Validation of qPCR reference genes in lymphocytes from patients with amyotrophic lateral sclerosis

• Published in: PloS one Vol. 12; no. 3; p. e0174317
• Main Authors: Usarek, Ewa, Barańczyk-Kuźma, Anna, Kaźmierczak, Beata, Gajewska, Beata, Kuźma-Kozakiewicz, Magdalena
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 22.03.2017; Public Library of Science (PLoS)
• Subjects: Amyotrophic lateral sclerosis; Amyotrophic Lateral Sclerosis - genetics; Analysis; Biochemistry; Biology and Life Sciences; Cell lines; Cryopreservation; Cryopreservation - methods; Development and progression; Female; Gene expression; Gene Expression - genetics; Gene Expression Profiling - methods; Gene Expression Regulation, Neoplastic - genetics; Genes; Genetic aspects; Genomics; Glyceraldehyde-3-phosphate dehydrogenase; Humans; Immortalization; Leukocytes (mononuclear); Leukocytes, Mononuclear - metabolism; Liquid nitrogen; Lymphocytes; Lymphocytes - metabolism; Male; Medicine and Health Sciences; Middle Aged; Motor neurone disease; Mutation; Nitrogen; Patients; Peripheral blood mononuclear cells; Physical Sciences; Physiological aspects; Polymerase chain reaction; Real-Time Polymerase Chain Reaction - methods; Reference Standards; Research and Analysis Methods; RNA, Messenger - genetics; Studies; Transfection; Poland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0174317

Quantitative polymerase chain reaction (qPCR) is the most specific and reliable method for determination of mRNA gene expression. Crucial point for its accurate normalization is the choice of appropriate internal control genes (ICGs). In the present work we determined and compare the expression of eight commonly used ICGs in lymphocytes from 26 patients with amyotrophic lateral sclerosis (ALS) and 30 control subjects. Peripheral blood mononuclear cells (PBMCs) before and after immortalization by EBV transfection (lymphoblast cell lines-LCLs) were used for qPCR analysis. LCLs were studied before and after liquid nitrogen cryopreservation and culturing (groups LCL1 and LCL2, respectively). qPCR data of 8 ICGs expression was analyzed by BestKeeper, NormFinder and geNorm methods. All studied genes (18SRNA, ACTB, B2M, GUSB,GAPDH, HPRT1, MT-ATP6 and RPS17) were expressed in PBMCs, whereas only first four in LCLs. LCLs cryopreservation had no effect on ICGs expression. Comprehensive ranking indicated RPS17 with MT-ATP6 as the best ICGs for qPCR in PBMCs of control and ALS subjects, and RPS17 with 18RNA or MT-ATP6 in LCLs from ALS. In PBMCs 18RNA shouldn't be used as ICG.