Influence of resuspension volume on dry sampling devices taken for human papillomavirus testing: Implications for self-sampling

Abstract

Optimization of technical parameters that influence the performance of human papillomavirus (HPV) testing on self-Taken samples is important. Here, the authors assessed the impact of resuspension volume on the detection of HPV using four validated HPV assays. Two self-sampling devices, FLOQSwabs® and Evalyn® Brushes, were inoculated with dilutions of HPV-16-positive cell line, then resuspended in various volumes of ThinPrep. The influence of vortexing during resuspension was also assessed. At target concentrations around the assay cutoff, larger volumes led to decreased HPV detection. Interestingly, the effect(s) of vortexing differed by the self-sampling device. Resuspension in 5 ml or less may maximize the detection of HPV sequences. Using a proxy of clinical material, the current observations underline the importance of optimizing preanalytical laboratory processes to support high-quality HPV testing of self-samples. METHOD SUMMARY Two commonly used sampling devices, FLOQSwab® and Evalyn® Brush, were used alongside four clinically validated HPV detection assays, Anyplex™ II HPV 28, Aptima HPV, Alinity m HR HPV and cobas® 8800 HPV. The sampling device was submerged into suspensions of an HPV-16-containing cell line (1-2 copies of HPV-16 per cell) at known concentrations, and then resuspended in various volumes of ThinPrep. Cellular concentrations ranged from 105 cells/ml to 103 cells/ml, and resuspension volumes were either 3 ml, 5 ml, 10 ml or 20 ml, to reflect the range of volumes found in the literature. The impact of using a vortex at the time of resuspension was also assessed.