Increased protein synthesis by cells exposed to a 1,800-MHz radio-frequency mobile phone electromagnetic field, detected by proteome profiling.

Purpose: To investigate whether or not low intensity radio frequency electromagnetic field exposure (RF-EME) associated with mobile phone use can affect human cells, we used a sensitive proteome analysis method to study changes in protein synthesis in cultured human cells.

Methods: Four different cell kinds were exposed to 2 W/kg specific absorption rate in medium containing 35S-methionine/cysteine, and autoradiography of 2D gel spots was used to measure the increased synthesis of individual proteins.

Results: While short-term RF-EME did not significantly alter the proteome, an 8-h exposure caused a significant increase in protein synthesis in Jurkat T-cells and human fibroblasts, and to a lesser extent in activated primary human mononuclear cells.

Cell characterization by proteome profiling applied to primary hepatocytes and hepatocyte cell lines Hep-G2 and Hep-3B.

Hepatocytes are known to express a large number of characteristic proteins. Transformed and cultured hepatocytes only partially maintain functional cell differentiation characteristics, which can be assessed by proteome profiling. Here, we applied 2D-PAGE analysis in addition to shotgun proteomics to assess the functional cell state of primary human hepatocytes (PHH), HepG2 and Hep3B cells.

Introducing the CPL/MUW proteome database: interpretation of human liver and liver cancer proteome profiles by referring to isolated primary cells.

Interpretation of proteome data with a focus on biomarker discovery largely relies on comparative proteome analyses. Here, we introduce a database-assisted interpretation strategy based on proteome profiles of primary cells. Both 2-D-PAGE and shotgun proteomics are applied.

Proteome maps of the main human peripheral blood constituents.

Clinical proteome analysis will almost inevitably be confronted with blood constituents. Purified plasma, serum, cell or tissue samples may easily be contaminated with some other constituents, affecting the final proteome analysis result. To recognize proteins which are potentially indicative for the presence of major blood constituents, we purified T cells, monocytes, neutrophils, erythrocytes, platelets and plasma and performed comparative proteome profiling employing 2D-PAGE in addition to shotgun proteomics.

Introducing a new parameter for quality control of proteome profiles: consideration of commonly expressed proteins.

Interpretation of proteome profiling experiments largely relies on comparative analyses. False-positive identifications may cause fatal misinterpretation of data. On the other hand, proteome analysis may also suffer from false negatives, when proteins that are actually present are not detected.

Consequences of acute and chronic oxidative stress upon the expression pattern of proteins in peripheral blood mononuclear cells.

Oxidative stress accompanies various diseases associated with chronic inflammation, including cancer. We exposed human peripheral blood mononuclear cells (PBMCs) to hydrogen peroxide in autologous plasma imitating in vivo conditions. Proteome alterations of metabolically labeled cells were recorded by means of 2D gel electrophoresis in addition to shotgun analysis.

Cytoplasmic proteome and secretome profiles of differently stimulated human dendritic cells.

Dendritic cells (DCs), the most potent and specialized antigen-presenting cells, play a key role in the regulation of the adaptive immunity. Immature DCs were generated by in vitro culturing of peripheral blood monocytes and functionally activated with the classical pathogen-associated molecular pattern lipopolysaccharide (LPS). Alternative activation resulting in Th-2 polarization was induced with lipid oxidation products derived from 1-palmitoyl-2-arachidoyl-sn-glycerol-3-phosphorylcholin (OxPAPC).

The cytoplasmic tail of CD45 is released from activated phagocytes and can act as an inhibitory messenger for T cells.

CD45 is the prototypic transmembrane protein tyrosine phosphatase (PTP), which is expressed on all nucleated hematopoietic cells and plays a central role in the integration of environmental signals into immune cell responses. Here we report an alternative function for the intracellular domain of CD45. We dis-covered that CD45 is sequentially cleaved by serine/metalloproteinases and gamma-secretases during activation of human monocytes and granulocytes by fungal stimuli or phorbol 12-myristate 13-acetate but not by other microbial stimuli.

Knowledge-based proteome profiling: considering identified proteins to evaluate separation efficiency by 2-D PAGE.

Proteome profiling techniques rely on the separation of proteins or peptides and their subsequent quantification. The reliability of this technique is still limited because a proteome profiling result does not necessarily represent the true protein composition of the analysed sample, thus seriously hampering proper data interpretation. Many experimentally observed proteome alterations are biologically not significant.