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Objectives We characterized the transcriptional profiles of GM-CSF- (GM-MO) and M-CSF-induced macrophages (M-MO) and investigated in situ a subset of differentially expressed genes in human and mouse atherosclerotic lesions. Methods and results Using microarrays we identified a number of genes and biological processes differentially regulated in M-MO vs GM-MO. By varying in culture the M-CSF/GM-CSF ratio (0–10), a spectrum of macrophage phenotypes was explored by RT-QPCR. M-CSF (10ng/ml) stimulated expression of several genes, including selenoprotein-1 ( SEPP1 ), stabilin-1 ( STAB1 ) and CD163 molecule-like-1 ( CD163L1 ) which was inhibited by a low dose of GM-CSF (1ng/ml); M-CSF inhibited the expression of pro-platelet basic protein ( PPBP ) induced by GM-CSF. Combining Tissue Microarrays/quantitative immunohistochemistry of human aortic lesions with RT-QPCR expression data either from human carotids vs mammary non-atherosclerotic arteries or from the apoE null mice normal and atherosclerotic aortas showed that, STAB1 , SEPP1 and CD163L1 (M-CSF-sensitive genes) and PPBP (GM-CSF-sensitive gene) were expressed in both human arterial and apoE null mice atherosclerotic tissues. Conclusion A balance between M-CSF vs GM-CSF defines macrophage functional polarisation and may contribute to the progression of atherosclerosis.

Atherosclerosis as a chronic inflammatory disease resulting from the imbalance of the pro- and anti-inflammatory factors in the vessel wall. PAF and PAF-like oxidized phospholipids generated upon LDL oxidation in the intima of the arteries may interact with infiltrated monocytes/macrophages and lead to the alteration of gene expression patterns accompanied by an impaired production of chemokines, interleukins and proteolytic and lipolytic enzymes. The aim of this study was to evaluate the binding capacity of the major component of PAF-like oxidized phospholipids, namely the 1-palmitoyl-2-oxovaleroyl-sn-glycero-3-phosphorylcholine (POVPC) to PAF-receptor (PAF-R) on the surface of human monocytes/macrophages and to further characterize the gene expression induced by such binding. We show that, POVPC binds to cultured human macrophages via PAF-R and transduces the signals leading to the intracellular Ca(2+) fluxes and modifies the transcription levels of numerous pro-inflammatory and pro-atherogenic genes. Although a some similarity of the gene expression patterns was observed when macrophages were activated with POVPC versus PAF, we observed that only POVPC treatment induced a several-fold activation of IL-8 gene. In turn, only PAF activated PAF-R, matrix metalloproteinase-13 and 15-lipoxygenase mRNA accumulation. Thus, we suggest, that POVPC signals in mature macrophages only in part through the PAF-R, a part of its effects may involve other receptors.

Activation of NF-kappaB transcription factors requires phosphorylation and ubiquitin-proteasome-dependent degradation of IkappaB proteins. We provide evidence that a human F-box protein, h-betaTrCP, a component of Skp1-Cullin-F-box protein (SCF) complexes, a new class of E3 ubiquitin ligases, is essential for inducible degradation of IkappaBalpha. betaTrCP associates with Ser32-Ser36 phosphorylated, but not with unmodified IkappaBalpha or Ser32-Ser36 phosphorylation-deficient mutants. Expression of a F-box-deleted betaTrCP inhibits IkappaBalpha degradation, promotes accumulation of phosphorylated Ser32-Ser36 IkappaBalpha, and prevents NF-kappaB-dependent transcription. Our findings indicate that betaTrCP is the adaptor protein required for IkappaBalpha recognition by the SCFbetaTrCP E3 complex that ubiquitinates IkappaBalpha and makes it a substrate for the proteasome.

The Vpu and CD4 cytoplasmic domains were found, by using a two-hybrid assay in yeast, to interact in the absence of their membrane anchor domains. Studies on several deletion and point mutants revealed that the overall structure of the Vpu cytoplasmic domain is required for this interaction. The Vpu amino acid residues involved in the interaction with CD4 were identified. Deletion of the C-terminal residues of Vpu, required for CD4 degradation, as well as the double mutation on the casein kinase II phosphorylation sites S52N-S56N, also involved in CD4 degradation, resulted in the loss of interaction with CD4 and in the inability to induce CD4 degradation. These results suggest that the ability of Vpu to mediate the degradation of CD4 is linked to its capacity to physically interact with CD4. However, additional mutagenesis on the S52 site revealed that the interaction between the cytoplasmic domains of Vpu and CD4 is not sufficient for in vitro Vpu-mediated CD4 degradation.

Inorganic—organic copolymers (ORMOCERs = ORganically MOdified CERamics), which are synthesized by sol—gel processing, were developed as host materials for lithium salts. They consist of an inorganic oxidic backbone (Si, Zr, etc) chemically bonded to an organic network, eg by use of functionalized organosilanes, and are prepared by polycondensation (to form the inorganic oxidic network) in combination with organic crosslinking reactions. Dissolution of controlled amounts of LiClO4, in the ORMOCER-containing grafted polyethylene oxide leads to an electrolyte. The material is amorphous according to X-ray diffraction patterns. It has an ion conductivity of σ = 10−5 Ω−1 cm−1 at room temperature and σ = 10−3 Ω−1 cm−1 at 125°C. The material can be applied as coating or bulk by standard technologies and shows good adhesion to various substrate materials. Final curing can be initiated by uv-light and/or thermal treatment.