Development of a PCR-based line probe assay for identification of fungal pathogens.

نویسندگان

  • C Martin
  • D Roberts
  • M van Der Weide
  • R Rossau
  • G Jannes
  • T Smith
  • M Maher
چکیده

We report on a reverse-hybridization line probe assay (LiPA) which when combined with PCR amplification detects and identifies clinically significant fungal pathogens including Candida, Aspergillus, and Cryptococcus species. DNA probes have been designed from the internal transcribed-spacer (ITS) regions of Candida albicans, Candida parapsilosis, Candida glabrata, Candida tropicalis, Candida krusei, Candida dubliniensis, Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus versicolor, Aspergillus nidulans and Aspergillus flavus. The probes were incorporated into a LiPA for detection of biotinylated ITS PCR products, and the specificity of the probes was evaluated. We established LiPA detection limits for ITS 1 and for full ITS amplicons for genomic DNA from C. albicans, A. fumigatus, and C. neoformans. Further evaluation of the LiPA was carried out on clinical fungal isolates. One hundred twenty-seven isolates consisting of dimorphic yeasts and dermatophytic and filamentous fungi were tested by the LiPA, which correctly identified 77 dimorphic yeasts and 23 of the filamentous isolates; the remaining 27 isolates represented species of fungi for which probes were not included in the LiPA. The fungal-PCR-LiPA technology was applied to blood samples inoculated with Candida cells which were pretreated by minibead beating to mechanically disrupt the cells, with the DNA extracted by either a previously described guanidium thiocyanate-silica method or the commercially available QIAmp tissue kit. PCR amplification of the extracted DNA and subsequent DNA probe hybridization in the LiPA assay yielded detection limits of 2 to 10 cells/ml. An internal standard control was included in the PCR amplification to monitor for PCR inhibition. This fungal PCR-LiPA assay is robust and sensitive and can easily be integrated into a clinical-testing laboratory with the potential for same-day diagnosis of fungal infection.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Development, comparison, and validation of real-time and conventional PCR tools for the detection of the fungal pathogens causing brown spot and red band needle blights of pine.

Dothistroma pini, D. septosporum, and Lecanosticta acicola are fungal pathogens that cause severe foliage diseases in conifers. All three pathogens are listed as quarantine organisms in numerous countries throughout the world and, thus, are subject to specific monitoring. Detection and identification of these pathogens still often relies on cumbersome and unsatisfactory methods that are based u...

متن کامل

Reverse line blot hybridization assay for identification of medically important fungi from culture and clinical specimens.

We evaluated a combined panfungal PCR-reverse line blot (RLB) hybridization assay based on internal transcribed spacer 1 (ITS1) and ITS2 region polymorphisms to identify 159 Candida, Cryptococcus neoformans, and Aspergillus isolates (22 species). Its utility to identify fungal pathogens directly from 27 clinical specimens was also determined. ITS sequence analysis was performed to resolve discr...

متن کامل

Use of cost effective and rapid molecular tools for identification of Candida species, opportunistic pathogens

Background and Purpose :Candidiasis is a widespread fungal infection caused by different Candida species. Rapid identification of Candida species in clinical laboratory is becoming increasingly important since the identification and discrimination of ethological agents for early treatment. We aimed at molecular identification of commonly Candida species isolated from clinical samples by using b...

متن کامل

Detection and identification of fungal pathogens in blood by using molecular probes.

A PCR assay was developed for the detection and identification of Candida and Aspergillus species. The design of the oligonucleotide primer pair as well as the species-specific probes used for species identification was derived from a comparison of the sequences of the 18S rRNA genes of various fungal pathogens. The primers targeted a consensus sequence for a variety of fungal pathogens. The as...

متن کامل

Two in-House One-Step rRT-PCR Assays, Developed for Accurate and Rapid Molecular Identification of Newcastle Disease Virus, on the basis of SYBR Green and Specific TaqMan Probe

Background and Aims: Newcastle disease virus (NDV) is an avian paramyxovirus (A-PMV 1) and one of the major pathogens in poultries. Vaccination is intended to control the disease, nevertheless this virus is a growing threat to the poultry industry. So, early detection of the virus can prevent the spread of illness and avoid huge economic losses. Towards this goal, in this research, we develop...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of clinical microbiology

دوره 38 10  شماره 

صفحات  -

تاریخ انتشار 2000