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Now showing items 1 - 16 of 16

  • Urine Antigen Detection as an Aid to Diagnose Invasive Aspergillosis

    Marr, Kieren A.   Datta, Kausik   Mehta, Seema   Ostrander, Darin B.   Rock, Michelle   Francis, Jesse   Feldmesser, Marta  

    Background. Establishing rapid diagnoses of invasive aspergillosis (IA) is a priority tests that detect galactomannan and beta-D-glucan are available, but are technically cumbersome and rely on invasive sampling (blood or bronchoalveolar lavage). Methods. We optimized a lateral flow dipstick assay using the galactofuranose-specific monoclonal antibody (mAb476), which recognizes urine antigens after Aspergillus fumigatus pulmonary infection in animals. Urine samples were obtained from a cohort of 78 subjects undergoing evaluation for suspected invasive fungal infections, and stored frozen until testing. Urine was processed by centrifugation through desalting columns and exposed to dipsticks. Reviewers blinded to clinical diagnoses graded results. Western blots were performed on urine samples from 2 subjects to characterize mAb476-reactive antigens. Results. Per-patient sensitivity and specificity for diagnosis of proven or probable IA in the overall cohort was 80% (95% confidence interval [CI], 61.4%-92.3%) and 92% (95% CI, 74%-99%), respectively. In the subgroup with cancer, sensitivity was 89.5% (95% CI, 66.7%-98.7%) and specificity was 90.9% (95% CI, 58.7%-99.8%); among all others, sensitivity and specificity were 63.6% (95% CI, 30.8%-89.1%) and 92.9% (95% CI, 66.1%-99.8%), respectively. Eliminating lung transplant recipients with airway disease increased sensitivity in the noncancer cohort (85.7% [95% CI, 42.1%-99.6%]). Semiquantitative urine assay results correlated with serum galactomannan indices. Western blots demonstrated mAb476-reactive antigens in urine from cases, ranging between 26 kDa and 35 kDa in size. Conclusions. Urine testing using mAb476 may be used as an aid to diagnose IA in high-risk patients.
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  • An HIV gp120-CD4 Immunogen Does Not Elicit Autoimmune Antibody Responses in Cynomolgus Macaques

    Schwartz, Jennifer A.   Prado, Ilia   Misamore, Johnathan   Weiss, Deborah   Francis, Jesse   Pal, Ranajit   Huaman, Maria   Cristillo, Anthony   Lewis, George K.   Gallo, Robert C.   DeVico, Anthony L.   Fouts, Timothy R.  

    A promising concept for human immunodeficiency virus (HIV) vaccines focuses immunity on the highly conserved transition state structures and epitopes that appear when the HIV glycoprotein gp120 binds to its receptor, CD4. We are developing chimeric antigens (full-length single chain, or FLSC) in which gp120 and CD4 sequences are flexibly linked to allow stable intrachain complex formation between the two moieties (A. DeVico et al., Proc Natl Acad Sci U S A 104: 17477-17482, 2007, doi: 10.1073/pnas.0707399104; T. R. Fouts et al., J Virol 74: 11427-11436, 2000, doi: 10.1128/JVI.74.24.11427-11436.2000). Proof of concept studies with nonhuman primates show that FLSC elicited heterologous protection against simian-human immunodeficiency virus (SHIV)/simian immunodeficiency virus (SIV) (T. R. Fouts et al., Proc Natl Acad Sci U S A 112: E992-E999, 2016, doi: 10.1073/pnas.1423669112), which correlated with antibodies against transition state gp120 epitopes. Nevertheless, advancement of any vaccine that comprises gp120-CD4 complexes must consider whether the CD4 component breaks tolerance and becomes immunogenic in the autologous host. To address this, we performed an immunotoxicology study with cynomolgus macaques vaccinated with either FLSC or a rhesus variant of FLSC containing macaque CD4 sequences (rhFLSC). Enzyme-linked immunosorbent assay (ELISA) binding titers, primary CD3(+) T cell staining, and temporal trends in T cell subset frequencies served to assess whether anti-CD4 autoantibody responses were elicited by vaccination. We find that immunization with multiple high doses of rhFLSC did not elicit detectable antibody titers despite robust responses to rhFLSC. In accordance with these findings, immunized animals had no changes in circulating CD4(+) T cell counts or evidence of autoantibody reactivity with cell surface CD4 on primary naive macaque T cells. Collectively, these studies show that antigens using CD4 sequences to stabilize transition state gp120 structures are unlikely to elicit autoimmune antibody responses, supporting the advancement of gp120-CD4 complex-based antigens, such as FLSC, into clinical testing.
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  • Energy Transfer-Based Biosensing of Protease Activity Measured Using an Electroluminescent Platform

    Sapsford, Kim E.   Sun, Steven   Francis, Jesse   Kostov, Yordan   Rasooly, Avraham   Farrell, Dorothy   Mattoussi, Hedi   Medintze, Igor L.  

    We present a biosensing platform that uses spatial electroluminescent (EL) illumination combined with charge-coupled device (CCD)-based detection for fluorescence measurements. The resulting EL-CCD detector platform was used to monitor different protease activities with substrates labeled for fluorescence resonance energy transfer (FRET)-based assays. The first uses a commercial FITC/DABCYL-SNAP-25 peptide substrate to monitor the activity of the light chain derivative (LcA) of botulinum neurotoxin A, achieving a limit of detection (LOD) of 1.25 nM (62 ng/ml). The second protease activity assay measured trypsin proteolysis using peptide substrates immobilized onto semiconductor quantum dot (QD) nanoparticles with a LOD of 6.2 nM trypsin (140 ng/ml). The specific ovomucoid inhibition of trypsin activity was also monitored. The highlighted studies clearly demonstrate the utility of the EL-CCD detector platform for monitoring fluorescent-based protease activity assays with potential healthcare applications, including point-of-care diagnostics.
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  • Miniaturized 96-well ELISA chips for staphylococcal enterotoxin B detection using portable colorimetric detector

    Sapsford, Kim E.   Francis, Jesse   Sun, Steven   Kostov, Yordan   Rasooly, Avraham  

    A previously developed fluorescence sensing platform, combining spatial illumination using electroluminescence (EL) semiconductor strips with charge coupled device (CCD)-based detection (EL-CCD), was adapted to a new 96-well chip for colorimetric immunological assays, enhancing the capabilities of the EL-CCD platform. The modified system was demonstrated using a colorimetric-based enzyme linked immunosorbent assay (ELISA) for detection of staphylococcal enterotoxin B (SEB). Limits of detection (LODs) of 3.9 ng/mL (+/- 2.4 ng/mL) SEB were determined with the ELISA chip measured using the EL-CCD platform, following a standard 4-h ELISA protocol. The LODs were comparable to those obtained using standard 96-well ELISA plates measured using a standard laboratory 96-well plate reader. The miniature 96-well ELISA chip however required as little as 5-mu L samples, representing a tenfold reduction in sample volume compared to a standard 96-well ELISA plates. The ELISA chip also demonstrated detection of SEB spiked into various food matrices (milk, mushrooms, and mayonnaise) using limited-to-no sample preparation, with LODs ranging from 3.9 to 18.5 ng/mL depending on the matrix. The EL-CCD platform is versatile, capable of multi-mode detection (e. g., fluorescent and colorimetric along with solution and solid phase assays), and could readily be applied to other field portable or point-of-care applications.
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  • A fluorescence detection platform using spatial electroluminescent excitation for measuring botulinum neurotoxin A activity

    Sapsford, Kim E.   Sun, Steven   Francis, Jesse   Sharma, Shashi   Kostov, Yordan   Rasooly, Avraham  

    Current biodetection illumination technologies (laser. LED, tungsten lamp, etc.) are based on spot illumination with additional optics required when spatial excitation is required. Herein we describe a new approach of spatial illumination based on electroluminescence (EL) semiconductor strips available in several wavelengths, greatly simplifying the biosensor design by eliminating the need for additional optics. This work combines EL excitation with charge-coupled device (CCD) based detection (EL-CCD detector) of fluorescence for developing a simple portable detector for botulinum neurotoxin A (BoTN-A) activity analysis. A Forster Resonance Energy Transfer (FRET) activity assay for BoTN-A was used to both characterize and optimize the EL-CCD detector. The system consists of two modules: (1) the detection module which houses the CCD camera and emission filters, and (2) the excitation and sample module, containing the EL strip, the excitation filter and the 9-well sample chip. The FRET activity assay used in this study utilized a FITC/DABCYL-SNAP-25 peptide substrate in which cleavage of the substrate by BoTN-A, or its light chain derivative (LcA), produced an increase in fluorescence emission. EL-CCD detector measured limits of detection (LODs) were similar to those measured using a standard fluorescent plate reader with valves between 0.625 and 1.25 nM (31-62 ng/ml) for LcA and 0.313 nM (45 ng/ml) for the full toxin, BoTN-A. As far as the authors are aware this is the first demonstration of phosphor-based EL strips being used for the spatial illumination/excitation of a surface, coupled with CCD for point of care detection. Published by Elsevier B.V.
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  • Potential To Streamline Heterologous DNA Prime and NYVAC/Protein Boost HIV Vaccine Regimens in Rhesus Macaques by Employing Improved Antigens

    Asbach, Benedikt   Kliche, Alexander   Koestler, Josef   Perdiguero, Beatriz   Esteban, Mariano   Jacobs, Bertram L.   Montefiori, David C.   LaBranche, Celia C.   Yates, Nicole L.   Tomaras, Georgia D.   Ferrari, Guido   Foulds, Kathryn E.   Roederer, Mario   Landucci, Gary   Forthal, Donald N.   Seaman, Michael S.   Hawkins, Natalie   Self, Steven G.   Sato, Alicia   Gottardo, Raphael   Phogat, Sanjay   Tartaglia, James   Barnett, Susan W.   Burke, Brian   Cristillo, Anthony D.   Weiss, Deborah E.   Francis, Jesse   Galmin, Lindsey   Ding, Song   Heeney, Jonathan L.   Pantaleo, Giuseppe   Wagner, Ralf  

    In a follow-up to the modest efficacy observed in the RV144 trial, researchers in the HIV vaccine field seek to substantiate and extend the results by evaluating other poxvirus vectors and combinations with DNA and protein vaccines. Earlier clinical trials (EuroVacc trials 01 to 03) evaluated the immunogenicity of HIV-1 clade C GagPolNef and gp120 antigens delivered via the pox-viral vector NYVAC. These showed that a vaccination regimen including DNA-C priming prior to a NYVAC-C boost considerably enhanced vaccine-elicited immune responses compared to those with NYVAC-C alone. Moreover, responses were improved by using three as opposed to two DNA-C primes. In the present study, we assessed in nonhuman primates whether such vaccination regimens can be streamlined further by using fewer and accelerated immunizations and employing a novel generation of improved DNA-C and NYVAC-C vaccine candidates designed for higher expression levels and more balanced immune responses. Three different DNA-C prime/NYVAC-C+ protein boost vaccination regimens were tested in rhesus macaques. All regimens elicited vigorous and well-balanced CD8(+) and CD4(+) T cell responses that were broad and polyfunctional. Very high IgG binding titers, substantial antibody-dependent cellular cytotoxicity (ADCC), and modest antibody-dependent cell-mediated virus inhibition (ADCVI), but very low neutralization activity, were measured after the final immunizations. Overall, immune responses elicited in all three groups were very similar and of greater magnitude, breadth, and quality than those of earlier EuroVacc vaccines. In conclusion, these findings indicate that vaccination schemes can be simplified by using improved antigens and regimens. This may offer a more practical and affordable means to elicit potentially protective immune responses upon vaccination, especially in resource-constrained settings. IMPORTANCE Within the EuroVacc clinical trials, we previously assessed the immunogenicity of HIV clade C antigens delivered in a DNA prime/NYVAC boost regimen. The trials showed that the DNA prime crucially improved the responses, and three DNA primes with a NYVAC boost appeared to be optimal. Nevertheless, T cell responses were primarily directed toward Env, and humoral responses were modest. The aim of this study was to assess improved antigens for the capacity to elicit more potent and balanced responses in rhesus macaques, even with various simpler immunization regimens. Our results showed that the novel antigens in fact elicited larger numbers of T cells with a polyfunctional profile and a good Env-GagPolNef balance, as well as high-titer and Fc-functional antibody responses. Finally, comparison of the different schedules indicates that a simpler regimen of only two DNA primes and one NYVAC boost in combination with protein may be very efficient, thus showing that the novel antigens allow for easier immunization protocols.
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  • The book of jesse: a story of youth, illness, and medicineBy Michael Rowe. Washington, DC: The Francis Press, 2002, 336 pages, $25.00 (hardcover)

    HARTMANN, T  

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  • The book of jesse: a story of youth, illness, and medicineBy Michael Rowe. Washington, DC: The Francis Press, 2002, 336 pages, $25.00 (hardcover)

    HARTMANN  

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  • Horizontal Divestiture and the Petroleum Industryby Jesse W. Markham; Anthony P. Hourihan; Francis L. Sterling

    Review by: Allan Zelenitz  

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  • Horizontal Divestiture and the Petroleum Industryby Jesse W. Markham; Anthony P. Hourihan; Francis L. Sterling

    Review by: Allan Zelenitz  

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  • In the Days of My Father General Grantby Jesse R. Grant; Henry Francis Granger

    Review by: Reginald C. McGrane  

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  • In the Days of My Father General Grantby Jesse R. Grant; Henry Francis Granger

    Review by: Reginald C. McGrane  

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  • The Harrisons of Skimeno and particularly of Jesse Burton Harrison and Burton Norvell Harrisonby Fairfax Harrison; Francis Burton Harrison

    Harrison, Fairfax; Harrison, Francis Burton  

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  • The Harrisons of Skimeno and particularly of Jesse Burton Harrison and Burton Norvell Harrisonby Fairfax Harrison; Francis Burton Harrison

    Harrison, Fairfax   Harrison, Francis Burton  

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  • Del Derecho de la Guerra y de la Paz.by Hugo Grocio; Jaime Torrubiano Ripoll;De Jure Belli ac Pacis Libri Tres.by Hugo Grotius; Francis W. Kelsey; Arthur E. R. Boak; Harry A. Sanders; Jesse S. Reeves; Herbert F. Wright; James Brown Scott

    Review by: C. Van Vollenhoven  

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  • Del Derecho de la Guerra y de la Paz.by Hugo Grocio; Jaime Torrubiano Ripoll;De Jure Belli ac Pacis Libri Tres.by Hugo Grotius; Francis W. Kelsey; Arthur E. R. Boak; Harry A. Sanders; Jesse S. Reeves; Herbert F. Wright; James Brown Scott

    Review by: C. Van Vollenhoven  

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