Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Angew Chem Int Ed Engl ; 62(9): e202211794, 2023 Feb 20.
Article in English | MEDLINE | ID: mdl-36524997

ABSTRACT

A flurry of recent research has centered on harnessing the power of nickel catalysis in organic synthesis. These efforts have been bolstered by contemporaneous development of well-defined nickel (pre)catalysts with diverse structure and reactivity. In this report, we present ten different bench-stable, 18-electron, formally zero-valent nickel-olefin complexes that are competent pre-catalysts in various reactions. Our investigation includes preparations of novel, bench-stable Ni(COD)(L) complexes (COD=1,5-cyclooctadiene), in which L=quinone, cyclopentadienone, thiophene-S-oxide, and fulvene. Characterization by NMR, IR, single-crystal X-ray diffraction, cyclic voltammetry, thermogravimetric analysis, and natural bond orbital analysis sheds light on the structure, bonding, and properties of these complexes. Applications in an assortment of nickel-catalyzed reactions underscore the complementary nature of the different pre-catalysts within this toolkit.

2.
J Am Chem Soc ; 144(42): 19337-19343, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36222701

ABSTRACT

An asymmetric 1,2-dicarbofunctionalization of unactivated alkenes with aryl iodides and aryl/alkenylboronic esters under nickel/bioxazoline catalysis is disclosed. A wide array of aryl and alkenyl nucleophiles are tolerated, furnishing the products in good yield and with high enantioselectivity. In addition to terminal alkenes, 1,2-disubstituted internal alkenes participate in the reaction, establishing two contiguous stereocenters with high diastereoselectivity and moderate enantioselectivity. A combination of experimental and computational techniques shed light on the mechanism of the catalytic transformation, pointing to a closed-shell pathway with an enantiodetermining migratory insertion step, where stereoinduction arises from synergistic interactions between the sterically bulky achiral sulfonamide directing group and the hemilabile bidentate ligand.


Subject(s)
Alkenes , Nickel , Ligands , Iodides , Catalysis , Esters , Sulfonamides
3.
Org Lett ; 23(24): 9337-9342, 2021 12 17.
Article in English | MEDLINE | ID: mdl-34499517

ABSTRACT

An operationally simple, scalable, and chemoselective method for the direct phosphorylation of alcohols using a P(V)-approach based on the Ψ-reagent platform is disclosed. The method features a broad substrate scope of utility in both simple and complex settings and provides access to valuable phosphorylated alcohols that would be otherwise difficult to obtain.


Subject(s)
Alcohols
4.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Article in English | MEDLINE | ID: mdl-33836615

ABSTRACT

Gram-positive bacteria assemble a multilayered cell wall that provides tensile strength to the cell. The cell wall is composed of glycan strands cross-linked by nonribosomally synthesized peptide stems. Herein, we modify the peptide stems of the Gram-positive bacterium Bacillus subtilis with noncanonical electrophilic d-amino acids, which when in proximity to adjacent stem peptides form novel covalent 5,3-cross-links. Approximately 20% of canonical cell-wall cross-links can be replaced with synthetic cross-links. While a low level of synthetic cross-link formation does not affect B. subtilis growth and phenotype, at higher levels cell growth is perturbed and bacteria elongate. A comparison of the accumulation of synthetic cross-links over time in Gram-negative and Gram-positive bacteria highlights key differences between them. The ability to perturb cell-wall architecture with synthetic building blocks provides a novel approach to studying the adaptability, elasticity, and porosity of bacterial cell walls.


Subject(s)
Cell Wall/chemistry , Gram-Positive Rods/chemistry , Peptidoglycan/chemistry , Amino Acids/chemistry , Amino Acids/metabolism , Bacillus subtilis/chemistry , Bacillus subtilis/cytology , Bacillus subtilis/growth & development , Bacillus subtilis/metabolism , Cell Wall/metabolism , Gram-Negative Bacteria/chemistry , Gram-Negative Bacteria/cytology , Gram-Negative Bacteria/metabolism , Gram-Positive Rods/cytology , Gram-Positive Rods/growth & development , Gram-Positive Rods/metabolism , Peptidoglycan/metabolism , Peptidyl Transferases/genetics , Peptidyl Transferases/metabolism , Phenotype
5.
ACS Cent Sci ; 6(11): 2117, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-33274288

ABSTRACT

[This corrects the article DOI: 10.1021/acscentsci.0c00680.].

6.
ACS Cent Sci ; 6(10): 1789-1799, 2020 Oct 28.
Article in English | MEDLINE | ID: mdl-33145415

ABSTRACT

Controlled site-specific bioconjugation through chemical methods to native DNA remains an unanswered challenge. Herein, we report a simple solution to achieve this conjugation through the tactical combination of two recently developed technologies: one for the manipulation of DNA in organic media and another for the chemoselective labeling of alcohols. Reversible adsorption of solid support (RASS) is employed to immobilize DNA and facilitate its transfer into dry acetonitrile. Subsequent reaction with P(V)-based Ψ reagents takes place in high yield with exquisite selectivity for the exposed 3' or 5' alcohols on DNA. This two-stage process, dubbed SENDR for Synthetic Elaboration of Native DNA by RASS, can be applied to a multitude of DNA conformations and sequences with a variety of functionalized Ψ reagents to generate useful constructs.

7.
Bioorg Med Chem Lett ; 30(16): 127356, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32631553

ABSTRACT

Misfolding and aggregation of immunoglobulin light chains (LCs) leads to the degeneration of post-mitotic tissue in the disease immunoglobulin LC amyloidosis (AL). We previously reported the discovery of small molecule kinetic stabilizers of the native dimeric structure of full-length LCs, which slow or stop the LC aggregation cascade at the outset. A predominant structural category of kinetic stabilizers emerging from the high-throughput screen are coumarins substituted at the 7-position, which bind at the interface between the two variable domains of the light chain dimer. Here, we report the binding mode of another, more polar, LC kinetic stabilizer chemotype, 3,5-substituted hydantoins. Computational docking, solution nuclear magnetic resonance experiments, and x-ray crystallography show that the aromatic substructure emerging from the hydantoin 3-position occupies the same LC binding site as the coumarin ring. Notably, the hydantoin ring extends beyond the binding site mapped out by the coumarin hits. The hydantoin ring makes hydrogen bonds with both LC monomers simultaneously. The alkyl substructure at the hydantoin 5-position partially occupies a novel binding pocket proximal to the pocket occupied by the coumarin substructure. Overall, the hydantoin structural data suggest that a larger area of the LC variable-domain-variable-domain dimer interface is amenable to small molecule binding than previously demonstrated, which should facilitate development of more potent full-length LC kinetic stabilizers.


Subject(s)
Hydantoins/pharmacology , Immunoglobulin Light Chains/chemistry , Crystallography, X-Ray , Dose-Response Relationship, Drug , Humans , Hydantoins/chemistry , Hydrogen Bonding , Kinetics , Models, Molecular , Molecular Structure , Protein Stability/drug effects , Structure-Activity Relationship
8.
Nat Catal ; 3(1): 23-29, 2020.
Article in English | MEDLINE | ID: mdl-32420528

ABSTRACT

Enantioenriched α-aminoboronic acids play a unique role in medicinal chemistry and have emerged as privileged pharmacophores in proteasome inhibitors. Additionally, they represent synthetically useful chiral building blocks in organic synthesis. Recently, CuH-catalyzed asymmetric alkene hydrofunctionalization has become a powerful tool to construct stereogenic carbon centers. In contrast, applying CuH cascade catalysis to achieve reductive 1,1-difunctionalization of alkynes remains an important, but largely unaddressed, synthetic challenge. Herein, we report an efficient strategy to synthesize α-aminoboronates via CuH-catalyzed hydroboration/hydroamination cascade of readily available alkynes. Notably, this transformation selectively delivers the desired 1,1-heterodifunctionalized product in favor of alternative homodifunctionalized, 1,2-heterodifunctionalized, or reductively monofunctionalized byproducts, thereby offering rapid access to these privileged scaffolds with high chemo-, regio- and enantioselectivity.

9.
J Am Chem Soc ; 142(19): 8972-8979, 2020 05 13.
Article in English | MEDLINE | ID: mdl-32302104

ABSTRACT

The emerging use of covalent ligands as chemical probes and drugs would benefit from an expanded repertoire of cysteine-reactive electrophiles for efficient and diverse targeting of the proteome. Here we use the endogenous electrophile sensor of mammalian cells, the KEAP1-NRF2 pathway, to discover cysteine-reactive electrophilic fragments from a reporter-based screen for NRF2 activation. This strategy identified a series of 2-sulfonylpyridines that selectively react with biological thiols via nucleophilic aromatic substitution (SNAr). By tuning the electrophilicity and appended recognition elements, we demonstrate the potential of the 2-sulfonylpyridine reactive group with the discovery of a selective covalent modifier of adenosine deaminase (ADA). Targeting a cysteine distal to the active site, this molecule attenuates the enzymatic activity of ADA and inhibits proliferation of lymphocytic cells. This study introduces a modular and tunable SNAr-based reactive group for targeting reactive cysteines in the human proteome and illustrates the pharmacological utility of this electrophilic series.


Subject(s)
Cysteine/chemistry , Pyridines/chemistry , Sulfur Dioxide/chemistry , Cell Line, Tumor , Density Functional Theory , Humans , Molecular Structure
10.
Angew Chem Int Ed Engl ; 59(19): 7377-7383, 2020 05 04.
Article in English | MEDLINE | ID: mdl-32050046

ABSTRACT

DNA encoded libraries (DEL) have shown promise as a valuable technology for democratizing the hit discovery process. Although DEL provides relatively inexpensive access to libraries of unprecedented size, their production has been hampered by the idiosyncratic needs of the encoding DNA tag relegating DEL compatible chemistry to dilute aqueous environments. Recently reversible adsorption to solid support (RASS) has been demonstrated as a promising method to expand DEL reactivity using standard organic synthesis protocols. Here we demonstrate a suite of on-DNA chemistries to incorporate medicinally relevant and C-S, C-P and N-S linkages into DELs, which are underrepresented in the canonical methods.


Subject(s)
DNA/chemical synthesis , Adsorption , Chemistry Techniques, Synthetic , Combinatorial Chemistry Techniques , Drug Discovery , Indicators and Reagents , Small Molecule Libraries , Solubility , Sulfones/chemistry , Sulfoxides/chemistry
11.
J Clin Invest ; 129(11): 4769-4785, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31566579

ABSTRACT

BACKGROUNDRV144 is the only preventive HIV vaccine regimen demonstrating efficacy in humans. Attempting to build upon RV144 immune responses, we conducted a phase 1, multicenter, randomized, double-blind trial to assess the safety and immunogenicity of regimens substituting the DNA-HIV-PT123 (DNA) vaccine for ALVAC-HIV in different sequences or combinations with AIDSVAX B/E (protein).METHODSOne hundred and four HIV-uninfected participants were randomized to 4 treatment groups (T1, T2, T3, and T4) and received intramuscular injections at 0, 1, 3, and 6 months (M): T1 received protein at M0 and M1 and DNA at M3 and M6; T2 received DNA at M0 and M1 and protein at M3 and M6; T3 received DNA at M0, M1, M3, and M6 with protein coadministered at M3 and M6; and T4 received protein and DNA coadministered at each vaccination visit.RESULTSAll regimens were well tolerated. Antibodies binding to gp120 and V1V2 scaffold were observed in 95%-100% of participants in T3 and T4, two weeks after final vaccination at high magnitude. While IgG3 responses were highest in T3, a lower IgA/IgG ratio was observed in T4. Binding antibodies persisted at 12 months in 35%-100% of participants. Antibody-dependent cell-mediated cytotoxicity and tier 1 neutralizing-antibody responses had higher response rates for T3 and T4, respectively. CD4+ T cell responses were detectable in all treatment groups (32%-64%) without appreciable CD8+ T cell responses.CONCLUSIONThe DNA/protein combination regimens induced high-magnitude and long-lasting HIV V1V2-binding antibody responses, and early coadministration of the 2 vaccines led to a more rapid induction of these potentially protective responses.TRIAL REGISTRATIONClinicalTrials.gov NCT02207920.FUNDINGNational Institute of Allergy and Infectious Diseases (NIAID) grants UM1 AI068614, UM1 AI068635, UM1 AI068618, UM1 AI069511, UM1 AI069470, UM1 AI069534, P30 AI450008, UM1 AI069439, UM1 AI069481, and UM1 AI069496; the National Center for Advancing Translational Sciences, NIH (grant UL1TR001873); and the Bill & Melinda Gates Foundation (grant OPP52845).


Subject(s)
AIDS Vaccines/administration & dosage , HIV Antibodies/immunology , HIV Envelope Protein gp120/administration & dosage , Immunization, Secondary , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Vaccines, DNA/administration & dosage , AIDS Vaccines/immunology , Adolescent , Adult , Antibodies, Neutralizing/immunology , Antibody-Dependent Cell Cytotoxicity/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Female , HIV Envelope Protein gp120/immunology , Humans , Male , Middle Aged , Vaccines, DNA/immunology
12.
J Am Chem Soc ; 141(25): 9998-10006, 2019 06 26.
Article in English | MEDLINE | ID: mdl-31136164

ABSTRACT

DNA Encoded Libraries have proven immensely powerful tools for lead identification. The ability to screen billions of compounds at once has spurred increasing interest in DEL development and utilization. Although DEL provides access to libraries of unprecedented size and diversity, the idiosyncratic and hydrophilic nature of the DNA tag severely limits the scope of applicable chemistries. It is known that biomacromolecules can be reversibly, noncovalently adsorbed and eluted from solid supports, and this phenomenon has been utilized to perform synthetic modification of biomolecules in a strategy we have described as reversible adsorption to solid support (RASS). Herein, we present the adaptation of RASS for a DEL setting, which allows reactions to be performed in organic solvents at near anhydrous conditions opening previously inaccessible chemical reactivities to DEL. The RASS approach enabled the rapid development of C(sp2)-C(sp3) decarboxylative cross-couplings with broad substrate scope, an electrochemical amination (the first electrochemical synthetic transformation performed in a DEL context), and improved reductive amination conditions. The utility of these reactions was demonstrated through a DEL-rehearsal in which all newly developed chemistries were orchestrated to afford a compound rich in diverse skeletal linkages. We believe that RASS will offer expedient access to new DEL reactivities, expanded chemical space, and ultimately more drug-like libraries.


Subject(s)
Aniline Compounds/chemical synthesis , Combinatorial Chemistry Techniques/methods , DNA/chemistry , Piperidines/chemical synthesis , Quaternary Ammonium Compounds/chemistry , Proof of Concept Study
13.
J Am Chem Soc ; 141(16): 6726-6739, 2019 04 24.
Article in English | MEDLINE | ID: mdl-30943023

ABSTRACT

Historically accessed through two-electron, anionic chemistry, ketones, alcohols, and amines are of foundational importance to the practice of organic synthesis. After placing this work in proper historical context, this Article reports the development, full scope, and a mechanistic picture for a strikingly different way of forging such functional groups. Thus, carboxylic acids, once converted to redox-active esters (RAEs), can be utilized as formally nucleophilic coupling partners with other carboxylic derivatives (to produce ketones), imines (to produce benzylic amines), or aldehydes (to produce alcohols). The reactions are uniformly mild, operationally simple, and, in the case of ketone synthesis, broad in scope (including several applications to the simplification of synthetic problems and to parallel synthesis). Finally, an extensive mechanistic study of the ketone synthesis is performed to trace the elementary steps of the catalytic cycle and provide the end-user with a clear and understandable rationale for the selectivity, role of additives, and underlying driving forces involved.


Subject(s)
Alcohols/chemistry , Alcohols/chemical synthesis , Amines/chemistry , Amines/chemical synthesis , Ketones/chemistry , Ketones/chemical synthesis , Chemistry Techniques, Synthetic , Free Radicals/chemistry
14.
PLoS One ; 13(9): e0202753, 2018.
Article in English | MEDLINE | ID: mdl-30235286

ABSTRACT

BACKGROUND: The addition of plasmid cytokine adjuvants, electroporation, and live attenuated viral vectors may further optimize immune responses to DNA vaccines in heterologous prime-boost combinations. The objective of this study was to test the safety and tolerability of a novel prime-boost vaccine regimen incorporating these strategies with different doses of IL-12 plasmid DNA adjuvant. METHODS: In a phase 1 study, 88 participants received an HIV-1 multiantigen (gag/pol, env, nef/tat/vif) DNA vaccine (HIV-MAG, 3000 µg) co-administered with IL-12 plasmid DNA adjuvant at 0, 250, 1000, or 1500 µg (N = 22/group) given intramuscularly with electroporation (Ichor TriGrid™ Delivery System device) at 0, 1 and 3 months; followed by attenuated recombinant vesicular stomatitis virus, serotype Indiana, expressing HIV-1 Gag (VSV-Gag), 3.4 ⊆ 107 plaque-forming units (PFU), at 6 months; 12 others received placebo. Injections were in both deltoids at each timepoint. Participants were monitored for safety and tolerability for 15 months. RESULTS: The dose of IL-12 pDNA did not increase pain scores, reactogenicity, or adverse events with the co-administered DNA vaccine, or following the VSV-Gag boost. Injection site pain and reactogenicity were common with intramuscular injections with electroporation, but acceptable to most participants. VSV-Gag vaccine often caused systemic reactogenicity symptoms, including a viral syndrome (in 41%) of fever, chills, malaise/fatigue, myalgia, and headache; and decreased lymphocyte counts 1 day after vaccination. CONCLUSIONS: HIV-MAG DNA vaccine given by intramuscular injection with electroporation was safe at all doses of IL-12 pDNA. The VSV-Gag vaccine at this dose was associated with fever and viral symptoms in some participants, but the vaccine regimens were safe and generally well-tolerated. TRIAL REGISTRATION: Clinical Trials.gov NCT01578889.


Subject(s)
AIDS Vaccines/administration & dosage , Genetic Vectors/administration & dosage , Interleukin-12/genetics , Vaccines, Attenuated/administration & dosage , Vaccines, DNA/administration & dosage , Vesicular stomatitis Indiana virus/genetics , AIDS Vaccines/adverse effects , Adult , Combined Modality Therapy , Double-Blind Method , Electroporation , Female , Genetic Vectors/adverse effects , HIV-1 , Healthy Volunteers , Humans , Immunization, Secondary , Injections, Intramuscular , Male , Middle Aged , Plasmids/genetics , Vaccines, Attenuated/adverse effects , Vaccines, DNA/adverse effects , Young Adult , gag Gene Products, Human Immunodeficiency Virus
15.
AIDS Res Hum Retroviruses ; 34(3): 307-313, 2018 03.
Article in English | MEDLINE | ID: mdl-29297230

ABSTRACT

Therapeutic vaccination has the potential to contribute to functional HIV cure strategies. However, to show functional HIV cure, study participants must be taken off combination antiretroviral therapy (cART). The availability of suitable biomarkers that can predict viral load (VL) or CD4 count outcomes following therapeutic HIV vaccination would reduce the risks associated with cART interruption in such studies. This report sought to determine baseline and postvaccination biomarker predictors of vaccine effect (VE) on VL and CD4 counts following cART interruption in a double-blind, randomized phase 2 study of the peptide-based therapeutic HIV vaccine, Vacc-4x (n = 93), versus placebo (n = 43). Antibody responses to a novel envelope glycoprotein antigen, C5/gp41732-744, and three safety marker measurements [C-reactive protein (CRP), white blood cell, and lactate dehydrogenase] were considered. Interaction tests in univariate and multivariate linear regression models were used to estimate the effect of biomarkers on VE, defined as the VL or CD4 count difference in Vacc-4x versus placebo groups. The reported q-values (considered significant for hypothesis-generating purposes if ≤0.2) accounted for multiple comparisons using the false discovery rate method. Data were analyzed from all available 58 Vacc-4x and 25 placebo recipients before cART resumption. Lower postvaccination fold-change over baseline of CRP concentration (interaction p- (q-) value = 0.005 (0.11) for VL) and higher fold-change of anti-C5/gp41732-744 antibody levels (0.005 (0.11) for VL and 0.009 (0.20) for CD4) were associated with Vacc-4x benefit. These findings suggest potential roles for inflammation and immune activation markers in predicting therapeutic HIV VE.


Subject(s)
AIDS Vaccines/immunology , AIDS Vaccines/pharmacology , C-Reactive Protein/drug effects , HIV Infections/immunology , HIV Infections/prevention & control , HIV-1/immunology , Adult , Antibody Formation/drug effects , C-Reactive Protein/metabolism , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Dose-Response Relationship, Immunologic , Double-Blind Method , Endpoint Determination , Female , Humans , Male , Middle Aged , Viral Load/drug effects , Viral Load/immunology , Young Adult
16.
Nutrients ; 9(12)2017 Dec 15.
Article in English | MEDLINE | ID: mdl-29244743

ABSTRACT

In a double-blind, crossover, randomized and placebo-controlled trial; 28 men and women ingested a placebo (PLA), 3 g of creatine nitrate (CNL), and 6 g of creatine nitrate (CNH) for 6 days. Participants repeated the experiment with the alternate supplements after a 7-day washout. Hemodynamic responses to a postural challenge, fasting blood samples, and bench press, leg press, and cycling time trial performance and recovery were assessed. Data were analyzed by univariate, multivariate, and repeated measures general linear models (GLM). No significant differences were found among treatments for hemodynamic responses, clinical blood markers or self-reported side effects. After 5 days of supplementation, one repetition maximum (1RM) bench press improved significantly for CNH (mean change, 95% CI; 6.1 [3.5, 8.7] kg) but not PLA (0.7 [-1.6, 3.0] kg or CNL (2.0 [-0.9, 4.9] kg, CNH, p = 0.01). CNH participants also tended to experience an attenuated loss in 1RM strength during the recovery performance tests following supplementation on day 5 (PLA: -9.3 [-13.5, -5.0], CNL: -9.3 [-13.5, -5.1], CNH: -3.9 [-6.6, -1.2] kg, p = 0.07). After 5 days, pre-supplementation 1RM leg press values increased significantly, only with CNH (24.7 [8.8, 40.6] kg, but not PLA (13.9 [-15.7, 43.5] or CNL (14.6 [-0.5, 29.7]). Further, post-supplementation 1RM leg press recovery did not decrease significantly for CNH (-13.3 [-31.9, 5.3], but did for PLA (-30.5 [-53.4, -7.7] and CNL (-29.0 [-49.5, -8.4]). CNL treatment promoted an increase in bench press repetitions at 70% of 1RM during recovery on day 5 (PLA: 0.4 [-0.8, 1.6], CNL: 0.9 [0.35, 1.5], CNH: 0.5 [-0.2, 0.3], p = 0.56), greater leg press endurance prior to supplementation on day 5 (PLA: -0.2 [-1.6, 1.2], CNL: 0.9 [0.2, 1.6], CNH: 0.2 [-0.5, 0.9], p = 0.25) and greater leg press endurance during recovery on day 5 (PLA: -0.03 [-1.2, 1.1], CNL: 1.1 [0.3, 1.9], CNH: 0.4 [-0.4, 1.2], p = 0.23). Cycling time trial performance (4 km) was not affected. Results indicate that creatine nitrate supplementation, up to a 6 g dose, for 6 days, appears to be safe and provide some ergogenic benefit.


Subject(s)
Athletic Performance , Creatine/administration & dosage , Dietary Supplements , Nitrates/administration & dosage , Performance-Enhancing Substances/administration & dosage , Adolescent , Adult , Animals , Anthropometry , Bicycling , Body Composition , Creatine/blood , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Female , Hemodynamics , Humans , Male , Muscle Strength/drug effects , Muscle, Skeletal/drug effects , Muscle, Skeletal/physiology , Nitrates/blood , Performance-Enhancing Substances/blood , Physical Endurance , Surveys and Questionnaires , Treatment Outcome , Young Adult
17.
EBioMedicine ; 24: 195-204, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28970080

ABSTRACT

BACKGROUND: In a placebo-controlled trial of the peptide-based therapeutic HIV-1 p24Gag 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. METHODS: 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 (VEVL) or CD4 count (VECD4). FINDINGS: A lower fold-change of CD4+ T-cell proliferation was associated with VECD4 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 VEVL at week 44 (p=0.047, q=0.07). A higher fold-change of TNF-α was associated with VEVL 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 VEVL at week 48 (p=0.017, q=0.036). TNF-α levels (>median) were associated with VECD4 at week 48 (p=0.009, q=0.009). INTERPRETATION: These exploratory analyses highlight the potential value of investigating biomarkers in T-cell proliferation supernatants for VE in clinical studies.


Subject(s)
AIDS Vaccines/administration & dosage , CD4-Positive T-Lymphocytes/cytology , HIV Infections/drug therapy , HIV Infections/immunology , HIV-1/physiology , Viral Load/drug effects , AIDS Vaccines/pharmacology , Adult , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/drug effects , Cell Proliferation/drug effects , Female , HIV-1/immunology , Humans , Immunity, Cellular , Interleukin-6/metabolism , Male , Middle Aged , Treatment Outcome , Tumor Necrosis Factor-alpha/metabolism , Young Adult
18.
PLoS One ; 12(7): e0179597, 2017.
Article in English | MEDLINE | ID: mdl-28727817

ABSTRACT

BACKGROUND: A phase 1 trial of a clade B HIV vaccine in HIV-uninfected adults evaluated the safety and immunogenicity of a DNA prime co-expressing GM-CSF (Dg) followed by different numbers and intervals of modified vaccinia Ankara Boosts (M). Both vaccines produce virus-like particles presenting membrane-bound Env. METHODS: Four US sites randomized 48 participants to receiving 1/10th the DNA dose as DgDgMMM given at 0, 2, 4, 6 and 8 months, or full dose DgDgM_M or DgDgMM_M regimens, given at 0, 2, 4, and 8 months, and 0, 2, 4, 6, and 10 months, respectively. Peak immunogenicity was measured 2 weeks post-last vaccination. RESULTS: All regimens were well tolerated and safe. Full dose DgDgM_M and DgDgMM_M regimens generated Env-specific IgG to HIV-1 Env in >90%, IgG3 in >80%, and IgA in <20% of participants. Responses to gp140 and gp41 targets were more common and of higher magnitude than to gp120 and V1V2. The gp41 antibody included reactivity to the conserved immunodominant region with specificities known to mediate virus capture and phagocytosis and did not cross-react with a panel of intestinal flora antigens. The 3rd dose of MVA increased the avidity of elicited antibody (7.5% to 39%), the ADCC response to Bal gp120 (14% to 64%), and the one-year durability of the IgG3 responses to gp41 by 4-fold (13% vs. 3.5% retention of peak response). The co-expressed GM-CSF did not enhance responses over those in trials testing this vaccine without GM-CSF. CONCLUSION: This DNA/MVA prime-boost regimen induced durable, functional humoral responses that included ADCC, high antibody avidity, and Env IgG1 and IgG3 binding responses to the immunodominant region of gp41. The third, spaced MVA boost improved the overall quality of the antibody response. These products without co-expressed GM-CSF but combined with protein boosts will be considered for efficacy evaluation. TRIAL REGISTRATION: ClinicalTrials.gov NCT01571960.


Subject(s)
AIDS Vaccines/immunology , HIV Antibodies , Vaccines, DNA/immunology , AIDS Vaccines/adverse effects , Adolescent , Adult , Double-Blind Method , Female , Granulocyte-Macrophage Colony-Stimulating Factor , Humans , Male , Middle Aged , Vaccination/methods , Vaccines, DNA/adverse effects , Young Adult
19.
J Infect Dis ; 215(9): 1376-1385, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28199679

ABSTRACT

Background: It is important to identify vaccine-induced immune responses that predict the preventative efficacy of a human immunodeficiency virus (HIV)-1 vaccine. We assessed T-cell response markers as correlates of risk in the HIV Vaccine Trials Network (HVTN) 505 HIV-1 vaccine efficacy trial. Methods: 2504 participants were randomized to DNA/rAd5 vaccine or placebo, administered at weeks 0, 4, 8, and 24. Peripheral blood mononuclear cells were obtained at week 26 from all 25 primary endpoint vaccine cases and 125 matched vaccine controls, and stimulated with vaccine-insert-matched peptides. Primary variables were total HIV-1-specific CD4+ T-cell magnitude and Env-specific CD4+ polyfunctionality. Four secondary variables were also assessed. Immune responses were evaluated as predictors of HIV-1 infection among vaccinees using Cox proportional hazards models. Machine learning analyses identified immune response combinations best predicting HIV-1 infection. Results: We observed an unexpectedly strong inverse correlation between Env-specific CD8+ immune response magnitude and HIV-1 infection risk (hazard ratio [HR] = 0.18 per SD increment; P = .04) and between Env-specific CD8+ polyfunctionality and infection risk (HR = 0.34 per SD increment; P < .01). Conclusions: Further research is needed to determine if these immune responses are predictors of vaccine efficacy or markers of natural resistance to HIV-1 infection.


Subject(s)
AIDS Vaccines/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , HIV Infections/immunology , AIDS Vaccines/administration & dosage , Adenoviridae/genetics , Analysis of Variance , Computational Biology , Cytokines/immunology , Genetic Vectors , HIV Infections/prevention & control , Humans , Machine Learning , Risk
20.
Appl Physiol Nutr Metab ; 42(2): 216-227, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28044449

ABSTRACT

While commercial dietary weight-loss programs typically advise exercise, few provide actual programing. The goal of this study was to compare the Curves Complete 90-day Challenge (CC, n = 29), which incorporates exercising and diet, to programs advocating exercise (Weight Watchers Points Plus (WW, n = 29), Jenny Craig At Home (JC, n = 27), and Nutrisystem Advance Select (NS, n = 28)) or control (n = 20) on metabolic syndrome (MetS) and weight loss. We randomized 133 sedentary, overweight women (age, 47 ± 11 years; body mass, 86 ± 14 kg; body mass index, 35 ± 6 kg/m2) into respective treatment groups for 12 weeks. Data were analyzed using chi square and general linear models adjusted for age and respective baseline measures. Data are means ± SD or mean change ± 95% confidence intervals (CIs). We observed a significant trend for a reduction in energy intake for all treatment groups and significant weight loss for all groups except control: CC (-4.32 kg; 95% CI, -5.75, -2.88), WW (-4.31 kg; 95% CI, -5.82, -2.96), JC (-5.34 kg; 95% CI, -6.86, -3.90), NS (-5.03 kg; 95% CI, -6.49, -3.56), and control (0.16 kg, 95% CI, -1.56, 1.89). Reduced MetS prevalence was observed at follow-up for CC (35% vs. 14%, adjusted standardized residuals (adjres.) = 3.1), but not WW (31% vs. 28% adjres. = 0.5), JC (37% vs. 42%, adjres. = -0.7), NS (39% vs. 50% adjres. = -1.5), or control (45% vs. 55% adjres. = -1.7). While all groups improved relative fitness (mL·kg-1·min-1) because of weight loss, only the CC group improved absolute fitness (L/min). In conclusion, commercial programs offering concurrent diet and exercise programming appear to offer greater improvements in MetS prevalence and cardiovascular function after 12 weeks of intervention.


Subject(s)
Diet, Reducing , Exercise , Metabolic Syndrome/prevention & control , Obesity/diet therapy , Overweight/diet therapy , Body Mass Index , Cardiorespiratory Fitness , Combined Modality Therapy/economics , Diet, Reducing/economics , Double-Blind Method , Energy Intake , Female , Follow-Up Studies , Humans , Insulin Resistance , Metabolic Syndrome/epidemiology , Metabolic Syndrome/etiology , Middle Aged , Obesity/metabolism , Obesity/physiopathology , Obesity/therapy , Overweight/metabolism , Overweight/physiopathology , Overweight/therapy , Patient Compliance , Prevalence , Resistance Training , Risk Factors , Sedentary Behavior , Texas/epidemiology , Weight Loss
SELECTION OF CITATIONS
SEARCH DETAIL
...