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Allan Hildesheim

Publications and source records attributed to Allan Hildesheim.

65 records · Page 4Linked to original sources
PubMed2002

Comprehensive analysis of human leukocyte antigen class I alleles and cervical neoplasia in 3 epidemiologic studies.

To comprehensively explore the relationship between human leukocyte antigen (HLA) class I alleles and cervical neoplasia, a subset of participants from 3 large US and Costa Rican cervix studies were typed for HLA class I alleles. Study subjects were women with cervical cancer or high-grade squamous epithelial lesions (HSILs; n=365) or low-grade squamous epithelial lesions (LSILs; n=275) or who were cytologically normal (control subjects; n=681). Allele-disease associations were assessed by logistic regression analysis. Consistent associations across all studies were observed for HLA-CW*0202 with a combined odds ratio of 0.53 (95% confidence interval [CI], 0.29-0.89) for cancer or HSILs and 0.58 (95% CI, 0.37-1.04) for LSILs, compared with control subjects and adjusted for study. This finding supports the hypothesis that a single allele may be sufficient to confer protection against cervical neoplasia. Given the relationship between HLA-C and its receptors on natural killer (NK) cells, a role is proposed for NK function in human papillomavirus infection and cervical neoplasia.

Alleles↗
PubMed2002

Application of IL-5 ELISPOT assays to quantification of antigen-specific T helper responses.

To be able to determine the frequencies of helper-type T lymphocyte (Th) precursors specific for viral or tumor-associated antigens, an ELISPOT assay for IL-5 production was developed. The assay reproducibility was first determined using fresh or cryopreserved peripheral blood mononuclear cells (PBMC) obtained from six normal donors and tested for IL-5 production after 48 h stimulation with phytohemagglutinin (PHA). Both inter-assay (within-subject CV=1.6%) and intra-assay (within-subject CV=0.8%) variabilities were found to be acceptable, and the frequencies of IL-5 secreting cells were comparable in cryopreserved and fresh PBMC of the same donors. The presence and frequency of Th precursor cells to viral capsid L1 protein (viral-like particles, VLP-L1) of human papillomavirus type 16 (HPV-16) in PBMC obtained from seven non-immunized donors and two volunteers immunized with VLP-L1 were then evaluated. Using autologous dendritic cells as antigen-presenting cells (APC) for VLP-L1 in direct 48-h ELISPOT assays, the mean frequency of IL-5 secreting CD4+ T cells was found to be <1/10(5) (negative) in normal donors but was 1/2, 436 and 1/3678 in the two volunteers immunized with VLP-L1. The assay is applicable to monitoring of the frequency of antigen-specific T cells in the peripheral circulation of individuals immunized with HPV-derived antigens. To test the assay utility in the assessment of Th tumor-reactive lymphocytes, we also used it to determine the frequency of the wild-type sequence (wt) p53(22-36) peptide-specific, HLA-DR4-restricted T cells in the bulk CD4+ T cell line. This frequency was 1/33. The ELISPOT assay for IL-5 production can be reliably used to measure Th-type responses in a variety of experimental settings.

Antigens, Viral↗
PubMed2002

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.

Cervix Uteri↗
PubMed2002

Past, present, and future of HPV research: highlights from the 19th International Papillomavirus Conference-HPV2001.

This manuscript summarizes the papers presented at the 19th International Papillomavirus Conference, held in Florianopolis, Brazil, September 1-7, 2001, divided in four main areas: Clinical diagnosis and screening, Epidemiology, Biology and Immunology. It provides an overview of what we know about the biology and life cycle of these viruses, their interaction with human and animal hosts, and the diseases that they cause. Highlights derive from the analysis of more than 500 papers presented at the Conference.

Animals↗
PubMed2002

Host and viral genetics and risk of cervical cancer: a review.

Infection with human papillomaviruses (HPV) is known to play a central role in the development of cervical cancer. Both host and viral genetic factors have been postulated to be important determinants of risk of HPV progression to neoplasia among infected individuals. In this report, we review epidemiological studies that have evaluated the role in cervical cancer pathogenesis of genetic variation in human leukocyte antigen (HLA) genes and in the HPV genome itself. A protective effect of HLA Class II DRB1*13/DBQ1*0603 alleles is the most consistent HLA finding in the published literature. A consistent association between HPV16 non-European variants and risk of disease is also evident from published work. These findings are discussed. Gaps in our understanding and future research needs are also discussed.

Female↗
PubMed2002

Cervical concentrations of interleukin-10 and interleukin-12 do not correlate with plasma levels.

Human papillomavirus (HPV) infects the transformation zone of the cervix and is the primary cause of cervical cancer. The infection is localized to the cervix and mucosal immunity is likely to be an important determinant for viral clearance. Previous studies of immunity to HPV have measured immune markers in the blood, but the relationship of systemic immunity to cervical immunity is poorly understood. In this study of 70 women enrolled in the ASCUS-LSIL Triage Study (ALTS), a clinical trial for management of low-grade cytologic abnormalities of the cervix, we collected paired plasma and cervical secretions to investigate the relationship between cervical concentrations of interleukin-10 (IL-10) and interleukin-12 (IL-12) and plasma levels. Neither IL-10 (p = 0.11), or IL-12 (p = -0.04) nor the ratio of IL-12 to IL-10 (p = 0.06) were correlated between blood and cervical secretions. Except for weak correlations of IL-10 among nonsmokers (p = 0.35. P = 0.019) and those in day 18-27 of their menstrual cycle (p = 0.51, P = 0.015), this lack of correlation persisted in all subgroups defined by genital inflammation or infection, current oral contraceptive use, heme contamination and volume of collected secretions, HPV16 seropositivity, and repeat HPV infection and/or cytologic abnormalities. The lack of correlation and high concentrations in cervical secretions indicate that the cervical IL-10 and IL-12 concentrations exceed what could be expected from blood as a principle source of IL-10 and IL-12 and suggest that cytokine concentrations in cervical secretions are predominantly the result of local cytokine production.

Adult↗
PubMed2002

Can cervicography be improved? An evaluation with arbitrated cervicography interpretations.

OBJECTIVE: The purpose of this study was to estimate the optimal performance of cervicography. We compared an arbitrated cervigram classification with an arbitrated referent diagnosis of cervical neoplasia. STUDY DESIGN: From an initial group of 8460 women, a stratified sample of cervigrams from 3645 women and histologic information from 414 women underwent arbitration. Interobserver agreement was assessed for cervicography and the referent diagnosis. Sensitivity, specificity, and predictive values were estimated for initial and arbitrated cervicography results, compared with the initial and arbitrated referent diagnoses. RESULTS: For the detection of arbitrated high-grade lesions or cancer, arbitrated cervicography yielded an overall sensitivity of 63.9% and a specificity of 93.7%. Significantly higher sensitivity was associated with younger age and age-related visual characteristics. CONCLUSION: Optimization of the cervigram classification improved performance over a single interpretation in this population but suggested the limits of static visual screening.

Colposcopy↗
PubMed2002

Detection and quantitation of human papillomavirus DNA in the plasma of patients with cervical carcinoma.

Human papillomaviruses (HPVs) play a central role in the development of cervical carcinoma. Plasma DNA from 232 patients taken at diagnosis or after treatment for invasive cervical cancer (n = 175) or carcinoma in situ (n = 57) and 60 normal controls were examined for HPV-16 or HPV-18 E7 DNA by conventional and real-time quantitative PCR assays. We found HPV-16 or HPV-18 E7 DNA in 6.9% (11 of 175) of invasive cervical cancer cases (18.1% of cases positive for HPV-16 or HPV-18 at the genital tract), 1.8% (1 of 57) of carcinoma in situ, and 1.7% (1 of 60) of normal controls by conventional PCR. Quantitative PCR identified the highest concentrations of HPV DNA (copy number of HPV/ml of plasma) in patients with invasive cervical cancer (mean, 11,163; median, 183.5), followed by a level of 8 in the single carcinoma in situ case and 0 copies in the normal control initially positive by conventional PCR. HPV DNA can be detected in the plasma of some patients with HPV-positive cervical tumors. It remains to be demonstrated whether quantitative PCR analysis of HPV DNA in plasma may have utility in patients at high risk of recurrent disease.

Adenocarcinoma↗
PubMed2002

Restricted cross-reactivity of hybrid capture 2 with nononcogenic human papillomavirus types.

Hybrid Capture 2 Test using probe B (HC2-B) is a clinical test for the detection of 13 human papillomavirus (HPV) types associated with cervical cancer (oncogenic types), but the potential clinical significance of HC2-B cross-reactivity with untargeted (nononcogenic) HPV types has not been fully evaluated. Thus, HC2-B test results on 954 clinical cervical specimens from a population-based natural history study of HPV in Costa Rica were compared with the data from testing of the same specimens twice by HPV type-specific MY09/MY11 L1 consensus primer PCR. Specimens positive by PCR for single HPV types not targeted by HC2-B were used for determining type-specific cross-reactivity. Effects of cross-reactivity on clinical performance were estimated by calculating sensitivity and specificity with and without cross-reactivity for the detection of high-grade cervical lesions. HC2-B tested positive for single infections by untargeted (cross-reactive) types 11, 53, 61, 66, 67, 70, 71, and 81. Cross-reactivity was strongly associated with PCR signal strength (P(Trend) = 0.0001) and cervical abnormalities (P = 0.0002, Pearson chi(2)). We estimated that HC2-B cross-reactivity resulted in minor changes in screening performance. Clinical sensitivity increased from 84.3% to 87.9%, clinical specificity decreased from 89.6% to 88.1%, and referral rates increased from 11.7% to 13.2% for detection of >or=cervical intraepithelial neoplasia grade 2. The clinical effect of cross-reactivity varied by cytologic interpretation. Among women with normal cytologic interpretations, cross-reactivity significantly improved the accuracy of identifying cytologically nonevident histology of >or=cervical intraepithelial neoplasia grade 2 because of increased sensitivity with maintained specificity. However, among women with equivocal or mildly abnormal cytologic interpretations, cross-reactivity decreased the accuracy of HPV testing because of substantial decreases in specificity. In summary, cross-reactivity with nononcogenic HPV types had little effect on the overall clinical performance of HC2-B as a general screening test, but reduction of cross-reactivity might improve the performance of HPV testing for triage of equivocal or mildly abnormal cytologic interpretations.

Adult↗
PubMed2002

Simultaneous measurement of several cytokines using small volumes of biospecimens.

The role of host immunity in the development of virus-induced cancers has been difficult to elucidate, in part because of our inability to effectively measure multiple immune parameters using available amounts of biological material. The objective of the present study was to validate the use of a newly developed multiplex assay, the LINCOplex assay, for the simultaneous measurement of multiple cytokines [interleukin/(IL)-1beta, IL-2, IL-4, IL-6, IL-8, IL-10, IFN-gamma, and tumor necrosis factor-alpha]. Supernatants obtained from peripheral blood mononuclear cell cultures stimulated with various different mitogens and antigens (including phytohemagglutinin, influenza, tetanus, HPV16 E6 and E7 peptides, and media alone) were selected for study. In total, 750 specimens obtained from 26 participants were tested in replicate using the 8-plex LINCOplex assay (25 micro l of specimen required per well). Every specimen was included in duplicate in a blinded fashion. For some specimens, multiple 2-fold dilutions of the same specimen were included to evaluate the linearity of results. The availability of independently obtained IL-2 and IFN-gamma results from standard single cytokine (simplex) assays allowed for a direct comparison between the LINCOplex results and those obtained from the simplex assays. Spearman correlation coefficients for continuous results, and exact agreement rates and weighted kappa statistics for quartiled variables, were computed to evaluate intra- and interassay agreement. IL-4 levels were consistently below the detectable level of the assay (3 pg/ml) whereas IL-6 and IL-8 levels were consistently above the highest detectable level of the assay (10,000 pg/ml), and these three cytokines were, therefore, not evaluated further. For the remaining five cytokines, excellent intra-assay reproducibility was observed, with Spearman correlation coefficients consistently above 0.90 for all five cytokines. Exact agreement rates ranging from 77.6-90.3% and weighted kappas ranging from 0.81-0.92 were observed. Similar results were observed when analysis was restricted to supernatants obtained from cultures that had been stimulated with HPV16 peptides and when analysis was restricted to supernatants obtained from cultures containing no antigen or mitogen, suggesting that the LINCOplex assay is applicable under conditions where moderate or weak cytokine responses/levels are expected. Linearity of results was observed when dilutions of a single specimen were blindly tested, with the exception of IL-2 and IL-10, where deviations from linearity were sometimes observed. For IL-2 and IFN-gamma, where results from simplex assays were available for comparison, the LINCOplex assay and the simplex assay results agreed well. Spearman correlation coefficients were 0.86 and 0.93 for IL-2 and IFN-gamma, respectively. Exact agreement and weighted kappa values were 68.5% and 0.72 (95% confidence interval, 0.65-0.79), respectively, for IL-2 and 67.3% and 0.73 (95% confidence interval, 0.67-0.80), respectively, for IFN-gamma. These results indicate the applicability of the LINCOplex assay for the simultaneous measurement of multiple cytokines using small amounts of biological material.

Biological Assay↗