Browsing by Author "Meiring, Tracy"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Open Access
    Clinical validation of the HPVIR high-risk HPV test on cervical samples according to the international guidelines for human papillomavirus DNA test requirements for cervical cancer screening
    (2019-08-22) Gustavsson, Inger; Aarnio, Riina; Myrnäs, Mattias; Hedlund-Lindberg, Julia; Taku, Ongeziwe; Meiring, Tracy; Wikström, Ingrid; Enroth, Stefan; Williamson, Anna-Lise; Olovsson, Matts; Gyllensten, Ulf
    Abstract Background The indicating FTA card is a dry medium used for collection of cervical samples. HPVIR is a multiplex real-time PCR test that detects 12 high-risk human papillomavirus types (hrHPV) and provides single genotype information for HPV16, − 31, − 35, − 39, − 51, − 56, and − 59 and pooled type information for HPV18/45 and HPV33/52/58. The aim of this study was to evaluate whether a strategy with cervical samples collected on the FTA card and subsequently analysed with the HPVIR test complies with the criteria of the international guidelines for a clinically validated method for cervical screening. Methods We performed a non-inferiority test comparing the clinical sensitivity and specificity of the candidate test (FTA card and HPVIR) with a clinically validated reference test (Cobas® HPV test) based on liquid-based cytology (LBC) samples. Two clinical samples (LBC and FTA) were collected from 896 participants in population-based screening. For evaluation of the specificity we used 799 women without ≥ CIN2, and for clinical sensitivity we used 67 women with histologically confirmed ≥ CIN2. The reproducibility was studied by performing inter- and intra-laboratory tests of 558 additional clinical samples. Results The clinical sensitivity and specificity for samples collected on the FTA card and analysed using the HPVIR test were non-inferior to samples analysed with the Cobas® HPV test based on LBC samples (non-inferiority test score, p = 1.0 × 10− 2 and p = 1.89 × 10− 9, respectively). Adequate agreement of > 87% was seen in both the intra- and inter-laboratory comparisons. Conclusions Samples collected on the indicating FTA card and analysed with HPVIR test fulfil the requirements of the international guidelines and can therefore be used in primary cervical cancer screening.
  • Thumbnail Image
    Item
    Open Access
    Next-generation sequencing of cervical DNA detects human papillomavirus types not detected by commercial kits
    (BioMed Central Ltd, 2012) Meiring, Tracy; Salimo, Anna; Coetzee, Beatrix; Maree, Hans; Moodley, Jennifer; Hitzeroth, Inga; Freeborough, Michael-John; Rybicki, Ed; Williamson, Anna-Lise
    BACKGROUND: Human papillomavirus (HPV) is the aetiological agent for cervical cancer and genital warts. Concurrent HPV and HIV infection in the South African population is high. HIV positive (+) women are often infected with multiple, rare and undetermined HPV types. Data on HPV incidence and genotype distribution are based on commercial HPV detection kits, but these kits may not detect all HPV types in HIV+women. The objectives of this study were to (i) identify the HPV types not detected by commercial genotyping kits present in a cervical specimen from an HIV positive South African woman using next generation sequencing, and (ii) determine if these types were prevalent in a cohort of HIV-infected South African women. METHODS: Total DNA was isolated from 109 cervical specimens from South African HIV+women. A specimen within this cohort representing a complex multiple HPV infection, with 12 HPV genotypes detected by the Roche Linear Array HPV genotyping (LA) kit, was selected for next generation sequencing analysis. All HPV types present in this cervical specimen were identified by Illumina sequencing of the extracted DNA following rolling circle amplification. The prevalence of the HPV types identified by sequencing, but not included in the Roche LA, was then determined in the 109 HIV positive South African women by type-specific PCR. RESULTS: Illumina sequencing identified a total of 16 HPV genotypes in the selected specimen, with four genotypes (HPV-30, 74, 86 and 90) not included in the commercial kit. The prevalence's of HPV-30, 74, 86 and 90 in 109 HIV positive South African women were found to be 14.6%, 12.8%, 4.6% and 8.3% respectively. CONCLUSIONS: Our results indicate that there are HPV types, with substantial prevalence, in HIV positive women not being detected in molecular epidemiology studies using commercial kits. The significance of these types in relation to cervical disease remains to be investigated.
  • Thumbnail Image
    Item
    Open Access
    Transkingdom Analysis of the Female Reproductive Tract Reveals Bacteriophages form Communities
    (2022-02-19) Madere, Ferralita S; Sohn, Michael; Winbush, Angelina K; Barr, Breóna; Grier, Alex; Palumbo, Cal; Java, James; Meiring, Tracy; Williamson, Anna-Lise; Bekker, Linda-Gail; Adler, David H; Monaco, Cynthia L
    The female reproductive tract (FRT) microbiome plays a vital role in maintaining vaginal health. Viruses are key regulators of other microbial ecosystems, but little is known about how the FRT viruses (virome), particularly bacteriophages that comprise the phageome, impact FRT health and dysbiosis. We hypothesize that bacterial vaginosis (BV) is associated with altered FRT phageome diversity, transkingdom interplay, and bacteriophage discriminate taxa. Here, we conducted a retrospective, longitudinal analysis of vaginal swabs collected from 54 BV-positive and 46 BV-negative South African women. Bacteriome analysis revealed samples clustered into five distinct bacterial community groups (CGs), and further, bacterial alpha diversity was significantly associated with BV. Virome analysis on a subset of baseline samples showed FRT bacteriophages clustering into novel viral state types (VSTs), a viral community clustering system based on virome composition and abundance. Distinct BV bacteriophage signatures included increased alpha diversity along with discriminant Bacillus, Burkholderia, and Escherichia bacteriophages. Bacteriophage-bacteria transkingdom associations were also identified between Bacillus and Burkholderia viruses and BV-associated bacteria, providing key insights for future studies elucidating the transkingdom interactions driving BV-associated microbiome perturbations. In this cohort, bacteriophage-bacterial associations suggest complex interactions, which may play a role in the establishment and maintenance of BV.