ddPCR used to measure cancer survival biomarker
5 Dec 2013
Researchers at Fred Hutchinson Cancer Research Center, Seattle have used Droplet Digital PCR to demonstrate the quantification of a tumour-attacking immune cell known to improve cancer survival.
The class of tumour-attacking immune cell, which is a subpopulation of T-cells called tumour-infiltrating T-lymphocytes (TILs), coupled with the latest research, enables further study of the role of TIL quantification in immunotherapy and as a cancer survival predictor.
Associate member of the public health sciences division at the research centre Dr Jason Bielas said: “There’s no way you could do this with any method other than digital PCR because of the numerous primer pairs and probes that we have (45 forward primers, 13 reverse primers, and 30 probes).
“Digital PCR partitions all the reactions so you can amplify these targets independently of PCR efficiency without any competing side reactions.”
The researchers developed the ddPCR-based “QuanTILfy” assay using Bio-Rad Laboratories’ QX100 ddPCR system.
They then used QuanTILfy to count TILs, determine their frequency and develop a grouping system to classify “clonality,” which might be a marker of druggable targets.
The researchers also demonstrated that QuanTILfy can be used to accurately and reproducibly characterise T-cell clonality in patients with T-cell acute lymphoblastic leukemia.
In each case, they saw a single QuanTILfy assay subgroup, indicative of clonal T-cell expansion. This finding was confirmed by deep sequencing.
