Comparison of five different polymerase chain reaction methods for detection of human papillomavirus in cervical cell specimens

The polymerase chain reaction (PCR) methods enable the detection of large number of human papillomavirus (HPV) genotypes that infect the anogenital tract. In this study, two groups of cervical scrapes with abnormal cytomorphology were analysed. The first group was tested with three sets of consensus primers located within the L1 region of HPV genome, MY09/MY11 (i.e. MY), L1C1/L1C2-1/L1C2-2 (i.e. LC) and pI-1/pI-2 (i.e. pI) primer sets, while the second group of samples, which were all negative with the MY primers, was tested further with the LC primers, as well as with the GP5/GP6 (i.e. GP) primers. The GP primers were used in the nested PCR following amplification with the MY primers (i.e. MY/GP nested PCR). Samples from both groups were also tested with type-specific primers for HPV types 6/11, 16, 18, 31 and 33. In the first study group (N=164) there were 76.2% positive results obtained with at least one set of consensus primers. There were 62.2, 39, 62.2 and 59.1% positive results obtained with the MY, the pI, the LC and the HPV type-specific primer sets, respectively. The best results were obtained when both the MY and the LC primer sets were used, because in combination they detected 75% positive samples compared to 62.2% when used alone. There were 2. 4% samples negative with all consensus primers, but positive with one of the HPV type-specific primers, which increased the overall positivity rate to 78.6%. In the second study group (N=250) there were 8.4, 38.8 and 4% samples positive with the LC primers, the nested MY/GP and the HPV type-specific primer sets, respectively. Thus, the use of the MY/GP nested PCR increased significantly the positivity rate of HPV DNA detection and should be used for samples with a low copy number of HPV DNA. In conclusion, the following diagnostic protocol would be appropriate for detection of cancer-related HPVs: preselection of samples with the MY and the LC primers, additional amplification of the MY- and the LC-negative samples with the MY/GP nested PCR and HPV typing of consensus PCR-positive samples with the HPV type-specific primers.     

A novel and rapid PCR-based method for genotyping human papillomaviruses in clinical samples

Many human papillomavirus (HPV) genotypes are associated with cervical carcinoma. We demonstrate the utility of an innovative technique for genotyping of HPV in cervical tissue samples. This method provides an accurate means of identification of the specific HPV genotypes present in clinical specimens. By using the MY09-MY11 and the GP5(+)-GP6(+) consensus primer pairs, HPV sequences were amplified by nested PCR from DNA isolated from cervical smear samples. This led to the production of an approximately 140-bp PCR product from the L1 (major capsid) gene of any of the HPVs present in the sample. PCR was performed with a deoxynucleoside triphosphate mixture which resulted in the incorporation of deoxyuridine into the amplified DNA product at positions where deoxythymidine would normally be incorporated at a frequency of about once or twice per strand. Following the PCR, the product was treated with an enzyme mix that contains uracil N-glycosylase (UNG) and endonuclease IV. UNG removes the uracil base from the nucleotide, and endonuclease IV cleaves the phosphodiester bond at this newly formed abasic site, producing fragments of various sizes. By having end labeled one of the amplification primers, a DNA ladder which is analogous to a "T-sequencing ladder" was produced upon electrophoresis of the products. By comparing this T-sequencing ladder to the known sequences of HPVs, the genotypes of unknown HPV isolates in samples were assigned. Data showing the utility of this technique for the rapid analysis of clinical samples are presented.     

Development and clinical evaluation of a highly sensitive PCR-reverse hybridization line probe assay for detection and identification of anogenital human papillomavirus.

Human papillomavirus (HPV) can be detected by amplification of viral DNA. A novel PCR primer set generating a short PCR fragment (SPF PCR) was used for amplification of a fragment of only 65 bp from the L1 region and permitted ultrasensitive detection of a broad spectrum of HPV genotypes. The intra- and intertypic sequence variations of the 22-bp interprimer region of this amplimer were studied. Among 238 HPV sequences from GenBank and clinical specimens, HPV genotypes were correctly identified based on the 22-bp sequence in 232 cases (97.2%). Genotype-specific probes for HPV genotypes 6, 11, 16, 18, 31, 33 to 35, 39, 40, 42 to 45, 51 to 54, 56, 58, 59, 66, 68, 70, and 74 were selected, and a reverse hybridization line probe assay (LiPA) (the INNO-LiPA HPV prototype research assay) was developed. This LiPA permits the use of amplimers generated by the SPF as well as the MY 09/11 primers. The assay was evaluated with a total of 1, 354 clinical specimens, comprising cervical scrapes (classifications ranging from normal cytology to severe dyskaryosis) and formalin-fixed, paraffin-embedded cervical carcinoma samples. LiPA results were highly concordant with sequence analysis of the SPF amplimer, genotype-specific PCR, and sequence analysis of amplimers generated by MY 09/11 primers. The sensitivity of the SPF primers was higher than that of the GP5(+)/6(+) primers over a broad range of HPV types, especially when multiple HPV genotypes were present. In conclusion, the SPF LiPA method allows extremely sensitive detection of HPV DNA as well as reliable identification of HPV genotypes in both cervical smears and paraffin-embedded materials.     

Improved amplification of genital human papillomaviruses

Genital human papillomaviruses (HPVs) are commonly detected from clinical samples by consensus PCR methods. Two commonly used primer systems, the MY09-MY11 (MY09/11) primers and the GP5+-GP6+ (GP5+/6+) primers, amplify a broad spectrum of HPV genotypes, but with various levels of sensitivity among the HPV types. Analysis of the primer-target sequence homology for the MY09/11 primers showed an association between inefficient amplification of HPV types and the number and position of mismatches, despite accommodation of sequence variation by inclusion of degenerate base sites. The MY09/11 primers were redesigned to increase the sensitivity of amplification across the type spectrum by using the same primer binding regions in the L1 open reading frame. Sequence heterogeneity was accommodated by designing multiple primer sequences that were combined into an upstream pool of 5 oligonucleotides (PGMY11) and a downstream pool of 13 oligonucleotides (PGMY09), thereby avoiding use of degenerate bases that yield irreproducible primer syntheses. The performance of the PGMY09-PGMY11 (PGMY09/11) primer system relative to that of the standard MY09/11 system was evaluated with a set of 262 cervicovaginal lavage specimens. There was a 91.5% overall agreement between the two systems (kappa = 0.83; P < 0.001). The PGMY09/11 system appeared to be significantly more sensitive than the MY09/11 system, detecting an additional 20 HPV-positive specimens, for a prevalence of 62.8% versus a prevalence of 55.1% with the MY09/11 system (McNemar's chi(2) = 17.2; P < 0.001). The proportion of multiple infections detected increased with the PGMY09/11 system (40. 0 versus 33.8% of positive infections). HPV types 26, 35, 42, 45, 52, 54, 55, 59, 66, 73, and MM7 were detected at least 25% more often with the PGMY09/11 system. The PGMY09/11 primer system affords an increase in type-specific amplification sensitivity over that of the standard MY09/11 primer system. This new primer system will be useful in assessing the natural history of HPV infections, particularly when the analysis requires HPV typing.     

Nested PCR with the PGMY09/11 and GP5(+)/6(+) primer sets improves detection of HPV DNA in cervical samples

Based on epidemiological and research evidence, HPV has a causal role in cervical carcinogenesis. Several HPV detection methods exist to date; the most commonly used method for detection of genital HPVs consists of nested PCR using the MY09/11 and GP5(+)/6(+) primer sets (MY/GP(+)). Recently, the PGMY09/11 primer set, a modified version of the MY09/11 primer set, was introduced for single PCR and was found to detect a wider range of HPV types. The next logical step was taken and the efficacy of nested PCR using the PGMY09/11 and GP5(+)/6(+) primer sets (PGMY/GP(+)) to detect HPV in cervical samples was evaluated. In this comparative study, nested PCR using the novel PGMY/GP(+) primer set combination was found to be more type sensitive than the nested PCR with the MY/GP(+) primer sets, detecting a wider range of HPV types, low copy HPVs, and better characterizing samples infected with multiple strains of HPV. Standardization and use of the PGMY/GP(+) PCR system could aid physicians in providing more efficient HPV screening and better treatment for patients.     

A two-tier polymerase chain reaction direct sequencing method for detecting and typing human papillomaviruses in pathological specimens.

An in-house polymerase chain reaction direct sequencing (PCR-DS) approach for HPV detection and typing was developed, taking advantage of two widely used pairs of human papillomavirus (HPV)-specific PCR primers, MY09/MY11 and GP5/GP6, and 33P-labeled dideoxynucleotides. In this study, 105 pathological specimens were examined: 89% were diagnosed as cervical intraepithelial neoplasia (CIN) grade I-III, 76.2% were HPV-positive by PCR-DS. The PCR using GP5/GP6 (first tier) and MY09/MY11 primers (second tier for the GP5/GP6-negative samples) detected additional 15%-25% HPV-positive samples compared with each pair used separately. Direct sequencing was then used to type the HPV. A readout of a sequence as short as 34 nucleotides within a specific region in the L1 gene is sufficient to type known or novel sequences. Because of its high sensitivity and cost-effectiveness, the two-tier PCR-DS was adopted by the authors as the current method of choice for HPV diagnosis with ultimate sequence precision.     

Validity of vaginal testing in detecting human papillomavirus (HPV) genotypes.

The aim of this study was to assess the validity and usefulness of vaginal scrapes in detecting cervical human papillomavirus (HPV) DNA by the polymerase chain reaction (PCR). The study group comprised 23 women tested positive and 28 women tested negative for cervical HPV DNA by PCR, and confirmed by histopathology. At the time of specimen collection, both vaginal and endocervical scrapes were taken from these women, and tested for HPV DNA by PCR, using MY09/MY11 primer system. HPV genotypes were analyzed by hybridizing PCR products with HPV type-specific biotinylated probes. HPV DNA was detected in both vaginal and cervical scrapes from the HPV-positive, but not from HPV-negative group. In the HPV-positive group, the same HPV type was found in vaginal and endocervical scrapes, giving a positive predictive value of 1.0. The results indicate that HPV types can be detected in vaginal scrapes, and recommend utilization of the less invasive vaginal testing for the routine detection of HPV DNA.     

Detection of high-risk subtypes of human papillomavirus in cervical swabs: routine use of the Digene Hybrid Capture assay and polymerase chain reaction analysis

Human papillomaviruses (HPVs) are major causative agents in the pathogenesis of cervical cancer, and more than twenty types are associated with its development. With the introduction of liquid-based preparation systems, it is envisaged that large-scale HPV testing will be established in the near future. Preliminary studies demonstrate the accessibility of these samples for DNA testing using both the Digene Hybrid Capture assay (DHCA) and polymerase chain reaction (PCR) techniques. This study aims to assess the validity and sensitivity of the DHCA system to detect high-risk HPV DNA, using two sets of HPV consensus primers (Gp5+/Gp6+ and MY09/MY11) in tandem with routine assessment of cervical smear and biopsy samples. Results indicate that the combination of DHCA and PCR detects more high-grade lesions than does the DHCA alone. DHCA-negative cases were categorised by subsequent PCR amplification into low-grade HPV-negative (12/16) cervical lesions and high-grade HPV-positive (7/9) cervical lesions. Gp5+/Gp6+ primers were less sensitive in detecting HPV-positive samples than was the MY09/MY11 primer set. These results support the use of high-risk HPV testing by DHCA, with subsequent analysis of DHCA-negative samples by PCR using the MY09/MY11 primers.     

Routine genotyping of human papillomavirus samples in Denmark

In order to examine a sensitive unbiased consensus PCR with routine sequencing for HPV typing, we analysed Danish male and female patients suspected of having an HPV infection. We used the well-characterised nested PCR setting with MY09/MY11 and GP5+/GP6+ primers, followed by routine cycle sequencing. Of 1283 clinical samples from female patients based on suspected HPV infection, we found 379 (29%) negatives and 894 (70%) positives. Samples containing >5000 HPV copies/ml were genotyped by sequencing. Of the 552 HPV genotyped samples from women >15 years of age, 398 were characterised as high-risk types and the remaining 154 as low-risk types. The most commonly found high-risk types were HPV-16, HPV-31, HPV-33, HPV-18, HPV-58, and HPV-52, and the most commonly found low-risk types were HPV-6, HPV-53 and HPV-11. In addition, we observed that other typing assays could not perform as sensitively or accurately as the nested PCR/cycle sequencing method used in this study. For instance, 87 out of 552 genotyped samples could not have been typed correctly in the Hybrid Capture II assay. Of these 87 samples, 46 (53%) were considered as high-risk types.     

PCR detection of human papillomavirus: comparison between MY09/MY11 and GP5+/GP6+ primer systems.

Human papillomavirus (HPV) is an etiologic agent of cervical cancer and is the most common sexually transmitted disease in women. PCR amplification of HPV genomes is the most sensitive method for the detection of cervicovaginal HPV. We have compared the two most commonly used PCR primer sets, MY09/MY11 (MY-PCR) and GP5+/GP6+ (GP+-PCR), for the detection of HPV DNA in cervicovaginal lavage samples from 208 women. Oligonucleotide probes for 39 different HPV types were used. Both primer sets amplified a wide spectrum of HPV genotypes and detected similar overall prevalences of 45% (94 of 208) and 43% (89 of 208), respectively. The MY-PCR system detected 27 of 30 (90%) samples with multiple HPV types, whereas the GP+-PCR system detected 14 of 30 (47%) samples with multiple HPV types. Differences in the detection of HPV types 35, 53, and 61 were noted between the two primer systems. Serial dilution of plasmid templates indicated a 3-log decrease in the amplification of HPV type 35 by MY-PCR and HPV types 53 and 61 by GP+-PCR. These results indicate that although the MY-PCR and GP+-PCR identified nearly equivalent prevalences of HPV in a set of clinical samples, differences in the detection of specific types and infections with multiple types were found. Differences in the sensitivities and characteristics of the PCR systems for the detection of HPV within clinical samples should be considered when comparing data between studies and/or in designing new studies or clinical trials.     

Detection of human papillomavirus from archival tissues in cervical cancer patients in Mauritius.

BACKGROUND: Around half a million new cases of cervical cancer are diagnosed worldwide each year, accounting for almost 300,000 deaths. Development of cervical cancer can be multi-factorial, but high-risk human papillomaviruses (HPV) have been associated with the aetiology of cervical cancer. It is believed that HPV DNA integrates into the host DNA causing abnormal cell growth with cells becoming carcinogenic and spreading metastatically. In Mauritius, cervical cancer account for 65% of gynaecological cancers and 3.4% of the cervical cancers are diagnosed at the stage of carcinoma in situ. OBJECTIVES: To determine the prevalence of HPV in histological samples from patients with cervical cancer in Mauritius. STUDY DESIGN: DNA from archival cervical samples from a cohort of 65 patients suffering from cervical cancer and controls from Mauritius were tested for the presence of HPV using MY09/11 and GP5+/6+ primer sets. RESULTS: In a cohort of 65 patients from Mauritius, diagnosed with cervical cancer in the year 2000, 19% of cervical histology sections were found to be positive for the presence of high-grade HPV, exclusively HPV18 using MY09 and MY11 primers. Only 15% of the Mauritian population is over 50 years of age, whereas 66% (35) of the diagnosed cases of cervical cancer were seen in patients above 50 years with 50% (5) affected with HPV. These findings suggest that for an infection with HPV to develop into cancer may take years if not decades. Differences were noted using two different primer sets, MY09/11 and GP5+/6+. The latter produce a much smaller amplicon (150bp) compared to the former ( approximately 450bp). Seven additional positive cases were detected with the GP5+/6+ primer set, resulting in an apparent prevalence of 32% as compared to the 19% seen with the MY09/11 primer set. This may indicate that some degradation of the target DNA has occurred during processing and storage of histological samples. CONCLUSION: Using primer sets MY09/11 and GP5+/6+, only HPV type 18 was found in the Mauritian cohort with a prevalence of 32%.     

Comparison between the Hybrid Capture II test and a PCR-based human papillomavirus detection method for diagnosis and posttreatment follow-up of cervical intraepithelial neoplasia

Human papillomavirus (HPV) infection is the major cause of cervical cancer and its precursor, cervical intraepithelial neoplasia (CIN), and HPV testing has therefore been proposed for improved triaging and follow-up of women treated for CIN. We compared two common HPV DNA detection tests (Hybrid Capture II [HCII] and PCR-enzyme immunosorbent assay (EIA) using the primers GP5+/GP6+ followed by HPV typing with reverse dot blot hybridization) for sensitivity and specificity for detection of CIN and of CIN recurrence after treatment. Two hundred and thirty-nine women referred to the Department of Obstetrics and Gynaecology in V?ster?s, Sweden, were enrolled because of atypical Pap smears; 177 of these were later treated for dysplasia by conization or loop diathermy. Samples for HPV DNA testing were taken before and 4 to 6 months after treatment. There was substantial agreement between the HCII and PCR-EIA (kappa, 0.70 before treatment and 0.72 after treatment). The sensitivity for histopathologically confirmed CIN III was 100.0% for PCR-EIA and 95.6% for HCII. For patients with CIN II or worse (CIN II+), the sensitivities were 92.9% (PCR-EIA) and 91.8% (HCII). The specificities for CIN II+ in the pretreatment setting were 30.4% for PCR-EIA and 24.1% for HCII. After treatment, the sensitivities for CIN III in cytology were 100.0% by both methods, and for CIN II+, sensitivities were 80.0% by both methods. The specificities for CIN II+ in the posttreatment setting were 83.5% for PCR and 85.4% for HCII. In conclusion, the sensitivities of both PCR-EIA and HCII are high and almost equal, suggesting that both methods are suitable as tools for detection and posttreatment follow-up of CIN II-III.     

Use of PGMY primers in L1 consensus PCR improves detection of human papillomavirus DNA in genital samples

The novel PGMY L1 consensus primer pair is more sensitive than the MY09 and MY11 primer mix for detection and typing with PCR of human papillomavirus (HPV) DNA in genital specimens. We assessed the diagnostic yield of PGMY primers for the detection and typing of HPV by comparing the results obtained with PGMY09/PGMY11 and MY09/MY11/HMB01 on 299 genital samples. Amplicons generated with PGMY primers were typed with the line blot assay (PGMY-line blot), while HPV amplicons obtained with the degenerate primer pool MY09/MY11/HMB01 were detected with type-specific radiolabeled probes in a dot blot assay (standard consensus PCR test). Cervicovaginal lavage samples (N = 272) and cervical scrape samples (N = 27) were tested in parallel with both PCR tests. The PGMY-line blot test detected the presence of HPV DNA more frequently than the standard consensus PCR assay. The concordance for HPV typing between the two assays was 84.3% (214 of 255 samples), for a good kappa value of 0.69. Of the 177 samples containing HPV DNA by at least one method, 40 samples contained at least one HPV type detected only with PGMY-line blot, whereas positivity exclusively with the standard consensus PCR test was found for only 7 samples (P < 0.001). HPV types 45 and 52 were especially more frequently detected with PGMY than MY primers. However, most HPV types were better amplified with PGMY primers, including HPV-16. Samples with discordant results between the two PCR assays more frequently contained multiple HPV types. Studies using PGMY instead of MY primers have the potential to report higher detection rates of HPV infection not only for newer HPV types but also for well-known genital types.     

A pilot study on the distribution of human papillomavirus genotypes and HPV-16 variants in cervical neoplastic lesions from Ecuadorian women

Human papillomaviruses (HPVs) are the cause of cervical intraepithelial neoplasia and invasive carcinomas of the uterine cervix. The distribution of specific HPV genotypes varies greatly across populations and HPV surveys have been performed in different geographical regions in order to apply appropriate vaccine strategies. The aim of this study was to determine the spectrum of HPV genotypes and HPV-16 variants among women with cervical lesions living in Ecuador. A total of 71 cases have been analyzed, including 32 chronic cervicitis, 29 cervical intraepithelial neoplasia grade 1, and 10 cervical intraepithelial neoplasia grade 2-3. HPV sequences were detected by broad spectrum consensus-primer-pairs MY09/MY11 and GP5+/GP6+-based polymerase chain reaction and characterized by nucleotide sequence analysis. Overall, 31 (43.7%) cases were HPV positive with prevalence rates of 37.5%, 44.8%, and 60% in patients with chronic cervicitis, cervical intraepithelial neoplasia grade 1 and cervical intraepithelial neoplasia grade 2-3, respectively. Among the positive cases, the most common genotypes were HPV 16 (64.5%) and HPV 81 (29%) followed by HPV 31, 53, 56, and 58, in descending order of prevalence. Seventeen (85%) HPV-16 isolates were classified as European and three (15%) as African-1 variant on the basis of nucleotide signature present within the MY09/MY11 L1 sequence. The results suggest that HPV 16 has a very high prevalence among women with cervical lesions in Ecuador; therefore, an effective HPV-16 based vaccine should prevent the development of cervical cancer in a large proportion of Ecuadorian women.     

Detection of human papillomavirus in cervical intra-epithelial neoplasia, using in situ hybridization and various polymerase chain reaction techniques

One hundred and forty-eight randomly chosen neutral-buffered formaldehyde-fixed cervical biopsies in which cervical intra-epithelial neoplasia (CIN) I–III had been diagnosed were tested for HPV (human papilloma virus) DNA by in situ hybridization (ISH) and polymerase chain reaction (PCR). For ISH, we utilized a biotinylated panprobe and type-specific, genomic probe sets. For PCR, we used the general primers GP5/GP6 and their recently described, elongated version GP5+/GP6+, and included the modification of hot-start PCR. Amplified DNA was detected by gel electrophoresis and slot blot hybridization. The positivity rate of ISH was 59% for all biopsies and 69%, 62% and 46% for CIN I, II and III, respectively. The sensitivity of GP5/GP6 was 74% with cold-start PCR and 78% with hot-start PCR. When GP5+/GP6+ was used, the sensitivity increased to 89% with cold-start PCR and to 95% with hot-start PCR. Based on the most sensitive PCR technique, HPV detection was 93%, 95% and 96% in CIN I, II and III, respectively. The number of HPV types decreased with the severity of the lesion, and HPV 16 was the predominant type. Multiple HPVs were rare and almost all HPV-positive cases could be typed. ISH and slot blot hybridization correlated well regarding HPV typing specificity. Our results confirm that distinct HPV types are present in a high proportion of cases of CIN. The sensitivity of ISH is lower than that of PCR. Furthermore, the modified general primers GP5+/GP6+ give a higher yield than GP5/GP6, while hot-start PCR increases sensitivity even further.     

Single-tube real-time nested polymerase chain reaction for detecting human papillomavirus DNA.

A single-tube real-time nested polymerase chain reaction (PCR) was developed to detect human Papillomavirus (HPV) DNA in a closed tube system. The oligonucleotide primers MY09/MY11 and GP5+/GP6+ were included in contiguous reactions, thus eliminating the need to transfer first round PCR product into a second tube. The sensitivity and specificity of the optimized single-tube nested PCR were comparable with that achieved by two separate reactions on a conventional thermal block system using serial dilutions derived from plasmids containing DNA of 20 HPV types. A minimum of 10 copies of HPV types 11 and 16 DNA could be detected by both systems. In clinical samples, HPV types 1A, 2, 3, 5, 6-8, 10, 11, 14, 16, 17, 18, 20, 31, 33, 35, 39, 45, 49, 50, 52-54, 57, 62, 66, 70, CP8304 and LVX82/MM7 could be detected by both PCR methods. A total of 145 samples collected from patients were tested for the presence of HPV DNA with the two PCR systems; 124 (86.1%) of 144 samples gave concordant results in both assays. The HPV DNA positive PCR amplicons were typed and concordant results were obtained in 47 of 67 positive samples tested in both amplicons. In samples containing multiple HPV types at least one type was common to both amplicons.     

A non-radioactive PCR enzyme-immunoassay enables a rapid identification of HPV 16 and 18 in cervical scrapes after GP5+/6+ PCR

In previous studies, general primer mediated PCR (GP5+/6+ PCR) was applied successfully to detect a broad spectrum of human papillomaviruses (HPV) in cervical scrapes. In order to facilitate PCR based HPV detection and typing, a colourimetric microtitre plate based hybridisation assay was developed. The method utilised one biotinylated primer (bio-GP6+) in the GP-PCR. Biotinylated PCR products were captured on streptavidin coated microtitre plates, denaturated and hybridised to digoxigenin (DIG) labelled HPV specific internal oligo probes. The DIG labelled hybrids were detected using an enzyme immunoassay (EIA). Since HPV 16 and 18 are the most common HPV types found in cervical carcinomas, this approach was initiated for these two types. Cross-hybridisation reactions were not detected when the specificity of this PCR-EIA for HPV 16 and 18 was tested on a panel of 20 different HPV genotypes. The sensitivity of the assay was found to be between 10 and 100 HPV 16 and 18 viral genomes in a background of 100 ng cellular DNA. This was similar to the detection limit of Southern blot analysis of PCR products with radioactively labelled oligonucleotides. A group of cytomorphologically normal (n = 89) and abnormal (n = 96) cervical scrapes were composed of HPV 16 and HPV 18 positive and HPV negative scrapes. All HPV 16 and 18 positive smears were detected by PCR-EIA. These results indicate that PCR-EIA has the potential for a rapid and sensitive HPV DNA test for day-to-day routine examination of cervical scrapes. © 1996 Wiley-Liss, Inc.     

Comparisons of HPV DNA detection by MY09/11 PCR methods

Two modifications to the original L1 consensus primer human papillomavirus (HPV) PCR method, MY09-MY011, using AmpliTaq DNA polymerase (MY-Taq), were evaluated for HPV DNA detection on clinical specimens from a cohort study of cervical cancer in Costa Rica. First, HPV DNA testing of 2978 clinical specimens by MY09-MY011 primer set, using AmpliTaq Gold DNA polymerase (MY-Gold) were compared with MY-Taq testing. There was 86.8% total agreement (kappa = 0.72, 95%CI = 0.70-75) and 69.6% agreement among positives between MY-Gold and MY-Taq. MY-Gold detected 38% more HPV infections (P < 0.0001) and 45% more cancer-associated (high-risk) HPV types (P < 0.0001) than MY-Taq, including 12 of the 13 high-risk HPV types. Analyses of discordant results using cytologic diagnoses and detection of HPV DNA by the Hybrid Capture 2 Test suggested that MY-Gold preferentially detected DNA positive specimens with lower HPV viral loads compared with MY-Taq. In a separate analysis, PGMY09-PGMY11 (PGMY-Gold), a redesigned MY09/11 primer set, was compared with MY-Gold for HPV DNA detection (n = 439). There was very good agreement between the two methods (kappa = 0.83; 95%CI = 0.77-0.88) and surprisingly no significant differences in HPV detection (P = 0.41). In conclusion, we found MY-Gold to be a more sensitive assay for the detection of HPV DNA than MY-Taq. Our data also suggest that studies reporting HPV DNA detection by PCR need to report the type of polymerase used, as well as other assay specifics, and underscore the need for worldwide standards of testing.     

Intermethod variation in detection of human papillomavirus DNA in cervical smears.

In order to investigate the reliability of detection of human papillomavirus (HPV) DNA in cervical smears, we have compared the performance of two HPV PCR systems, the CPI/IIG and MY09/11 primer-mediated PCRs and the Hybrid Capture System HPV DNA detection test (hybrid capture assay), in detecting HPV DNA in cervical smears. We also included in our study the MY09/11B PCR plus SHARP (solution hybridization assay for PCR products) Signal System. This SHARP Signal System was recently developed to detect MY09/11B-generated biotinylated PCR products. The detection rate of the hybrid capture assay was lower than those of the CPI/IIG and MY09/11 PCRs and the MY09/11B PCR plus SHARP Signal System. The detection rates of the CPI/IIG PCR and the MY09/11B PCR plus SHARP Signal System were similar and higher than that of the conventional MY09/11 PCR system. The agreement beyond chance of the PCR methods was nearly perfect (kappa value between 0.82 and 0.84). The agreement beyond chance of the hybrid capture assay and the PCR methods was fair to good (kappa value between 0.64 and 0.70). The systems detected HPV DNA in different but overlapping sets of smears. Our results indicate that each of the detection methods alone underestimates the prevalence of HPV.     

Multiple HPV genotypes in cervical carcinomas: improved DNA detection and typing in archival tissues.

BACKGROUND: Human papillomaviruses (HPV) have been considered to be the necessary and central agents of cervical carcinoma. OBJECTIVE: The aim of this study was to determine the prevalence and genotypes of HPV in archival cervical carcinomas. STUDY DESIGN: The study included 152 paraffin-embedded, formaldehyde-fixed cervical carcinoma specimens. To improve the detection and typing of HPV in archival tissues, we conducted a comprehensive study in which, polymerase chain reaction (PCR)-based methods using E7 type-specific (TS) and L1 modified general primers (MY11/GP6+ and GP5+/GP6+) were employed. RESULTS: Overall HPV prevalence was 98% in the cervical carcinomas. HPV 16 was detected in 66% of the tumors, HPV 18 in 22%, HPV 31 in 13%, HPV 33 in 9%, and HPV 58 in 9%. Notably, multiple HPV types were present in 44 (28.9%) of the 152 cervical carcinomas. The most common co-infections were HPV types 16/18 (12 cases), followed by HPV types 16/31 (7 cases). Additionally, HPV 18 was more frequent in adenocarcinomas and adenosquamous carcinomas (86%) than in squamous cell carcinomas (15.8%) (P = 0.0002). CONCLUSIONS: The combination of L1 general primers and E7 type-specific primers can be of use in detecting HPV DNA in archival tissues. The present study showed a high frequency of multiple HPV infections in cervical carcinomas. Hence, relevant HPV typing information in cervical carcinoma is very important for further HPV vaccine design and application.