Comparison of the Digene HC2 assay and the Roche AMPLICOR human papillomavirus (HPV) test for detection of high-risk HPV genotypes in cervical samples

Many different methods with different sensitivity and specificity have been proposed to detect the presence of high-risk human papillomavirus (HR HPV) in cervical samples. The HC2 is one of the most widely used. Recently, a new standardized PCR-based method, the AMPLICOR HPV test, has been introduced. Both assays recognize the same 13 HR HPV genotypes. The performances of these two commercially available assays were compared in 167 consecutive women (for a total of 168 samples) who presented at the Colposcopy Clinic either for a follow-up or for a diagnostic visit. Concordant results were found in 140/168 cervical samples (overall agreement, 83%; Cohen's kappa = 0.63). Twenty-eight samples gave discordant results: 20 were positive with the AMPLICOR HPV test and negative with the HC2 assay, and 8 were negative with the AMPLICOR HPV test and positive with the HC2 assay. The genotyping showed that no HR HPV was detected in the 8 HC2 assay-positive AMPLICOR HPV test-negative samples, while in 8/20 AMPLICOR HPV test-positive HC2 assay-negative samples, an HR HPV genotype was found. The AMPLICOR HPV test scored positive in a significantly higher percentage of subjects with normal Pap smears. All 7 cervical intraepithelial neoplasia grade 3 patients scored positive with the AMPLICOR HPV test, while 2 of them scored negative with HC2. Both tests had positive results in the only patient with squamous cell carcinoma. In conclusion, this study shows that the HC2 assay and the AMPLICOR HPV test give comparable results, with both being suitable for routine use. The differences noted in some cases may suggest a different optimal clinical use.     

Comparison of the Digene Hybrid Capture 2 assay and Roche AMPLICOR and LINEAR ARRAY human papillomavirus (HPV) tests in detecting high-risk HPV genotypes in specimens from women with previous abnormal Pap smear results

The development of cervical cancer is strongly associated with the presence of persistent high-risk (HR) human papillomavirus (HPV) infection. Recently, the commercially manufactured PCR-based Roche AMPLICOR (AMP) and LINEAR ARRAY (LA) HPV tests have become available for HPV detection. However, knowledge of their clinical performance compared to the U.S. Food and Drug Administration-approved Hybrid Capture 2 (HC2) assay is limited. This study evaluated the concordance between the HC2, AMP, and LA tests in detecting HR-HPV among a cohort of 1,679 women with previous abnormal Pap smear results. Overall, 1,393 specimens (81.3%) generated concordant results for HR-HPV presence or absence by the three assays. The concordance levels were substantial between the HC2 and AMP tests (84.4%, kappa = 0.6419) and between the HC2 and LA tests (84.0%, kappa = 0.6341) and nearly perfect between the AMP and LA tests (97.8%, kappa = 0.9441). HR-HPV prevalence, as detected by the AMP or LA tests, was significantly higher among women with cytological or histological high-grade disease (CIN2 or greater) than that detected by HC2 (P < 0.0001). The AMP and LA tests exhibited greater sensitivity, but lower specificity, than HC2 for detecting HR-HPV among this cohort of women with underlying cervical abnormalities, particularly among subjects with histologically proven high-grade disease. Both PCR-based HPV tests may be valuable in the management of care for women with underlying cervical abnormalities, in predicting treatment success, and in studying the clearance or acquisition of new infections.     

Prospective evaluation of the Hybrid Capture 2 and AMPLICOR human papillomavirus (HPV) tests for detection of 13 high-risk HPV genotypes in atypical squamous cells of uncertain significance

The use of high-risk human papillomavirus (hrHPV) testing as an adjunct to cervical cytology in population-based screening programs is currently based on DNA hybridization and PCR assays. The aim of this study was to prospectively assess the diagnostic performance of the Hybrid Capture 2 test (HC2; Digene Corporation) in comparison with that of the recently developed PCR-based AMPLICOR HPV test (Roche Molecular Systems) for the detection of 13 hrHPV types. A reverse line blot hybridization assay (Innogenetics) was used as an internal reference standard in discordant cases. Two hundred seventy-one patients with atypical squamous cells of uncertain significance (ASCUS) in cervical samples underwent hrHPV testing. The chi-square test was performed to compare respective proportions. Totals of 160/271 (59%) and 156/271 (58%) were found to be positive for hrHPV with HC2 and AMPLICOR, respectively. Concordant results were obtained for 235 (86.7%) of the 271 samples (kappa statistic, 0.73 +/- 0.04). Considering types 26, 53, and 66 as oncogenic types, negative predictive values (NPVs) of HC2 and AMPLICOR were 92.8% and 87.8%, respectively (difference was not significant), and their respective accuracies were 94.8% and 91.9% (difference was not significant). Considering types 26, 53, and 66 as not oncogenic, the respective HC2 and AMPLICOR NPVs were 92.8% and 97.4% (difference was not significant), and accuracy was significantly higher for the AMPLICOR assay (95.9% versus 90.8% for HC2) (P<0.05). For ASCUS samples, the NPV was 92.8% for HC2 testing and might be compromised if the copy number of HPV DNA was low. The NPV was 97.4% for the AMPLICOR assay and might be compromised if HPV types 26, 53, and 66 were considered oncogenic. The accuracy of these two assays is good and is compatible with routine clinical use in the triage of ASCUS cases.     

Evaluation of the MagNA pure LC instrument for extraction of hepatitis C virus RNA for the COBAS AMPLICOR Hepatitis C Virus Test,version 2.0

The COBAS AMPLICOR system has played a major role in the transition of molecular diagnostics from research to routine clinical laboratory use by automating the nucleic acid amplification and detection processes. However, sample preparation remains a labor-intensive portion of the procedure. In this study, we evaluated the performance of the COBAS AMPLICOR Hepatitis C Virus Test, version 2.0 (Roche Molecular Systems, Branchburg, N.J.) following manual hepatitis C virus (HCV) RNA extraction versus automated extraction with the MagNA Pure LC instrument (Roche Applied Science, Indianapolis, Ind.). Parallel replicate testing was performed with standard dilutions of 100, 75, 60, and 0 HCV IU/ml and 153 clinical specimens. An analytical sensitivity of 75 IU/ml was achieved with either the manual or the standard-volume (200 microl) automated extraction methodologies (25 of 26 [96.2%]; 95% confidence interval [95% CI], 80.4 to 99.9), whereas the clinical sensitivity and specificity were both 100% with either extraction method. A large-volume (1 ml) automated extraction method was also evaluated with standard dilutions of 40, 25, 10, and 0 IU/ml and the same 153 clinical specimens. The analytical sensitivity of the COBAS AMPLICOR assay with the large-volume extraction method was 25 HCV IU/ml (26 of 26 [100%]; 95% CI, 86.8 to 100), whereas the clinical sensitivity and specificity were both 100%. The MagNA Pure LC instrument is a versatile, labor-saving platform capable of integration with minimal modification of the existing assay procedure. The increased sensitivity of the COBAS AMPLICOR Hepatitis C Virus Test, version 2.0 performed in conjunction with large-volume HCV RNA extraction may be important in HCV diagnostic testing as new therapeutic strategies evolve.     

Enhanced detection and typing of human papillomavirus (HPV) DNA in anogenital samples with PGMY primers and the Linear array HPV genotyping test

The Roche PGMY primer-based research prototype line blot assay (PGMY-LB) is a convenient tool in epidemiological studies for the detection and typing of human papillomavirus (HPV) DNA. This assay has been optimized and is being commercialized as the Linear Array HPV genotyping test (LA-HPV). We assessed the agreement between LA-HPV and PGMY-LB for detection and typing of 37 HPV genotypes in 528 anogenital samples (236 anal, 146 physician-collected cervical, and 146 self-collected cervicovaginal swabs) obtained from human immunodeficiency virus-seropositive individuals (236 men and 146 women). HPV DNA was detected in 433 (82.0%) and 458 (86.7%) samples with PGMY-LB and LA-HPV (P = 0.047), respectively, for an excellent agreement of 93.8% (kappa = 0.76). Of the 17,094 HPV typing results, 16,562 (1,743 positive and 14,819 negative results) were concordant between tests (agreement = 96.9%; kappa = 0.76). The mean agreement between tests for each type was 96.4% +/- 2.4% (95% confidence interval [CI], 95.6% to 97.2%; range, 86% to 100%), for an excellent mean kappa value of 0.85 +/- 0.10 (95% CI, 0.82 to 0.87). However, detection rates for most HPV types were greater with LA-HPV. The mean number of types per sample detected by LA-HPV (4.2 +/- 3.4; 95% CI, 3.9 to 4.5; median, 3.0) was greater than that for PGMY-LB (3.4 +/- 3.0; 95% CI, 3.1 to 3.6; median, 2.0) (P < 0.001). The number of types detected in excess by LA-HPV in anal samples correlated with the number of types per sample (r = 0.49 +/- 0.06; P = 0.001) but not with patient age (r = 0.03 +/- 0.06; P = 0.57), CD4 cell counts (r = 0.06 +/- 0.06; P = 0.13), or the grade of anal disease (r = -0.11 +/- 0.06; P = 0.07). LA-HPV compared favorably with PGMY-LB but yielded higher detection rates for newer and well-known HPV types.     

comparison of two commercial assays for detection of human papillomavirus (HPV) in cervical scrape specimens: validation of the Roche AMPLICOR HPV test as a means to screen for HPV genotypes associated with a higher risk of cervical disorders

Certain high-risk (HR) human papillomavirus (HPV) types are a necessary cause for the development of cervical disorders. Women with persistent HR HPV infections have an increased risk of developing high-grade cervical lesions, compared with those who have no or low-risk HPV infections. Therefore, implementation of HPV detection into cervical screening programs might identify women at risk of cervical cancer. Several HPV detection methods with different sensitivities and specificities are available. Recently, a new PCR-based technique, the Roche AMPLICOR HPV Test, was developed. This test recognizes a group of 13 HR HPV types simultaneously. This study was undertaken to validate and compare HPV detection in 573 cervical scrape specimens by the AMPLICOR HPV Test and the INNO-LiPA HPV detection/genotyping assay (SPF10-LiPA system version 1). Human beta-globin was not detected in nine specimens, which were therefore excluded from the comparison. Eleven scrape specimens containing HPV type 53 or 66 were also excluded from the comparison because these (probably) HR HPV types cannot be detected by the AMPLICOR HPV Test. The results of HPV detection by the Roche AMPLICOR HPV Test were confirmed by INNO-LiPA HPV detection/genotyping assay in 539/553 cases, showing an absolute agreement of 97.5% with a Cohen's kappa of 0.9327, indicating almost complete similarity of the two tests. Like the INNO-LiPA HPV detection/genotyping assay, the AMPLICOR HPV Test was sensitive, specific, feasible, and easy to handle. The value of the Roche AMPLICOR HPV Test with a broad-spectrum HR HPV detection has to be determined in prospective clinical studies.     

Performance of the MagNA pure LC robot for extraction of Chlamydia trachomatis and Neisseria gonorrhoeae DNA from urine and swab specimens

DNA from uncentrifuged urines (n = 195 and n = 202) and cervical swabs (n = 221 and n = 601) was extracted by the MagNA Pure LC robot and the Amplicor method to validate the robot's extraction for Chlamydia trachomatis and Neisseria gonorrhoeae testing by Roche PCR. The robot provided a highly sensitive and specific method of DNA extraction.     

Comparison of real-time multiplex human papillomavirus (HPV) PCR assays with the linear array HPV genotyping PCR assay and influence of DNA extraction method on HPV detection

Real-time human papillomavirus (HPV) type-specific multiplex PCR assays were developed to detect HPV DNA in specimens collected for the efficacy determination of the quadrivalent HPV (type 6, 11, 16, and 18) L1 virus-like particle (VLP) vaccine (Gardasil). We evaluated the concordance between type-specific multiplex HPV PCR and the widely used, commercially available Roche Linear Array genotyping PCR assay. Female genital swab specimens were tested for the presence of L1, E6, and E7 sequences of HPV type 6 (HPV6), HPV11, HPV16, HPV18, HPV31, HPV45, HPV52, and HPV58 and E6 and E7 sequences of HPV33, HPV35, HPV39, HPV51, HPV56, and HPV59 in type- and gene-specific real-time multiplex PCR assays. Specimens were also tested for the presence of L1 sequences using two versions of the Roche Linear Array genotyping assay. Measures of concordance of a modified version of the Linear Array and the standard Linear Array PCR assay were evaluated. With specimen DNA extraction using the Qiagen Spin blood kit held as the constant, multiplex PCR assays detect more HPV-positive specimens for the 14 HPV types common to both than either version of the Linear Array HPV genotyping assay. Type-specific agreements between the assays were good, at least 0.838, but were often driven by negative agreement in HPV types with low prevalence, as evidenced by reduced proportions of positive agreement. Overall HPV status agreements ranged from 0.615 for multiplex PCR and standard Linear Array to 0.881 for multiplex PCR and modified Linear Array. An alternate DNA extraction technique, that used by the Qiagen MinElute kit, impacted subsequent HPV detection in both the multiplex PCR and Linear Array assays.     

An improved in situ DNA hybridization protocol for detection of human papillomavirus (HPV) DNA sequences in paraffin-embedded biopsies

In situ DNA hybridization is becoming rapidly an important technique for detection and typing of human papillomaviruses (HPV) in epithelial lesions, some of which (those due to HPV 16, 18 and 31) seem to possess an increased risk for progression into an invasive squamous cell carcinoma. An improved in situ DNA hybridization technique (Technique II) was described, and the results obtained in a series of cervical and penile HPV lesions were compared with those given by the in situ hybridization technique (Technique I) previously used in our laboratory. Special emphasis was made to increase the sensitivity with three basic alterations of the hybridization protocol; omission of the 0.2 N HCl wash, use of increased proteinase K concentration (from 50 micrograms/ml to 1 mg/ml), and elevated denaturation temperature (obtained by a heating block instead of an incubator). Poly-D-lysine as a slide-coating medium was replaced by Kodak Photo-Flo 200 to improve the attachment of the tissue sections on the slides. Identical HPV DNA types were discovered by the two hybridization techniques. The attachment of the tissue sections was equal on the slides coated with either poly-D-lysine or Kodak Photo-Flo 200, and the latter did not interfere with the sensitivity of in situ hybridization. The hybridization signals for HPV DNA were weak or moderate in 15/16 lesions with Technique I, but intense in 10/16 lesions with Technique II (P less than 0.001). Furthermore, the resolution of Technique II seemed to be superior to that of Technique I, while being capable of disclosing HPV DNA in the intermediate cell layers (P less than 0.001) and in basal/parabasal cell layers (P less than 0.025) of both the cervical and penile lesions. The discovery of HPV DNA in the parabasal cells provides important clues to the understanding of the biology of HPV infection in the squamous epithelium, and makes this improved in situ DNA hybridization technique invaluable in assessing the lesions, where low copy numbers of HPV are to be expected.     

Development of an automated extraction procedure for detection of human papillomavirus DNA in liquid based cytology samples

Liquid based cytology samples are being used increasingly to improve cervical screening and have the advantage that residual cell suspension is available for other tests such as human papillomavirus (HPV) detection. However, as the transport medium is optimised for downstream cytology, problems can be experienced during extraction of nucleic acid. This study aimed to develop a robust protocol for automated extraction of HPV DNA from cervical, liquid based cytology samples using a high throughput robotic system. Considerable modification of existing clinical extraction protocols for swab specimens, together with optimisation of required sample input volume was required to reduce sample blockage during the extraction to acceptable levels. The blockage rate and optimal processing volume was assessed by extracting a fixed volume (1/4) of re-suspended material from the centrifuged pellets of 10, 5 and 1 ml aliquots of 200 specimens. Analysis revealed 17.5% blockage with specimens originating from 10 ml aliquots; 3% with 5 ml and no blockage with 1 ml aliquots of the same samples. A 3% blockage level is acceptable for an automatic well clearance procedure to be followed. HPV testing of the extracts by real-time PCR showed a 1.5% loss of sensitivity in extracts originating from 1 ml aliquots as compared with 5 ml aliquots with a consequent loss of detectable HPV genotypes after reverse hybridisation. In short, 5 ml of liquid based cytology specimen is recommended for nucleic acid extraction, to allow optimal detection of HPV types in clinical samples while retaining maximum efficiency of the robotic extraction procedure.     

Automated extraction of genomic DNA from medically important yeast species and filamentous fungi by using the MagNA Pure LC system

A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (10(5) to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sensitivity when DNA was extracted manually; in 9 of 28 runs, we could achieve a higher sensitivity of 1 CFU/ml blood, which was found to be significant (p 相似文献   

Entirely automated quantification of human immunodeficiency virus type 1 (HIV-1) RNA in plasma by using the ultrasensitive COBAS AMPLICOR HIV-1 monitor test and RNA purification on the MagNA pure LC instrument

The ultrasensitive COBAS AMPLICOR HIV-1 Monitor test was complemented with automated RNA purification on the MagNA Pure LC instrument. This enabled entirely automated ultrasensitive assessment of viral loads in human immunodeficiency virus type 1 (HIV-1)-infected individuals. The detection limit of the fully automated assay and the viral load measurements in 80 clinical samples were found to be in good agreement with those of the conventional ultrasensitive COBAS AMPLICOR HIV-1 Monitor test. The fully automated assay showed markedly reduced hands-on time and was found to be suitable for the routine assessment of HIV-1 viral loads in a clinical diagnostic laboratory.     

Comparison of the Third Wave Invader human papillomavirus (HPV) assay and the digene HPV hybrid capture 2 assay for detection of high-risk HPV DNA

This study compared the clinical performance of the Digene Hybrid Capture 2 (HC2) assay to that of a prototype Third Wave Invader human papillomavirus (HPV) (IHPV) analyte-specific reagent-based assay for the detection of oncogenic or "high-risk" (HR) HPV DNA using liquid-based cytology specimens. In total, 821 ThinPrep vials were tested using both assays. In accordance with the type-specific probes contained within each test, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the IHPV assay were 95.9%, 97.6%, 97.5%, and 96.1%, respectively, and those for the HC2 assay were 98.1%, 86.2%, 87.1%, and 97.9%. Overall, the sensitivity and NPV were comparable between the assays, but the IHPV assay demonstrated a better specificity and PPV, since the IHPV assay had fewer false-positive HR HPV results. The incorporation of an internal control to evaluate the cellularity of the test material is an important feature of the IHPV assay and should reduce the risk of false-negative results due to insufficient sample collection rather than the lack of HR HPV DNA. An additional benefit of the IHPV assay was the smaller sample volume required (1 ml versus 4 ml for the HC2 assay).     

Comparison of the hybrid capture 2 and cobas 4800 tests for detection of high-risk human papillomavirus in specimens collected in PreservCyt medium

Clinical cervical cytology specimens (n = 466) collected in PreservCyt (Hologic Inc.) were used to evaluate the agreement between Hybrid Capture 2 (hc2; Qiagen) and cobas 4800 (c4800; Roche Molecular Diagnostics) for the detection of high-risk human papillomavirus (HR HPV) genotype infections. The agreement between the two assays was 93.8% (kappa = 0.87; 95% confidence interval, 0.828 to 0.918), with 186 and 251 concordant positive and negative results, respectively. All 186 concordant positives were confirmed using the Linear Array (LA; Roche Molecular Diagnostics) genotyping test. Of the 29 samples with discordant results (6.2%), 18 were hc2 positive and LA verified 17 as positive for HR HPV. Eleven discordant specimens were c4800 positive, and LA confirmed 5 as positive for HR HPV. As of October 2009, practice guidelines in Alberta, Canada, recommend reflex HPV testing for women over 30 years old with atypical squamous cells of undetermined significance (ASCUS) and for women over 50 years old with low-grade squamous intraepithelial lesions (LSIL) to help prioritize those who should undergo further evaluation. In this study, agreement between hc2 and c4800 results for samples from women over 30 years old with ASCUS cytology was 92.3% (n = 13), while no samples from women over 50 years old with LSIL cytology were identified for analysis.     

Detection of HIV-1 proviral DNA with the AMPLICOR HIV-1 DNA Test, version 1.5, following sample processing by the MagNA Pure LC instrument.

BACKGROUND: The AMPLICOR HIV-1 DNA Test, version 1.5 (AMP HIV-1 DNA 1.5), is a new commercially available PCR assay for the detection of human immunodeficiency virus type 1 (HIV-1) proviral DNA in human whole blood. OBJECTIVE: This study evaluates the performance characteristics of the assay following automated sample processing by the MagNA Pure LC instrument (MP). STUDY DESIGN: Analytical sensitivity and reproducibility were assessed by testing replicate HIV-1 DNA dilution panels over 5 days. Clinical sensitivity and specificity were studied among 28 HIV-1 DNA-positive clinical specimens, 60 specimens from healthy blood donors, and 63 specimens from HIV-1-seropositive patients with HIV-1 RNA plasma levels ranging from <50 to >100,000 copies/mL. RESULTS: Following MP sample processing, the assay yielded an analytical sensitivity (95% detection rate) of 66.3 copies/mL (95% CI, 50.7-106.8), with clinical sensitivity and specificity of 100%. CONCLUSIONS: MP is a reliable, labor-saving platform capable of processing specimens for AMP HIV-1 DNA 1.5. When combined with MP sample processing, AMP HIV-1 DNA 1.5 is a sensitive and reproducible assay for the detection of HIV-1 DNA in clinical whole blood specimens. However, the current AMP HIV-1 DNA 1.5 kit configuration may result in inefficient utilization of reagents.     

Quantification of hepatitis B virus (HBV) DNA with a TaqMan HBV analyte-specific reagent following sample processing with the MagNA pure LC instrument

TaqMan hepatitis B virus (HBV) analyte-specific reagent (ASR; Roche Molecular Systems, Inc., Branchburg, NJ) is designed for the quantification of HBV DNA in serum or plasma. The performance characteristics of TaqMan HBV ASR following automated sample processing with the MagNA Pure LC instrument (MP; Roche Applied Science, Indianapolis, IN) were evaluated in this study. Analytical sensitivity and precision were assessed with commercially available HBV standards, while clinical serum specimens from HBsAg-seropositive patients and healthy blood donors were used to determine clinical sensitivity, specificity, and correlation with other commercially available assays. Analytical studies yielded a limit of detection of 2.4 IU/ml, with good linearity and correlation (R(2) = 0.9958) with expected HBV DNA titers over a wide range (6.0 x 10(0) to 2.1 x 10(8) IU/ml). Clinical sensitivity and specificity of the assay combined with automated sample processing were both 100%. Comparison of TaqMan HBV ASR and VERSANT HBV DNA 3.0 assay (bDNA; Bayer HealthCare LLC, Tarrytown, NY) results among clinical specimens yielded good correlation (R(2) = 0.9237), with a mean difference in titer of -0.213 log(10) IU/ml (95% confidence interval, -0.678 to 1.10 log(10) IU/ml). The overall test failure rate was 2.0% among 204 clinical serum specimens tested. Total time required for MP sample processing and automated postelution handling of 24 samples was 224 min, with 57 min of actual hands-on time. MP is a reliable, labor-saving platform suitable for use with TaqMan HBV ASR, providing sensitive and accurate quantification of HBV DNA levels over a range of 8 log(10) IU/ml.     

Modulation of apoptosis by human papillomavirus (HPV) oncoproteins

Summary. The regulation of host-mediated apoptosis by the E6 and E7 oncoproteins has garnered attention because it is believed to be an important strategy employed by high-risk (HR)-human papillomaviruses (HPVs) to evade immune surveillance. Additionally, the revelation that E5 can protect cells from tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis suggests that it may also play a role in undermining host defense mechanisms. Cellular transformation is an unintended consequence of persistent infection by HR-HPVs, and it is therefore likely that the primary function of E5, E6 and E7 is to regulate cell survival throughout the normal viral life cycle in order to ensure viral replication and promote the spread of progeny. The purpose of this article is to review the literature on the regulation of host-mediated apoptosis by E5, E6 and E7 that describes the mechanisms employed by HR-HPVs to persist in the host and create the conditions necessary for cellular transformation.