; however, identification of Ags that elicit these Abs has proven difficult. Persistent infection with GB virus type C (GBV-C) is associated with prolonged survival in HIV-1–infected individuals, and among those without HIV-1 viremia, the presence of Ab to GBV-C glycoprotein E2 is also associated with survival. GBV-C E2 protein inhibits HIV-1 entry, and an antigenic peptide within E2 interferes with gp41-induced membrane perturbations in vitro, suggesting the possibility of structural mimicry between GBV-C E2 protein and HIV-1 particles. Naturally occurring human and experimentally induced GBV-C E2 Abs were examined for their ability to neutralize infectious HIV-1 particles and HIV-1–enveloped pseudovirus particles. All GBV-C E2 Abs neutralized diverse isolates of HIV-1 with the exception of rabbit anti-peptide Abs raised against a synthetic GBV-C E2 peptide. Rabbit anti–GBV-C E2 Abs neutralized HIV-1–pseudotyped retrovirus particles but not HIV-1–pseudotyped vesicular stomatitis virus particles, and E2 Abs immune-precipitated HIV-1 gag particles containing the vesicular stomatitis virus type G envelope, HIV-1 envelope, GBV-C envelope, or no viral envelope. The Abs did not neutralize or immune-precipitate mumps or yellow fever viruses. Rabbit GBV-C E2 Abs inhibited HIV attachment to cells but did not inhibit entry following attachment. Taken together, these data indicate that the GBV-C E2 protein has a structural motif that elicits Abs that cross-react with a cellular Ag present on retrovirus particles, independent of HIV-1 envelope glycoproteins. The data provide evidence that a heterologous viral protein can induce HIV-1–neutralizing Abs. PMID:20826757

  13. Post-translational intracellular trafficking determines the type of immune response elicited by DNA vaccines expressing Gag antigen of Human Immunodeficiency Virus Type 1 (HIV-1).

    PubMed

    Wallace, Aaron; West, Kim; Rothman, Alan L; Ennis, Francis A; Lu, Shan; Wang, Shixia

    2013-10-01

    In the current study, immune responses induced by Gag DNA vaccines with different designs were evaluated in Balb/C mice. The results demonstrated that the DNA vaccine with the full length wild type gag gene (Wt-Gag) mainly produced Gag antigens intracellularly and induced a higher level of cell-mediated immune (CMI) responses, as measured by IFN-gamma ELISPOT, intracellular cytokine staining (ICS), and cytotoxic T lymphocytes (CTL) assays against a dominant CD8(+) T cell epitope (AMQMLKETI). In contrast, the addition of a tissue plasminogen activator (tPA) leader sequence significantly improved overall Gag protein expression/secretion and Gag-specific antibody responses; however, Gag-specific CMI responses were decreased. The mutation of zinc-finger motif changed Gag protein expression patterns and reduced the ability to generate both CMI and antibody responses against Gag. These findings indicate that the structure and post-translational processing of antigens expressed by DNA vaccines play a critical role in eliciting optimal antibody or CMI responses.

  14. Post-translational intracellular trafficking determines the type of immune response elicited by DNA vaccines expressing Gag antigen of Human Immunodeficiency Virus Type 1 (HIV-1)

    PubMed Central

    Wallace, Aaron; West, Kim; Rothman, Alan L; Ennis, Francis A; Lu, Shan; Wang, Shixia

    2013-01-01

    In the current study, immune responses induced by Gag DNA vaccines with different designs were evaluated in Balb/C mice. The results demonstrated that the DNA vaccine with the full length wild type gag gene (Wt-Gag) mainly produced Gag antigens intracellularly and induced a higher level of cell-mediated immune (CMI) responses, as measured by IFN-gamma ELISPOT, intracellular cytokine staining (ICS), and cytotoxic T lymphocytes (CTL) assays against a dominant CD8+ T cell epitope (AMQMLKETI). In contrast, the addition of a tissue plasminogen activator (tPA) leader sequence significantly improved overall Gag protein expression/secretion and Gag-specific antibody responses; however, Gag-specific CMI responses were decreased. The mutation of zinc-finger motif changed Gag protein expression patterns and reduced the ability to generate both CMI and antibody responses against Gag. These findings indicate that the structure and post-translational processing of antigens expressed by DNA vaccines play a critical role in eliciting optimal antibody or CMI responses. PMID:23941868

  15. Quantitative Trait Loci for CD4:CD8 Lymphocyte Ratio Are Associated with Risk of Type 1 Diabetes and HIV-1 Immune Control

    PubMed Central

    Ferreira, Manuel A.R.; Mangino, Massimo; Brumme, Chanson J.; Zhao, Zhen Zhen; Medland, Sarah E.; Wright, Margaret J.; Nyholt, Dale R.; Gordon, Scott; Campbell, Megan; McEvoy, Brian P.; Henders, Anjali; Evans, David M.; Lanchbury, Jerry S.; Pereyra, Florencia; Walker, Bruce D.; Haas, David W.; Soranzo, Nicole; Spector, Tim D.; de Bakker, Paul I.W.; Frazer, Ian H.; Montgomery, Grant W.; Martin, Nicholas G.

    2010-01-01

    Abnormal expansion or depletion of particular lymphocyte subsets is associated with clinical manifestations such as HIV progression to AIDS and autoimmune disease. We sought to identify genetic predictors of lymphocyte levels and reasoned that these may play a role in immune-related diseases. We tested 2.3 million variants for association with five lymphocyte subsets, measured in 2538 individuals from the general population, including CD4+ T cells, CD8+ T cells, CD56+ natural killer (NK) cells, and the derived measure CD4:CD8 ratio. We identified two regions of strong association. The first was located in the major histocompatibility complex (MHC), with multiple SNPs strongly associated with CD4:CD8 ratio (rs2524054, p = 2.1 × 10−28). The second region was centered within a cluster of genes from the Schlafen family and was associated with NK cell levels (rs1838149, p = 6.1 × 10−14). The MHC association with CD4:CD8 replicated convincingly (p = 1.4 × 10−9) in an independent panel of 988 individuals. Conditional analyses indicate that there are two major independent quantitative trait loci (QTL) in the MHC region that regulate CD4:CD8 ratio: one is located in the class I cluster and influences CD8 levels, whereas the second is located in the class II cluster and regulates CD4 levels. Jointly, both QTL explained 8% of the variance in CD4:CD8 ratio. The class I variants are also strongly associated with durable host control of HIV, and class II variants are associated with type-1 diabetes, suggesting that genetic variation at the MHC may predispose one to immune-related diseases partly through disregulation of T cell homeostasis. PMID:20045101

  16. Quantitative trait loci for CD4:CD8 lymphocyte ratio are associated with risk of type 1 diabetes and HIV-1 immune control.

    PubMed

    Ferreira, Manuel A R; Mangino, Massimo; Brumme, Chanson J; Zhao, Zhen Zhen; Medland, Sarah E; Wright, Margaret J; Nyholt, Dale R; Gordon, Scott; Campbell, Megan; McEvoy, Brian P; Henders, Anjali; Evans, David M; Lanchbury, Jerry S; Pereyra, Florencia; Walker, Bruce D; Haas, David W; Soranzo, Nicole; Spector, Tim D; de Bakker, Paul I W; Frazer, Ian H; Montgomery, Grant W; Martin, Nicholas G

    2010-01-01

    Abnormal expansion or depletion of particular lymphocyte subsets is associated with clinical manifestations such as HIV progression to AIDS and autoimmune disease. We sought to identify genetic predictors of lymphocyte levels and reasoned that these may play a role in immune-related diseases. We tested 2.3 million variants for association with five lymphocyte subsets, measured in 2538 individuals from the general population, including CD4+ T cells, CD8+ T cells, CD56+ natural killer (NK) cells, and the derived measure CD4:CD8 ratio. We identified two regions of strong association. The first was located in the major histocompatibility complex (MHC), with multiple SNPs strongly associated with CD4:CD8 ratio (rs2524054, p = 2.1 x 10(-28)). The second region was centered within a cluster of genes from the Schlafen family and was associated with NK cell levels (rs1838149, p = 6.1 x 10(-14)). The MHC association with CD4:CD8 replicated convincingly (p = 1.4 x 10(-9)) in an independent panel of 988 individuals. Conditional analyses indicate that there are two major independent quantitative trait loci (QTL) in the MHC region that regulate CD4:CD8 ratio: one is located in the class I cluster and influences CD8 levels, whereas the second is located in the class II cluster and regulates CD4 levels. Jointly, both QTL explained 8% of the variance in CD4:CD8 ratio. The class I variants are also strongly associated with durable host control of HIV, and class II variants are associated with type-1 diabetes, suggesting that genetic variation at the MHC may predispose one to immune-related diseases partly through disregulation of T cell homeostasis.

  17. Association of HIV-1 Envelope-Specific Breast Milk IgA Responses with Reduced Risk of Postnatal Mother-to-Child Transmission of HIV-1

    PubMed Central

    Pollara, Justin; McGuire, Erin; Fouda, Genevieve G.; Rountree, Wes; Eudailey, Josh; Overman, R. Glenn; Seaton, Kelly E.; Deal, Aaron; Edwards, R. Whitney; Tegha, Gerald; Kamwendo, Deborah; Kumwenda, Jacob; Nelson, Julie A. E.; Liao, Hua-Xin; Brinkley, Christie; Denny, Thomas N.; Ochsenbauer, Christina; Ellington, Sascha; King, Caroline C.; Jamieson, Denise J.; van der Horst, Charles; Kourtis, Athena P.; Tomaras, Georgia D.; Ferrari, Guido

    2015-01-01

    ABSTRACT Infants born to HIV-1-infected mothers in resource-limited areas where replacement feeding is unsafe and impractical are repeatedly exposed to HIV-1 throughout breastfeeding. Despite this, the majority of infants do not contract HIV-1 postnatally, even in the absence of maternal antiretroviral therapy. This suggests that immune factors in breast milk of HIV-1-infected mothers help to limit vertical transmission. We compared the HIV-1 envelope-specific breast milk and plasma antibody responses of clade C HIV-1-infected postnatally transmitting and nontransmitting mothers in the control arm of the Malawi-based Breastfeeding Antiretrovirals and Nutrition Study using multivariable logistic regression modeling. We found no association between milk or plasma neutralization activity, antibody-dependent cell-mediated cytotoxicity, or HIV-1 envelope-specific IgG responses and postnatal transmission risk. While the envelope-specific breast milk and plasma IgA responses also did not reach significance in predicting postnatal transmission risk in the primary model after correction for multiple comparisons, subsequent exploratory analysis using two distinct assay methodologies demonstrated that the magnitudes of breast milk total and secretory IgA responses against a consensus HIV-1 envelope gp140 (B.con env03) were associated with reduced postnatal transmission risk. These results suggest a protective role for mucosal HIV-1 envelope-specific IgA responses in the context of postnatal virus transmission. This finding supports further investigations into the mechanisms by which mucosal IgA reduces risk of HIV-1 transmission via breast milk and into immune interventions aimed at enhancing this response. IMPORTANCE Infants born to HIV-1-infected mothers are repeatedly exposed to the virus in breast milk. Remarkably, the transmission rate is low, suggesting that immune factors in the breast milk of HIV-1-infected mothers help to limit transmission. We compared the antibody

  18. Hyperthermia stimulates HIV-1 replication.

    PubMed

    Roesch, Ferdinand; Meziane, Oussama; Kula, Anna; Nisole, Sébastien; Porrot, Françoise; Anderson, Ian; Mammano, Fabrizio; Fassati, Ariberto; Marcello, Alessandro; Benkirane, Monsef; Schwartz, Olivier

    2012-01-01

    HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42-45°C) and Heat Shock Proteins (HSPs) modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38-40°C) on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C) increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity.

  19. Hyperthermia Stimulates HIV-1 Replication

    PubMed Central

    Roesch, Ferdinand; Meziane, Oussama; Kula, Anna; Nisole, Sébastien; Porrot, Françoise; Anderson, Ian; Mammano, Fabrizio; Fassati, Ariberto; Marcello, Alessandro; Benkirane, Monsef; Schwartz, Olivier

    2012-01-01

    HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42–45°C) and Heat Shock Proteins (HSPs) modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38–40°C) on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C) increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity. PMID:22807676

  20. Sex and gender differences in HIV-1 infection.

    PubMed

    Griesbeck, Morgane; Scully, Eileen; Altfeld, Marcus

    2016-08-01

    The major burden of the human immunodeficiency (HIV) type 1 pandemic is nowadays carried by women from sub-Saharan Africa. Differences in the manifestations of HIV-1 infection between women and men have been long reported, and might be due to both socio-economic (gender) and biological (sex) factors. Several studies have shown that women are more susceptible to HIV-1 acquisition than men. Following HIV-1 infection, women have lower viral loads during acute infection and exhibit stronger antiviral responses than men, which may contribute to differences in the size of viral reservoirs. Oestrogen receptor signalling could represent an important mediator of sex differences in HIV-1 reservoir size and may represent a potential therapeutic target. Furthermore, immune activation, a hallmark of HIV-1 infection, is generally higher in women than in men and could be a central mechanism in the sex difference observed in the speed of HIV-1 disease progression. Here, we review the literature regarding sex-based differences in HIV-1 infection and discuss how a better understanding of the underlying mechanisms could improve preventive and therapeutic strategies. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  1. HIV-1 envelope glycoprotein immunogens to induce broadly neutralizing antibodies.

    PubMed

    Sliepen, Kwinten; Sanders, Rogier W

    2016-01-01

    The long pursuit for a vaccine against human immunodeficiency virus 1 (HIV-1) has recently been boosted by a number of exciting developments. An HIV-1 subunit vaccine ideally should elicit potent broadly neutralizing antibodies (bNAbs), but raising bNAbs by vaccination has proved extremely difficult because of the characteristics of the HIV-1 envelope glycoprotein complex (Env). However, the isolation of bNAbs from HIV-1-infected patients demonstrates that the human humoral immune system is capable of making such antibodies. Therefore, a focus of HIV-1 vaccinology is the elicitation of bNAbs by engineered immunogens and by using vaccination strategies aimed at mimicking the bNAb maturation pathways in HIV-infected patients. Important clues can also be taken from the successful subunit vaccines against hepatitis B virus and human papillomavirus. Here, we review the different types of HIV-1 immunogens and vaccination strategies that are being explored in the search for an HIV-1 vaccine that induces bNAbs.

  2. Candidate antibody-based therapeutics against HIV-1.

    PubMed

    Gong, Rui; Chen, Weizao; Dimitrov, Dimiter S

    2012-06-01

    Antibody-based therapeutics have been successfully used for the treatment of various diseases and as research tools. Several well characterized, broadly neutralizing monoclonal antibodies (bnmAbs) targeting HIV-1 envelope glycoproteins or related host cell surface proteins show sterilizing protection of animals, but they are not effective when used for therapy of an established infection in humans. Recently, a number of novel bnmAbs, engineered antibody domains (eAds), and multifunctional fusion proteins have been reported which exhibit exceptionally potent and broad neutralizing activity against a wide range of HIV-1 isolates from diverse genetic subtypes. eAds could be more effective in vivo than conventional full-size antibodies generated by the human immune system. Because of their small size (12∼15 kD), they can better access sterically restricted epitopes and penetrate densely packed tissue where HIV-1 replicates than the larger full-size antibodies. HIV-1 possesses a number of mechanisms to escape neutralization by full-size antibodies but could be less likely to develop resistance to eAds. Here, we review the in vitro and in vivo antiviral efficacies of existing HIV-1 bnmAbs, summarize the development of eAds and multispecific fusion proteins as novel types of HIV-1 inhibitors, and discuss possible strategies to generate more potent antibody-based candidate therapeutics against HIV-1, including some that could be used to eradicate the virus.

  3. The Complex Interaction between Methamphetamine Abuse and HIV-1 pathogenesis

    PubMed Central

    Passaro, Ryan Colby; Pandhare, Jui; Qian, Han-Zhu; Dash, Chandravanu

    2016-01-01

    The global HIV/AIDS pandemic has claimed the lives of an estimated 35 million people. A significant barrier for combating this global pandemic is substance use since it is associated with HIV transmission, delayed diagnosis/initiation of therapy, and poor adherence to therapy. Clinical studies also suggest a link between substance use and HIV-disease progression/AIDS-associated mortality. Methamphetamine (METH) use is one of the fastest-growing substance use problems in the world. METH use enhances high-risk sexual behaviors, therefore increases the likelihood of HIV-1 acquisition. METH use is also associated with higher viral loads, immune dysfunction, and antiretroviral resistance. Moreover, METH use has also been correlated with rapid progression to AIDS. However, direct effects of METH on HIV-1 disease progression remains poorly understood because use of METH and other illicit drugs is often associated with reduced/non adherence to ART. Nevertheless, in vitro studies demonstrate that METH increases HIV-1 replication in cell cultures and animal models. Thus, it has been proposed that METH’s potentiating effects on HIV-1 replication may in part contribute to the worsening of HIV-1 pathogenesis. However, our recent data demonstrate that METH inhibits HIV-1 replication in CD4+ T cells and challenges this paradigm. Thus, the goal of this review is to systematically examine the published literature to better understand the complex interaction between METH abuse and HIV-1 disease progression. PMID:25850893

  4. CD4+ T-cell help enhances NK cell function following therapeutic HIV-1 vaccination.

    PubMed

    Jost, Stephanie; Tomezsko, Phillip John; Rands, Keith; Toth, Ildiko; Lichterfeld, Mathias; Gandhi, Rajesh Tim; Altfeld, Marcus

    2014-08-01

    Increasing data suggest that NK cells can mediate antiviral activity in HIV-1-infected humans, and as such, novel approaches harnessing the anti-HIV-1 function of both T cells and NK cells represent attractive options to improve future HIV-1 immunotherapies. Chronic progressive HIV-1 infection has been associated with a loss of CD4(+) T helper cell function and with the accumulation of anergic NK cells. As several studies have suggested that cytokines produced by CD4(+) T cells are required to enhance NK cell function in various infection models, we hypothesized that reconstitution of HIV-1-specific CD4(+) T-cell responses by therapeutic immunization would restore NK cell activity in infected individuals. Using flow cytometry, we examined the function of CD4(+) T cells and NK cells in response to HIV-1 in subjects with treated chronic HIV-1 infection before and after immunization with an adjuvanted HIV-1 Gp120/NefTat subunit protein vaccine candidate provided by GlaxoSmithKline. Vaccination induced an increased expression of interleukin-2 (IL-2) by Gp120-specific CD4(+) T cells in response to HIV-1 peptides ex vivo, which was associated with enhanced production of gamma interferon (IFN-γ) by NK cells. Our data show that reconstitution of HIV-1-specific CD4(+) T-cell function by therapeutic immunization can enhance NK cell activity in HIV-1-infected individuals. NK cells are effector cells of the innate immune system and are important in the control of viral infection. Recent studies have demonstrated the crucial role played by NK cells in controlling and/or limiting acquisition of HIV-1 infection. However, NK cell function is impaired during progressive HIV-1 infection. We recently showed that therapeutic immunization of treated HIV-1-infected individuals reconstituted strong T-cell responses, measured notably by their production of IL-2, a cytokine that can activate NK cells. The current study suggests that reconstitution of T-cell function by therapeutic

  5. CCL3L1-CCR5 genotype influences durability of immune recovery during antiretroviral therapy of HIV-1–infected individuals

    PubMed Central

    Ahuja, Sunil K; Kulkarni, Hemant; Catano, Gabriel; Agan, Brian K; Camargo, Jose F; He, Weijing; O'Connell, Robert J; Marconi, Vincent C; Delmar, Judith; Eron, Joseph; Clark, Robert A; Frost, Simon; Martin, Jeffrey; Ahuja, Seema S; Deeks, Steven G; Little, Susan; Richman, Douglas; Hecht, Frederick M; Dolan, Matthew J

    2008-01-01

    The basis for the extensive variability seen in the reconstitution of CD4+ T cell counts in HIV-infected individuals receiving highly active antiretroviral therapy (HAART) is not fully known. Here, we show that variations in CCL3L1 gene dose and CCR5 genotype, but not major histocompatibility complex HLA alleles, influence immune reconstitution, especially when HAART is initiated at <350 CD4+ T cells/mm3. The CCL3L1-CCR5 genotypes favoring CD4+ T cell recovery are similar to those that blunted CD4+ T cell depletion during the time before HAART became available (pre-HAART era), suggesting that a common CCL3L1-CCR5 genetic pathway regulates the balance between pathogenic and reparative processes from early in the disease course. Hence, CCL3L1-CCR5 variations influence HIV pathogenesis even in the presence of HAART and, therefore, may prospectively identify subjects in whom earlier initiation of therapy is more likely to mitigate immunologic failure despite viral suppression by HAART. Furthermore, as reconstitution of CD4+ cells during HAART is more sensitive to CCL3L1 dose than to CCR5 genotypes, CCL3L1 analogs might be efficacious in supporting immunological reconstitution. PMID:18376407

  6. Phages and HIV-1: From Display to Interplay

    PubMed Central

    Delhalle, Sylvie; Schmit, Jean-Claude; Chevigné, Andy

    2012-01-01

    The complex hide-and-seek game between HIV-1 and the host immune system has impaired the development of an efficient vaccine. In addition, the high variability of the virus impedes the long-term control of viral replication by small antiviral drugs. For more than 20 years, phage display technology has been intensively used in the field of HIV-1 to explore the epitope landscape recognized by monoclonal and polyclonal HIV-1-specific antibodies, thereby providing precious data about immunodominant and neutralizing epitopes. In parallel, biopanning experiments with various combinatorial or antibody fragment libraries were conducted on viral targets as well as host receptors to identify HIV-1 inhibitors. Besides these applications, phage display technology has been applied to characterize the enzymatic specificity of the HIV-1 protease. Phage particles also represent valuable alternative carriers displaying various HIV-1 antigens to the immune system and eliciting antiviral responses. This review presents and summarizes the different studies conducted with regard to the nature of phage libraries, target display mode and biopanning procedures. PMID:22606007

  7. Viral piracy: HIV-1 targets dendritic cells for transmission.

    PubMed

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.

  8. Tobacco smoking effect on HIV-1 pathogenesis: role of cytochrome P450 isozymes

    PubMed Central

    Ande, Anusha; McArthur, Carole; Kumar, Anil; Kumar, Santosh

    2014-01-01

    Introduction Tobacco smoking is highly prevalent among the HIV-1-infected population. In addition to diminished immune response, smoking has been shown to increase HIV-1 replication and decrease response to antiretroviral therapy, perhaps through drug–drug interaction. However, the mechanism by which tobacco/nicotine increases HIV-1 replication and mediates drug–drug interaction is poorly understood. Areas covered In this review, the authors discuss the effects of smoking on HIV-1 pathogenesis. Since they propose a role for the cytochrome P450 (CYP) pathway in smoking-mediated HIV-1 pathogenesis, the authors briefly converse the role of CYP enzymes in tobacco-mediated oxidative stress and toxicity. Finally, the authors focus on the role of CYP enzymes, especially CYP2A6, in tobacco/nicotine metabolism and oxidative stress in HIV-1 model systems monocytes/macrophages, lymphocytes, astrocytes and neurons, which may be responsible for HIV-1 pathogenesis. Expert opinion Recent findings suggest that CYP-mediated oxidative stress is a novel pathway that may be involved in smoking-mediated HIV-1 pathogenesis, including HIV-1 replication and drug–drug interaction. Thus, CYP and CYP-associated oxidative stress pathways may be potential targets to develop novel pharmaceuticals for HIV-1-infected smokers. Since HIV-1/TB co-infections are common, future study involving interactions between antiretroviral and antituberculosis drugs that involve CYP pathways would also help treat HIV-1/TB co-infected smokers effectively. PMID:23822755

  9. Identification of differentially expressed proteins in the cervical mucosa of HIV-1-resistant sex workers.

    PubMed

    Burgener, Adam; Boutilier, Julie; Wachihi, Charles; Kimani, Joshua; Carpenter, Michael; Westmacott, Garrett; Cheng, Keding; Ball, Terry B; Plummer, Francis

    2008-10-01

    Novel tools are necessary to understand mechanisms of altered susceptibility to HIV-1 infection in women of the Pumwani Sex Worker cohort, Kenya. In this cohort, more than 140 of the 2000 participants have been characterized to be relatively resistant to HIV-1 infection. Given that sexual transmission of HIV-1 occurs through mucosal surfaces such as that in the cervicovaginal environment, our hypothesis is that innate immune factors in the genital tract may play a role in HIV-1 infection resistance. Understanding this mechanism may help develop microbicides and/or vaccines against HIV-1. A quantitative proteomics technique (2D-DIGE: two-dimensional difference in-gel electrophoresis) was used to examine cervical mucosa of HIV-1 resistant women ( n = 10) for biomarkers of HIV-1 resistance. Over 15 proteins were found to be differentially expressed between HIV-1-resistant women and control groups ( n = 29), some which show a greater than 8-fold change. HIV-1-resistant women overexpressed several antiproteases, including those from the serpin B family, and also cystatin A, a known anti-HIV-1 factor. Immunoblotting for a selection of the identified proteins confirmed the DIGE volume differences. Validation of these results on a larger sample of individuals will provide further evidence these biomarkers are associated with HIV-1 resistance and could help aid in the development of effective microbicides against HIV-1.

  10. Towards HIV-1 remission: potential roles for broadly neutralizing antibodies

    PubMed Central

    Halper-Stromberg, Ariel; Nussenzweig, Michel C.

    2016-01-01

    Current antiretroviral drug therapies do not cure HIV-1 because they do not eliminate a pool of long-lived cells harboring immunologically silent but replication-competent proviruses — termed the latent reservoir. Eliminating this reservoir and stimulating the immune response to control infection in the absence of therapy remain important but unsolved goals of HIV-1 cure research. Recently discovered broadly neutralizing antibodies (bNAbs) exhibit remarkable breadth and potency in their ability to neutralize HIV-1 in vitro, and recent studies have demonstrated new therapeutic applications for passively administered bNAbs in vivo. This Review discusses the roles bNAbs might play in HIV-1 treatment regimens, including prevention, therapy, and cure. PMID:26752643

  11. Early Combination Antiretroviral Therapy Limits HIV-1 Persistence in Children.

    PubMed

    Luzuriaga, Katherine

    2016-01-01

    Globally, 240,000 infants are newly infected with HIV-1 each year and 3.2 million children are living with the infection. Combination antiretroviral therapy (cART) has reduced HIV-1-related disease and mortality in children but is not curative owing to the early generation of a latent reservoir of long-lived memory CD4(+) T cells bearing replication-competent HIV-1 provirus integrated into cellular DNA. This review focuses on recent advances in our understanding of the establishment of HIV-1 persistence in children and how early initiation of cART in the setting of the developing infant immune system limits the formation of the long-lived latent CD4(+) cell reservoir that remains a barrier to remission or cure.

  12. Developments in HIV-1 immunotherapy and therapeutic vaccination

    PubMed Central

    Tanner, Helen; Dalgleish, Angus

    2014-01-01

    Since the human immunodeficiency virus (HIV-1) pandemic began, few prophylactic vaccines have reached phase III trials. Only one has shown partial efficacy in preventing HIV-1 infection. The introduction of antiretroviral therapy (ART) has had considerable success in controlling infection and reducing transmission but in so doing has changed the nature of HIV-1 infection for those with access to ART. Access, compliance, and toxicity alongside the emergence of serious non-AIDS morbidity and the sometimes poor immune reconstitution in ART-treated patients have emphasized the need for additional therapies. Such therapy is intended to contribute to control of HIV-1 infection, permit structured treatment interruptions, or even establish a functional cure of permanently suppressed and controlled infection. Both immunotherapy and therapeutic vaccination have the potential to reach these goals. In this review, the latest developments in immunotherapy and therapeutic vaccination are discussed. PMID:24991420

  13. Treating HIV-1 Infection: What Might the Future Hold?

    PubMed Central

    Lichterfeld, Mathias; Zachary, Kimon C.

    2011-01-01

    Advances in antiretroviral combination therapy lasting the past two decades have transformed HIV-1 infection from a fatal disease into a chronic medical condition that in many cases does not compromise life quality. There are 25 different antiretroviral agents available currently, allowing for patient-centered, individualized management of HIV-1 infection, and ongoing progress in HIV-1 virology and antiretroviral pharmacology is likely to expand treatment options further in the future. Nevertheless, antiretroviral therapy continues to have limitations, including insufficient immunological reconstitution, selection of drug resistance, ongoing abnormal immune activation despite effective suppression of HIV-1 viremia, and the inability to target latently infected cells that are responsible for long-term viral persistence. Owing to these shortcomings, the theoretical ability of antiretroviral therapy to extend life expectancy to normal levels is not realized in many cases. Strategies to address these limitations are a matter of active ongoing research and will be summarized in this article. PMID:23251756

  14. Effectiveness, safety, durability and immune recovery in a retrospective, multicentre, observational cohort of ART-experienced, HIV-1-infected patients receiving maraviroc.

    PubMed

    Dentone, C; Sterrantino, G; Signori, A; Cenderello, G; Guerra, M; De Leo, P; Bartolacci, V; Mantia, E; Orofino, G; Giacomini, M; Bruzzone, B; Francisci, D; Di Biagio, A

    2017-10-01

    The aim of this retrospective, multicentre, observational study was to assess the durability, safety, immune recovery and effectiveness on viral suppression of antiretroviral therapy (ART) in a maraviroc (MVC)-based cohort. We collected clinical, demographical, immunological and virological parameters of adult HIV patients who were infected by CCR5-tropic virus and started an ART regimen containing MVC from 2005 to 2012. We created a longitudinal mixed model to assess the change over time of data. We enrolled 126 drug-experienced patients; the median duration of MVC treatment was 25 months. The probability of stopping ART at one year was 13.3%, and at three years was 27.3%. Statistically significant changes were observed for CD4+ cell count increase ( p < 0.001), HIV-RNA decrease ( p < 0.001) and total cholesterol decrease ( p = 0.005). Ninety-four patients (79.7%) had CD4 ≥ 200 cells/mm(3) at baseline while nine of them reached this threshold at nine months (7.6%), 17 (13%) after nine months and six (5%) remained below 200 cells/mm(3) at the end of the study. Overall, 114 patients (90.5%) achieved an HIV-RNA ≤ 50 cp/ml. A majority of patients maintained CD4 cell counts of ≥ 200 cells/mm(3) and achieved an undetectable HIV viral load within three months. MVC-containing regimens are safe and appear to be a feasible therapeutic option for ART.

  15. Specificity and 6-Month Durability of Immune Responses Induced by DNA and Recombinant Modified Vaccinia Ankara Vaccines Expressing HIV-1 Virus-Like Particles

    PubMed Central

    Goepfert, Paul A.; Elizaga, Marnie L.; Seaton, Kelly; Tomaras, Georgia D.; Montefiori, David C.; Sato, Alicia; Hural, John; DeRosa, Stephen C.; Kalams, Spyros A.; McElrath, M. Juliana; Keefer, Michael C.; Baden, Lindsey R.; Lama, Javier R.; Sanchez, Jorge; Mulligan, Mark J.; Buchbinder, Susan P.; Hammer, Scott M.; Koblin, Beryl A.; Pensiero, Michael; Butler, Chris; Moss, Bernard; Robinson, Harriet L.; Donastorg, Yeycy; Qin, Li; Lawrence, Dale; Cardinali, Massimo; Bae, Jin; Holt, Renée; Redinger, Huguette; Johannessen, Jan; Broder, Gail; Moody-White, Jerri; McKay, Butch; Calazans, Gabriela; Bentley, Carter; Kakinami, Lisa; Skibinski, Katie; Estep, Scharla; Tseng, Jenny; Swenson, Molly; Madenwald, Tamra; Overton, Edgar Turner; Edupuganti, Srilatha; Rouphael, Nadine; Whitaker, Jennifer; Hay, C Mhorag; Bunce, Catherine A; Gonzales, Pedro; Hurtado, Juan Carlos; Dolin, Raphael; Mayer, Ken; Walsh, Steven; Johnson, Jennifer

    2014-01-01

    Background. Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)–uninfected adults for safety, immunogenicity, and 6-month durability of immune responses. Methods. A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections. Results. At peak response, 93.2% of the DDMM group and 98.4% of the MMM group had binding antibodies for Env. These binding antibodies were more frequent and of higher magnitude for the transmembrane subunit (gp41) than the receptor-binding subunit (gp120) of Env. For both regimens, response rates were higher for CD4+ T cells (66.4% in the DDMM group and 43.1% in the MMM group) than for CD8+ T cells (21.8% in the DDMM group and 14.9% in the MMM group). Responding CD4+ and CD8+ T cells were biased toward Gag, and >70% produced 2 or 3 of the 4 cytokines evaluated (ie, interferon γ, interleukin 2, tumor necrosis factor α, and granzyme B). Six months after vaccination, the magnitudes of antibodies and T-cell responses had decreased by <3-fold. Conclusions. DDMM and MMM vaccinations with virus-like particle–expressing immunogens elicited durable antibody and T-cell responses. PMID:24403557

  16. Specificity and 6-month durability of immune responses induced by DNA and recombinant modified vaccinia Ankara vaccines expressing HIV-1 virus-like particles.

    PubMed

    Goepfert, Paul A; Elizaga, Marnie L; Seaton, Kelly; Tomaras, Georgia D; Montefiori, David C; Sato, Alicia; Hural, John; DeRosa, Stephen C; Kalams, Spyros A; McElrath, M Juliana; Keefer, Michael C; Baden, Lindsey R; Lama, Javier R; Sanchez, Jorge; Mulligan, Mark J; Buchbinder, Susan P; Hammer, Scott M; Koblin, Beryl A; Pensiero, Michael; Butler, Chris; Moss, Bernard; Robinson, Harriet L

    2014-07-01

    Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)-uninfected adults for safety, immunogenicity, and 6-month durability of immune responses. A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections. At peak response, 93.2% of the DDMM group and 98.4% of the MMM group had binding antibodies for Env. These binding antibodies were more frequent and of higher magnitude for the transmembrane subunit (gp41) than the receptor-binding subunit (gp120) of Env. For both regimens, response rates were higher for CD4(+) T cells (66.4% in the DDMM group and 43.1% in the MMM group) than for CD8(+) T cells (21.8% in the DDMM group and 14.9% in the MMM group). Responding CD4(+) and CD8(+) T cells were biased toward Gag, and >70% produced 2 or 3 of the 4 cytokines evaluated (ie, interferon γ, interleukin 2, tumor necrosis factor α, and granzyme B). Six months after vaccination, the magnitudes of antibodies and T-cell responses had decreased by <3-fold. DDMM and MMM vaccinations with virus-like particle-expressing immunogens elicited durable antibody and T-cell responses. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Syphilis Infection Differentially Regulates the Phenotype and Function of γδ T Cells in HIV-1-Infected Patients Depends on the HIV-1 Disease Stage

    PubMed Central

    Li, Zhen; Lu, Xiaofan; Hu, Zhiliang; Luo, Zhenwu; Jiang, Wei; Wu, Hao; Gao, Yanqing; Yan, Junling; Zhang, Qiuyue; Song, Aixin; Huang, Xiaojie; Mou, Danlei; Su, Bin; Zhang, Tong

    2017-01-01

    A rapidly escalating outbreak of syphilis infection has been affected men who have sex with men, particularly those with HIV-1 infection. γδ T cells are unconventional immune cells with two main subsets, Vδ1 T cells and Vδ2 T cells, which possess a combination of innate and adaptive immune features allowing them against HIV-1. However, whether syphilis infection affects the phenotype and function of γδ T cells in HIV-1-infected patients remains unclear, especially in acute HIV-1 infection (AHI). In this study, we enrolled 57 HIV-1-infected patients (24 with HIV-1 infection only and 33 coinfected with syphilis) from an acute HIV-1-infected cohort in Beijing (PRIMO). A comprehensive analysis of γδ T-cell phenotype and function was performed by flow cytometry. We found syphilis coinfection could reverse the imbalance of Vδ1/Vδ2 ratio in AHI. Syphilis infection results in decreased γδ T-cell activation in AHI, but increased γδ T-cell activation in chronic HIV-1 infection (CHI). Moreover, patients with CHI had larger numbers of IL-17-producing γδ T cells than those with AHI, regardless of syphilis status. Thus, syphilis affected the γδ T-cell immune response differently in patients depending on the stages of HIV-1 disease. In addition, the percentage of IL-17-producing γδ T cells was positively correlated with the percentage of neutrophils. These results suggest that the γδ T-cell/IL-17/neutrophil axis is involved in HIV-1 pathogenesis and disease progression. Taken together, our observations provide new insight into the roles of γδ T cells in immunopathogenesis of syphilis and HIV-1 coinfection, particularly during AHI, and our findings may be helpful for the prevention of syphilis and other sexually transmitted infections and highlight the great significance on the remedy of patients coinfected with HIV-1. PMID:28871259

  18. Stochastic modeling for dynamics of HIV-1 infection using cellular automata: A review.

    PubMed

    Precharattana, Monamorn

    2016-02-01

    Recently, the description of immune response by discrete models has emerged to play an important role to study the problems in the area of human immunodeficiency virus type 1 (HIV-1) infection, leading to AIDS. As infection of target immune cells by HIV-1 mainly takes place in the lymphoid tissue, cellular automata (CA) models thus represent a significant step in understanding when the infected population is dispersed. Motivated by these, the studies of the dynamics of HIV-1 infection using CA in memory have been presented to recognize how CA have been developed for HIV-1 dynamics, which issues have been studied already and which issues still are objectives in future studies.

  19. Evolution of viruses and their impact on human life: HIV-1 subgroup M.

    PubMed

    Becker, Yechiel

    2008-01-01

    The history of mankind over many millennia has been marred by many epidemics caused by viruses which infect the human respiratory system and alimentary tract. The current HIV-1/AIDS pandemic, however, is caused by one virus mutant, HIV-1M, which has evolved to infect humans through the genitals. The virus is able to use the innate system cells of the infected individual to inactivate the adaptive immune system, causing AIDS. The mechanisms used by HIV-1M to inhibit the immune system are presented. Understanding the viral mechanisms is leading to novel antiviral treatments and an approach to an HIV-1 vaccine.

  20. HIV-1 subtypes in Yugoslavia.

    PubMed

    Stanojevic, Maja; Papa, Anna; Papadimitriou, Evagelia; Zerjav, Sonja; Jevtovic, Djordje; Salemovic, Dubravka; Jovanovic, Tanja; Antoniadis, Antonis

    2002-05-01

    To gain insight concerning the genetic diversity of HIV-1 viruses associated with the HIV-1 epidemic in Yugoslavia, 45 specimens from HIV-1-infected individuals were classified into subtypes by sequence-based phylogenetic analysis of the polymerase (pol) region of the viral genome. Forty-one of 45 specimens (91.2%) were identified as pol subtype B, 2 of 45 as subtype C (4.4%), 1 of 45 as CRF01_AE (2.2%), and 1 as CRF02_AG recombinant (2.2%). Nucleotide divergence among subtype B sequences was 4.8%. Results of this study show that among HIV-1-infected patients in Yugoslavia subtype B predominates (91.5%), whereas non-B subtypes are present at a low percentage, mostly related to travel abroad.

  1. Epitope-vaccine strategy against HIV-1: today and tomorrow.

    PubMed

    Liu, Zuqiang; Xiao, Yi; Chen, Ying-Hua

    2003-01-01

    Vaccines play important roles in preventing infectious diseases caused by different pathogens. However, some pathogens such as HIV-1 challenge current vaccine strategy. Poor immunogenicity and the high mutation rate of HIV-1 make great difficulties in inducing potent immune responses strong enough to prevent infection via vaccination. Epitope-vaccine, which could intensively enhance predefined epitope-specific immune responses, was suggested as a new strategy against HIV-1 and HIV-1 mutation. Epitope-vaccines afford powerful approaches to elicit potent, broad and complete immune protection against not only primary homologous viral isolates but also heterologous viral mutants. Although most studies are still preliminary now, epitope-vaccine as a novel strategy against the AIDS epidemic has great developmental potential. To trigger T-cell-dependent IgG antibody responses and improve affinities of the epitope-specific antibodies, approaches such as recombinant multi-epitope-vaccination and prime-boosting vaccination were suggested. Cellular immune responses, especially CTL responses, could also be elicited and enhanced in addition to humoral immune responses. Developed epitope-vaccines activating both arms of the immune system would benefit prevention and immunotherapy not only against HIV but also other chronic infections.

  2. HIV-1 Vpu Does Not Degrade Interferon Regulatory Factor 3

    PubMed Central

    Hotter, Dominik

    2013-01-01

    It has been reported that HIV-1 Vpu mediates the degradation of interferon regulatory factor 3 (IRF-3) to avoid innate immune sensing. Here, we show that Vpu does not deplete IRF-3 from transfected cell lines or HIV-1-infected primary cells. Furthermore, the Vpu-dependent suppression of beta interferon expression described in previous studies could be ascribed to inhibition of NF-κB activation. Thus, Vpu suppresses innate immune activation through inhibition of NF-κB rather than degradation of IRF-3. PMID:23552418

  3. An Integrated Overview of HIV-1 Latency

    PubMed Central

    Ruelas, Debbie S.; Greene, Warner C.

    2015-01-01

    Despite significant advances in our understanding of HIV, a cure has not been realized for the more than 34 million infected with this virus. HIV is incurable because infected individuals harbor cells where the HIV provirus is integrated into the host’s DNA but is not actively replicating and thus is not inhibited by antiviral drugs. Similarly, these latent viruses are not detected by the immune system. In this review, we discuss HIV-1 latency and the mechanisms that allow this pathogenic retrovirus to hide and persist by exploiting the cellular vehicles of immunological memory. PMID:24243012

  4. Enhanced clearance of HIV-1-infected cells by anti-HIV-1 broadly neutralizing antibodies in vivo

    PubMed Central

    Lu, Ching-Lan; Murakowski, Dariusz K.; Bournazos, Stylianos; Schoofs, Till; Sarkar, Debolina; Halper-Stromberg, Ariel; Horwitz, Joshua A.; Nogueira, Lilian; Golijanin, Jovana; Gazumyan, Anna; Ravetch, Jeffrey V.; Caskey, Marina; Chakraborty, Arup K.; Nussenzweig, Michel C.

    2016-01-01

    Anti-retroviral drugs and antibodies limit HIV-1 infection by interfering with the viral life-cycle. In addition, antibodies also have the potential to guide host immune effector cells to kill HIV-1 infected cells. Examination of the kinetics of HIV-1 suppression in infected individuals by passively administered 3BNC117, a broadly neutralizing antibody (bNAb), suggested that the effects of the antibody are not limited to free viral clearance and blocking new infection, but also include acceleration of infected cell clearance. Consistent with these observations, we find that bNAbs can target CD4+ T cells infected with patient viruses and decrease their in vivo half-lives by a mechanism that requires FcγR engagement in a humanized mouse model. The results indicate that passive immunotherapy can accelerate elimination of HIV-1 infected cells. PMID:27199430

  5. HIV-1-Specific T Cell-Dependent Natural Killer (NK) Cell Activation: Major Contribution by NK Cells to Interferon-γ Production in Response to HIV-1 Antigens

    PubMed Central

    Loo, Christopher P.; Long, Brian R.; Hecht, Frederick M.; Nixon, Douglas F.

    2009-01-01

    Abstract Natural killer (NK) cells can directly recognize virus-infected cells. Here, we demonstrate that NK cells also produce interferon (IFN)-γ in an HIV-1-specific, T cell-dependent manner. After stimulation of peripheral blood mononuclear cells (PBMCs) from HIV-1-infected individuals with HIV-1-derived peptides, up to half of the IFN-γ-producing PBMCs are NK cells. These results indicate that T cell-dependent NK cell IFN-γ production can be important for immune control of HIV-1, and have implications for the interpretation of data from vaccine trials using ELISPOT and ELISA. PMID:19500013

  6. Detection of Hepatitis B Virus (HBV) Genomes and HBV Drug Resistant Variants by Deep Sequencing Analysis of HBV Genomes in Immune Cell Subsets of HBV Mono-Infected and/or Human Immunodeficiency Virus Type-1 (HIV-1) and HBV Co-Infected Individuals

    PubMed Central

    Lee, Z.; Nishikawa, S.; Gao, S.; Eksteen, J. B.; Czub, M.; Gill, M. J.; Osiowy, C.; van der Meer, F.; van Marle, G.; Coffin, C. S.

    2015-01-01

    The hepatitis B virus (HBV) and the human immunodeficiency virus type 1 (HIV-1) can infect cells of the lymphatic system. It is unknown whether HIV-1 co-infection impacts infection of peripheral blood mononuclear cell (PBMC) subsets by the HBV. Aims To compare the detection of HBV genomes and HBV sequences in unsorted PBMCs and subsets (i.e., CD4+ T, CD8+ T, CD14+ monocytes, CD19+ B, CD56+ NK cells) in HBV mono-infected vs. HBV/HIV-1 co-infected individuals. Methods Total PBMC and subsets isolated from 14 HBV mono-infected (4/14 before and after anti-HBV therapy) and 6 HBV/HIV-1 co-infected individuals (5/6 consistently on dual active anti-HBV/HIV therapy) were tested for HBV genomes, including replication indicative HBV covalently closed circular (ccc)-DNA, by nested PCR/nucleic hybridization and/or quantitative PCR. In CD4+, and/or CD56+ subsets from two HBV monoinfected cases, the HBV polymerase/overlapping surface region was analyzed by next generation sequencing. Results All analyzed whole PBMC from HBV monoinfected and HBV/HIV coinfected individuals were HBV genome positive. Similarly, HBV DNA was detected in all target PBMC subsets regardless of antiviral therapy, but was absent from the CD4+ T cell subset from all HBV/HIV-1 positive cases (P<0.04). In the CD4+ and CD56+ subset of 2 HBV monoinfected cases on tenofovir therapy, mutations at residues associated with drug resistance and/or immune escape (i.e., G145R) were detected in a minor percentage of the population. Summary HBV genomes and drug resistant variants were detectable in PBMC subsets from HBV mono-infected individuals. The HBV replicates in PBMC subsets of HBV/HIV-1 patients except the CD4+ T cell subpopulation. PMID:26390290

  7. HIV-1 functional cure: will the dream come true?

    PubMed

    Liu, Chao; Ma, Xiancai; Liu, Bingfeng; Chen, Cancan; Zhang, Hui

    2015-11-20

    The reservoir of human immunodeficiency virus type 1 (HIV-1), a long-lived pool of latently infected cells harboring replication-competent viruses, is the major obstacle to curing acquired immune deficiency syndrome (AIDS). Although the combination antiretroviral therapy (cART) can successfully suppress HIV-1 viremia and significantly delay the progression of the disease, it cannot eliminate the viral reservoir and the patient must continue to take anti-viral medicines for life. Currently, the appearance of the 'Berlin patient', the 'Boston patients', and the 'Mississippi baby' have inspired many therapeutic strategies for HIV-1 aimed at curing efforts. However, the specific eradication of viral latency and the recovery and optimization of the HIV-1-specific immune surveillance are major challenges to achieving such a cure. Here, we summarize recent studies addressing the mechanisms underlying the viral latency and define two categories of viral reservoir: 'shallow' and 'deep'. We also present the current strategies and recent advances in the development of a functional cure for HIV-1, focusing on full/partial replacement of the immune system, 'shock and kill', and 'permanent silencing' approaches.

  8. Differential Ability of Primary HIV-1 Nef Isolates To Downregulate HIV-1 Entry Receptors

    PubMed Central

    Toyoda, Mako; Ogata, Yoko; Mahiti, Macdonald; Maeda, Yosuke; Kuang, Xiaomei T.; Miura, Toshiyuki; Jessen, Heiko; Walker, Bruce D.; Brockman, Mark A.; Brumme, Zabrina L.

    2015-01-01

    ABSTRACT HIV-1 Nef downregulates the viral entry receptor CD4 as well as the coreceptors CCR5 and CXCR4 from the surface of HIV-infected cells, and this leads to promotion of viral replication through superinfection resistance and other mechanisms. Nef sequence motifs that modulate these functions have been identified via in vitro mutagenesis with laboratory HIV-1 strains. However, it remains unclear whether the same motifs contribute to Nef activity in patient-derived sequences and whether these motifs may differ in Nef sequences isolated at different infection stages and/or from patients with different disease phenotypes. Here, nef clones from 45 elite controllers (EC), 46 chronic progressors (CP), and 43 acute progressors (AP) were examined for their CD4, CCR5, and CXCR4 downregulation functions. Nef clones from EC exhibited statistically significantly impaired CD4 and CCR5 downregulation ability and modestly impaired CXCR4 downregulation activity compared to those from CP and AP. Nef's ability to downregulate CD4 and CCR5 correlated positively in all cohorts, suggesting that they are functionally linked in vivo. Moreover, impairments in Nef's receptor downregulation functions increased the susceptibility of Nef-expressing cells to HIV-1 infection. Mutagenesis studies on three functionally impaired EC Nef clones revealed that multiple residues, including those at novel sites, were involved in the alteration of Nef functions and steady-state protein levels. Specifically, polymorphisms at highly conserved tryptophan residues (e.g., Trp-57 and Trp-183) and immune escape-associated sites were responsible for reduced Nef functions in these clones. Our results suggest that the functional modulation of primary Nef sequences is mediated by complex polymorphism networks. IMPORTANCE HIV-1 Nef, a key factor for viral pathogenesis, downregulates functionally important molecules from the surface of infected cells, including the viral entry receptor CD4 and coreceptors CCR5

  9. HIV-1: the confounding variables of virus neutralization.

    PubMed

    Nara, Peter L; Lin, George

    2005-06-01

    The development of an effective vaccine against HIV-1 would be greatly facilitated by the ability to elicit potent, high affinity antibodies that are capable of broad neutralization, viral inactivation and protection against infection and/or disease. New insights into the structure and function of the HIV-1 envelope glycoprotein (Env) that mediates viral fusion and entry may ultimately lead to strategies successful in eliciting these protective antibody responses. Insights have been gained regarding HIV-1 Env attachment and receptor engagement, the fusion process and kinetics, and the structural/functional attributes of Env that allow humoral immune evasion. In addition, studies of a limited number of broadly neutralizing human monoclonal antibodies have shed some light as to how antibodies may penetrate the immune evading armor that HIV-1 has evolved. As the elusive goal of generating these types of antibodies emerge and are developed in the context of generating new candidate HIV-1 vaccines, a relevant in vitro measurement of neutralization by these types of antibodies becomes a complex task. This is in part due to a list of confounding variables which include: the physical and genomic nature (amino acid variation) of the infecting virion, the type of target cells, the concentration and clonality of the reactants, assay format and design, the affinity and kinetics of the reaction, receptors/coreceptors and attachment factors, and soluble host factors. This review will focus on the past, current, and future knowledge required to advance the field of HIV-1 humoral immunity as it impacts future HIV-1 vaccine development.

  10. Immunodiffusion Analysis of Yaba Poxvirus Structural and Associated Antigens 1

    PubMed Central

    Olsen, Richard G.; Yohn, David S.

    1970-01-01

    Yaba poxvirus virions were extracted and purified from Rhesus monkey tumors. A saline-soluble virion fraction (Y-xp), obtained by mechanical fractionation of purified virions with an X-press, contained seven components in acrylamide gel electrophoresis; five of these components were reactive in immunodiffusion with whole virion and Y-xp antisera produced in rabbits and monkeys. The saline-insoluble residue remaining after X-press treatment was hydrolyzed with sodium dodecyl sulfate, urea, and 2-mercaptoethanol (SUM). This fraction, Y-sum, contained five components, four of which were demonstrable by immunodiffusion. There was no evidence of antigenic relationships between Y-xp and Y-sum antigens in immunodiffusion. In acrylamide gel electrophoresis, one Y-xp and one Y-sum component had similar mobilities. Y-xp but not Y-sum antisera contained viral-neutralizing antibodies. Virus-free saline extracts of Yaba tumor prepared with Genetron (YS) were essentially devoid of virion structural antigens. They failed to induce precipitating antibodies for virion antigens, were nonreactive in immunodiffusion with virion antisera, and gave low complement-fixation titers with virion antisera. Yaba virion antigens were recovered from the Genetron tumor sediment by SUM and alkaline hydrolysis. Antisera prepared to YS extracts gave a maximum of 17 precipitin lines in immunodiffusion with YS extracts; none was identified as a virion structural antigen. Saline extracts of tumor prepared without Genetron contained immunogenic amounts of 5 virion antigens and 12 to 14 associated antigens. Animals immunized with infected cell culture extracts (virus-free) formed antibodies to six to seven virion antigens. The implications of using extracts of Yaba poxvirus-infected tissues in complement-fixation tests to measure virion antibodies were discussed. Images PMID:4317348

  11. Therapeutic doses of irradiation activate viral transcription and induce apoptosis in HIV-1 infected cells.

    PubMed

    Iordanskiy, Sergey; Van Duyne, Rachel; Sampey, Gavin C; Woodson, Caitlin M; Fry, Kelsi; Saifuddin, Mohammed; Guo, Jia; Wu, Yuntao; Romerio, Fabio; Kashanchi, Fatah

    2015-11-01

    The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4(+) T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4(+) T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4(+) T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the "Shock and Kill" strategy for latently HIV-1 infected cells.

  12. [Mechanisms of resistance to sexual transmission of HIV-1].

    PubMed

    Eberhard, A; Ponceau, B; Biron, F; Verrier, B

    2005-11-01

    Sexual transmission is the most common pathway for HIV-1; nevertheless some individuals remain seronegative despite repeated high risk sexual exposure. These were grouped in cohorts of "highly exposed but persistently seronegative" individuals, mostly prostitutes and flailing couples. Three lines of defence were observed in these cohorts. The first one is the mucosal barrier, the determining factors of which are the type of epithelium (monolayer or multilayer), epithelial integrity, and the pre-existing microflora. The second one is linked to innate immunity directly related to the genetic and/or immune predispositions of the individual: mutations affecting the CCR5 chemokine receptor, secretion of protective soluble factors, and particular HLA alleles. The third one is acquired immunity via the mechanisms of humoral and/or specific cellular immunity. These studies suggest anti HIV-1 vaccinal strategies aiming at a local immunization combining the different types of responses observed in these individuals.

  13. Dendritic Cells and HIV-1 Trans-Infection

    PubMed Central

    McDonald, David

    2010-01-01

    Dendritic cells initiate and sustain immune responses by migrating to sites of pathogenic insult, transporting antigens to lymphoid tissues and signaling immune specific activation of T cells through the formation of the immunological synapse. Dendritic cells can also transfer intact, infectious HIV-1 to CD4 T cells through an analogous structure, the infectious synapse. This replication independent mode of HIV-1 transmission, known as trans-infection, greatly increases T cell infection in vitro and is thought to contribute to viral dissemination in vivo. This review outlines the recent data defining the mechanisms of trans-infection and provides a context for the potential contribution of trans-infection in HIV-1 disease. PMID:21994702

  14. Caveolin-1 mediated uptake via langerin restricts HIV-1 infection in human Langerhans cells.

    PubMed

    van den Berg, Linda M; Ribeiro, Carla M S; Zijlstra-Willems, Esther M; de Witte, Lot; Fluitsma, Donna; Tigchelaar, Wikky; Everts, Vincent; Geijtenbeek, Teunis B H

    2014-12-31

    Human Langerhans cells (LCs) reside in foreskin and vaginal mucosa and are the first immune cells to interact with HIV-1 during sexual transmission. LCs capture HIV-1 through the C-type lectin receptor langerin, which routes the virus into Birbeck granules (BGs), thereby preventing HIV-1 infection. BGs are langerin-positive organelles exclusively present in LCs, however, their origin and function are unknown. Here, we not only show that langerin and caveolin-1 co-localize at the cell membrane and in vesicles but also that BGs are langerin/caveolin-1-positive vesicles are linked to the lysosomal degradation pathway in LCs. Moreover, inhibition of caveolar endocytosis in primary LCs abrogated HIV-1 sequestering into langerin(+) caveolar structures. Notably, both inhibition of caveolar uptake and silencing of caveolar structure protein caveolin-1 resulted in increased HIV-1 integration and subsequent infection. In contrast, inhibition of clathrin-mediated endocytosis did not affect HIV-1 integration, even though HIV-1 uptake was decreased, suggesting that clathrin-mediated endocytosis is not involved in HIV-1 restriction in LCs. Thus, our data strongly indicate that BGs belong to the caveolar endocytosis pathway and that caveolin-1 mediated HIV-1 uptake is an intrinsic restriction mechanism present in human LCs that prevents HIV-1 infection. Harnessing this particular internalization pathway has the potential to facilitate strategies to combat HIV-1 transmission.

  15. Engineering T Cells to Functionally Cure HIV-1 Infection

    PubMed Central

    Leibman, Rachel S; Riley, James L

    2015-01-01

    Despite the ability of antiretroviral therapy to minimize human immunodeficiency virus type 1 (HIV-1) replication and increase the duration and quality of patients' lives, the health consequences and financial burden associated with the lifelong treatment regimen render a permanent cure highly attractive. Although T cells play an important role in controlling virus replication, they are themselves targets of HIV-mediated destruction. Direct genetic manipulation of T cells for adoptive cellular therapies could facilitate a functional cure by generating HIV-1–resistant cells, redirecting HIV-1–specific immune responses, or a combination of the two strategies. In contrast to a vaccine approach, which relies on the production and priming of HIV-1–specific lymphocytes within a patient's own body, adoptive T-cell therapy provides an opportunity to customize the therapeutic T cells prior to administration. However, at present, it is unclear how to best engineer T cells so that sustained control over HIV-1 replication can be achieved in the absence of antiretrovirals. This review focuses on T-cell gene-engineering and gene-editing strategies that have been performed in efforts to inhibit HIV-1 replication and highlights the requirements for a successful gene therapy–mediated functional cure. PMID:25896251

  16. Structured antiretroviral treatment interruptions in chronically HIV-1-infected subjects

    PubMed Central

    Ortiz, Gabriel M.; Wellons, Melissa; Brancato, Jason; Vo, Ha T. T.; Zinn, Rebekah L.; Clarkson, Daniel E.; Van Loon, Katherine; Bonhoeffer, Sebastian; Miralles, G. Diego; Montefiori, David; Bartlett, John A.; Nixon, Douglas F.

    2001-01-01

    The risks and benefits of structured treatment interruption (STI) in HIV-1-infected subjects are not fully understood. A pilot study was performed to compare STI with continuous highly active antiretroviral therapy (HAART) in chronic HIV-1-infected subjects with HIV-1 plasma RNA levels (VL) <400 copies per ml and CD4+ T cells >400 per μl. CD4+ T cells, VL, HIV-1-specific neutralizing antibodies, and IFN-γ-producing HIV-1-specific CD8+ and CD4+ T cells were measured in all subjects. STIs of 1-month duration separated by 1 month of HAART, before a final 3-month STI, resulted in augmented CD8+ T cell responses in all eight STI subjects (P = 0.003), maintained while on HAART up to 22 weeks after STI, and augmented neutralization titers to autologous HIV-1 isolate in one of eight subjects. However, significant decline of CD4+ T cell count from pre-STI level, and VL rebound to pre-HAART baseline, occurred during STI (P = 0.001 and 0.34, respectively). CD4+ T cell counts were regained on return to HAART. Control subjects (n = 4) maintained VL <400 copies per ml and stable CD4+ T cell counts, and showed no enhancement of antiviral CD8+ T cell responses. Despite increases in antiviral immunity, no control of VL was observed. Future studies of STI should proceed with caution. PMID:11687611

  17. Impairment of B-cell functions during HIV-1 infection.

    PubMed

    Amu, Sylvie; Ruffin, Nicolas; Rethi, Bence; Chiodi, Francesca

    2013-09-24

    A variety of B-cell dysfunctions are manifested during HIV-1 infection, as reported early during the HIV-1 epidemic. It is not unusual that the pathogenic mechanisms presented to elucidate impairment of B-cell responses during HIV-1 infection focus on the impact of reduced T-cell numbers and functions, and lack of germinal center formation in lymphoid tissues. To our understanding, however, perturbation of B-cell phenotype and function during HIV-1 infection may begin at several different B-cell developmental stages. These impairments can be mediated by intrinsic B-cell defects as well as by the lack of proper T-cell help. In this review, we will highlight some of the pathways and molecular interactions leading to B-cell impairment prior to germinal center formation and B-cell activation mediated through the B-cell receptor in response to HIV-1 antigens. Recent studies indicate a regulatory role for B cells on T-cell biology and immune responses. We will discuss some of these novel findings and how these regulatory mechanisms could potentially be affected by the intrinsic defects of B cells taking place during HIV-1 infection.

  18. CRISPR-mediated Activation of Latent HIV-1 Expression.

    PubMed

    Limsirichai, Prajit; Gaj, Thomas; Schaffer, David V

    2016-03-01

    Complete eradication of HIV-1 infection is impeded by the existence of cells that harbor chromosomally integrated but transcriptionally inactive provirus. These cells can persist for years without producing viral progeny, rendering them refractory to immune surveillance and antiretroviral therapy and providing a permanent reservoir for the stochastic reactivation and reseeding of HIV-1. Strategies for purging this latent reservoir are thus needed to eradicate infection. Here, we show that engineered transcriptional activation systems based on CRISPR/Cas9 can be harnessed to activate viral gene expression in cell line models of HIV-1 latency. We further demonstrate that complementing Cas9 activators with latency-reversing compounds can enhance latent HIV-1 transcription and that epigenome modulation using CRISPR-based acetyltransferases can also promote viral gene activation. Collectively, these results demonstrate that CRISPR systems are potentially effective tools for inducing latent HIV-1 expression and that their use, in combination with antiretroviral therapy, could lead to improved therapies for HIV-1 infection.

  19. CRISPR-mediated Activation of Latent HIV-1 Expression

    PubMed Central

    Limsirichai, Prajit; Gaj, Thomas; Schaffer, David V

    2016-01-01

    Complete eradication of HIV-1 infection is impeded by the existence of cells that harbor chromosomally integrated but transcriptionally inactive provirus. These cells can persist for years without producing viral progeny, rendering them refractory to immune surveillance and antiretroviral therapy and providing a permanent reservoir for the stochastic reactivation and reseeding of HIV-1. Strategies for purging this latent reservoir are thus needed to eradicate infection. Here, we show that engineered transcriptional activation systems based on CRISPR/Cas9 can be harnessed to activate viral gene expression in cell line models of HIV-1 latency. We further demonstrate that complementing Cas9 activators with latency-reversing compounds can enhance latent HIV-1 transcription and that epigenome modulation using CRISPR-based acetyltransferases can also promote viral gene activation. Collectively, these results demonstrate that CRISPR systems are potentially effective tools for inducing latent HIV-1 expression and that their use, in combination with antiretroviral therapy, could lead to improved therapies for HIV-1 infection. PMID:26607397

  20. HIV-1 increases TLR responses in human primary astrocytes

    PubMed Central

    Serramía, M Jesús; Muñoz-Fernández, M Ángeles; Álvarez, Susana

    2015-01-01

    Astrocytes are the major glial cell within the central nervous system and have a number of important physiological properties related to brain homeostasis. They provide trophic support to neurons and are immune cells with key roles during states-of-inflammation. The potential for production of proinflammatory cytokines and its consequences has been studied in the context of HIV-1 infection of normal human astrocytes (NHA). NHA express TLR3, TLR4, and TLR5. TLR3 ligation induced the strongest proinflammatory polarizing response, characterized by generation of high levels of TNF-α, IL-6, and IL-8. HIV-1 increased the transient production of key inflammatory mediators, and exposure to LPS of HIV-1-infected cells increased significantly the cytokine secretion. We confirmed that it is necessary viral gene expression from the moment of pretreatment with antiretrovirals inhibited totally HIV-1-induced TLR response. The higher response to LPS from HIV-1-infected cells did not correlate with TLR4 or MyD88 increased expression. LPS responsiveness of infected cells parallels MHC class II expression, but not CD14. HIV-1-infected NHA present increased sensitivity to the proinflammatory effects of LPS. If this phenomenon occurs in vivo, it will contribute to the immunopathogenesis of this disease and may ultimately offer novel targets for immunomodulatory therapy. PMID:26671458

  1. Prospects for a globally effective HIV-1 vaccine.

    PubMed

    Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

    2015-11-27

    A globally effective vaccine strategy must cope with the broad genetic diversity of HIV and contend with multiple transmission modalities. Understanding correlates of protection and the role of diversity in limiting protective vaccines with those correlates is key. RV144 was the first HIV-1 vaccine trial to demonstrate efficacy against HIV-1 infection. A correlates analysis compared vaccine-induced immune responses in vaccinated-infected and vaccinated-uninfected volunteers suggested that IgG specific for the V1V2 region of gp120 was associated with reduced risk of HIV-1 infection and that plasma Env IgA was directly correlated with infection risk. RV144 and recent NHP challenge studies suggest that Env is essential and perhaps sufficient to induce protective antibody responses against mucosally acquired HIV-1. Whether RV144 immune correlates can apply to different HIV vaccines, to populations with different modes and intensity of transmission, or to divergent HIV-1 subtypes remains unknown. Newer prime-boost mosaic and conserved sequence immunization strategies aiming at inducing immune responses of greater breadth and depth as well as the development of immunogens inducing broadly neutralizing antibodies should be actively pursued. Efficacy trials are now planned in heterosexual populations in southern Africa and MSM in Thailand. Although NHP challenge studies may guide vaccine development, human efficacy trials remain key to answer the critical questions leading to the development of a global HIV-1 vaccine for licensure. Copyright © 2015 American Journal of Preventive Medicine and Elsevier Ltd. Published by Elsevier Ltd.. All rights reserved.

  2. Genetic identification of novel poxviruses of cetaceans and pinnipeds.

    PubMed

    Bracht, A J; Brudek, R L; Ewing, R Y; Manire, C A; Burek, K A; Rosa, C; Beckmen, K B; Maruniak, J E; Romero, C H

    2006-03-01

    Novel poxviruses were identified in skin lesions of several species of cetaceans and pinnipeds using polymerase chain reaction targeting DNA polymerase and DNA topoisomerase I genes of members of the subfamily Chordopoxvirinae. With the exception of parapoxviruses, no molecular data of marine mammal poxviruses were available to infer genetic and evolutionary relatedness to terrestrial vertebrate poxviruses. Viruses were assigned to a cetacean poxvirus 1 (CPV-1) group based on nucleotide and amino acid identities of gene fragments amplified from skin lesions of Asian bottlenose (Tursiops aduncus), Atlantic bottlenose (Tursiops truncatus), rough-toothed (Steno bredanensis), and striped (Stenella coeruleoalba) dolphins. A different poxvirus was detected in skin lesions of a bowhead whale (Balaena mysticetus) and provisionally assigned to a CPV-2 group. These viruses showed highest identity to terrestrial poxviruses of the genera Orthopoxvirus and Suipoxvirus. A novel species-specific poxvirus was also identified in skin lesions of Steller sea lions (Eumetopias jubatus). None of these poxviruses were found to have amplifiable hemagglutinin gene sequences. Novel parapoxviruses were also identified in skin lesions of Steller sea lions and spotted seals (Phoca largha). A significant degree of divergence was observed in sequences of Steller sea lion parapoxviruses, while those of spotted seals and harbor seals (Phoca vitulina) were highly conserved.

  3. The therapeutic landscape of HIV-1 via genome editing.

    PubMed

    Kwarteng, Alexander; Ahuno, Samuel Terkper; Kwakye-Nuako, Godwin

    2017-07-14

    Current treatment for HIV-1 largely relies on chemotherapy through the administration of antiretroviral drugs. While the search for anti-HIV-1 vaccine remain elusive, the use of highly active antiretroviral therapies (HAART) have been far-reaching and has changed HIV-1 into a manageable chronic infection. There is compelling evidence, including several side-effects of ARTs, suggesting that eradication of HIV-1 cannot depend solely on antiretrovirals. Gene therapy, an expanding treatment strategy, using RNA interference (RNAi) and programmable nucleases such as meganuclease, zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN), and clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins (CRISPR-Cas9) are transforming the therapeutic landscape of HIV-1. TALENS and ZFNS are structurally similar modular systems, which consist of a FokI endonuclease fused to custom-designed effector proteins but have been largely limited, particularly ZFNs, due to their complexity and cost of protein engineering. However, the newly developed CRISPR-Cas9 system, consists of a single guide RNA (sgRNA), which directs a Cas9 endonuclease to complementary target sites, and serves as a superior alternative to the previous protein-based systems. The techniques have been successfully applied to the development of better HIV-1 models, generation of protective mutations in endogenous/host cells, disruption of HIV-1 genomes and even reactivating latent viruses for better detection and clearance by host immune response. Here, we focus on gene editing-based HIV-1 treatment and research in addition to providing  perspectives for refining these techniques.

  4. HIV-1 reservoirs in breast milk and challenges to elimination of breast-feeding transmission of HIV-1.

    PubMed

    Van de Perre, Philippe; Rubbo, Pierre-Alain; Viljoen, Johannes; Nagot, Nicolas; Tylleskär, Thorkild; Lepage, Philippe; Vendrell, Jean-Pierre; Tuaillon, Edouard

    2012-07-18

    By compensating for the relative immaturity of the neonatal immune system, breast milk and breast-feeding prevent deaths in children. Nevertheless, transmission of HIV-1 through breast-feeding is responsible for more than half of new pediatric HIV infections. Recent studies of possible HIV-1 reservoirs in breast milk shed new light on features that influence HIV-1 transmission through breast-feeding. The particular characteristics of breast milk CD4(+) T cells that distinguish them from circulating blood lymphocytes (high frequency of cell activation and expression of memory and mucosal homing markers) facilitate the establishment of HIV-1 replication. Breast milk also contains a plethora of factors with anti-infectious, immunomodulatory, or anti-inflammatory properties that can regulate both viral replication and infant susceptibility. In addition, CD8(+) T lymphocytes, macrophages, and epithelial cells in breast milk can alter the dynamics of HIV-1 transmission. Even during efficient antiretroviral therapy, a residual stable, CD4(+) T cell-associated reservoir of HIV-1 is persistently present in breast milk, a likely source of infection. Only prophylactic treatment in infants--ideally with a long-acting drug, administered for the entire duration of breast-feeding--is likely to protect HIV-exposed babies against all forms of HIV transmission from breast milk, including cell-to-cell viral transfer.

  5. Authentic HIV-1 integrase inhibitors

    PubMed Central

    Liao, Chenzhong; Marchand, Christophe; Burke, Terrence R; Pommier, Yves; Nicklaus, Marc C

    2010-01-01

    HIV-1 integrase (IN) is indispensable for HIV-1 replication and has become a validated target for developing anti-AIDS agents. In two decades of development of IN inhibition-based anti-HIV therapeutics, a significant number of compounds were identified as IN inhibitors, but only some of them showed antiviral activity. This article reviews a number of patented HIV-1 IN inhibitors, especially those that possess high selectivity for the strand transfer reaction. These compounds generally have a polar coplanar moiety, which is assumed to chelate two magnesium ions in the binding site. Resistance to those compounds, when given to patients, can develop as a result of IN mutations. We refer to those compounds as authentic IN inhibitors. Continued drug development has so far delivered one authentic IN inhibitor to the market (raltegravir in 2007). Current and future attention will be focused on the development of novel authentic IN inhibitors with the goal of overcoming viral resistance. PMID:21426159

  6. Preliminary molecular characterization of a fowl poxvirus isolate in Grenada.

    PubMed

    Arathy, D S; Tripathy, D N; Sabarinath, G P; Bhaiyat, M I; Chikweto, A; Matthew, V; Sharma, R N

    2010-09-01

    Two 1-mo-old local breed chickens, with gross lesions in the skin of the head region suspected to be fowl poxvirus infection, were submitted to the Diagnostic Laboratory of the School of Veterinary Medicine, Grenada, West Indies. Cutaneous lesions were collected from these birds for virus isolation, histopathologic diagnosis, and molecular analysis. Fowl poxvirus infection was confirmed by virus isolation in chicken embryo and by histopathology. Molecular characterization of the fowl poxvirus was conducted by PCR amplification of selected genomic fragments and by nucleotide sequencing. Integration of reticuloendotheliosis virus fragments into the fowl poxvirus genome was confirmed by PCR and DNA sequencing. This is the first report from the Caribbean region on the preliminary molecular characterization of a fowl poxvirus isolate.

  7. The macrophage in HIV-1 infection: from activation to deactivation?

    PubMed

    Herbein, Georges; Varin, Audrey

    2010-04-09

    Macrophages play a crucial role in innate and adaptative immunity in response to microorganisms and are an important cellular target during HIV-1 infection. Recently, the heterogeneity of the macrophage population has been highlighted. Classically activated or type 1 macrophages (M1) induced in particular by IFN-gamma display a pro-inflammatory profile. The alternatively activated or type 2 macrophages (M2) induced by Th-2 cytokines, such as IL-4 and IL-13 express anti-inflammatory and tissue repair properties. Finally IL-10 has been described as the prototypic cytokine involved in the deactivation of macrophages (dM). Since the capacity of macrophages to support productive HIV-1 infection is known to be modulated by cytokines, this review shows how modulation of macrophage activation by cytokines impacts the capacity to support productive HIV-1 infection. Based on the activation status of macrophages we propose a model starting with M1 classically activated macrophages with accelerated formation of viral reservoirs in a context of Th1 and proinflammatory cytokines. Then IL-4/IL-13 alternatively activated M2 macrophages will enter into the game that will stop the expansion of the HIV-1 reservoir. Finally IL-10 deactivation of macrophages will lead to immune failure observed at the very late stages of the HIV-1 disease.

  8. Therapeutic doses of irradiation activate viral transcription and induce apoptosis in HIV-1 infected cells

    SciTech Connect

    Iordanskiy, Sergey; Van Duyne, Rachel; Sampey, Gavin C; Woodson, Caitlin M; Fry, Kelsi; Saifuddin, Mohammed; Guo, Jia; Wu, Yuntao; Romerio, Fabio; Kashanchi, Fatah

    2015-11-15

    The highly active antiretroviral therapy reduces HIV-1 RNA in plasma to undetectable levels. However, the virus continues to persist in the long-lived resting CD4{sup +} T cells, macrophages and astrocytes which form a viral reservoir in infected individuals. Reactivation of viral transcription is critical since the host immune response in combination with antiretroviral therapy may eradicate the virus. Using the chronically HIV-1 infected T lymphoblastoid and monocytic cell lines, primary quiescent CD4{sup +} T cells and humanized mice infected with dual-tropic HIV-1 89.6, we examined the effect of various X-ray irradiation (IR) doses (used for HIV-related lymphoma treatment and lower doses) on HIV-1 transcription and viability of infected cells. Treatment of both T cells and monocytes with IR, a well-defined stress signal, led to increase of HIV-1 transcription, as evidenced by the presence of RNA polymerase II and reduction of HDAC1 and methyl transferase SUV39H1 on the HIV-1 promoter. This correlated with the increased GFP signal and elevated level of intracellular HIV-1 RNA in the IR-treated quiescent CD4{sup +} T cells infected with GFP-encoding HIV-1. Exposition of latently HIV-1infected monocytes treated with PKC agonist bryostatin 1 to IR enhanced transcription activation effect of this latency-reversing agent. Increased HIV-1 replication after IR correlated with higher cell death: the level of phosphorylated Ser46 in p53, responsible for apoptosis induction, was markedly higher in the HIV-1 infected cells following IR treatment. Exposure of HIV-1 infected humanized mice with undetectable viral RNA level to IR resulted in a significant increase of HIV-1 RNA in plasma, lung and brain tissues. Collectively, these data point to the use of low to moderate dose of IR alone or in combination with HIV-1 transcription activators as a potential application for the “Shock and Kill” strategy for latently HIV-1 infected cells. - Highlights: • X-ray irradiation

  9. IFITMs: Important Factors In Trans-Mission of HIV-1.

    PubMed

    Sauter, Daniel; Kirchhoff, Frank

    2016-10-12

    IFITMs inhibit various enveloped viral pathogens in vitro, but their relevance in vivo has remained unclear. In this issue of Cell Host & Microbe, Foster et al. (2016) show that IFITMs constitute a barrier to HIV-1 transmission and that escape from adaptive immune responses increases viral sensitivity to IFITM restriction. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. The HIV-1 viral synapse signals human foreskin keratinocytes to secrete thymic stromal lymphopoietin facilitating HIV-1 foreskin entry.

    PubMed

    Zhou, Z; Xu, L; Sennepin, A; Federici, C; Ganor, Y; Tudor, D; Damotte, D; Barry Delongchamps, N; Zerbib, M; Bomsel, M

    2017-04-26

    The complexity of signal transduction resulting from the contact of human immunodeficiency virus type 1 (HIV-1)-infected cells and mucosal cells has hampered our comprehension of HIV-1 mucosal entry. Such process is driven efficiently only by viral synapse contacts, whereas cell-free HIV-1 remains poorly infectious. Using CD4(+) T-cells expressing only HIV-1 envelope inoculated on human adult foreskin tissues, we designed methodologies to identify the signals transduced in foreskin keratinocytes following HIV-1-envelope-dependent viral synapse formation. We find that the viral synapse activates the MyD88-independent TLR-4-nuclear factor (NfκB) signaling pathway in keratinocytes and the subsequent secretion of cytokines including thymic stromal lymphopoietin (TSLP), a cytokine linking innate and T-helper type 2-adaptive immune responses. Moreover, the viral synapse upregulates the non-coding microRNA miR-375, known to control TSLP, and transfection of keratinocytes with anti-miR-375 blocks significantly TSLP secretion. Thus, the secretion of TSLP by keratinocytes is induced by the viral synapse in a miR-375 controlled manner. At the tissue level, these signals translate into the epidermal redistribution of Langerhans cells and formation of conjugates with T-cells, recapitulating the initial events observed in human foreskin infection by HIV-1. These results open new possibilities for designing strategies to block mucosal HIV-1 transmission, the major pathway by which HIV-1 spreads worldwide.Mucosal Immunology advance online publication 26 April 2017; doi:10.1038/mi.2017.23.

  11. Kinetics of human immunodeficiency virus type 1 (HIV-1) DNA and RNA synthesis during primary HIV-1 infection.

    PubMed Central

    Graziosi, C; Pantaleo, G; Butini, L; Demarest, J F; Saag, M S; Shaw, G M; Fauci, A S

    1993-01-01

    HIV-1 replication and viral burden in peripheral blood mononuclear cells (PBMC) have been reported to be high in primary infection but generally very low during the prolonged period of clinical latency. It is uncertain precisely when this transition occurs during the HIV-1 infection and what the relationship is between the changes in HIV-1 replication versus the clearance of infected cells in the overall control of viral replication. In the present study, the kinetics of viral burden (i.e., frequency of HIV-1-infected cells) and replication during primary and early-chronic infection were analyzed in PBMC of four acutely infected individuals. High frequencies of HIV-1-infected cells and high levels of virus replication were observed in PBMC after primary HIV-1 infection. Down-regulation of virus replication in PBMC was observed in all four patients coincident with the emergence of HIV-1-specific immune responses. Other parameters of virus replication, such as circulating plasma p24 antigen and plasma viremia showed similar kinetics. In contrast, a significant decline in viral burden in PBMC was observed in only one of four patients. These results indicate that the down-regulation in the levels of virus replication associated with the clinical transition from acute to chronic infection does not necessarily reflect a reduction in viral burden, thus suggesting the involvement of additional factors. Identification of these factors will be important in elucidating the host mechanisms involved in the early control of HIV-1 infection and disease. Images Fig. 1 Fig. 2 Fig. 3 PMID:8341646

  12. HIV-1 infection induces strong production of IP-10 through TLR7/9-dependent pathways

    PubMed Central

    SIMMONS, Rachel P.; SCULLY, Eileen P.; GRODEN, Erin E.; BENEDICT, Kelly F.; CHANG, J. Judy; LANE, Kim; LIFSON, Jeff; ROSENBERG, Eric; LAUFFENBURGER, Douglas A.; ALTFELD, Marcus

    2014-01-01

    Objective To study the cytokine/chemokine profiles in response to HIV-1 viremia, and elucidate the pathways leading to HIV-1-induced inflammation. Design/Methods Plasma levels of 19 cytokines in individuals with early HIV-1 infection and individuals undergoing treatment interruptions were evaluated via multiplex assay. To investigate the cellular sources of relevant cytokines, sorted cells from HIV-1 infected individuals were assessed for mRNA expression. Relevant signaling pathways were assessed by comparing cytokine production patterns of PBMCs stimulated with intact HIV-1 or specific TLR stimulants with and without a TLR7/9 antagonist. Results IP-10 plasma concentration was most significantly associated with HIV-1 viral load and was the most significant contributor in a multivariate model. IP-10 mRNA was highly expressed in monocytes and mDCs and these cells were the dominant producers after in vitro stimulation with TLR7/8 ligands (CL097 and ssRNAGag1166), AT-2 HIV-1, and HIV-1NL43 virus. Partial least square discriminant analysis of culture supernatants revealed distinct cytokine/chemokine secretion profiles associated with intact viruses compared to TLR7/8 ligands alone, with IP-10 production linked to the former. A TLR7/9 antagonist blocked IP-10 production following whole virus stimulation, suggesting the involvement of TLR7/9 in the recognition of HIV-1 by these cells. Conclusions Monocytes and mDCs produce significant amounts of IP-10 in response to HIV-1 viremia and after in vitro stimulation with HIV-1. Stimulation with HIV-1-derived TLR7/8-ligands versus HIV-1 resulted in distinct cytokine/chemokine profiles, indicating additional pathways other than TLR7/8 that lead to the activation of innate immune cells by HIV-1. PMID:24096630

  13. Nucleic acids encoding mosaic clade M human immunodeficiency virus type 1 (HIV-1) envelope immunogens

    DOEpatents

    Korber, Bette T; Fischer, William; Liao, Hua-Xin; Haynes, Barton F; Letvin, Norman; Hahn, Beatrice H

    2015-04-21

    The present invention relates to nucleic acids encoding mosaic clade M HIV-1 Env polypeptides and to compositions and vectors comprising same. The nucleic acids of the invention are suitable for use in inducing an immune response to HIV-1 in a human.

  14. Antiviral Functions of Human Immunodeficiency Virus Type 1 (HIV-1)-Specific IgG Antibodies: Effects of Antiretroviral Therapy and Implications for Therapeutic HIV-1 Vaccine Design

    PubMed Central

    French, Martyn A.; Tjiam, M. Christian; Abudulai, Laila N.; Fernandez, Sonia

    2017-01-01

    Contemporary antiretroviral therapy (ART) is effective and tolerable for long periods of time but cannot eradicate human immunodeficiency virus type 1 (HIV-1) infection by either elimination of viral reservoirs or enhancement of HIV-1-specific immune responses. Boosting “protective” HIV-1-specific immune responses by active or passive immunization will therefore be necessary to control or eradicate HIV-1 infection and is currently the topic of intense investigation. Recently reported studies conducted in HIV patients and non-human primate (NHP) models of HIV-1 infection suggest that HIV-1-specific IgG antibody responses may contribute to the control of HIV-1 infection. However, production of IgG antibodies with virus neutralizing activity by vaccination remains problematic and while vaccine-induced natural killer cell-activating IgG antibodies have been shown to prevent the acquisition of HIV-1 infection, they may not be sufficient to control or eradicate established HIV-1 infection. It is, therefore, important to consider other functional characteristics of IgG antibody responses. IgG antibodies to viruses also mediate opsonophagocytic antibody responses against virions and capsids that enhance the function of phagocytic cells playing critical roles in antiviral immune responses, particularly conventional dendritic cells and plasmacytoid dendritic cells. Emerging evidence suggests that these antibody functions might contribute to the control of HIV-1 infection. In addition, IgG antibodies contribute to the intracellular degradation of viruses via binding to the cytosolic fragment crystallizable (Fc) receptor tripartite motif containing-21 (TRIM21). The functional activity of an IgG antibody response is influenced by the IgG subclass content, which affects binding to antigens and to Fcγ receptors on phagocytic cells and to TRIM21. The IgG subclass content and avidity of IgG antibodies is determined by germinal center (GC) reactions in follicles of lymphoid

  15. Characterization of Deoxyribonucleases Induced by Poxviruses 1

    PubMed Central

    Jungwirth, C.; Launer, J.; Dombrowski, G.; Horák, I.

    1969-01-01

    Increases in deoxyribonuclease activity assayed at alkaline pH can be observed in poxvirus-infected cells when native or denatured deoxyribonucleic acid (DNA) is used as substrate. The deoxyribonuclease assayable with native DNA as substrate, induced in HeLa cells by cowpoxvirus or vaccinia virus WR, can be separated from the corresponding enzyme present in normal cells by chromatography on diethylaminoethyl cellulose. In addition, the two enzymes induced in the virus-infected cells differ from each other in their chromatographic properties. The two induced enzymes have been further characterized with respect to properties of enzymatic reaction. PMID:16789119

  16. Broad HIV-1 inhibition in vitro by vaccine-elicited CD8+ T cells in African adults

    PubMed Central

    Mutua, Gaudensia; Farah, Bashir; Langat, Robert; Indangasi, Jackton; Ogola, Simon; Onsembe, Brian; Kopycinski, Jakub T; Hayes, Peter; Borthwick, Nicola J; Ashraf, Ambreen; Dally, Len; Barin, Burc; Tillander, Annika; Gilmour, Jill; De Bont, Jan; Crook, Alison; Hannaman, Drew; Cox, Josephine H; Anzala, Omu; Fast, Patricia E; Reilly, Marie; Chinyenze, Kundai; Jaoko, Walter; Hanke, Tomáš; HIV-CORE 004 study group, the

    2016-01-01

    We are developing a pan-clade HIV-1 T-cell vaccine HIVconsv, which could complement Env vaccines for prophylaxis and be a key to HIV cure. Our strategy focuses vaccine-elicited effector T-cells on functionally and structurally conserved regions (not full-length proteins and not only epitopes) of the HIV-1 proteome, which are common to most global variants and which, if mutated, cause a replicative fitness loss. Our first clinical trial in low risk HIV-1-negative adults in Oxford demonstrated the principle that naturally mostly subdominant epitopes, when taken out of the context of full-length proteins/virus and delivered by potent regimens involving combinations of simian adenovirus and poxvirus modified vaccinia virus Ankara, can induce robust CD8+ T cells of broad specificities and functions capable of inhibiting in vitro HIV-1 replication. Here and for the first time, we tested this strategy in low risk HIV-1-negative adults in Africa. We showed that the vaccines were well tolerated and induced high frequencies of broadly HIVconsv-specific plurifunctional T cells, which inhibited in vitro viruses from four major clades A, B, C, and D. Because sub-Saharan Africa is globally the region most affected by HIV-1/AIDS, trial HIV-CORE 004 represents an important stage in the path toward efficacy evaluation of this highly rational and promising vaccine strategy. PMID:27617268

  17. The changes in the T helper 1 (Th1) and T helper 2 (Th2) cytokine balance during HIV-1 infection are indicative of an allergic response to viral proteins that may be reversed by Th2 cytokine inhibitors and immune response modifiers--a review and hypothesis.

    PubMed

    Becker, Yechiel

    2004-01-01

    The HIV-1 infection in humans induces an early cellular immune response to react to the viral proteins with a cytotoxic T cell (CTL) response that fails to inhibit virus replication and the spread of the virus. It became evident that the progression of the disease causes chronic changes to the immune system of which a gradual increase in IgE antibodies is one of its features. When the HIV-1 epidemic began, the relation between the gradual increase in IgE content and AIDS was not understood, but later it became a marker for disease prognosis. The advances in the knowledge on T helper 1 (Th1) and T helper 2 (Th2) cells revealed that Th1 cells produce cytokines that stimulate the proliferation of CTLs. Th2 cells produce cytokines that are responsible for the activation of the humoral immune response in healthy people. Studies on both Th1 and Th2 cytokine synthesis revealed an aberration in HIV-1 infected people. Clerici and Shearer presented a hypothesis (1993) whereby Th1 cell activity declines and Th2 activity increases (the Th1 --> Th2 switch hypothesis) in HIV-1 infected people. In fact, experiments concerning this hypothesis ultimately supported the premise that the switch involves a critical change in the cytokine balance, which leads to the contraction of AIDS. However, the research community must still discern why such a Th1 --> Th2 switch takes place in infected people and how it can be reversed. The present review points to the fact that a similar Th1 --> Th2 switch constitutes the response of allergic people to environmental allergens. HIV-1 patients and allergic people that are exposed to allergens respond with an increased synthesis of Th2 cytokines and IgE, together with a decrease in Th1 cytokines. The studies on allergen-induced Th2 cells revealed that the Th2 cytokine IL-4 induces B cells to synthesize IgE, and cytokine IL-5 is the inducer of eosinophilia, just as in HIV-1 infection. The difference between the HIV-1 infection and allergies is the

  18. Mother-to-Child HIV-1 Transmission Events Are Differentially Impacted by Breast Milk and Its Components from HIV-1-Infected Women.

    PubMed

    Shen, Ruizhong; Achenbach, Jenna; Shen, Yue; Palaia, Jana; Rahkola, Jeremy T; Nick, Heidi J; Smythies, Lesley E; McConnell, Michelle; Fowler, Mary G; Smith, Phillip D; Janoff, Edward N

    2015-01-01

    Breast milk is a vehicle of infection and source of protection in post-natal mother-to-child HIV-1 transmission (MTCT). Understanding the mechanism by which breast milk limits vertical transmission will provide critical insight into the design of preventive and therapeutic approaches to interrupt HIV-1 mucosal transmission. However, characterization of the inhibitory activity of breast milk in human intestinal mucosa, the portal of entry in postnatal MTCT, has been constrained by the limited availability of primary mucosal target cells and tissues to recapitulate mucosal transmission ex vivo. Here, we characterized the impact of skimmed breast milk, breast milk antibodies (Igs) and non-Ig components from HIV-1-infected Ugandan women on the major events of HIV-1 mucosal transmission using primary human intestinal cells a