HPV16 variants in squamous intraepithelial lesions in human immunodeficiency virus-negative and -positive Brazilian women

Emerging evidence supports the role of human papillomavirus (HPV) intratype variations in the development of cervical lesions in immunocompetent women, but few studies investigated HPV16 variants in human immunodeficiency virus (HIV)-positive women. This is the first study in Brazil evaluating HPV16 variants in women with (n = 19) and without (n = 22) HIV infection, as well as cervical lesions. Although non-European variants presented an almost 3-fold increase (13.6% vs. 36.8%) among HIV-positive women, associations between HPV16 variants and HIV infection did not reach statistical significance (Fisher's exact test, p = 0.15). No associations were found between non-European variants and HSIL (Fisher's exact test, p = 0.41), although a significant association was observed between European variants and HSIL among HIV-negative women (Fisher's exact test, p = 0.01). In conclusion, in HIV-negative women the HPV16 European variants seem to influence the occurrence of HSIL, whereas in HIV-positive women, similar roles are atributted to both variants.     

Human papillomavirus type-16 variants in Quechua aboriginals from Argentina

Cervical carcinoma is the leading cause of cancer death in Quechua indians from Jujuy (northwestern Argentina). To determine the prevalence of HPV-16 variants, 106 HPV-16 positive cervical samples were studied, including 33 low-grade squamous intraepithelial lesions (LSIL), 28 high-grade squamous intraepithelial lesions (HSIL), 9 invasive cervical cancer (ICC), and 36 samples from women with normal colposcopy and cytology. HPV genome variability was examined in the L1 and E6 genes by PCR-hybridization. In a subset of 20 samples, a LCR fragment was also analyzed by PCR-sequencing. Most variants belonged to the European branch with subtle differences that depended on the viral gene fragment studied. Only about 10% of the specimens had non-European variants, including eight Asian-American, two Asian, and one North-American-1. E6 gene analysis revealed that 43% of the samples were identical to HPV-16 prototype, while 57% corresponded to variants. Interestingly, the majority (87%) of normal smears had HPV-16 prototype, whereas variants were detected mainly in SIL and ICC. LCR sequencing yielded 80% of variants, including 69% of European, 19% Asian-American, and 12% Asian. We identified a new variant, the Argentine Quechua-51 (AQ-51), similar to B-14 plus two additional changes: G7842-->A and A7837-->C; phylogenetic inference allocated it in the Asian-American branch. The high proportion of European variants may reflect Spanish colonial influence on these native Inca descendants. The predominance of HPV-16 variants in pathologic samples when compared to normal controls could have implications for the natural history of cervical lesions.     

Molecular variants of HPV type 16 E6 among Mexican women with LSIL and invasive cancer.

BACKGROUND: Cervical cancer is the second most common cancer in women worldwide. Infection with human papillomavirus (HPV) 16 is an important risk factor associated with cervical cancer, more than 50% of cervical cancer tissues have DNA of HPV 16. Intratypic variants have been reported, although they differ in prevalence, biological and biochemical properties, their implication in the aetiology of cervical cancer is still uncertain. OBJECTIVE: To identify HPV type 16 E6 variants among Mexican women with diagnosis of low-grade squamous intraepithelial lesion (LSIL) or invasive cancer (IC). STUDY DESIGN: Forty HPV16-positive samples were included, 15 were from women with LSIL, 25 from women with IC; 610 pb from the E6 gene were amplified by PCR and the variant status subsequently determined by hybridization with 27 biotinilated probes. Statistical analysis was performed with chi2, odds ratio (OR). RESULTS: In the LSIL group we only found ten (66%) EP and five (33%) EP350G variants. In the IC group, four variants were found; 11 (44%) AA, seven (28%) EP, six (24%) EP350G, one (4%) Af2. Comparison of the frequency of variants differed from EP in both groups of patients (P=0.01) with an odds ratio (OR) of 5.14 (CI 95% [1.07-26.56]). CONCLUSION: This study demonstrates an association between HPV type 16 variants different from prototype (EP) and invasive cervical cancer.     

LSIL biopsies after HSIL smears. Correlation with high-risk HPV and greater risk of HSIL on follow-up

Can the risk associated with a high-grade cervical smear be disregarded when followed by a low-grade biopsy? We examined the distribution of human papillomavirus (HPV) types in such cases to see whether they segregated preferentially with low-risk or high-risk viruses and compared the distribution with that reported in the literature for women with high-grade squamous intraepithelial lesions (HSILs) and low-grade squamous intraepithelial lesions (LSILs). We identified 48 cases of HSIL smears with corresponding LSIL biopsy specimens. Biopsy specimens were tested and typed for HPV by polymerase chain reaction amplification with consensus primers followed by restriction fragment length polymorphism analysis, and HPVs were scored as low-risk or high-risk types. Thirty-seven cases scored positive for HPV DNA: 2 for low-risk HPV types, 17 for high-risk types, and 18 for types of unknown oncogenicity. The prevalence of high-risk HPV was significantly higher than that of low-risk HPV. There was a higher rate of high-risk HPV than that seen in historic unselected LSIL cases. Cases of HSIL cytology/LSIL histology represent a group distinct from unselected LSILs by virtue of their higher prevalence of high-risk HPV types and, therefore, warrant closer clinical follow-up.     

Distribution of human papillomavirus genotypes in women with high-grade cervical intraepithelial lesions and cervical carcinoma and analysis of human papillomavirus-16 genomic variants

AimTo analyze the distribution of high-risk human papillomavirus (HR-HPV) genotypes and the diversity of HPV-16 genomic variants in Croatian women with high-grade squamous intraepithelial lesions (HSIL) and cervical carcinoma.MethodsTissue biopsy specimens were obtained from 324 women with histopathologically confirmed HSIL or cervical carcinoma, 5 women with low-grade SIL, and 49 women with negative histopathology. HR-HPV DNA was detected with Ampliquality HPV-type nucleic-acid hybridization assay, which identifies 29 different HPV genotypes. HPV-16 genomic variants were analyzed by an in-house sequencing.ResultsThe most common HPV type in women with HSIL was HPV-16, detected in 127/219 (57.9%) specimens. HPV-16 was also the dominant type in squamous cell cervical carcinoma (46/69 or 66.7%) and in adenocarcinoma (18/36 or 50.0%). Out of 378 patients, 360 had HR-HPV (282 single infections and 79 multiple infections), 3 (0.8%) patients had low-risk HPV, and 15 (4%) tested negative. HPV-16 variants were determined in 130 HPV-16 positive specimens, including 74 HSIL and 46 carcinoma specimens. In HSIL specimens, 41 distinct variants were found, 98.6% belonging to the European branch and 1.4% belonging to the African branch. In cervical carcinoma specimens, 95% isolates grouped in 41 variants belonging to the European branch, one isolate (2.5%) belonged to the North American, and one (2.5%) to the Asian-American branch.ConclusionHPV-16, mainly belonging to the European branch, was the most frequent HPV genotype in women from Croatia with histologically confirmed HSIL and cervical cancer.

Cervical cancer is the second leading cause of death in women in low-income countries (1). Persistent infection with particular human papillomavirus (HPV) genotypes is a necessary but not a sufficient requirement for the development of cervical cancer (2). HPV DNA is detected worldwide in nearly all specimens of invasive cervical cancer, including squamous cell carcinomas, adenocarcinomas, and the majority (>95%) of immediate cervical cancer precursors (3). An epidemiological study by Bosch et al (4) has shown that the most common HPV genotypes in HSIL and squamous cell carcinomas were HPV-16, HPV-18, HPV-31, HPV-33, HPV-35, HPV-45, HPV-52, and HPV-58, with a combined worldwide relative contribution of 91% and the predominant role of HPV-16, HPV-18, and HPV-45 in cervical adenocarcinoma.HPV genomic variants are defined as the viruses that vary by 2% or less in specified regions of the genome, and some display different oncogenicity (5). HPV-16 heterogeneity has been extensively investigated (6-12), and HPV-16 genomic variants have been identified to belong to five main branches: European, Asian-American, two African branches, and an Asian branch (13). Two subsequent studies expanded these classifications and reported a new branch: North American 1 (14,15).Epidemiological studies have shown that non-European HPV-16 variants may promote viral persistence and disease progression (16-19). HPV-16 E6 variants, including the European HPV-16 T350G variant in the E6 gene, were detected up to 20 times more often in patients with high-grade cervical disease compared with controls. A novel HPV-16 variant, identified in Croatia, harboring a 63-bp in-frame duplication in the E1 gene, was presumed to be of reduced oncogenicity (11).According to the several national or regional studies in women with normal and abnormal cytology, HPV-16 is the most common high-risk genotype in Croatian women (20-27). However, none of these studies involved HPV genotyping in tissue specimens, and the majority were performed in general population with a small number of women with histologically confirmed HSIL or cervical cancer. The genomic diversity of high-risk HPV genotypes in Croatia has not been studied to date. On the other hand, recommended, non-mandatory, free-of-charge, nine-valent HPV vaccine is available in Croatia and is intended for vaccination of both women and men aged 14 to 25 years (28).The aims of this study were to analyze the distribution of high-risk HPV genotypes (HR-HPV) in women with histologically confirmed HSIL and cervical carcinoma and to analyze the genomic diversity of HPV 16 in HSIL in comparison with invasive cervical cancer.     

Study of viral integration of HPV-16 in young patients with LSIL

AIMS: To investigate the physical status of human papillomavirus 16 (HPV-16) in low grade squamous intraepithelial lesions (LSILs) as a means of determining the percentage of viral integration. METHODS: Ninety two LSIL/HPV positive Thin Prep(TM) samples were initially tested for the E6 gene by the polymerase chain reaction (PCR) to identify the HPV-16 virus. To avoid false positive results, the specificity of the bands obtained from PCR was confirmed by Southern blot hybridisation with internal oligonucleotide probes. Next, a PCR screen for the E2 gene was performed to identify those samples in which the virus was integrated. Viral integration was detected in just over half of them. RESULTS: Twenty of the 92 samples were HPV-16 positive, as shown by PCR for the E6 gene. Southern blot analysis confirmed that 13 of these samples were positive for the viral E6 gene. Thus, viral integration was detected in just over a half of the samples positive for HPV-16. CONCLUSIONS: These data show that HPV-16 integration occurs in a subset of LSILs. The measurement of HPV-16 integration would be a helpful complementary tool for cytological evaluation in primary cervical screening to identify those patients at risk of developing high grade squamous intraepithelial lesions and cervical cancer.     

Serological detection of human papillomavirus type 16 infection in human immunodeficiency virus (HIV)-positive and high-risk HIV-negative women

Serial measurement of antibodies has not been used to provide evidence of active viral replication of human papillomavirus (HPV). Serum specimens from sequential study visits contributed by 642 human immunodeficiency virus (HIV)-positive and 116 HIV-negative participants enrolled in the Women's Interagency HIV Study were used to detect significant rises in HPV type 16 (HPV-16) antibody levels. Factors associated with a significant rise were identified using multivariable logistic regression models with generalized estimating equations. Among HIV-positive women, 8.3% of 1,997 pairs showed antibody rises, compared to 6.1% of 361 pairs among HIV-negative women (P = 0.191). For HIV-positive women, rises were associated with current (odds ratio [OR], 23.4; P < 0.001) or past (OR, 8.9; P < 0.001) HPV-16 infection relative to never being HPV-16 infected and with CD4+ cell counts (OR per 100-cell increase, 0.8; P < 0.001) but not with sexual behavior. For HIV-negative women, rises were associated with past (OR, 10.9; P = 0.033) HPV-16 infection relative to no HPV-16, current cigarette smoking (OR, 5.0; P = 0.029) relative to no smoking history, and having 6 to 10 lifetime sexual partners compared to 0 to 5 partners (OR, 9.9; P = 0.036). Serial measurement of HPV-16 serum antibodies is a useful tool for identifying active HPV-16 viral replication. Rises among HIV-positive women may more often result from reactivation of a latent HPV infection in the context of HIV-induced immunosuppression, while rises among HIV-negative women may more often result from reinfection with HPV.     

Atypical immature metaplasia (AIM) of the cervix: is it related to high-grade squamous intraepithelial lesion (HSIL)?

Atypical immature metaplasia (AIM) is a poorly characterized cervical lesion with uncertain biological and clinical significance. AIM shares some, but not all, morphological features of squamous intraepithelial lesions (SILs). SILs are characterized by human papillomavirus (HPV) positivity and increased cellular proliferation, but these features have not been fully evaluated in AIM. Genomic DNA was extracted from 27 microdissected cervical biopsy specimens diagnosed as AIM. HPV DNA was detected by polymerase chain reaction (PCR), using two different sets of L1 gene consensus primers. HPV types were identified by sequence analysis of PCR products and comparison with published HPV sequences. The cell proliferation index was assessed by immunohistochemical staining for Ki-67 (MIB-1) antigen and expressed as the percentage of Ki-67-positive cells. Comparison groups included normal cervix (n = 10) and low-grade (LSILs, n = 19) and high-grade squamous intraepithelial lesions (HSILs, n = 11). Intermediate- or high-risk HPV DNA was detected in 67% (18 of 27) of AIM cases. Low-risk HPV DNA was not detected in any of the specimens. The Ki-67 index in AIM (mean, 33.0 +/- 20.3; median, 29) was comparable to that of LSILs (mean, 21.4 +/- 4.6; median, 21) and was significantly higher than that of normal cervix (mean, 11.0 +/- 2.1; median, 11) (P< .01) and lower than that of HSILs (mean, 60.4 +/- 13.2; median, 60) (P < .01). Of the cases with available follow-up, HPV-positive AIMs were significantly more likely to have a concurrent or subsequent diagnosis of typical HSIL (12 of 15, 80%) than HPV-negative AIMs (one of six, 45%) (P = .014). The wide range of Ki-67 indices and variable HPV status in AIM suggest that AIM represents a heterogeneous group of lesions including bona fide HSILs (high-risk HPV-positive, high Ki-67 index), antecedents (precursors?) of HSILs (high-risk HPV-positive, low to moderate Ki-67 index), and benign reactive conditions (HPV-negative, variable Ki-67 index). HPV testing may be useful in the assessment of atypical epithelial proliferations of the cervix for which a diagnosis of AIM is considered.     

Human papillomavirus 16 E6, L1, L2 and E2 gene variants in cervical lesion progression

The human papillomavirus (HPV) 16 E6 genome variant 350G has been found to be more prevalent in women with persistent infection and cervical disease progression than the HPV16 E6 prototype 350T. In this study, we examined whether women who progressed to a high-grade lesion, yet were infected with the prototype 350T, showed variants in other HPV genes such as L1, L2 and E2. Although we detected variants within these genes, they could not explain this phenomenon. Indeed they correlated similarly with variant 350G and prototype 350T. These data indicate that polymorphisms in HPV16 E6 rather than in the other analyzed genes play a role in determining the risk for cervical lesion progression and that additional factors are likely to be required as well.     

Monoclonality and surface lesion‐specific microsatellite alterations in premalignant and malignant neoplasia of uterine cervix: a local field effect of genomic instability and clonal evolution

Invasive squamous carcinoma of the uterine cervix (CC) arises from sequential progression of low‐grade (L) and high‐grade (H) squamous intraepithelial lesions (SILs). In clinical observations, these lesions are frequently found as synchronous multiple foci. The nature and evolutionary mechanism of these lesions are largely unknown. We have performed allelotyping of three 3p markers (at 3p14, 3p22–24, and 3p25) on 22 LSILs and 15 HSILs microdissected from patients with multiple (n = 21) or uniform (n = 6) cervical lesions. The results were analyzed together with our previous allelotyping of 57 deeply invasive CCs. Loss of heterozygosity at one of the three markers was observed in 23%, 27%, and 31% of LSILs, HSILs, and CCs, respectively. Frequent and early allelic loss was noted (in 30% of LSILs and 50% of HSILs) at 3p14, which may harbor tumor suppressor genes involved in early stages of cervical carcinogenesis. A high frequency of microsatellite alteration (MA) was found in LSIL (41%) and HSIL (67%) but not in CC (5.3%). In particular, MA was more frequently found in low‐grade lesions in association with invasive cancers (75%, 6/8) than in those associated with SILs (29%, 4/14) (P < 0.05). Together with the finding of a monoclonal origin of premalignant and malignant cervical lesions, the present results allow us to propose a model of local field effect of genomic instability that progressively affects the clonal evolution of SIL of uterine cervix. Genes Chromosomes Cancer 24:127–134, 1999. © 1999 Wiley‐Liss, Inc.     

广州东部妇女宫颈人乳头瘤病毒16型感染及基因分析

目的 研究广州东部妇女中人乳头瘤病毒16型(HPV-16)宫颈感染分布,分析其早基因E6/E7的多态性,分析L1和E6基因定量与病程的关系.方法 通过导流杂交基因芯片技术检测宫颈脱落细胞的HPV-16感染;通过特异性扩增获取病毒早基因E6/E7序列,克隆测序并进行多态性分析;荧光定量PCR技术对E6基因和L1基因进行定量分析.结果 806例宫颈脱落细胞样本中HPV-16感染阳性36例(4.5%),其中18例(50.0%)宫颈细胞发生高度以上病变;7例(4例低度或以下病变,3例高度以上病变或浸润癌)阳性标本得到E6/g7序列有15个位点分别出现变异;高度病变组(A组,11例)与低度或以下病变组(B组,14例)的L1基因和E6基因定量数据对数值均有显著差异(P<0.05),但L1/E6比值差异无统计学意义(P=0.19).结论 本地区在17～62岁妇女中HPV-16感染阳性发生率约4.5%,50.0%发生高度以上宫颈病变,本研究显示病毒基因拷贝数与宫颈病变程度可能有关,L1/E6比值未能提示病毒整合的发生.     

Human papillomavirus type 16 variants in cervical cancer from an admixtured population in Brazil

Several studies indicate that molecular variants of HPV-16 have different geographic distribution and risk associated with persistent infection and development of high-grade cervical lesions. In the present study, the frequency of HPV-16 variants was determined in 81 biopsies from women with cervical intraepithelial neoplasia grade III or invasive cervical cancer from the city of Belem, Northern Brazil. Host DNAs were also genotyped in order to analyze the ethnicity-related distribution of these variants. Nine different HPV-16 LCR variants belonging to four phylogenetic branches were identified. Among these, two new isolates were characterized. The most prevalent HPV-16 variant detected was the Asian-American B-2, followed by the European B-12 and the European prototype. Infections by multiple variants were observed in both invasive cervical cancer and cervical intraepithelial neoplasia grade III cases. The analysis of a specific polymorphism within the E6 viral gene was performed in a subset of 76 isolates. The E6-350G polymorphism was significantly more frequent in Asian-American variants. The HPV-16 variability detected followed the same pattern of the genetic ancestry observed in Northern Brazil, with European, Amerindian and African roots. Although African ancestry was higher among women infected by the prototype, no correlation between ethnical origin and HPV-16 variants was found. These results corroborate previous data showing a high frequency of Asian-American variants in cervical neoplasia among women with multiethnic origin.     

Analysis of human papillomavirus type-16 variants in Italian women with cervical intraepithelial neoplasia and cervical cancer

Human papillomavirus type 16 (HPV-16) classes (E, AA, As, Af1, Af2) and their variants have different geographic distribution and different degrees of association with cervical lesions. This study was designed to examine HPV-16 variants among Italian women and their prevalence in case patients (affected by invasive cervical carcinoma or cervical intraepithelial neoplasia grade 2-3 and cervical intraepithelial neoplasia grade 1), versus control subjects with normal cervical epithelium (controls). A total of 90 HPV-16 positive cervical samples from women of Italian Caucasian descent have been tested, including 36 invasive cervical carcinomas, 21 with cervical intraepithelial neoplasias grade 2-3, 17 with cervical intraepithelial neoplasia grade 1 and 16 controls. HPV-16 was detected with an E6/E7 gene-specific polymerase chain reaction, and variant HPV-16 classes and subclasses were identified by direct nucleotide sequencing of the region coding for the E6 and the E7 oncoproteins, the MY09/11-amplified highly conserved L1 region, and the long control region (LCR). Among the 90 HPV-16 samples, nine viral variants have been identified belonging to the European (Ep-T350 and E-G350) and non-European (AA and Af-1) branches. The E-G350 is the prevalent variant in all analyzed different disease stages being present in 55.5% of ICC, 52.4% of cervical intraepithelial neoplasias 2-3, 47.1% of cervical intraepithelial neoplasia grade 1, and 50.0% of control samples. The non-European variants AA and Af1, rarely detected in control samples, represent 33.3% of all HPV-16 infections in invasive cervical carcinoma (with a peak of 19.4% and 13.9%, respectively), showing a statistically significant increase in frequency in more advanced lesions (chi(2) trend = 7.2; P < 0.05). The prevalence of HPV-16 Ep-T350, however, is higher in controls (43.7%) and in of cervical intraepithelial neoplasia grade 1 (41.2%) than in cervical intraepithelial neoplasia grade 2-3 (28.6%) and in invasive cervical carcinoma (11.1%) cases strongly suggesting lack of progression for pre-neoplastic lesions associated with such variant. The increased frequency of non-European variants in invasive lesions suggests that they are more oncogenic than European variants. This could have implications for future diagnostic and therapeutic strategies.     

The prevalence of HPV-18 and variants of E6 gene isolated from cervical cancer patients in Taiwan.

BACKGROUND: Cervical cancer is the second most common cancer in women worldwide. It has been considered that human papillomavirus (HPV) is associated with cervical cancer. Currently, more than 80 different serotypes of HPV have been characterized and they are divided into low- and high-risk groups. The most common types that lead to cervical cancer are HPV-16 and -18. The viral oncogenes E6 and E7 are associated with the development of cervical cancer. In previous study, the variants of HPV-16 E6 gene have been reported. It suggests that variants may influence the morbidity of carcinogenesis, but the variant study on HPV-18 remains unknown. OBJECTIVES: To identify the variants of integrated HPV-18 E6 gene in the prevalent infection of HPV-18 of cervical cancer patients. STUDY DESIGN: 25 cervical cancer patients were clinically identified and the biopsies were obtained. The infectious HPV types were identified by PCR and Southern blotting analysis. The DNA fragments of the integrated HPV-18 E6 were amplified by PCR and cloned. The nucleotide sequences were obtained by sequencing. RESULTS: The prevalence of HPV infection in our 25 cases was HPV-18 (100%) and 7 out of these 25 cases (28%) were co-infected with HPV-16. The most dominant mutation among 25 tested patients was a silence mutation C183G of the E6 coding region. CONCLUSIONS: The prevalent HPV infectious serotype is HPV-18, which differs from the worldwide prevalent type. The identified HPV-18 E6 variants had a unique silence mutation located on C183G in E6 coding region.     

Evaluation of the detection of human papillomavirus genotypes in cervical specimens by hybrid capture as screening for precancerous lesions in HIV-positive women

Given the frequency and persistence of human papillomavirus (HPV) infection and associated cytological alterations in HIV-1-positive women, the incidence of uterine cervix neoplasm is likely to increase along with patient survival. More appropriate screening programs, which, in addition to Pap smears (PS), also include tests to detect and type HPV, are needed for the early identification of precancerous cervical lesions. This prospective study involved 168 HIV-positive (group A) and 100 HIV-negative women (group B). Cervicovaginal samples were collected for a PS and HPV DNA search. The detected virus was typed as high–intermediate oncogenic risk HPV (HR-HPV) and low-risk HPV (LR-HPV) using hybrid capture (HC) (Murex-Digene) and in-house PCR tests. The HC-detected prevalence of HPV was 111/168 (66%:HR 75.6%) in group A and 15/100 (15%:HR 42.9%) in group B (P < 0.0001). Polymerase chain reaction (PCR) was positive in 91% and 48%, respectively. No significant difference was observed between drug addicts and heterosexual HIV-1-positive women (P = 0.09). HPV was detected in 94% of the 57 HIV-positive women with cytological alterations. HR-HPV was found in 41/49 women with low-grade and 7/8 with high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively). In women with a negative PS, HPV was detected in 57/111 cases (HR 63%) of group A and in 13/98 of group B (6 cases of HR). Of the 54 group A women who underwent biopsy, histology revealed that 41 had LSIL (18 with negative PS, 19 with LSIL, and 4 with HSIL; HR-HPV in 73% and LR-HPV in 17%), nine had HSIL (5 LSIL and 4 HSIL on cytology; HR-HPV in 89% and LR-HPV in 11%), and four were negative (all cytology negative; 3 HR-HPV and 1 LR-HPV). HR-HPV was more frequent as immunodepression worsened. These results show that cytological evaluation alone underestimated histological alterations in 23/50 women (42.6%), whereas the combination of Pap smear and HPV detection reduced this underestimate to 5%. J. Med. Virol. 56:133–137, 1998. © 1998 Wiley-Liss, Inc.     

High-throughput profiling of the humoral immune responses against thirteen human papillomavirus types by proteome microarrays

We have developed microarrays with all eight proteins encoded by 13 different human papillomavirus types associated with anogenital cancer (HPV-16, -18, -31, -33, -35, -45, and -53), genital warts (HPV-6 and -11), or skin lesions (HPV-1, -2, -4, and -5). We analyzed the seroprevalence of antibodies in 546 patients, which had either cervical carcinomas, or precursor lesions, or which were asymptomatic. All patient groups contained sera ranging from high reactivity against multiple HPV proteins to low or no reactivity. Computational analyses showed the E7 proteins of carcinogenic HPV types as significantly more reactive in cancer patients compared to asymptomatic individuals and discriminating between cancer and HSIL or LSIL patients. Antibodies against E4 and E5 had the highest seroprevalence but did not exhibit differential reactivity relative to pathology. Our study introduces a new approach to future evaluation of the overall antigenicity of HPV proteins and cross-reaction between homologous proteins.     

Testing automated liquid-based cytology samples with a manual liquid-based cytology method using residual cell suspensions from 500 ThinPrep cases

We report a technical improvement upon a previously disclosed manual liquid-based cytology (MLBC) method; and, we use the improved method to prepare slides from residual ThinPrep specimens in order to see how often ThinPrep diagnoses correspond to diagnoses derived from exhaustive examination of their parent sample suspensions. Residual cell suspensions from 500 ThinPrep cases comprising (1) 20 low-grade squamous intraepithelial lesions (LSILs); (2) 200 high risk (HR) negatives and 20 ASC-US; and (3) 260 screening cytology specimens were studied. Institutional review committee guidelines allowed us to know diagnoses by groups of specimens, but did not allow us to know individual patient diagnoses, so we could not perform case-by-case matched outcome-comparisons. Cells were concentrated by conventional centrifugation and sedimented into a polymer gel that was then vortex-mixed and converted into a viscous cell-rich suspension. The cell suspension was smeared between two clean glass slides, which were air-dried and stained with the Papanicolaou stain. Two study-sets were created, comprising one slide from each case. Each of the two study sets was examined by two cytopathologists, and discordant diagnoses were adjudicated. Because of the ambiguity involved in the "atypical" (ASC-US, ASC-H, AGC) diagnosis categories, only outcomes at the level of LSIL or greater were recorded. All MLBC SILs were digitally imaged and abnormal slides plus digital images were sent to the laboratory that provided the residual automated liquid-based cytology (ALBC) suspensions. The final diagnoses were confirmed by the laboratory that provided the residual ALBC specimens. MLBC slides of the 20 LSIL cases afforded 2 high-grade squamous intraepithelial lesions (HSILs) and 18 LSILs. Those of the 200 HR-Negatives showed 3 HSILs and 30 LSILs; and those of the 20 HR-ASC-US showed 3 HSILs and 9 LSILs. MLBC slides of the 260 screening cytology specimens showed 1 Carcinoma, 3 HSILs and 20 LSILs; affording 3 HSILs and 14 LSILs more than originally diagnosed. The MLBC method of this report is useful for preparing cell suspensions for cytological examination. Our analytical method was exhaustive and used nearly all of the cell material that was provided to us for analysis; therefore, we conclude that this approach is useful for determining how well ALBC instruments represent their parent sample suspensions. It appears that "rare events" may be overlooked when limited sample aliquots are analyzed by ALBC instruments, and this probably accounts for our increased discovery of SILs by the MLBC method. Also, SILs often present as aggregates of cohesive cells which, if overlooked or ineffectively transferred to ALBC slides, would not be diagnosed.     

Human papillomavirus type 16 variant assignment by pyrosequencing

Polymorphisms in human papillomavirus type 16 (HPV16) result in variants from the prototype sequence which can be designated according to geographic distribution and are broadly classified as European (E), African (Af), Asian (As), or Asian-American (AA). Detection of variants has been used to distinguish persistent HPV16 infection from re-infection in natural history studies, and variants have been associated with an increased risk of cervical disease in some populations. Variant determination usually relies on conventional Sanger sequencing of regions of the viral genome, with the major variant group assignments requiring the sequencing of only seven polymorphic sites spread over a 242-bp region of the E6 gene. We applied pyrosequencing to facilitate rapid sequencing and enable the simultaneous detection of multiple variants. A single-stranded template for pyrosequencing was prepared by amplifying a 314-bp fragment (nt 75-388) with a biotin at the 5'-end of the reverse primer to facilitate strand separation and purification. Polymorphisms at the nucleotide sites 109, 131, 132, 143, 145, 178 and 350 were determined in three separate sequencing reactions, one of which was a multiplex format. Pyrosequencing of 97 HPV16-positive exfoliated cervical samples confirmed the Sanger sequencing results; however pyrosequencing identified additional variants in several samples containing mixed variants.     

Increased secretion patterns of interleukin-10 and tumor necrosis factor-alpha in cervical squamous intraepithelial lesions

Cytokines are released in response to infection of the uterine cervix by high-risk HPV. By using enzyme-linked immunosorbent assay, we measured the levels of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (INF-gamma), interleukin-6 (IL-6), and interleukin-10 (IL-10) in the cervical secretions of 120 cytologically normal or equivocal and 91 abnormal Japanese women. HPV infection of the cervical cells was typed by the LCR-E7 PCR method. The HPV DNA-negative samples were classified as either normal or inflamed, and the HPV DNA-positive samples were classified as HPV positive(+) n-ormal and as low- or high-grade squamous intraepithelial lesions (SILs). Compared with the normal cervices, all of the cytokines tested were elevated in inflamed, HPV+ normal, low-grade SILs (LSIL), and high-grade SILs (HSIL). The level of IL-10 was statistically higher in LSIL, and the level of TNF-alpha was higher in HSIL, relative to the cytokine levels in the inflamed and HPV+ normal samples (P <0.05; Mann-Whitney test). Multivariate analyses confirmed that increased levels of IL-10 were associated with LSIL (relative risk [RR]=3.9, 95% confidence interval [CI]=1.7-8.8) and that increased levels of TNF-alpha (RR=4.6, 95% CI=1.4-15) and age older than 40 years (RR=8.5, 95% CI=1.3-56) were associated with HSIL. The levels of INF-gamma and TNF-alpha (Th1-cytokines) correlated negatively with those of IL-6 and IL-10 (Th2-cytokines) in HPV+ normal and LSIL subjects, whereas no such correlation was observed for HSIL. The up-regulated secretion of IL-10 may inhibit immune responses against HPV infection in early cervical lesions, whereas up-regulated TNF-alpha and uncoordinated cytokine secretion (elevated both Th1 and Th2 cytokines) may reflect impaired or invalid responses in advanced stage lesions. The detection of IL-10 and TNF-alpha in cervical secretions may be a useful indicator of local immune responses and of the stage of the cervical lesions induced by HPV infection.