Accession Number:

ADA614802

Title:

Direct Comparison of the Histidine-rich Protein-2 Enzyme-linked Immunosorbent Assay (HRP-2 ELISA) and Malaria SYBR Green I Fluorescence (MSF) Drug Sensitivity Tests in Plasmodium falciparum Reference Clones and Fresh ex vivo Field Isolates from Cambodia

Descriptive Note:

Journal article

Corporate Author:

ARMY INST OF SURGICAL RESEARCH FORT SAM HOUSTON TX

Report Date:

2013-07-12

Pagination or Media Count:

12.0

Abstract:

Background Performance of the histidine-rich protein-2 enzyme-linked immunosorbent assay HRP-2 ELISA and malaria SYBR Green I fluorescence MSF drug sensitivity tests were directly compared using Plasmodium falciparum reference strains and fresh ex vivo isolates from Cambodia against a panel of standard anti-malarials. The objective was to determine which of these two common assays is more appropriate for studying drug susceptibility of immediate ex vivo IEV isolates, analysed without culture adaption, in a region of relatively low malaria transmission. Methods Using the HRP-2 and MSF methods, the 50 inhibitory concentration IC50 values against a panel of malaria drugs were determined for P. falciparum reference clones W2, D6, 3D7 and K1 and 41 IEV clinical isolates from an area of multidrug resistance in Cambodia. Comparison of the IC50 values from the two methods was made using Wilcoxon matched pair tests and Pearson s correlation. The lower limit of parasitaemia detection for both methods was determined for reference clones and IEV isolates. Since human white blood cell WBC DNA in clinical samples is known to reduce MSF assay sensitivity, SYBR Green I fluorescence linearity of P. falciparum samples spiked with WBCs was evaluated to assess the relative degree to which MSF sensitivity is reduced in clinical samples. Results IC50 values correlated well between the HRP-2 and MSF methods when testing either P. falciparum reference clones or IEV isolates against 4-aminoquinolines chloroquine, piperaquine and quinine and the quinoline methanol mefloquine Pearson r 0.85-0.99 for reference clones and 0.56-0.84 for IEV isolates, whereas a weaker IC50 value correlation between methods was noted when testing artemisinins against reference clones and lack of correlation when testing IEV isolates. T

Subject Categories:

  • Medicine and Medical Research
  • Microbiology
  • Pharmacology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE