Differential expression profiling of proteome for systemic lupus erythematosus with quantitative proteomic technique

AIM: To identify and quantify the total proteins in peripheral blood mononuclear cells (PBMC) of systemic lupus erythematosus (SLE) patients with quantitative proteomic technique, and to establish a differential expression profile of proteome for SLE. METHODS: Four-plex isobaric tags for relative and absolute quantification coupled with multiple chromatographic fractionation and tandem mass spectrometry were used to analyze the total proteins in PBMC from healthy controls and the patients of stable SLE, active SLE and rheumatoid arthritis. The proteins were identified by database searching with peptide mass fingerprinting. The differential expression of the proteins was compared. RESULTS: More than 400 proteins were identified. Compared with healthy controls, 44 proteins were discovered to be significantly expressed by more than 2 folds in stable SLE and active SLE, among which 9 proteins were up-regulated and 35 proteins were down-regulated. Compared with rheumatoid arthritis group, 52 proteins displayed 2 or more folds of changes in stable SLE and active SLE, including 19 up-regulated proteins and 33 down-regulated ones. The up-and down-regulated proteins between active SLE and stable SLE were 17 and 13, respectively. CONCLUSION: Quantitative proteomic technique is efficiently applicable for protein identification and relative quantitation in human peripheral blood mononuclear cells. Determination of the differentially expressed proteomic profile of SLE is helpful for better understanding the pathogenesis of SLE and developing new strategies for diagnosis and treatment of SLE.