Pierre Forest
Université de Montréal
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Journal of Clinical Microbiology | 2006
François Coutlée; Danielle Rouleau; Patrick Petignat; Georges Ghattas; Janet Kornegay; Peter Schlag; Sean Boyle; Catherine Hankins; Sylvie Vézina; Pierre Côté; John Macleod; Hélène Voyer; Pierre Forest; Sharon Walmsley; Eduardo L. Franco
ABSTRACT 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.
The Journal of Infectious Diseases | 2004
Joséphine Aho; Catherine Hankins; Cécile Tremblay; Pierre Forest; Karina Pourreaux; Fabrice Rouah; François Coutlé
We investigated the role of human papillomavirus (HPV) type 52 polymorphism in the persistence of HPV infection, which is a predictor for cervical lesions. Cervical samples obtained at 6-month intervals were tested for HPV-52 in 1055 women; 41, 12, and 58 women had persistent, transient, and unclassified HPV-52 infections, respectively. HPV-52 isolates were analyzed by polymerase chain-reaction sequencing of the long control region (LCR), E6, and E7 genes. Although age (odds ratio [OR], 0.90 [95% confidence interval [CI], 0.81-0.99]), nonprototypic LCR (OR, 9.26 [95% CI, 2.1-41.7]), and E6 variant (OR, 7.04 [95% CI, 1.4-37]) were associated, in univariate analysis, with the persistence of HPV-52 infection, a nonprototypic LCR variant was the only independent predictor of it (OR, 14.1 [95% CI, 1.1-200]). In the latter variants, the loss of a binding site for a repressor of HPV expression was associated with the persistence of HPV infection (OR, 7.25 [95% CI, 1.67-31.25]).
The Journal of Infectious Diseases | 2004
Simon Gagnon; Catherine Hankins; Cécile Tremblay; Pierre Forest; Karina Pourreaux; François Coutlée
BACKGROUND Genetic polymorphism in human papillomavirus (HPV)-33 and -35 was investigated in 1055 sexually active women (732 human immunodeficiency virus [HIV] seropositive and 323 HIV seronegative). METHODS Consecutive genital specimens obtained at 6-month intervals were screened for HPV-33 and -35 by use of MY09-MY11. HPV-33 and -35 isolates from 95 women were analyzed by polymerase chain reaction sequencing of the long control region (LCR), E6, and E7. RESULTS For HPV-33, 101 (20%) of 506 nucleotides in the LCR were variable, compared with 10 (2.1%) of 483 nucleotides in E6 (P<.001) and 6 (1.9%) of 324 nucleotides in E7 (P<.001). For HPV-35, the proportion of variable nucleotide sites was similar between the LCR and both E6 (P=.54) and E7 (P=.33). The presence of a 78-base pair deletion in HPV-33 (relative risk [RR], 1.8 [95% confidence interval [CI], 1.2-2.7]) and the presence of nonsynonymous E7 variations in HPV-35 (RR, 2.6 [95% CI, 1.4-4.6]) were associated with persistence. When the data for HPV-33 and -35 were combined, infection by HPV isolates with nonsynonymous E7 variations (RR, 2.3 [95% CI, 1.6-3.4]; P=.001) and ethnicity (P=.04) were associated with persistence, whereas age (P = .14) and HIV infection/CD4 cell count status (P=.12) were not significantly associated with persistence, by logistic regression analysis. CONCLUSION HPV-33 and -35 polymorphism was different between types and was associated with persistence of HPV infection.
The Journal of Infectious Diseases | 2003
Joséphine Aho; Catherine Hankins; Cécile Tremblay; Franz Lang; Pierre Forest; Karina Pourreaux; Fabrice Rouah
Human papillomavirus (HPV) type 52 DNA was detected in cervicovaginal lavage samples from 91 (12.4%) of 732 human immunodeficiency virus (HIV)-seropositive women and 23 (7.1%) of 323 HIV-seronegative women (P=.0004). HIV infection was an independent predictor for HPV-52 infection when controlling for age and sexual activity (odds ratio, 2.21; 95% confidence interval, 1.30-3.75: P=.003). We describe the genomic polymorphism of 114 HPV-52 isolates. Long control region (LCR) mutations defined 27 HPV-52 variants. Nearly 32% of HPV-52 isolates carried deletions in the LCR. E6 and E7 mutations defined 17 and 9 variants, respectively. Five nonsynonymous E6 mutations were clustered from amino acids 92 to 94, near the putative p53 binding area. White women were more frequently infected by the prototype strain than were women of African descent (P=.0001). The genetic diversity of HPV-52 should facilitate the investigation of the role of genomic variations in cervical disease.
Journal of Clinical Microbiology | 2011
Véronique Legault; Ann N. Burchell; Patricia Goggin; Belinda Nicolau; Paul Brassard; Julie Guénoun; Pierre Forest; Marie-Hélène Mayrand; Eduardo L. Franco; François Coutlée
ABSTRACT A generic human papillomavirus (HPV) probe assay was compared to the Linear Array to detect HPV DNA in 1,013 clinical specimens. The sensitivity, specificity, and negative predictive value of the assay were 99.5% (95% confidence interval [CI], 98.4% to 99.9%), 58.6% (95% CI, 53.9% to 63.1%), and 98.9% (95% CI, 96.5% to 99.8%), respectively. This assay conveniently identifies HPV-positive specimens.
Journal of Clinical Microbiology | 2000
Marie-Hélène Mayrand; François Coutlée; Catherine Hankins; Normand Lapointe; Pierre Forest; Manon de Ladurantaye; Michel Roger
Cancer Detection and Prevention | 2005
Anita Koushik; Anirban Ghosh; Eliane Duarte-Franco; Pierre Forest; Hélène Voyer; Greg Matlashewski; François Coutlée; Eduardo L. Franco
Journal of Clinical Microbiology | 1999
Michel Roger; Marie-Claude Faucher; Pierre Forest; Pierre St-Antoine; François Coutlée
Journal of Medical Virology | 2005
Simon Gagnon; Catherine Hankins; Cécile Tremblay; Karina Pourreaux; Pierre Forest; Fabrice Rouah; François Coutlée
FEBS Journal | 1994
Daniel Auclair; B. Franz Lang; Pierre Forest