Last data update: Nov 04, 2024. (Total: 48056 publications since 2009)
Records 1-17 (of 17 Records) |
Query Trace: Petway ME[original query] |
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Rapid Development of Neutralizing and Diagnostic SARS-COV-2 Mouse Monoclonal Antibodies (preprint)
Chapman AP , Tang X , Lee JR , Chida A , Mercer K , Wharton RE , Kainulainen M , Harcourt JL , Martines RB , Schroeder M , Zhao L , Bryksin A , Zhou B , Bergeron E , Bollweg BC , Tamin A , Thornburg N , Wentworth DE , Petway D , Bagarozzi DA Jr , Finn MG , Goldstein JM . bioRxiv 2020 2020.10.13.338095 The need for high-affinity, SARS-CoV-2-specific monoclonal antibodies (mAbs) is critical in the face of the global COVID-19 pandemic, as such reagents can have important diagnostic, research, and therapeutic applications. Of greatest interest is the ~300 amino acid receptor binding domain (RBD) within the S1 subunit of the spike protein because of its key interaction with the human angiotensin converting enzyme 2 (hACE2) receptor present on many cell types, especially lung epithelial cells. We report here the development and functional characterization of 29 nanomolar-affinity mouse SARS-CoV-2 mAbs created by an accelerated immunization and hybridoma screening process. Differing functions, including binding of diverse protein epitopes, viral neutralization, impact on RBD-hACE2 binding, and immunohistochemical staining of infected lung tissue, were correlated with variable gene usage and sequence.Competing Interest StatementThe authors have declared no competing interest. |
High-throughput quantitation of SARS-CoV-2 antibodies in a single-dilution homogeneous assay (preprint)
Kainulainen MH , Bergeron E , Chatterjee P , Chapman AP , Lee J , Chida A , Tang X , Wharton RE , Mercer KB , Petway M , Jenks HM , Flietstra TD , Schuh AJ , Satheshkumar PS , Chaitram JM , Owen SM , Finn MG , Goldstein JM , Montgomery JM , Spiropoulou CF . medRxiv 2020 2020.09.16.20195446 SARS-CoV-2 emerged in late 2019 and has since spread around the world, causing a pandemic of the respiratory disease COVID-19. Detecting antibodies against the virus is an essential tool for tracking infections and developing vaccines. Such tests, primarily utilizing the enzyme-linked immunosorbent assay (ELISA) principle, can be either qualitative (reporting positive/negative results) or quantitative (reporting a value representing the quantity of specific antibodies). Quantitation is vital for determining stability or decline of antibody titers in convalescence, efficacy of different vaccination regimens, and detection of asymptomatic infections. Quantitation typically requires two-step ELISA testing, in which samples are first screened in a qualitative assay and positive samples are subsequently analyzed as a dilution series. To overcome the throughput limitations of this approach, we developed a simpler and faster system that is highly automatable and achieves quantitation in a single-dilution screening format with sensitivity and specificity comparable to those of ELISA.One sentence summary Protein complementation enables mix-and-read SARS-CoV-2 serology that rivals sensitivity and specificity of ELISA but excels in throughput and quantitation.Competing Interest StatementThe authors have declared no competing interest.Funding StatementThis research was funded by the Centers for Disease Control and Prevention.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:Residual specimen materials were used for diagnostics development under a protocol that was reviewed and approved by the CDC Institutional Review Board (See 45 C.F.R. part 46; 21 C.F.R. part 56)All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesNo external data links |
SARS-CoV-2 infection risk among vaccinated and unvaccinated household members during the Alpha variant surge - Denver, Colorado, and San Diego, California, January-April 2021.
McCormick DW , Konkle SL , Magleby R , Chakrabarti AK , Cherney B , Lindell K , Namageyo-Funa A , Visser S , Soto RA , Donnelly MAP , Stringer G , Austin B , Beatty ME , Stous S , Albanese BA , Chu VT , Chuey M , Dietrich EA , Drobeniuc J , Folster JM , Killerby ME , Lehman JA , McDonald EC , Ruffin J , Schwartz NG , Sheldon SW , Sleweon S , Thornburg NJ , Hughes LJ , Petway M , Tong S , Whaley MJ , Kirking HL , Tate JE , Hsu CH , Matanock A . Vaccine 2022 40 (33) 4845-4855 BACKGROUND: COVID-19 vaccination reduces SARS-CoV-2 infection and transmission. However, evidence is emerging on the degree of protection across variants and in high-transmission settings. To better understand the protection afforded by vaccination specifically in a high-transmission setting, we examined household transmission of SARS-CoV-2 during a period of high community incidence with predominant SARS-CoV-2 B.1.1.7 (Alpha) variant, among vaccinated and unvaccinated contacts. METHODS: We conducted a household transmission investigation in San Diego County, California, and Denver, Colorado, during January-April 2021. Households were enrolled if they had at least one person with documented SARS-CoV-2 infection. We collected nasopharyngeal swabs, blood, demographic information, and vaccination history from all consenting household members. We compared infection risks (IRs), RT-PCR cycle threshold values, SARS-CoV-2 culture results, and antibody statuses among vaccinated and unvaccinated household contacts. RESULTS: We enrolled 493 individuals from 138 households. The SARS-CoV-2 variant was identified from 121/138 households (88%). The most common variants were Alpha (75/121, 62%) and Epsilon (19/121, 16%). There were no households with discordant lineages among household members. One fully vaccinated secondary case was symptomatic (13%); the other 5 were asymptomatic (87%). Among unvaccinated secondary cases, 105/108 (97%) were symptomatic. Among 127 households with a single primary case, the IR for household contacts was 45% (146/322; 95% Confidence Interval [CI] 40-51%). The observed IR was higher in unvaccinated (130/257, 49%, 95% CI 45-57%) than fully vaccinated contacts (6/26, 23%, 95% CI 11-42%). A lower proportion of households with a fully vaccinated primary case had secondary cases (1/5, 20%) than households with an unvaccinated primary case (66/108, 62%). CONCLUSIONS: Although SARS-CoV-2 infections in vaccinated household contacts were reported in this high transmission setting, full vaccination protected against SARS-CoV-2 infection. These findings further support the protective effect of COVID-19 vaccination and highlight the need for ongoing vaccination among eligible persons. |
Household Transmission and Symptomology of SARS-CoV-2 Alpha Variant Among Children-California and Colorado, 2021.
Waltenburg MA , Whaley MJ , Chancey RJ , Donnelly MAP , Chuey MR , Soto R , Schwartz NG , Chu VT , Sleweon S , McCormick DW , Uehara A , Retchless AC , Tong S , Folster JM , Petway M , Thornburg NJ , Drobeniuc J , Austin B , Hudziec MM , Stringer G , Albanese BA , Totten SE , Matzinger SR , Staples JE , Killerby ME , Hughes LJ , Matanock A , Beatty M , Tate JE , Kirking HL , Hsu CH . J Pediatr 2022 247 29-37 e7 OBJECTIVE: To assess the household secondary infection risk (SIR) of B.1.1.7 (Alpha) and non-Alpha lineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children. STUDY DESIGN: During January-April 2021, we prospectively followed households with a SARS-CoV-2 infection. We collected questionnaires, serial nasopharyngeal swabs for RT-PCR testing and whole genome sequencing, and serial blood samples for serology testing. We calculated SIRs by primary case age (pediatric vs. adult), household contact age, and viral lineage. We evaluated risk factors associated with transmission and described symptom profiles among children. RESULTS: Among 36 households with pediatric primary cases, 21 (58%) had secondary infections. Among 91 households with adult primary cases, 51 (56%) had secondary infections. SIRs among pediatric and adult primary cases were 45% and 54%, respectively (OR: 0.79 [95% CI 0.41-1.54]). SIRs among pediatric primary cases with Alpha and non-Alpha lineage were 55% and 46%, respectively (OR: 1.52 [CI 0.51-4.53]). SIRs among pediatric and adult household contacts were 55% and 49%, respectively (OR: 1.01 [CI 0.68-1.50]). Among pediatric contacts, no significant differences in odds of acquiring infection by demographic or household characteristics were observed. CONCLUSIONS: Household transmission of SARS-CoV-2 from children and adult primary cases to household members was frequent. Risk of secondary infection was similar among child and adult household contacts. Among children, household transmission of SARS-CoV-2 and risk of secondary infection was not influenced by lineage. Continued mitigation strategies (e.g., masking, physical distancing, vaccination) are needed to protect at-risk groups regardless of virus lineage circulating in communities. |
Household transmission of SARS-CoV-2 Alpha variant - United States, 2021.
Donnelly MAP , Chuey MR , Soto R , Schwartz NG , Chu VT , Konkle SL , Sleweon S , Ruffin J , Haberling DL , Guagliardo SAJ , Stoddard RA , Anderson RD , Morgan CN , Rossetti R , McCormick DW , Magleby R , Sheldon SW , Dietrich EA , Uehara A , Retchless AC , Tong S , Folster JM , Drobeniuc J , Petway ME , Austin B , Stous S , McDonald E , Jain S , Hudziec MM , Stringer G , Albanese BA , Totten SE , Staples JE , Killerby ME , Hughes L , Matanock A , Beatty M , Tate JE , Kirking HL , Hsu CH . Clin Infect Dis 2022 75 (1) e122-e132 BACKGROUND: In Spring 2021, SARS-CoV-2 B.1.1.7 (Alpha) became the predominant variant in the U.S. Research suggests that Alpha has increased transmissibility compared to non-Alpha lineages. We estimated household secondary infection risk (SIR), assessed characteristics associated with transmission, and compared symptoms of persons with Alpha and non-Alpha infections. METHODS: We followed households with SARS-CoV-2 infection for two weeks in San Diego County and metropolitan Denver, January to April 2021. We collected epidemiologic information and biospecimens for serology, RT-PCR, and whole genome sequencing. We stratified SIR and symptoms by lineage, and identified characteristics associated with transmission using Generalized Estimating Equations. RESULTS: We investigated 127 households with 322 household contacts; 72 households (56.7%) had member(s) with secondary infections. SIRs were not significantly higher for Alpha (61.0% [95% confidence interval (CI) 52.4-69.0%]) than non-Alpha (55.6% [CI 44.7-65.9%], P = 0.49). In households with Alpha, persons who identified as Asian or Hispanic/Latino had significantly higher SIRs than those who identified as White (P = 0.01 and 0.03, respectively). Close contact (e.g., kissing, hugging) with primary cases was associated with increased transmission for all lineages. Persons with Alpha infection were more likely to report constitutional symptoms than persons with non-Alpha (86.9% vs. 76.8%, P = 0.05). CONCLUSIONS: Household SIRs were similar for Alpha and non-Alpha. Comparable SIRs may be due to saturation of transmission risk in households owing to extensive close contact, or true lack of difference in transmission rates. Avoiding close contact within households may reduce SARS-CoV-2 transmission for all lineages among household members. |
Analysis of the initial lot of the CDC 2019-Novel Coronavirus (2019-nCoV) real-time RT-PCR diagnostic panel.
Lee JS , Goldstein JM , Moon JL , Herzegh O , Bagarozzi DAJr , Oberste MS , Hughes H , Bedi K , Gerard D , Cameron B , Benton C , Chida A , Ahmad A , Petway DJJr , Tang X , Sulaiman N , Teklu D , Batra D , Howard D , Sheth M , Kuhnert W , Bialek SR , Hutson CL , Pohl J , Carroll DS . PLoS One 2021 16 (12) e0260487 At the start of the COVID-19 pandemic, the Centers for Disease Control and Prevention (CDC) designed, manufactured, and distributed the CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel for SARS-CoV-2 detection. The diagnostic panel targeted three viral nucleocapsid gene loci (N1, N2, and N3 primers and probes) to maximize sensitivity and to provide redundancy for virus detection if mutations occurred. After the first distribution of the diagnostic panel, state public health laboratories reported fluorescent signal in the absence of viral template (false-positive reactivity) for the N3 component and to a lesser extent for N1. This report describes the findings of an internal investigation conducted by the CDC to identify the cause(s) of the N1 and N3 false-positive reactivity. For N1, results demonstrate that contamination with a synthetic template, that occurred while the "bulk" manufactured materials were located in a research lab for quality assessment, was the cause of false reactivity in the first lot. Base pairing between the 3' end of the N3 probe and the 3' end of the N3 reverse primer led to amplification of duplex and larger molecules resulting in false reactivity in the N3 assay component. We conclude that flaws in both assay design and handling of the "bulk" material, caused the problems with the first lot of the 2019-nCoV Real-Time RT-PCR Diagnostic Panel. In addition, within this study, we found that the age of the examined diagnostic panel reagents increases the frequency of false positive results for N3. We discuss these findings in the context of improvements to quality control, quality assurance, and assay validation practices that have since been improved at the CDC. |
Development and Evaluation of a TaqMan Real-Time PCR Assay for the Rapid Detection of Cross-Contamination of RD (Human) and L20B (Mouse) Cell Lines Used in Poliovirus Surveillance.
Ahmad A , Lee JR , Metz JM , Tang X , Lin SC , Bagarozzi DAJr , Petway D , Herzegh O . J Virol Methods 2021 300 114354 BACKGROUND: The cross-contamination of cell lines in culture is a persistent problem. Genetically modified L20B (Mouse) and RD (Human Rhabdomyosarcoma) cell lines are commonly used in poliovirus research, surveillance, and diagnostics. Cross-contamination between these cell lines leads to unreproducible results and unreliable surveillance data, negatively affecting public health. The gold standard method for cell authentication is Short Tandem Repeats analysis, which is time-consuming and expensive. The disadvantage of STR is limited detection of interspecies contamination. METHODS: This assay targets the mitochondrial cytochrome c oxidase subunit I (MTCO1) gene, a highly conserved and emergent DNA barcode region for detection of cross-contamination in RD and L20B cell lines. The MagNA Pure Compact instrument and ABI 7500 Fast Dx Real-time PCR systems were used for DNA extraction and to perform real-time PCR respectively. RESULTS: The newly developed assay is very sensitive with a limit of detection of 100 RD cells/1 million L20B/mL. The amplification efficiency and R(2)-value were 102.26% and 0.9969 respectively. We evaluated specificity of the assay with five human and four mouse cell lines, as well as monkey and rat cell lines. The assay showed no cross-reactivity with genomic DNA from human, mouse, rat, or monkey cell lines. The analytical sensitivity was also evaluated by spiking varying amounts of RD cells (0.001% - 10%) into L20B cells. There was no difference in C(T) values when running single-plex or duplex PCR reactions with similar experimental conditions. CONCLUSIONS: We have developed and validated a TaqMan real-time PCR assay, a sensitive method for the detection of cross-contamination of RD and L20B cell lines. |
Performance characteristics of the Abbott BinaxNOW SARS-CoV-2 antigen test in comparison to real-time RT-PCR and viral culture in community testing sites during November 2020.
Almendares O , Prince-Guerra JL , Nolen LD , Gunn JKL , Dale AP , Buono SA , Deutsch-Feldman M , Suppiah S , Hao L , Zeng Y , Stevens VA , Knipe K , Pompey J , Atherstone C , Bui DP , Powell T , Tamin A , Harcourt JL , Petway M , Bohannon C , Folster JM , MacNeil A , Salerno R , Kuhnert-Tallman W , Tate JE , Thornburg N , Kirking HL , Villanueva JM , Rose DA , Neatherlin JC , Anderson M , Rota PA , Honein MA , Bower WA . J Clin Microbiol 2021 60 (1) Jcm0174221 Point-of-care antigen tests are an important tool for SARS-CoV-2 detection. Antigen tests are less sensitive than real-time reverse-transcriptase PCR (rRT-PCR). Data on the performance of the BinaxNOW antigen test compared to rRT-PCR and viral culture by symptom and known exposure status, timing during disease or exposure period and demographic variables are limited. During November 3(rd)-17(th), 2020, we collected paired upper respiratory swab specimens to test for SARS-CoV-2 by rRT-PCR and Abbott BinaxNOW (BinaxNOW) antigen test at two community testing sites in Pima County, Arizona. We administered a questionnaire to capture symptoms, known exposure status and previous SARS-CoV-2 test results. Specimens positive by either test were analyzed by viral culture. Previously we showed overall BinaxNOW sensitivity was 52.5%. Here we showed BinaxNOW sensitivity increased to 65.7% among currently symptomatic individuals reporting a known exposure. BinaxNOW sensitivity was lower among participants with a known exposure and previously symptomatic (32.4%) or never symptomatic (47.1%) within 14 days of testing. Sensitivity was 71.1% in participants within a week of symptom onset. In participants with a known exposure, sensitivity was highest 8-10 days post-exposure (75%). The positive predictive value for recovery of virus in cell culture was 56.7% for BinaxNOW-positive and 35.4% for rRT-PCR-positive specimens. Result reporting time was 2.5 hours for BinaxNOW and 26 hours for rRT-PCR. Point-of-care antigen tests have a shorter turn-around time compared to laboratory-based nucleic acid amplification tests, which allows for more rapid identification of infected individuals. Antigen test sensitivity limitations are important to consider when developing a testing program. |
Point-of-Care Antigen Test for SARS-CoV-2 in Asymptomatic College Students.
Tinker SC , Szablewski CM , Litvintseva AP , Folster J , Shewmaker PL , Medrzycki M , Bowen MD , Bohannon C , Bagarozzi D Jr , Petway M , Rota PA , Kuhnert-Tallman W , Thornburg N , Prince-Guerra JL , Barrios LC , Tamin A , Harcourt JL , Honein MA . Emerg Infect Dis 2021 27 (10) 2662-2665 We used the BinaxNOW COVID-19 Ag Card to screen 1,540 asymptomatic college students for severe acute respiratory syndrome coronavirus 2 in a low-prevalence setting. Compared with reverse transcription PCR, BinaxNOW showed 20% overall sensitivity; among participants with culturable virus, sensitivity was 60%. BinaxNOW provides point-of-care screening but misses many infections. |
High-throughput quantitation of SARS-CoV-2 antibodies in a single-dilution homogeneous assay.
Kainulainen MH , Bergeron E , Chatterjee P , Chapman AP , Lee J , Chida A , Tang X , Wharton RE , Mercer KB , Petway M , Jenks HM , Flietstra TD , Schuh AJ , Satheshkumar PS , Chaitram JM , Owen SM , McMullan LK , Flint M , Finn MG , Goldstein JM , Montgomery JM , Spiropoulou CF . Sci Rep 2021 11 (1) 12330 SARS-CoV-2 emerged in late 2019 and has since spread around the world, causing a pandemic of the respiratory disease COVID-19. Detecting antibodies against the virus is an essential tool for tracking infections and developing vaccines. Such tests, primarily utilizing the enzyme-linked immunosorbent assay (ELISA) principle, can be either qualitative (reporting positive/negative results) or quantitative (reporting a value representing the quantity of specific antibodies). Quantitation is vital for determining stability or decline of antibody titers in convalescence, efficacy of different vaccination regimens, and detection of asymptomatic infections. Quantitation typically requires two-step ELISA testing, in which samples are first screened in a qualitative assay and positive samples are subsequently analyzed as a dilution series. To overcome the throughput limitations of this approach, we developed a simpler and faster system that is highly automatable and achieves quantitation in a single-dilution screening format with sensitivity and specificity comparable to those of ELISA. |
Rapid development of neutralizing and diagnostic SARS-COV-2 mouse monoclonal antibodies.
Chapman AP , Tang X , Lee JR , Chida A , Mercer K , Wharton RE , Kainulainen M , Harcourt JL , Martines RB , Schroeder M , Zhao L , Bryksin A , Zhou B , Bergeron E , Bollweg BC , Tamin A , Thornburg N , Wentworth DE , Petway D , Bagarozzi DA Jr , Finn MG , Goldstein JM . Sci Rep 2021 11 (1) 9682 The need for high-affinity, SARS-CoV-2-specific monoclonal antibodies (mAbs) is critical in the face of the global COVID-19 pandemic, as such reagents can have important diagnostic, research, and therapeutic applications. Of greatest interest is the ~ 300 amino acid receptor binding domain (RBD) within the S1 subunit of the spike protein because of its key interaction with the human angiotensin converting enzyme 2 (hACE2) receptor present on many cell types, especially lung epithelial cells. We report here the development and functional characterization of 29 nM-affinity mouse SARS-CoV-2 mAbs created by an accelerated immunization and hybridoma screening process. Differing functions, including binding of diverse protein epitopes, viral neutralization, impact on RBD-hACE2 binding, and immunohistochemical staining of infected lung tissue, were correlated with variable gene usage and sequence. |
Evaluation of Abbott BinaxNOW Rapid Antigen Test for SARS-CoV-2 Infection at Two Community-Based Testing Sites - Pima County, Arizona, November 3-17, 2020.
Prince-Guerra JL , Almendares O , Nolen LD , Gunn JKL , Dale AP , Buono SA , Deutsch-Feldman M , Suppiah S , Hao L , Zeng Y , Stevens VA , Knipe K , Pompey J , Atherstone C , Bui DP , Powell T , Tamin A , Harcourt JL , Shewmaker PL , Medrzycki M , Wong P , Jain S , Tejada-Strop A , Rogers S , Emery B , Wang H , Petway M , Bohannon C , Folster JM , MacNeil A , Salerno R , Kuhnert-Tallman W , Tate JE , Thornburg NJ , Kirking HL , Sheiban K , Kudrna J , Cullen T , Komatsu KK , Villanueva JM , Rose DA , Neatherlin JC , Anderson M , Rota PA , Honein MA , Bower WA . MMWR Morb Mortal Wkly Rep 2021 70 (3) 100-105 Rapid antigen tests, such as the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW), offer results more rapidly (approximately 15-30 minutes) and at a lower cost than do highly sensitive nucleic acid amplification tests (NAATs) (1). Rapid antigen tests have received Food and Drug Administration (FDA) Emergency Use Authorization (EUA) for use in symptomatic persons (2), but data are lacking on test performance in asymptomatic persons to inform expanded screening testing to rapidly identify and isolate infected persons (3). To evaluate the performance of the BinaxNOW rapid antigen test, it was used along with real-time reverse transcription-polymerase chain reaction (RT-PCR) testing to analyze 3,419 paired specimens collected from persons aged ≥10 years at two community testing sites in Pima County, Arizona, during November 3-17, 2020. Viral culture was performed on 274 of 303 residual real-time RT-PCR specimens with positive results by either test (29 were not available for culture). Compared with real-time RT-PCR testing, the BinaxNOW antigen test had a sensitivity of 64.2% for specimens from symptomatic persons and 35.8% for specimens from asymptomatic persons, with near 100% specificity in specimens from both groups. Virus was cultured from 96 of 274 (35.0%) specimens, including 85 (57.8%) of 147 with concordant antigen and real-time RT-PCR positive results, 11 (8.9%) of 124 with false-negative antigen test results, and none of three with false-positive antigen test results. Among specimens positive for viral culture, sensitivity was 92.6% for symptomatic and 78.6% for asymptomatic individuals. When the pretest probability for receiving positive test results for SARS-CoV-2 is elevated (e.g., in symptomatic persons or in persons with a known COVID-19 exposure), a negative antigen test result should be confirmed by NAAT (1). Despite a lower sensitivity to detect infection, rapid antigen tests can be an important tool for screening because of their quick turnaround time, lower costs and resource needs, high specificity, and high positive predictive value (PPV) in settings of high pretest probability. The faster turnaround time of the antigen test can help limit transmission by more rapidly identifying infectious persons for isolation, particularly when used as a component of serial testing strategies. |
Comparison of Zika virus inactivation methods for reagent production and disinfection methods
Chida AS , Goldstein JM , Lee J , Tang X , Bedi K , Herzegh O , Moon JL , Petway D , Bagarozzi DAJr , Hughes LJ . J Virol Methods 2020 287 114004 Zika virus (ZIKV) infection remains a public health concern necessitating demand for long-term virus production for diagnostic assays and R&D activities. Inactivated virus constitutes an important component of the Trioplex rRT-PCR assay and serological IgM assay (MAC-ELISA). The aim of our study is to establish standard methods of ZIKV inactivation while maintaining antigenicity and RNA integrity. We tested viral supernatants by four different inactivation methods: 1. Heat inactivation at 56 °C and 60 °C; 2. Gamma-Irradiation; 3. Chemical inactivation by Beta-propiolactone (BPL) and 4. Fast-acting commercial disinfecting agents. Effectivity was measured by cytopathic effect (CPE) and plaque assay. RNA stability and antigenicity were measured by RT-PCR and MAC-ELISA, respectively. Results: Heat inactivation: Low titer samples, incubated at 56 °C for 2 hrs, showed neither CPE or plaques compared to high titer supernatants that required 2.5 hrs. Inactivation occurred at 60 °C for 60 min with all virus titers. Gamma irradiation: Samples irradiated at ≥3 Mrad for low virus concentrations and ≥5Mrad for high virus titer completely inactivated virus. Chemical Inactivation: Neither CPE nor plaques were observed with ≥0.045% BPL inactivation of ZIKV. Disinfectant: Treatment of viral supernatants with Micro-Chem Plus(TM), inactivated virus in 2 min, whereas, Ethanol (70%) and STERIS Coverage® Spray TB inactivated the virus in 5 min. |
The effects of gamma irradiation on chemical biomarker recovery from mixed chemical/biological threat exposure specimens
Isenberg SL , Carter MD , Moon JL , Laughlin S , Petway M , Mojica MA , Rood JE , Gursky AK , Sheppard CI , Bagarozzi DA , Pirkle JL , Johnson RC . J Appl Lab Med 2020 5 (2) 273-280 BACKGROUND: Irradiative sterilization of clinical specimens prior to chemical laboratory testing provides a way to not only sterilize pathogens and ensure laboratorian safety but also preserve sample volume and maintain compatibility with quantitative chemical diagnostic protocols. Since the compatibility of clinical biomarkers with gamma irradiation is not well characterized, a subset of diagnostic biomarkers ranging in molecular size, concentration, and clinical matrix was analyzed to determine recovery following gamma irradiation. METHODS: Sample irradiation of previously characterized quality control materials (QCs) at 5 Mrad was carried out at the Gamma Cell Irradiation Facility at the Centers for Disease Control and Prevention (CDC) in Atlanta, GA. Following irradiation, the QCs were analyzed alongside non-irradiated QCs to determine analyte recovery between dosed and control samples. RESULTS: Biomarkers for exposure to abrin, ricin, and organophosphorus nerve agents (OPNAs) were analyzed for their stability following gamma irradiation. The diagnostic biomarkers included adducts to butyrylcholinesterase, abrine, and ricinine, respectively, and were recovered at over 90% of their initial concentration. CONCLUSIONS: The results from this pilot study support the implementation of an irradiative sterilization protocol for possible mixed-exposure samples containing both chemical and biological threat agents (mixed CBTs). Furthermore, irradiative sterilization significantly reduces a laboratorian's risk of infection from exposure to an infectious agent without compromising chemical diagnostic testing integrity, particularly for diagnostic assays in which the chemical analyte has been shown to be fully conserved following a 5 Mrad irradiative dose. |
Partnerships involved in public health testing for Zika virus in Florida, 2016
Heberlein-Larson L , Gillis LD , Morrison A , Scott B , Cook M , Cannons A , Quaye E , White S , Cone M , Mock V , Schiffer J , Lonsway D , Petway M , Otis A , Stanek D , Hamilton J , Crowe S . Public Health Rep 2019 134 43s-52s The emergence of Zika virus in the Americas in 2015 and its association with birth defects and other adverse health outcomes triggered an unprecedented public health response and a demand for testing. In 2016, when Florida exceeded state public health laboratory capacity for diagnostic testing, the state formed partnerships with federal and commercial laboratories. Eighty-two percent of the testing (n = 33 802 of 41 008 specimens) by the laboratory partners, including Florida's Bureau of Public Health Laboratories (BPHL; n = 13 074), a commercial laboratory (n = 19 214), and the Centers for Disease Control and Prevention (CDC; n = 1514), occurred from July through November 2016, encompassing the peak period of local transmission. These partnerships allowed BPHL to maintain acceptable test turnaround times of 1 to 4 days for nucleic acid testing and 3 to 7 days for serologic testing. Lessons learned from this response to inform future outbreaks included the need for early planning to establish outside partnerships, adding specimen triage strategies to surge plans, and integrating state and CDC information systems. |
Implementation of the US Department of Health and Human Services Zika Specimen Repository and Its Effect on Zika Diagnostic Test Development, 2016.
Petway M , Anderson L , Humes R , Sincock S , Kuhnert-Tallman W , Miller J , Wallace RL . Public Health Rep 2019 134 53s-57s This study describes the efforts and outcomes associated with the establishment of a clinical sample repository during the 2016 Zika virus epidemic. To overcome the challenge of limited access to clinical samples to support diagnostic test development, multiple US Department of Health and Human Services (HHS) agencies formed a partnership to create the HHS Zika Specimen Repository. In 2016-2017, the Biomedical Advanced Research and Development Authority and the Centers for Disease Control and Prevention collected patient specimens (4420 convalescent sera aliquots from 100 donors and 7171 plasma aliquots from 239 donors), confirmed Zika virus test results, assembled 1 panel for molecular testing (n = 25 sets) and 7 panels for serologic testing (n = 92), and distributed the panels to test developers. We manufactured 8 test panels and distributed 74 sets of panels to 32 commercial companies, public health partners, and research institutions. Manufacturers used these panels to generate data that supported 14 US Food and Drug Administration (FDA) emergency use authorizations and 1 FDA approval. To develop a repository that can respond immediately to future disease outbreaks, we recommend that organizations pre-position procedures, resources, and partnerships to optimize each partner's contribution. |
A high-throughput and rapid method for accurate identification of emerging multidrug-resistant Candida auris.
Ahmad A , Spencer JE , Lockhart SR , Singleton S , Petway DJ , Bagarozzi DAJr , Herzegh OT . Mycoses 2019 62 (6) 513-518 Candida auris is an emerging multidrug-resistant yeast associated with invasive infection in healthcare settings. Recently, C. auris cases in the US have been detected in 11 states with the majority of cases in New York, New Jersey, and Illinois. Rapid and accurate identification of C. auris is critical for patient care and the implementation of public health measures to control the spread of infection. Our aim was to develop and validate a rapid DNA extraction method using the Roche MagNA Pure 96 instrument and a TaqMan real-time PCR assay for reliable, high throughput identification of C. auris. We evaluated 247 patient dermal swab samples previously analyzed by culture/MALDI-TOF. The diagnostic sensitivity and specificity were 93.6% and 97.2%, respectively. The assay was highly reproducible with a detection limit of 1 C. auris CFU/10muL. A ROC curve analysis of the real-time PCR data showed an area of 0.982 under the curve, with a CT cutoff value of </=37.0. The turnaround time from DNA extraction to real-time PCR results was approximately 200 samples/day. In conclusion, we successfully validated a rapid and high throughput method for accurate and reproducible identification of C. auris with a significantly reduced turnaround time compared to culture/MALDI-TOF based methods. This article is protected by copyright. All rights reserved. |
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