par Van Campenhout, Claude ;De Mendonça, Ricardo ;Alexiou, Barbara ;De Clercq, Sarah ;Racu, Marie-Lucie ;Royer-Chardon, Claire ;Rusu, Stefan ;Van Eycken, Marie ;Artesi, Maria;Durkin, Keith ;Mardulyn, Patrick ;Bours, Vincent;Decaestecker, Christine ;Remmelink, Myriam ;Salmon, Isabelle ;D'Haene, Nicky
Référence The Journal of molecular diagnostics, 23, 9, page (1065-1077)
Publication Publié, 2021
Référence The Journal of molecular diagnostics, 23, 9, page (1065-1077)
Publication Publié, 2021
Article révisé par les pairs
Résumé : | Implementation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in the daily practice of pathology laboratories requires procedure adaptation to formalin-fixed, paraffin-embedded (FFPE) samples. So far, one study reported the feasibility of SARS-CoV-2 genome sequencing on FFPE tissues with only one contributory case of two. This study optimized SARS-CoV-2 genome sequencing using the Ion AmpliSeq SARS-CoV-2 Panel on 22 FFPE lung tissues from 16 deceased coronavirus disease 2019 (COVID-19) patients. SARS-CoV-2 was detected in all FFPE blocks using a real-time RT-qPCR targeting the E gene with crossing point (Cp) values ranging from 16.02 to 34.16. Sequencing was considered as contributory (i.e. with a uniformity >55%) for 17 FFPE blocks. Adapting the number of target amplification PCR cycles according to the RT-qPCR Cp values allowed optimization of the sequencing quality for the contributory blocks (i.e. 20 PCR cycles for blocks with a Cp value <28 and 25 PCR cycles for blocks with a Cp value between 28 and 30). Most blocks with a Cp value >30 were non-contributory. Comparison of matched frozen and FFPE tissues revealed discordance for only three FFPE blocks, all with a Cp value >28. Variant identification and clade classification was possible for 13 patients. This study validates SARS-CoV-2 genome sequencing on FFPE blocks and opens the possibility to explore correlation between virus genotype and histopathologic lesions. |