Proteomic profiling using mass spectrometry--does normalising by total ion current potentially mask some biological differences?
Normalisation of data to minimise the impact of technical variation on comparative sample analysis is often carried out. Using SELDI data as a model, we have examined the effects of normalisation by TIC which is commonly used for MS data. Significant intergroup differences in normalisation factor were found for serum profiles which could not be explained by experimental factors, implying that normalisation by TIC may in some situations also normalise biological differences and should be systematically evaluated.
Cairns
David A
DA
Clinical and Biomedical Proteomics Group, Cancer Research UK Clinical Centre, Leeds Institute of Molecular Medicine, St. James's University Hospital, Leeds, UK.
Thompson
Douglas
D
Perkins
David N
DN
Stanley
Anthea J
AJ
Selby
Peter J
PJ
Banks
Rosamonde E
RE
D015415:Biomarkers / Q000032:analysis* / Q000737:chemistry; D002853:Chromatography, Liquid; D006801:Humans; D007477:Ions; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000601:surgery / Q000628:therapy; D016030:Kidney Transplantation; D040081:Protein Array Analysis; D040901:Proteomics / Q000379:methods; D006435:Renal Dialysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D015415:Biomarkers; D007477:Ions