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Gray, E. R.

Publications and source records attributed to Gray, E. R..

2 recordsLinked to original sources

ASPYRE-Lung: Validation of a simple, fast, robust and novel method for multi-variant genomic analysis of actionable NSCLC variants in tissue

Genomic variant testing of tumors is a critical gateway for patients to access the full potential of personalized oncology therapeutics. Current methods such as next-generation sequencing are costly and challenging to interpret, while PCR assays are limited in the number of variants they can cover. We developed ASPYRE(R) (Allele-Specific PYrophosphorolysis REaction) technology to address the urgent need for rapid, accessible and affordable diagnostics informing actionable genomic target variants of a given cancer. The targeted ASPYRE-Lung panel for non-small cell carcinoma covers 114 variants in 11 genes (ALK, BRAF, EGFR, ERBB2, KRAS, RET, ROS1, MET & NTRK1/2/3) to robustly inform clinical management. The assay detects single nucleotide variants, insertions, deletions, and gene fusions from tissue-derived DNA and RNA simultaneously. We tested the limit of detection, specificity, analytical accuracy and analytical precision of ASPYRE-Lung using FFPE lung tissue samples from patients with non-small cell lung carcinoma, variant-negative FFPE tissue from healthy donors, and FFPE-based contrived samples with controllable variant allele fractions. The sensitivity of ASPYRE-Lung was determined to be [≤] 3% variant allele fraction for single nucleotide variants and insertions or deletions, 100 copies for fusions, and 200 copies for MET exon 14 skipping. The specificity was 100% with no false positive results. The analytical accuracy test yielded no discordant calls between ASPYRE-Lung and expected results for clinical samples (via orthogonal testing) or contrived samples, and results were replicable across operators, reagent lots, runs, and real-time PCR instruments with a high degree of precision. The technology is simple and fast, requiring only four reagent transfer steps using standard laboratory equipment (PCR and qPCR instruments) with analysis via a cloud-based analysis algorithm. The ASPYRE-Lung assay has the potential to be transformative in facilitating access to rapid, actionable molecular profiling of tissue for patients with non-small cell carcinoma.

cancer biology↗

Characteristics of a Block to Entry via an HIV-2 Envelope, MCR

Successful viral infection depends not only on targeting the correct cell type, but also on the route taken into the cell. After entry, a retrovirus must reverse transcribe its genome and access the nucleus. Blocks to infection can arise at many different stages of the cycle; if they occur only in some cell types it can reveal hitherto unknown aspects of viral or cellular biology. A block to infection of a primary isolate of HIV-2 was previously identified in specific cell types. In this study, parameters of route of entry of the envelope protein from this primary isolate, MCR, were investigated. A critical component of the block acts at a pre-reverse transcription stage, as virions pseudotyped with MCR envelope did not undergo fusion and entry rates commensurate with productive infection. Furthermore, expression of p56lck, which regulates CD4 surface expression, partially rescued infection of MCR envelope-pseudotyped virus in restrictive cell types. Based on these findings, we propose that a part of this block results from poor cell-surface expression of CD4.

microbiology↗