title: Controls to validate plasma samples for cell free DNA quantification.
abstract: Recent research has focused on the utility of cell free DNA (cfDNA) in serum and plasma for clinical application, especially in oncology. The literature holds promise of cfDNA as a valuable tumour marker to be used for treatment selection, monitoring and follow-up. The results, however, are diverging due to methodological differences with lack of standardisation and definition of sensitivity. The new biological information has not yet come into routine use. The present study presents external standardisation by spiking with non-human DNA fragments to control for loss of DNA during sample preparation and measurement. It also suggests a method to control for admixture of DNA from normal lymphocytes by utilizing the unique immunoglobulin gene rearrangement in the B-cells. The results show that this approach improves the quality of the analysis and lowers the risk of falsely increased values. In conclusion we suggest a new method to improve the accuracy of cfDNA measurements easily incorporated in the current technology.
authors.affiliation: Department of Biochemistry, Vejle Hospital, Kabbeltoft 25, DK-7100 Vejle, Denmark. Electronic address: nipa@regionsjaelland.dk.
authors.forename: Niels
authors.initials: N
authors.lastname: Pallisgaard
authors.affiliation: Department of Oncology, Vejle Hospital, Kabbeltoft 25, DK-7100 Vejle, Denmark; Department of Oncology, Aarhus University Hospital, Noerrebrogade 44, DK-8000 Aarhus, Denmark. Electronic address: k.g.spindler@rm.dk.
authors.forename: Karen-Lise Garm
authors.initials: KL
authors.lastname: Spindler
authors.affiliation: Department of Biochemistry, Vejle Hospital, Kabbeltoft 25, DK-7100 Vejle, Denmark. Electronic address: rikke.fredslund.andersen@rsyd.dk.
authors.forename: Rikke Fredslund
authors.initials: RF
authors.lastname: Andersen
authors.affiliation: Department of Biochemistry, Vejle Hospital, Kabbeltoft 25, DK-7100 Vejle, Denmark. Electronic address: ivan.brandslund@rsyd.dk.
authors.forename: Ivan
authors.initials: I
authors.lastname: Brandslund
authors.affiliation: Department of Oncology, Vejle Hospital, Kabbeltoft 25, DK-7100 Vejle, Denmark. Electronic address: anders.jakobsen@rsyd.dk.
authors.forename: Anders
authors.initials: A
authors.lastname: Jakobsen
mesh_terms: D000483:Alleles; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D004247:DNA / Q000097:blood / Q000235:genetics* / Q000276:immunology; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D006801:Humans; D016133:Polymerase Chain Reaction / Q000592:standards*; D012015:Reference Standards; D030262:Soybean Proteins
chemical_list: D004247:DNA; D004268:DNA-Binding Proteins; C411672:Cpp1 protein, soybean; D030262:Soybean Proteins
keywords: Lymphocyte DNA; Quality control; cfDNA; qPCR