Last data update: Nov 04, 2024. (Total: 48056 publications since 2009)
Records 1-7 (of 7 Records) |
Query Trace: Alston B[original query] |
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Interlaboratory comparison of a multiplex immunoassay that measures human serum IgG antibodies against six-group B streptococcus polysaccharides
Le Doare K , Gaylord MA , Anderson AS , Andrews N , Baker CJ , Bolcen S , Felek A , Giardina PC , Grube CD , Hall T , Hallis B , Izu A , Madhi SA , Maniatis P , Matheson M , Mawas F , McKeen A , Rhodes J , Alston B , Patel P , Schrag S , Simon R , Tan CY , Taylor S , Kwatra G , Gorringe A . Hum Vaccin Immunother 2024 20 (1) 2330138 Measurement of IgG antibodies against group B streptococcus (GBS) capsular polysaccharide (CPS) by use of a standardized and internationally accepted multiplex immunoassay is important for the evaluation of candidate maternal GBS vaccines in order to compare results across studies. A standardized assay is also required if serocorrelates of protection against invasive GBS disease are to be established in infant sera for the six predominant GBS serotypes since it would permit the comparison of results across the six serotypes. We undertook an interlaboratory study across five laboratories that used standardized assay reagents and protocols with a panel of 44 human sera to measure IgG antibodies against GBS CPS serotypes Ia, Ib, II, III, IV, and V. The within-laboratory intermediate precision, which included factors like the lot of coated beads, laboratory analyst, and day, was generally below 20% relative standard deviation (RSD) for all six serotypes, across all five laboratories. The cross-laboratory reproducibility was < 25% RSD for all six serotypes, which demonstrated the consistency of results across the different laboratories. Additionally, anti-CPS IgG concentrations for the 44-member human serum panel were established. The results of this study showed assay robustness and that the resultant anti-CPS IgG concentrations were reproducible across laboratories for the six GBS CPS serotypes when the standardized assay was used. |
Examination of SARS-CoV-2 serological test results from multiple commercial and laboratory platforms with an in-house serum panel
Lester SN , Stumpf M , Freeman BD , Mills L , Schiffer J , Semenova V , Jia T , Desai R , Browning P , Alston B , Ategbole M , Bolcen S , Chen A , David E , Manitis P , Tatum H , Qin Y , Zellner B , Drobeniuc J , Tejada-Strop A , Chatterjee P , Shrivastava-Ranjan P , Jenks MH , McMullan LK , Flint M , Spiropoulou CF , Niemeyer GP , Werner BJ , Bean CJ , Johnson JA , Hoffmaster AR , Satheshkumar PS , Schuh AJ , Owen SM , Thornburg NJ . Access Microbiol 2024 6 (2) Severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) is a novel human coronavirus that was identified in 2019. SARS-CoV-2 infection results in an acute, severe respiratory disease called coronavirus disease 2019 (COVID-19). The emergence and rapid spread of SARS-CoV-2 has led to a global public health crisis, which continues to affect populations across the globe. Real time reverse transcription polymerase chain reaction (rRT-PCR) is the reference standard test for COVID-19 diagnosis. Serological tests are valuable tools for serosurveillance programs and establishing correlates of protection from disease. This study evaluated the performance of one in-house enzyme linked immunosorbent assay (ELISA) utilizing the pre-fusion stabilized ectodomain of SARS-CoV-2 spike (S), two commercially available chemiluminescence assays Ortho VITROS Immunodiagnostic Products Anti-SARS-CoV-2 Total Reagent Pack and Abbott SARS-CoV-2 IgG assay and one commercially available Surrogate Virus Neutralization Test (sVNT), GenScript USA Inc., cPass SARS-CoV-2 Neutralization Antibody Detection Kit for the detection of SARS-CoV-2 specific antibodies. Using a panel of rRT-PCR confirmed COVID-19 patients' sera and a negative control group as a reference standard, all three immunoassays demonstrated high comparable positivity rates and low discordant rates. All three immunoassays were highly sensitive with estimated sensitivities ranging from 95.4-96.6 %. ROC curve analysis indicated that all three immunoassays had high diagnostic accuracies with area under the curve (AUC) values ranging from 0.9698 to 0.9807. High positive correlation was demonstrated among the conventional microneutralization test (MNT) titers and the sVNT inhibition percent values. Our study indicates that independent evaluations are necessary to optimize the overall utility and the interpretation of the results of serological tests. Overall, we demonstrate that all serological tests evaluated in this study are suitable for the detection of SARS-CoV-2 antibodies. |
Development of a standardized opsonophagocytosis killing assay for group B Streptococcus and assessment in an interlaboratory study
Leung S , Collett CF , Allen L , Lim S , Maniatis P , Bolcen SJ , Alston B , Patel PY , Kwatra G , Hall T , Thomas S , Taylor S , Le Doare K , Gorringe A . Vaccines (Basel) 2023 11 (11) The placental transfer of antibodies that mediate bacterial clearance via phagocytes is likely important for protection against invasive group B Streptococcus (GBS) disease. A robust functional assay is essential to determine the immune correlates of protection and assist vaccine development. Using standard reagents, we developed and optimized an opsonophagocytic killing assay (OPKA) where dilutions of test sera were incubated with bacteria, baby rabbit complement (BRC) and differentiated HL60 cells (dHL60) for 30 min. Following overnight incubation, the surviving bacteria were enumerated and the % bacterial survival was calculated relative to serum-negative controls. A reciprocal 50% killing titer was then assigned. The minimal concentrations of anti-capsular polysaccharide (CPS) IgG required for 50% killing were 1.65-3.70 ng/mL (depending on serotype). Inhibition of killing was observed using sera absorbed with homologous CPS but not heterologous CPS, indicating specificity for anti-CPS IgG. The assay performance was examined in an interlaboratory study using residual sera from CPS-conjugate vaccine trials with international partners in the Group B Streptococcus Assay STandardisatiON (GASTON) Consortium. Strong correlations of reported titers between laboratories were observed: ST-Ia r = 0.88, ST-Ib r = 0.91, ST-II r = 0.91, ST-III r = 0.90 and ST-V r = 0.94. The OPKA is an easily transferable assay with accessible standard reagents and will be a valuable tool to assess GBS-specific antibodies in natural immunity and vaccine studies. |
Priority topics for the Community Preventive Services Task Force, 2020-2025: A data-driven, partner-informed approach
Lansky A , Wethington HR , Mattick K , Chin MH , Alston A , Racine-Parshall J , Minor SL , Cobb J , Hopkins DP . Am J Prev Med 2022 62 (6) e375-e378 INTRODUCTION: The Community Preventive Services Task Force periodically engages in a process to identify priority topics to guide their work. This article described the process and results for selecting priority topics to guide the work of the Community Preventive Services Task Force for the period 2020-2025. METHODS: The Community Preventive Services Task Force started with Healthy People 2020 topics. They solicited input on topics from partner organizations and the public. The Community Preventive Services Task Force considered information on 8 criteria for each topic. They conducted preliminary voting and applied a priori decision rules regarding the voting results. The Community Preventive Services Task Force then engaged in facilitated deliberations and took a final vote. This process occurred October 2019-June 2020. RESULTS: From Healthy People 2020, a total of 37 topics were selected as the starting point. The initial voting and decision rules resulted in 3 topics being determined as priorities. Community Preventive Services Task Force members considered data and information on the criteria to inform their deliberations on an additional 7 topics. A total of 9 topics were selected as the set of priorities for 2020-2025. CONCLUSIONS: Having a process that is routine and data-driven ensures that the selection of priorities is sound. By reviewing priority topics every 5 years, the Community Preventive Services Task Force will continue to provide relevant recommendations on community preventive services to improve the nation's health. |
Familiarity with and use of insufficient evidence findings from the Community Preventive Services Task Force
Alston A , Cotter MM , Klabunde CN , Neilson E . Am J Prev Med 2020 60 (4) e199-e201 The Community Preventive Services Task Force (CPSTF) is an independent, nonfederal panel of experts that uses systematic reviews to develop recommendations about community preventive services and programs to improve population health. The CPSTF issues an insufficient evidence (IE) finding when the evidence is lacking, inconsistent, or has significant methodologic limitations. An IE finding indicates a need for more research.1 The NIH partners with the Centers for Disease Control and Prevention Community Guide Office to support the CPSTF in making evidence-based recommendations and identifying research gaps.2 NIH also collaborates to communicate IE findings and engage researchers and research funders in addressing the evidence gaps. An evaluation was conducted to learn more about the researchers’ and research funders’ familiarity with and use of IE findings, with the aim of improving the way they are communicated. |
Serologic testing of U.S. blood donations to identify SARS-CoV-2-reactive antibodies: December 2019-January 2020.
Basavaraju SV , Patton ME , Grimm K , Rasheed MAU , Lester S , Mills L , Stumpf M , Freeman B , Tamin A , Harcourt J , Schiffer J , Semenova V , Li H , Alston B , Ategbole M , Bolcen S , Boulay D , Browning P , Cronin L , David E , Desai R , Epperson M , Gorantla Y , Jia T , Maniatis P , Moss K , Ortiz K , Park SH , Patel P , Qin Y , Steward-Clark E , Tatum H , Vogan A , Zellner B , Drobeniuc J , Sapiano MRP , Havers F , Reed C , Gerber S , Thornburg NJ , Stramer SL . Clin Infect Dis 2020 72 (12) e1004-e1009 BACKGROUND: SARS-CoV-2, the virus that causes COVID-19 disease, was first identified in Wuhan, China in December 2019, with subsequent worldwide spread. The first U.S. cases were identified in January 2020. METHODS: To determine if SARS-CoV-2 reactive antibodies were present in sera prior to the first identified case in the U.S. on January 19, 2020, residual archived samples from 7,389 routine blood donations collected by the American Red Cross from December 13, 2019 to January 17, 2020, from donors resident in nine states (California, Connecticut, Iowa, Massachusetts, Michigan, Oregon, Rhode Island, Washington, and Wisconsin) were tested at CDC for anti-SARS-CoV-2 antibodies. Specimens reactive by pan-immunoglobulin (pan Ig) enzyme linked immunosorbent assay (ELISA) against the full spike protein were tested by IgG and IgM ELISAs, microneutralization test, Ortho total Ig S1 ELISA, and receptor binding domain / Ace2 blocking activity assay. RESULTS: Of the 7,389 samples, 106 were reactive by pan Ig. Of these 106 specimens, 90 were available for further testing. Eighty four of 90 had neutralizing activity, 1 had S1 binding activity, and 1 had receptor binding domain / Ace2 blocking activity >50%, suggesting the presence of anti-SARS-CoV-2-reactive antibodies. Donations with reactivity occurred in all nine states. CONCLUSIONS: These findings suggest that SARS-CoV-2 may have been introduced into the United States prior to January 19, 2020. |
Sources of support for studies that inform recommendations of the Community Preventive Services Task Force
Neilson E , Villani J , Mercer SL , Tilley DL , Vincent I , Alston A , Klabunde CN . Public Health Rep 2020 135 (6) 813-822 OBJECTIVES: The Community Preventive Services Task Force (CPSTF) makes evidence-based recommendations about preventive services, programs, and policies in community settings to improve public health. CPSTF recommendations are based on systematic evidence reviews. This study examined the sponsors (ie, sources of financial, material, or intellectual support) for publications included in systematic reviews used by the CPSTF to make recommendations during a 9-year period. METHODS: We examined systematic evidence reviews (effectiveness reviews and economic reviews) for CPSTF findings issued from January 1, 2010, through December 31, 2018. We assessed study publications used in these reviews for sources of support; we classified sources as government, nonprofit, industry, or no identified support. We also identified country of origin for each sponsor and the most frequently mentioned sponsors. RESULTS: The CPSTF issued findings based on 144 systematic reviews (106 effectiveness reviews and 38 economic reviews). These reviews included 3846 publications: 3363 publications in effectiveness reviews and 483 publications in economic reviews. Government agencies supported 57.1% (n = 1919) of publications in effectiveness reviews and 59.2% (n = 286) in economic reviews. More than 1500 study sponsors from 36 countries provided support. The National Institutes of Health was the leading sponsor for effectiveness reviews (21.3%; 718 of 3363) and economic reviews (16.2%; 78 of 480), followed by the Centers for Disease Control and Prevention (7.0%; 234 of 3363 effectiveness reviews and 14.8%; 71 of 480 economic reviews). CONCLUSIONS: The evidence base used by the CPSTF was supported by an array of sponsors, with government agencies providing the most support. Study findings highlight the need for sponsorship transparency and the role of government as a leading supporter of studies that underpin CPSTF recommendations for improving public health. |
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