title: Proteome analysis of B-cell maturation.
abstract: Proteins affected by anti-mIgM stimulation during B-cell maturation were identified using 2-DE-based proteomics. We investigated the proteome profiles of stimulated and nonstimulated Ramos B-cells at eight time points during 5 d and compared the obtained proteomic data to the corresponding data from DNA-microarray studies. Anti-mIgM stimulation of the cells resulted in significant differences (> or =twofold) in the protein abundance close to 100 proteins and differences in post-translational protein modifications. Forty-eight up- or down-regulated proteins were identified by mass spectrometric methods and database searches. The identities of a further nine proteins were revealed by comparing their positions to the known proteins in other lymphocyte 2-DE databases. Several of the proteins are directly related to the functional and morphological characteristics of B-cells, such as cytoskeleton rearrangement and intracellular signalling triggered by the crosslinking of B-cell receptors. In addition to proteins known to be involved in human B-cell maturation, we identified several proteins that were not previously linked to lymphocyte differentiation. The results provide deeper insights into the process of B-cell maturation and may lead to novel therapeutic strategies for immunodeficiencies. An interactive 2-DE reference map is available at http://bioinf.uta.fi/BcellProteome.
authors.affiliation: Institute of Medical Technology, University of Tampere, Tampere, Finland.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Salonen
authors.forename: Leena
authors.initials: L
authors.lastname: Valmu
authors.forename: Gunilla
authors.initials: G
authors.lastname: Rönnholm
authors.forename: Nisse
authors.initials: N
authors.lastname: Kalkkinen
authors.forename: Mauno
authors.initials: M
authors.lastname: Vihinen
mesh_terms: D001402:B-Lymphocytes / Q000737:chemistry* / Q000166:cytology* / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D015536:Down-Regulation / Q000502:physiology; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007075:Immunoglobulin M / Q000502:physiology; D020411:Oligonucleotide Array Sequence Analysis; D040081:Protein Array Analysis; D020543:Proteome / Q000235:genetics; D015854:Up-Regulation / Q000502:physiology
chemical_list: D007075:Immunoglobulin M; D020543:Proteome